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Sample records for klebsiella oxytoca bacteria

  1. Magnetic properties of biomineral particles produced by bacteria Klebsiella oxytoca

    NASA Astrophysics Data System (ADS)

    Raĭkher, Yu. L.; Stepanov, V. I.; Stolyar, S. V.; Ladygina, V. P.; Balaev, D. A.; Ishchenko, L. A.; Balasoiu, M.

    2010-02-01

    Ferrihydrite nanoparticles (2-5 nm in size) produced by bacteria Klebsiella oxytoca in the course of biomineralization of iron salt solutions from a natural medium exhibit unique magnetic properties: they are characterized by both the antiferromagnetic order inherent in a bulk ferrihydrite and the spontaneous magnetic moment due to the decompensation of spins in sublattices of a nanoparticle. The magnetic susceptibility enhanced by the superantiferromagnetism effect and the magnetic moment independent of the magnetic field provide the possibility of magnetically controlling these natural objects. This has opened up the possibilities for their use in nanomedicine and bioengineering. The results obtained from measurements of the magnetic properties of the ferrihydrite produced by Klebsiella oxytoca in its two main crystalline modifications are reported, and the data obtained are analyzed theoretically. This has made it possible to determine numerical values of the magnetic parameters of real biomineral nanoparticles.

  2. Klebsiella oxytoca Endocarditis With Complete Heart Block

    PubMed Central

    Ullah, Saad; Elbita, Omar; Abdelghany, Mahmoud; Tahir, Hassan; Tuli, Puneet; Alkilani, Waseem Zaid; Suri, Joshan

    2016-01-01

    Gram-negative bacterial endocarditis causes 5% of all bacterial endocarditis. Among gram-negative bacteria, Klebsiella species are rare causes of native valve endocarditis. Klebsiella oxytoca is an extremely rare subspecies that can infrequently cause endocarditis and is associated with poor outcome. We report a case of Klebsiella oxytoca endocarditis in an elderly man who initially presented with stroke but later developed sepsis and heart block secondary to endocarditis. PMID:27635410

  3. Klebsiella oxytoca: opportunistic infections in laboratory rodents.

    PubMed

    Bleich, Andre; Kirsch, Petra; Sahly, Hany; Fahey, Jim; Smoczek, Anna; Hedrich, Hans-Jürgen; Sundberg, John P

    2008-07-01

    Opportunistic pathogens have become increasingly relevant as the causative agents of clinical disease and pathological lesions in laboratory animals. This study was conducted to evaluate the role of Klebsiella oxytoca as an opportunistic pathogen in laboratory rodents. Therefore, K. oxytoca-induced lesions were studied from 2004 to early 2006 in naturally infected rodent colonies maintained at The Jackson Laboratory (TJL), Bar Harbor, USA, the Animal Research Centre (Tierforschungszentrum, TFZ) of the University of Ulm, Germany and the Central Animal Facility (ZTM) of the Hannover Medical School, Germany. K. oxytoca infections were observed in substrains of C3H/HeJ mice, which carry the Tlr4(Lps-d) allele; in LEW.1AR1-iddm rats, the latter being prone to diabetes mellitus; in immunodeficient NMRI-Foxn1(nu) mice; and in mole voles, Ellobius lutescens. The main lesions observed were severe suppurative otitis media, urogenital tract infections and pneumonia. Bacteriological examination revealed K. oxytoca as monocultures in all cases. Clonality analysis performed on strains isolated at the ZTM and TFZ (serotyping, pulse field gel electrophoresis [PFGE], enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction, sequencing of 16S rRNA and rpoB genes) revealed that the majority of bacteria belonged to two clones, one in each facility, expressing the capsule type K55 (ZTM) or K72 (TFZ). Two strains, one isolated at the ZTM and one at the TFZ, showed different PFGE and ERIC pattern than all other isolates and both expressed capsule type K35. In conclusion, K. oxytoca is an opportunistic pathogen capable of inducing pathological lesions in different rodent species.

  4. Nosocomial outbreak of Klebsiella pneumoniae carbapenemase-producing Klebsiella oxytoca in Austria.

    PubMed

    Hoenigl, Martin; Valentin, Thomas; Zarfel, Gernot; Wuerstl, Benjamin; Leitner, Eva; Salzer, Helmut J F; Posch, Josefa; Krause, Robert; Grisold, Andrea J

    2012-04-01

    To date, no outbreak of carbapenemase-producing bacteria has been reported for Austria. While outbreaks of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae have been increasingly reported, no outbreak caused by KPC-producing Klebsiella oxytoca has been described yet, to the best of our knowledge. We report an outbreak of KPC-producing K. oxytoca. In 5 months, 31 KPC-producing Klebsiella oxytoca strains were isolated from five patients. All patients were admitted to the same medical intensive care unit in Austria.

  5. Nosocomial Outbreak of Klebsiella pneumoniae Carbapenemase-Producing Klebsiella oxytoca in Austria

    PubMed Central

    Hoenigl, Martin; Valentin, Thomas; Zarfel, Gernot; Wuerstl, Benjamin; Leitner, Eva; Salzer, Helmut J. F.; Posch, Josefa; Krause, Robert

    2012-01-01

    To date, no outbreak of carbapenemase-producing bacteria has been reported for Austria. While outbreaks of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae have been increasingly reported, no outbreak caused by KPC-producing Klebsiella oxytoca has been described yet, to the best of our knowledge. We report an outbreak of KPC-producing K. oxytoca. In 5 months, 31 KPC-producing Klebsiella oxytoca strains were isolated from five patients. All patients were admitted to the same medical intensive care unit in Austria. PMID:22290949

  6. Decarboxylative Conversion of Hydroxycinnamic Acids by Klebsiella oxytoca and Erwinia uredovora, Epiphytic Bacteria of Polymnia sonchifolia Leaf, Possibly Associated with Formation of Microflora on the Damaged Leaves.

    PubMed

    Hashidoko, Y; Urashima, M; Yoshida, T; Mizutani, J

    1993-01-01

    Two bacteria, Klebsiella oxytoca and Erwinia uredovora, which constituted epiphytic microftora on yacon (Polymnia sonchifolia) leaves, converted hydroxycinnamic acids into hydroxystyrenes decarboxylatively. Hydroxycinnamate decarboxylase was extracted as crude protein from the bacterial cells, and was substrate-inducible. This decarboxylation was for the bacteria a detoxification of hydroxycinnamic acids of plants, but the metabolites were toxic to other test bacteria and fungi, including some phytopathogens. The possible ecological role of these epiphytic bacteria on the host-plant was discussed. from the viewpoint of their chemical interaction via the styrene derivatives.

  7. Characterization of bio-synthesized nanoparticles produced by Klebsiella oxytoca

    NASA Astrophysics Data System (ADS)

    Anghel, L.; Balasoiu, M.; Ishchenko, L. A.; Stolyar, S. V.; Kurkin, T. S.; Rogachev, A. V.; Kuklin, A. I.; Kovalev, Yu S.; Raikher, Yu L.; Iskhakov, R. S.; Duca, G.

    2012-03-01

    Structural and morphological properties of biogenic ferrihydrite nanoparticles produced by bacteria Klebsiella oxytoca are investigated. The stability of water dispersions of biomineral particles produced by Klebsiella oxytoca was monitored by UV-Vis spectroscopy. Their chemical composition was determined by FT-IR spectroscopy. The vibrational spectra of biogenic ferrihydrite nanoparticles revealed typical absorption peaks of exopolysaccharides. Morphological analysis based on Raman spectroscopy indicated the presence of exopolysaccharides on the surface as well as inside the pores of the ferrihydrite nanoparticles. Structural investigations of ultrasonic assisted samples of different concentration of water dispersed particles were performed using small angle X-ray scattering analysis. Model calculations and fitting procedures revealed scattering objects of an elongated shape with 6.73±0.16 nm radius of gyration.

  8. Complete Genome Sequence of Klebsiella oxytoca Strain JKo3

    PubMed Central

    Ogura, Yoshitoshi; Hayashi, Tetsuya; Mizunoe, Yoshimitsu

    2016-01-01

    Klebsiella oxytoca can be either pathogenic or beneficial, depending on conditions. These opposing characteristics have not been fully elucidated. Here, we report the complete sequence of the K. oxytoca JKo3 genome, consisting of a single circular chromosome of 5,943,791 bp and four plasmids. PMID:27811101

  9. First report of septic arthritis caused by Klebsiella oxytoca.

    PubMed

    Ménard, Armelle; Harambat, Jérome; Pereyre, Sabine; Pontailler, Jean-Roger; Mégraud, Francis; Richer, Olivier

    2010-08-01

    Klebsiella oxytoca is known to be a pathogen in immunodeficient adults and children. Here we report the first case of a K. oxytoca infection associated with spontaneous arthritis of the knee in a child with no history of immunosuppressive therapy or previous bacterial infections. Despite an initial antibiotic treatment failure, a second treatment led to a cure of the infection with no joint sequelae.

  10. Production of Biohydrogen from Wastewater by Klebsiella oxytoca ATCC 13182.

    PubMed

    Thakur, Veena; Tiwari, K L; Jadhav, S K

    2015-08-01

    Production of biohydrogen from distillery effluent was carried out by using Klebsiella oxytoca ATCC 13182. The work focuses on optimization of pH, temperature, and state of bacteria, which are the various affecting factors for fermentative biohydrogen production. Results indicates that at 35 °C for suspended cultures, the production was at its maximum (i.e., 91.33 ± 0.88 mL) when compared with other temperatures. At 35 °C and at pH 5 and 6, maximum productions of 117.67 ± 1.45 and 111.67 ± 2.72 mL were observed with no significant difference. When immobilized, Klebsiella oxytoca ATCC 13182 was used for biohydrogen production at optimized conditions, production was 186.33 ± 3.17 mL. Hence, immobilized cells were found to be more advantageous for biological hydrogen production over suspended form. Physicochemical analysis of the effluent was conducted before and after fermentation and the values suggested that the fermentative process is an efficient method for biological treatment of wastewater.

  11. Chronic pneumonia due to Klebsiella oxytoca mimicking pulmonary tuberculosis.

    PubMed

    Gera, Kamal; Roshan, Rahul; Varma-Basil, Mandira; Shah, Ashok

    2015-01-01

    Klebsiella species infrequently cause acute community acquired pneumonia (CAP). The chronic form of the disease caused by K. pneumoniae (Friedlander's bacillus) was occasionally seen in the pre-antibiotic era. K. oxytoca is a singularly uncommon cause of CAP. The chronic form of the disease caused by K. oxytoca has been documented only once before. A 50-year-old immunocompetent male smoker presented with haemoptysis for 12 months. Imaging demonstrated a cavitary lesion in the right upper lobe with emphysematous changes. Sputum stains and cultures for Mycobacterium tuberculosis were negative. However, three sputum samples for aerobic culture as well as bronchial aspirate cultured pure growth of K. oxytoca. A diagnosis of chronic pneumonia due to K. oxytoca was established and with appropriate therapy, the patient was largely asymptomatic. The remarkable clinical and radiological similarity to pulmonary tuberculosis can result in patients with chronic Klebsiella pneumonia erroneously receiving anti-tuberculous therapy.

  12. Isolation and characterisation of lytic bacteriophages of Klebsiella pneumoniae and Klebsiella oxytoca.

    PubMed

    Karumidze, Natia; Kusradze, Ia; Rigvava, Sophio; Goderdzishvili, Marine; Rajakumar, Kumar; Alavidze, Zemphira

    2013-03-01

    Klebsiella bacteria have emerged as an increasingly important cause of community-acquired nosocomial infections. Extensive use of broad-spectrum antibiotics in hospitalised patients has led to both increased carriage of Klebsiella and the development of multidrug-resistant strains that frequently produce extended-spectrum β-lactamases and/or other defences against antibiotics. Many of these strains are highly virulent and exhibit a strong propensity to spread. In this study, six lytic Klebsiella bacteriophages were isolated from sewage-contaminated river water in Georgia and characterised as phage therapy candidates. Two of the phages were investigated in greater detail. Biological properties, including phage morphology, nucleic acid composition, host range, growth phenotype, and thermal and pH stability were studied for all six phages. Limited sample sequencing was performed to define the phylogeny of the K. pneumoniae- and K. oxytoca-specific bacteriophages vB_Klp_5 and vB_Klox_2, respectively. Both of the latter phages had large burst sizes, efficient rates of adsorption and were stable under different adverse conditions. Phages reported in this study are double-stranded DNA bacterial viruses belonging to the families Podoviridae and Siphoviridae. One or more of the six phages was capable of efficiently lysing ~63 % of Klebsiella strains comprising a collection of 123 clinical isolates from Georgia and the United Kingdom. These phages exhibit a number of properties indicative of potential utility in phage therapy cocktails.

  13. Characterisation, biotyping, antibiogram and klebocin typing of Klebsiella with special reference to Klebsiella oxytoca.

    PubMed

    Aggarwal, Aruna; Khanna, Saroj; Arora, Usha

    2003-02-01

    400 strains of Klebsiellae identified by culture characteristics and biochemical reactions were subjected to biotyping, antibiogram and klebocin typing. Based on indole production, pectin and gelatin liquefaction 16.0% of all the isolates were Klebsiella oxytoca. Maximum sensitivity was shown to Amikacin (72%) and maximum resistance to Ampicillin (87.5%). Klebocin typability was 73.5%. So by combining biotyping, antibiogram and Klebocin typing, Klebsiella could be differentiated better than based on any single marker.

  14. Pleural empyema caused by Klebsiella oxytoca: a case series.

    PubMed

    Suthers, Elizabeth; Rosenstengel, Andrew; Hart, Julie; Lewis, Joshua R; Kay, Ian; Waterer, Grant; Lee, Y C Gary; Brims, Fraser

    2015-04-01

    We report on 19 patients from Western Australia of pleural empyema with Klebsiella oxytoca, an organism never before reported in association with this condition. Median age was 65 years, 14/17 (83%) had been in hospital within 30 days prior to diagnosis, 12/18 (67%) had active cancer, 9/17 (53%) had been in intensive care and 7/17 (41%) had prior surgery. Nine patients died at the time of censure, five within 90 days of infection.

  15. Detection of metallo-β-lactamase genes in clinically isolated Klebsiella pneumoniae and Klebsiella oxytoca.

    PubMed

    Tateno, Hidetsugu; Yasuhara, Tsutomu; Sugano, Emi; Tahara, Sachiko; Ugajin, Kazuhisa; Fukuchi, Kunihiko

    2014-12-01

    We detected and characterized metallo-β-lactamase genes (blaIMP-1 and blaIMP-11) in third generation cephalosporin-resistant Klebsiella pneumoniae and Klebsiella oxytoca isolated at Showa University Hospital between January 1, 2011 and December 31, 2012. The cephalosporin-resistant K pneumoniae strains were frequently isolated from the urine, while one strain of K. pneumoniae, which was resistant to carbapenem, was isolated from the stool. We analyzed the phenotypes and genotypes of the metallo-β-lactamase genes from the 16 strains of cephalosporin-resistant-K pneumoniae and 6 strains of -K. oxytoca isolated from the same ward. The minimum inhibitory concentrations of imipenem were below 4 µg/ml in 21 out of the 22 isolated strains. The double disc synergy test using ceftazidime and sodium mercaptoacetic acid revealed enlargements in the inhibitory zones of 14 of the 16 strains of K. pneumoniae and all 6 strains of K. oxytoca. Metallo-β-lactamase genes were detected in all of the tested strains, with blaIMP-1 in 3 K. pneumoniae and 1 K. oxytoca, blaIMP-11 in 13 K pneumoniae and 4 K. oxytoca, and both blaIMP-1 and blaIMP-11 in one K. oxytoca. Our results indicate that third generation cephalosporin-resistant and imipenem-susceptible K. pneumoniae and K. oxytoca possess the metallo-β-lactamase gene. The active surveillance of metallo-β-lactamase genes should be performed in clinical laboratories. (Original).

  16. Isolation and characterization of an SDS-degrading Klebsiella oxytoca.

    PubMed

    Shukor, M Y; Husin, W S W; Rahman, M F A; Shamaan, N A; Syed, M A

    2009-01-01

    Sodium dodecyl sulfate (SDS) is one of the main components in the detergent and cosmetic industries. Its bioremediation by suitable microorganism has begun to receive greater attention as the amount of SDS usage increases to a point where treatment plants would not be able to cope with the increasing amount of SDS in wastewater. The purpose of this work was to isolate local SDS-degrading bacteria. Screening was carried out by the conventional enrichment-culture technique. Six SDS-degrading bacteria were isolated. Of these isolates, isolate S14 showed the highest degradation of SDS with 90% degradation after three days of incubation. Isolate S14 was tentatively identified as Klebsiella oxytoca strain DRY14 based on carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. SDS degradation by the bacterium was optimum at 37 degrees 0. Ammonium sulphate; at 2.0 g l(-1), was found to be the best nitrogen source for the growth of strain DRY14. Maximum growth on SDS was observed at pH 7.25. The strain exhibited optimum growth at SDS concentration of 2.0 g l(-1) and was completely inhibited at 10 g l(-1) SDS. At the tolerable initial concentration of 2.0 g l(-1), almost 80% of 2.0 g l(-1) SDS was degraded after 4 days of incubation concomitant with increase in cellular growth. The K(m(app) and V(max(app)) values calculated for the alkylsulfatase from this bacterium were 0.1 mM SDS and 1.07 micromol min(-1) mg(-1) protein, respectively.

  17. First Description of KPC-2-Producing Klebsiella oxytoca in Brazil

    PubMed Central

    Cavalcanti, Felipe L. S.; Martins, Willames M. B.; Vilela, Marinalda A.; Gales, Ana C.; Morais Junior, Marcos A.; Morais, Márcia M. C.

    2013-01-01

    The present work reports the detection of the first case of nosocomial Klebsiella oxytoca producing class A carbapenemase KPC-2 in Brazil. The isolate KPN106 carried a 65-kb IncW-type plasmid that harbors the blaKPC gene and Tn4401b. Moreover, we detected the presence of a class 1 integron containing a new allele, arr-8, followed by a 5′-truncated dhfrIIIc gene. In view of the recent results, we emphasize the high variability of the bacterial and genetic hosts of this resistance determinant. PMID:23752512

  18. First description of KPC-2-producing Klebsiella oxytoca in Brazil.

    PubMed

    Almeida, Anna C S; Cavalcanti, Felipe L S; Martins, Willames M B; Vilela, Marinalda A; Gales, Ana C; Morais Junior, Marcos A; Morais, Márcia M C

    2013-08-01

    The present work reports the detection of the first case of nosocomial Klebsiella oxytoca producing class A carbapenemase KPC-2 in Brazil. The isolate KPN106 carried a 65-kb IncW-type plasmid that harbors the blaKPC gene and Tn4401b. Moreover, we detected the presence of a class 1 integron containing a new allele, arr-8, followed by a 5'-truncated dhfrIIIc gene. In view of the recent results, we emphasize the high variability of the bacterial and genetic hosts of this resistance determinant.

  19. Proteomic analysis of the effect of cyanide on Klebsiella oxytoca.

    PubMed

    Tang, Petrus; Hseu, You-Cheng; Chou, Hui-Hsuan; Huang, Kuo-Yang; Chen, Ssu Ching

    2010-03-01

    Cyanide has been proved to be degraded by Klebsiella oxytoca. In order to examine the physiological responses of cyanide degradation by this bacterium, two-dimensional (2-DE) electrophoresis approach and MALDI-TOF-MS allow us to identify 106 proteins spots that were significantly altered in the presence of 1 mM cyanide in relative to that in 1 mM ammonia when K. oxytoca grown at the late-log phase. Among them, 27 proteins were successfully identified. These proteins were involved in carbohydrate metabolism, nucleotide metabolism, amino acid metabolism, nitrogen metabolism, stress responses, oxidation-reduction reactions, transporters, and miscellaneous function. Some proteins related with regulation of nitrogen assimilation pathways (glutamine synthetase), oxidative stress repairing (catalase), and protection (neutral trehalase and glycosyltransferase) could improve the effectiveness of cyanide biodegradation. Although the nitrogenase was suggested to participate in cyanide degradation in our previous study, this enzyme induction was not observed as expected. These findings could provide new insights into the inducible mechanisms underlying the capacity of K. oxytoca to tolerate cyanide stress.

  20. Klebsiella oxytoca with reduced sensitivity to chlorhexidine isolated from a diabetic foot ulcer.

    PubMed

    Vali, Leila; Dashti, Ali A; El-Shazly, Sherief; Jadaon, Mehrez M

    2015-05-01

    In most hospitals, chlorhexidine is used as skin antiseptic prior to clinical procedures, in dressings and when bathing patients. We hereby report, for the first time, the isolation of a clinical Klebsiella oxytoca isolate with reduced sensitivity to chlorhexidine from a foot ulcer of a diabetic patient, which is a common and serious complication associated with diabetes. The Minimum Inhibitory Concentration of the K. oxytoca isolate to chlorhexidine was found to be 30 mg/L and the Minimum Bactericidal Concentration was 60 mg/L. An increased resistance to ethidium bromide (MIC 200 mg/ L) was also observed. Molecular tests revealed that the isolate contained blaCTXM15, blaT(EM-1) and bla(SHV). The other resistant genes detected were qnrB1 and aac(6')-Ib-cr. The resistant determinants were located on a class I integron integrase (intI1) containing qacE gene. DNA sequencing showed homology to K. oxytoca plasmid pACM1. Identification of K. oxytoca with reduced sensitivity to chlorhexidine raises concern regarding dilution standards in hospitals. Adherence to the hospitals' infection control policies should be strictly monitored to avoid continuous low level exposure of bacteria to biocides, specifically in developing countries.

  1. Infective endocarditis caused by Klebsiella oxytoca in an intravenous drug user with cancer

    PubMed Central

    Hall, Connor; Hatch, Michael; Ayan, Mohamed; Winn, Richard

    2016-01-01

    Infective endocarditis caused by Klebsiella species is rare, with most isolates being K. pneumoniae. We report the case of a 24-year-old intravenous drug user with newly diagnosed seminoma who developed K. oxytoca endocarditis. In addition to having K. oxytoca isolated from blood culture, cultures of that species were obtained from a retroperitoneal metastasis found on original presentation. PMID:27034562

  2. Improvements In Ethanologenic Escherichia Coli and Klebsiella Oxytoca

    SciTech Connect

    Dr. David Nunn

    2010-09-30

    The current Verenium cellulosic ethanol process is based on the dilute-acid pretreatment of a biomass feedstock, followed by a two-stage fermentation of the pentose sugar-containing hydrolysate by a genetically modified ethanologenic Escherichia coli strain and a separate simultaneous saccharification-fermentation (SSF) of the cellulosic fraction by a genetically modified ethanologenic Klebsiella oxytoca strain and a fungal enzyme cocktail. In order to reduce unit operations and produce a fermentation beer with higher ethanol concentrations to reduce distillation costs, we have proposed to develop a simultaneous saccharification co-fermentation (SScF) process, where the fermentation of the pentose-containing hydrolysate and cellulosic fraction occurs within the same fermentation vessel. In order to accomplish this goal, improvements in the ethanologens must be made to address a number of issues that arise, including improved hydrolysate tolerance, co-fermentation of the pentose and hexose sugars and increased ethanol tolerance. Using a variety of approaches, including transcriptomics, strain adaptation, metagenomics and directed evolution, this work describes the efforts of a team of scientists from Verenium, University of Florida, Massachusetts Institute of Technology and Genomatica to improve the E. coli and K. oxytoca ethanologens to meet these requirements.

  3. Forehead abscess caused by Klebsiella oxytoca with undiagnosed type 2 diabetes.

    PubMed

    Sohn, Won-Il; Seo, Bommie F; Jung, Sung-No

    2012-05-01

    Klebsiella is an opportunistic pathogen that is known to cause septicemia, pneumonia, urinary tract infections, hepatobiliary tract infections, and soft tissue infections in patients who have severe underlying diseases or are under immunosuppression. Most Klebsiella species found are Klebsiella pneumoniae, and Klebsiella oxytoca is rarely cultured in humans. We report a case of a 48-year-old man presenting with a soft fluctuating mass on his forehead. The lesion was an abscess, and percutaneous drainage yielded pus from which K. oxytoca was isolated. Parenteral levofloxacin was administrated leading to resolution of infection signs. Because of the rarity of the pathogen, evaluation for underlying illnesses was done, and the patient was diagnosed with type 2 diabetes mellitus. This is the first report of a patient with previously undiagnosed diabetes who was found with an extraorbital abscess caused by K. oxytoca, which we present with a review of diagnosis, pathogenesis, and treatment.

  4. Gut eradication of VIM-1 producing ST9 Klebsiella oxytoca after fecal microbiota transplantation for diarrhea caused by a Clostridium difficile hypervirulent R027 strain.

    PubMed

    García-Fernández, Sergio; Morosini, María-Isabel; Cobo, Marta; Foruny, José Ramón; López-Sanromán, Antonio; Cobo, Javier; Romero, José; Cantón, Rafael; Del Campo, Rosa

    2016-12-01

    We report the fecal carriage eradication of a VIM-1-producing ST9 Klebsiella oxytoca strain in a pluripathological 84-year-old woman after fecal microbiota transplantation to control relapsing R027 hypervirulent Clostridium difficile infections. The donor was her son, in which the absence of fecal carbapenemase-producing bacteria was corroborated.

  5. A case of testicular infarction from the complications of Klebsiella oxytoca induced acute epididymitis.

    PubMed

    Lee, Wonae; Park, Heeyoon; Lee, Gilho

    2016-04-01

    Herein, we reported a case of testicular infarction in a patient with Klebsiella oxytoca induced acute epididymitis. Acute left epididymitis progressed into testicular infarction requiring orchiectomy in spite of antibiotics treatment. Ordinary urine cultures did not reveal any specific organism, suggesting viable but noncultureable state. We amplified a bacterial 16S ribosomal subunit gene from the urine and orchiectomized samples, and we found K. oxytoca infections from both of them.

  6. Refactoring the nitrogen fixation gene cluster from Klebsiella oxytoca.

    PubMed

    Temme, Karsten; Zhao, Dehua; Voigt, Christopher A

    2012-05-01

    Bacterial genes associated with a single trait are often grouped in a contiguous unit of the genome known as a gene cluster. It is difficult to genetically manipulate many gene clusters because of complex, redundant, and integrated host regulation. We have developed a systematic approach to completely specify the genetics of a gene cluster by rebuilding it from the bottom up using only synthetic, well-characterized parts. This process removes all native regulation, including that which is undiscovered. First, all noncoding DNA, regulatory proteins, and nonessential genes are removed. The codons of essential genes are changed to create a DNA sequence as divergent as possible from the wild-type (WT) gene. Recoded genes are computationally scanned to eliminate internal regulation. They are organized into operons and placed under the control of synthetic parts (promoters, ribosome binding sites, and terminators) that are functionally separated by spacer parts. Finally, a controller consisting of genetic sensors and circuits regulates the conditions and dynamics of gene expression. We applied this approach to an agriculturally relevant gene cluster from Klebsiella oxytoca encoding the nitrogen fixation pathway for converting atmospheric N(2) to ammonia. The native gene cluster consists of 20 genes in seven operons and is encoded in 23.5 kb of DNA. We constructed a "refactored" gene cluster that shares little DNA sequence identity with WT and for which the function of every genetic part is defined. This work demonstrates the potential for synthetic biology tools to rewrite the genetics encoding complex biological functions to facilitate access, engineering, and transferability.

  7. Modulation of mgrB gene expression as a source of colistin resistance in Klebsiella oxytoca.

    PubMed

    Jayol, Aurélie; Poirel, Laurent; Villegas, Maria-Virginia; Nordmann, Patrice

    2015-07-01

    Gene modifications in the PmrAB and PhoPQ two-component regulatory systems, as well as inactivation of the mgrB gene, are known to be causes of colistin resistance in Klebsiella pneumoniae. The objective of this study was to characterise the mechanism involved in colistin resistance in a Klebsiella oxytoca isolate. A K. oxytoca clinical isolate showing resistance to colistin was recovered in Cali, Colombia. The pmrA, pmrB, phoP, phoQ and mgrB genes were amplified and sequenced. Wild-type mgrB genes from K. pneumoniae and K. oxytoca were cloned, and corresponding recombinant plasmids were used for complementation assays. By analysing the mgrB gene of the K. oxytoca isolate and its flanking sequences, an insertion sequence (IS) of 1196bp was identified in its promoter region. The insertion was located between nucleotides -39 and -38 when referring to the start codon of the mgrB gene, thus negatively interfering with expression of the mgrB gene by modifying its promoter structure. This IS was very similar to ISKpn26 (99% nucleotide identity) belonging to the IS5 family. Complementation assays with mgrB genes from wild-type K. pneumoniae or K. oxytoca restored full susceptibility to colistin. In conclusion, here we identified the mechanism involved in colistin resistance in a K. oxytoca isolate. Modulation of mgrB gene expression was the key factor for this acquired resistance to colistin.

  8. Complete genome sequence of Klebsiella oxytoca KCTC 1686, used in production of 2,3-butanediol.

    PubMed

    Shin, Sang Heum; Kim, Sewhan; Kim, Jae Young; Lee, Soojin; Um, Youngsoon; Oh, Min-Kyu; Kim, Young-Rok; Lee, Jinwon; Yang, Kap-Seok

    2012-05-01

    Here we report the full genome sequence of Klebsiella oxytoca KCTC 1686, which is used in production of 2,3-butanediol. The KCTC 1686 strain contains 5,974,109 bp with G+C content of 56.05 mol% and contains 5,488 protein-coding genes and 110 structural RNAs.

  9. A new assay for the simultaneous identification and differentiation of Klebsiella oxytoca strains.

    PubMed

    Stojowska-Swędrzyńska, Karolina; Krawczyk, Beata

    2016-12-01

    Klebsiella oxytoca is the second most frequently identified species of Klebsiella isolated from hospitalized patients. Klebsiella spp. is difficult to identify using conventional methods and is often misclassified in clinical microbiology laboratories. K. oxytoca is responsible for an increasing number of multi-resistant infections in hospitals because of insufficient detection and identification. In this study, we propose a new simple method called pehX-LM PCR/XbaI, which simultaneously indicates K. oxytoca species and genotype by the fingerprint pattern. The pehX-LM PCR/XbaI is a combination of the following two methods: species-specific amplification of pehX gene and non-specific amplification of short restriction fragments by the LM PCR method. The specificity and the discrimination power of the pehX-LM PCR/XbaI method were determined by typing 209 K. oxytoca strains (included 9 reference strains), 28 K. pneumoniae, and other 25 strains belonging to the Enterobacteriaceae. The typing results were confirmed by the PCR melting profile method. Unlike the known fingerprinting methods, the pehX-LM PCR/XbaI leads to a clear pattern (approx. 3-5 bands) with a sufficient, relatively high discriminatory power. As a result, the time and cost of a single analysis are lower. The method can be used both in clinical and environmental research.

  10. Identification of acetoin reductases involved in 2,3-butanediol pathway in Klebsiella oxytoca.

    PubMed

    Yang, Taek Ho; Rathnasingh, Chelladurai; Lee, Hee Jong; Seung, Doyoung

    2014-02-20

    The acetoin reductase (AR) of Klebsiella oxytoca is responsible for converting acetoin into 2,3-butanediol (2,3-BDO) during sugar fermentation. Deleting the AR encoding gene (budC) in the 2,3-BDO operon does not block production of 2,3-BDO, as another similar gene exists in addition to budC called diacetyl/acetoin reductase (dar) which shares 53% identity with budC. In the present study, both budC and dar of K. oxytoca were independently cloned and expressed in Escherichia coli along with budA (acetolactate decarboxylase) and budB (acetolactate synthase), which are responsible for converting pyruvate into acetoin. The recombinant E. coli expressing budABC and budAB-dar produced 2,3-BDO from glucose but E. coli expressing only budAB did not and produced acetoin alone. This demonstrates that Dar functions similar to BudC. Mutants of budC, dar, and both genes together were developed in K. oxytoca ΔldhA (lactate dehydrogenase). K. oxytoca ΔldhA ΔbudC Δdar, deficient in both AR genes, showed reduced 2,3-BDO concentration when compared to K. oxytoca ΔldhA and K. oxytoca ΔldhA ΔbudC by 84% and 69%, respectively. Interestingly, K. oxytoca ΔldhA Δdar resulted in a significant reduction in the reversible conversion of 2,3-BDO into acetoin than that of K. oxytoca ΔldhA, which was observed in a glucose depleted fermentation culture. In addition, we observed that Dar played a key role in dissimilation of 2,3-BDO in media containing 2,3-BDO alone.

  11. Cytotoxic and pathogenic properties of Klebsiella oxytoca isolated from laboratory animals.

    PubMed

    Darby, Alison; Lertpiriyapong, Kvin; Sarkar, Ujjal; Seneviratne, Uthpala; Park, Danny S; Gamazon, Eric R; Batchelder, Chara; Cheung, Cheryl; Buckley, Ellen M; Taylor, Nancy S; Shen, Zeli; Tannenbaum, Steven R; Wishnok, John S; Fox, James G

    2014-01-01

    Klebsiella oxytoca is an opportunistic pathogen implicated in various clinical diseases in animals and humans. Studies suggest that in humans K. oxytoca exerts its pathogenicity in part through a cytotoxin. However, cytotoxin production in animal isolates of K. oxytoca and its pathogenic properties have not been characterized. Furthermore, neither the identity of the toxin nor a complete repertoire of genes involved in K. oxytoca pathogenesis have been fully elucidated. Here, we showed that several animal isolates of K. oxytoca, including the clinical isolates, produced secreted products in bacterial culture supernatant that display cytotoxicity on HEp-2 and HeLa cells, indicating the ability to produce cytotoxin. Cytotoxin production appears to be regulated by the environment, and soy based product was found to have a strong toxin induction property. The toxin was identified, by liquid chromatography-mass spectrometry and NMR spectroscopy, as low molecular weight heat labile benzodiazepine, tilivalline, previously shown to cause cytotoxicity in several cell lines, including mouse L1210 leukemic cells. Genome sequencing and analyses of a cytotoxin positive K. oxytoca strain isolated from an abscess of a mouse, identified genes previously shown to promote pathogenesis in other enteric bacterial pathogens including ecotin, several genes encoding for type IV and type VI secretion systems, and proteins that show sequence similarity to known bacterial toxins including cholera toxin. To our knowledge, these results demonstrate for the first time, that animal isolates of K. oxytoca, produces a cytotoxin, and that cytotoxin production is under strict environmental regulation. We also confirmed tilivalline as the cytotoxin present in animal K. oxytoca strains. These findings, along with the discovery of a repertoire of genes with virulence potential, provide important insights into the pathogenesis of K. oxytoca. As a novel diagnostic tool, tilivalline may serve as a

  12. Detection and spread of oxa-48-producing Klebsiella oxytoca isolates in Istanbul, Turkey.

    PubMed

    Nazik, Hasan; Aydin, Selda; Albayrak, Rüveyda; Bilgi, Esma A; Yildiz, Ismail; Kuvat, Nuray; Kelesoglu, Fatih M; Kelesoglu, Fatih M; Pakaştiçali, Nagehan; Yilmaz, Fadime; Ongen, Betigül

    2014-01-01

    Five OXA-48 producing Klebsiella oxytoca strains isolated in April-July 2010 were analyzed. Antibiotic susceptibility tests were performed using disc diffusion method and VITEK 2 system. Carbapenemase activity was investigated using the Modified Hodge test. Beta-lactamase genes were detected by PCR and blaOXA-48 was sequenced. Genetic relatedness between K. oxytoca isolates was investigated by pulse-field gel electrophoresis (PFGE). Carbapenemase activity was detected in 5 isolates by Modified Hodge test. Although all strains were resistant to ertapenem and imipenem, only one strain was also resistant to meropenem. BlaOXA-48 in 4 isolates harbored 2 or 3 other ESBL types, namely, blaTEM, blaSHV, blaCTX-M, or blaVEB. PFGE revealed 3 different pulso-types among the K. oxytoca isolates. The presence of OXA-48 carbapenemase in other species of clinical isolates should also be considered.

  13. Contaminated Handwashing Sinks as the Source of a Clonal Outbreak of KPC-2-Producing Klebsiella oxytoca on a Hematology Ward

    PubMed Central

    Leitner, Eva; Zarfel, Gernot; Luxner, Josefa; Herzog, Kathrin; Pekard-Amenitsch, Shiva; Hoenigl, Martin; Valentin, Thomas; Feierl, Gebhard; Grisold, Andrea J.; Högenauer, Christoph; Sill, Heinz; Krause, Robert

    2014-01-01

    We investigated sinks as possible sources of a prolonged Klebsiella pneumonia carbapenemase (KPC)-producing Klebsiella oxytoca outbreak. Seven carbapenem-resistant K. oxytoca isolates were identified in sink drains in 4 patient rooms and in the medication room. Investigations for resistance genes and genetic relatedness of patient and environmental isolates revealed that all the isolates harbored the blaKPC-2 and blaTEM-1 genes and were genetically indistinguishable. We describe here a clonal outbreak caused by KPC-2-producing K. oxytoca, and handwashing sinks were a possible reservoir. PMID:25348541

  14. Contaminated handwashing sinks as the source of a clonal outbreak of KPC-2-producing Klebsiella oxytoca on a hematology ward.

    PubMed

    Leitner, Eva; Zarfel, Gernot; Luxner, Josefa; Herzog, Kathrin; Pekard-Amenitsch, Shiva; Hoenigl, Martin; Valentin, Thomas; Feierl, Gebhard; Grisold, Andrea J; Högenauer, Christoph; Sill, Heinz; Krause, Robert; Zollner-Schwetz, Ines

    2015-01-01

    We investigated sinks as possible sources of a prolonged Klebsiella pneumonia carbapenemase (KPC)-producing Klebsiella oxytoca outbreak. Seven carbapenem-resistant K. oxytoca isolates were identified in sink drains in 4 patient rooms and in the medication room. Investigations for resistance genes and genetic relatedness of patient and environmental isolates revealed that all the isolates harbored the blaKPC-2 and blaTEM-1 genes and were genetically indistinguishable. We describe here a clonal outbreak caused by KPC-2-producing K. oxytoca, and handwashing sinks were a possible reservoir.

  15. Recombinant Klebsiella oxytoca strains with improved efficiency in removal of high nitrate loads

    SciTech Connect

    Pinar, G.; Ramos, J.L.

    1998-12-01

    Klebsiella oxytoca CECT 4460 removes high nitrate loads from industrial wastewaters without accumulation of nitrite under optimal culture conditions; however, under nonoptimal conditions nitrite accumulates. This situation reflects an in vivo-limited functioning of nitrite reductase in this strain. As a way to overcome this limitation, an increase in the nitrite reductase gene dose in K. oxytoca CECT 4460 was considered. To achieve this, the authors cloned and transferred into this strain the Klebsiella pneumoniae nasB gene, which encodes assimilatory nitrite reductase. The delivery vector was either the wide-host-range plasmid pUPE2, in which the nasB gene is expressed from the Escherichia coli P{sub lac} promoter, or a mini-Tn5-Km vector, which upon random insertion in the host chromosome allowed expression of the nasB gene from an unidentified chromosomal host promoter. The effect of the increase in the dose of the nasB gene in K. oxytoca CECT 4460 on the accumulation of nitrite in the culture medium was tested in two recombinant strains. The results obtained showed that K. oxytoca CECT 4460 bearing pUPE2 accumulated 88% less nitrite than the wild-type strain, while the recombinant strain bearing the K. pneumoniae nasB gene in the host chromosome showed a 25% lower level of nitrite accumulation in the culture medium than that of the wild type.

  16. Outbreak of OXY-2-Producing Klebsiella oxytoca in a Renal Transplant Unit▿

    PubMed Central

    Zárate, Mariela Soledad; Gales, Ana C.; Picão, Renata C.; Pujol, Gervasio Soler; Lanza, Alejandra; Smayevsky, Jorgelina

    2008-01-01

    We describe a Klebsiella oxytoca infection outbreak in a renal transplant unit that involved seven patients. All strains belonged to a single pulsed-field gel electrophoresis pattern and were resistant to amoxicillin-clavulanate, cefuroxime, piperacillin-tazobactam, and aztreonam but susceptible to ceftriaxone, ceftazidime, cefepime, and imipenem. Chromosomal β-lactamase hyperproduction was caused by a point mutation in the blaOXY-2 gene promoter region. PMID:18417660

  17. Outbreak of OXY-2-Producing Klebsiella oxytoca in a renal transplant unit.

    PubMed

    Zárate, Mariela Soledad; Gales, Ana C; Picão, Renata C; Pujol, Gervasio Soler; Lanza, Alejandra; Smayevsky, Jorgelina

    2008-06-01

    We describe a Klebsiella oxytoca infection outbreak in a renal transplant unit that involved seven patients. All strains belonged to a single pulsed-field gel electrophoresis pattern and were resistant to amoxicillin-clavulanate, cefuroxime, piperacillin-tazobactam, and aztreonam but susceptible to ceftriaxone, ceftazidime, cefepime, and imipenem. Chromosomal beta-lactamase hyperproduction was caused by a point mutation in the bla(OXY-2) gene promoter region.

  18. [Capsular types, virulence factors and DNA types of Klebsiella oxytoca strains isolated from blood and bile].

    PubMed

    Ishihara, Yuka; Yagi, Tetsuya; Mochizuki, Mariko; Ohta, Michio

    2012-03-01

    Klebsiella oxytoca is an opportunistic pathogen and is isolated at the second highest frequency among genus Klebsiella from hospitalized patients. According to previous reports, the major virulence factors of K. pneumoniae include capsules and several kinds of pill, whereas the virulence factors of K. oxytoca have not been well investigated. We noticed an increased frequency of K. oxytoca isolates from patients who had undergone a biliary tract operation in a general hospital from May through November, 2009. We then performed a PCR analysis of the virulence factors and an epidemiological analysis with capsular typing (serotyping) and pulsed field gel electrophoresis (PFGE) for K. oxytoca of 11 blood isolates and 10 bile isolates. As a result, serotypes of K9, K15, K26, K31, K43, K47, K55, K70, and K79 were identified in these strains, and K1 and K2 which are frequent serotypes in K. pneumoniae strains were not observed. Two blood isolates of the K55 serotype showed almost the same PFGE pattern, suggesting that these isolates were very closely related and caused cross-infection in a hospital ward. Strains of the K43 serotype were three blood isolates and 1 bile isolate, all of which showed different PFGE patterns. There were no common isolates among the blood and bile isolates. A PCR search revealed that fimH and mrkD genes which are relevant to type 1 and type 2 pili, respectively, were present in all strains, whereas kfuBC, an iron uptake gene, and cf29a were detected in only a few strains. Neither of the mucoid phenotype-related genes magA and rmpA was present in any strains. These results strongly suggest that type 1 and/or type 3 pili would have important roles in the pathogenesis of blood infection and bile infection caused by K. oxytoca.

  19. Characterization of Piperacillin/Tazobactam-Resistant Klebsiella oxytoca Recovered from a Nosocomial Outbreak.

    PubMed

    Fujita, Ai; Kimura, Kouji; Yokoyama, Satoru; Jin, Wanchun; Wachino, Jun-Ichi; Yamada, Keiko; Suematsu, Hiroyuki; Yamagishi, Yuka; Mikamo, Hiroshige; Arakawa, Yoshichika

    2015-01-01

    We characterized 12 clinical isolates of Klebsiella oxytoca with the extended-spectrum β-lactamase (ESBL) phenotype (high minimum inhibitory concentration [MIC] values of ceftriaxone) recovered over 9 months at a university hospital in Japan. To determine the clonality of the isolates, we used pulsed-field gel electrophoresis (PFGE), multi-locus sequence typing (MLST), and PCR analyses to detect blaRBI, which encodes the β-lactamase RbiA, OXY-2-4 with overproduce-type promoter. Moreover, we performed the isoelectric focusing (IEF) of β-lactamases, and the determination of the MICs of β-lactams including piperacillin/tazobactam for 12 clinical isolates and E. coli HB101 with pKOB23, which contains blaRBI, by the agar dilution method. Finally, we performed the initial screening and phenotypic confirmatory tests for ESBLs. Each of the 12 clinical isolates had an identical PFGE pulsotype and MLST sequence type (ST9). All 12 clinical isolates harbored identical blaRBI. The IEF revealed that the clinical isolate produced only one β-lactamase. E. coli HB101 (pKOB23) and all 12 isolates demonstrated equally resistance to piperacillin/tazobactam (MICs, >128 μg/ml). The phenotypic confirmatory test after the initial screening test for ESBLs can discriminate β-lactamase RbiA-producing K. oxytoca from β-lactamase CTX-M-producing K. oxytoca. Twelve clinical isolates of K. oxytoca, which were recovered from an outbreak at one university hospital, had identical genotypes and produced β-lactamase RbiA that conferred resistance to piperacillin/tazobactam. In order to detect K. oxytoca isolates that produce RbiA to promote research concerning β-lactamase RbiA-producing K. oxytoca, the phenotypic confirmatory test after the initial screening test for ESBLs would be useful.

  20. Effect of IAA produced by Klebsiella oxytoca Rs-5 on cotton growth under salt stress.

    PubMed

    Liu, Yan; Shi, Zaiqiang; Yao, Lixia; Yue, Haitao; Li, Hui; Li, Chun

    2013-01-01

    Klebsiella oxytoca Rs-5 isolated with ACC (1-aminocyclopropane-1-carboxylate) deaminase activity as the sole nitrogen source could obviously promote cotton seedling growth under salt stress and produce phytohormone indole-3-acetic acid (IAA). The amount of IAA produced by the strain Rs-5 was measured, and the effect of IAA on cotton growth under salt stress was studied. Different treatments were set to treat cotton seeds with fermentation broth containing strain Rs-5 (FB), strain Rs-5, fermentation broth with bacteria removed (FB-NB), fermentation broth without bacteria or IAA (FB-NB-NI) and single IAA solutions (SI) according to the IAA concentration after strain Rs-5 culturing of 48, 72 and 120 h. The germination rate, dry weight, plant height, root length and malondialdehyde (MDA), proline and endogenous IAA content in roots were determined. The results showed that both IAA produced by strain Rs-5 and the strain were effective in promoting cotton growth under salt stress. The growth and ability to resist salt stress of cotton seedlings were increased with the enhancement of IAA concentration. The treatment of FB containing bacteria and IAA at 120 h obtained the best state of cotton growth, when the IAA content was the highest in the fermentation broth (42.14 μg·L(-1)). The germination rate, dry weight, plant height and root length were increased by 29.4%, 24.3%, 27.2% and 27.2% , respectively, compared to the saline control. The strain Rs-5 and/or IAA could obviously reduce the MDA and proline content and increase the endogenous IAA content in cotton seedlings. However, the efficacy of other components in the fermentation broth was inconspicuous.

  1. Engineering Klebsiella oxytoca for efficient 2, 3-butanediol production through insertional inactivation of acetaldehyde dehydrogenase gene.

    PubMed

    Ji, Xiao-Jun; Huang, He; Zhu, Jian-Guo; Ren, Lu-Jing; Nie, Zhi-Kui; Du, Jun; Li, Shuang

    2010-02-01

    Ethanol was a major byproduct of 2,3-butanediol (2,3-BD) fermentation by Klebsiella oxytoca ME-UD-3. In order to achieve a high efficiency of 2,3-BD production, K. oxytoca mutants deficient in ethanol formation were successfully constructed by replace the aldA gene coding for aldehyde dehydrogenase with a tetracycline resistance cassette. The results suggested that inactivation of aldA led to a significantly improved 2,3-BD production. The carbon flux to 2,3-BD was enhanced by eliminating the byproducing ethanol and at the same time reducing the accumulation of another byproduct acetoin. At last, by fed-batch culturing of the mutant, the final 2,3-BD titer up to 130 g/l with the productivity of 1.63 g/l.h and the 2,3-BD yield relative to glucose of 0.48 g/g was obtained.

  2. Isolation and characterization of a Klebsiella oxytoca strain for simultaneous azo-dye anaerobic reduction and bio-hydrogen production.

    PubMed

    Yu, Lei; Li, Wen-Wei; Lam, Michael Hon-Wah; Yu, Han-Qing; Wu, Chao

    2012-07-01

    A facultative anaerobic bacteria strain GS-4-08, isolated from an anaerobic sequence batch reactor for synthetic dye wastewater treatment, was investigated for azo-dye decolorization. This bacterium was identified as a member of Klebsiella oxytoca based on Gram staining, morphology characterization and 16S rRNA gene analysis. It exhibited a good capacity of simultaneous decolorization and hydrogen production in the presence of electron donor. The hydrogen production was less affected even at a high Methyl Orange (MO) concentration of 0.5 mM, indicating a superior tolerability of this strain to MO. This efficient bio-hydrogen production from electron donor can not only avoid bacterial inhibition due to accumulation of volatile fatty acids during MO decolorization, but also can recover considerable energy from dye wastewater.

  3. Elimination of carbon catabolite repression in Klebsiella oxytoca for efficient 2,3-butanediol production from glucose-xylose mixtures.

    PubMed

    Ji, Xiao-Jun; Nie, Zhi-Kui; Huang, He; Ren, Lu-Jing; Peng, Chao; Ouyang, Ping-Kai

    2011-02-01

    Microbial preference for glucose implies incomplete and/or slow utilization of lignocellulose hydrolysates, which is caused by the regulatory mechanism named carbon catabolite repression (CCR). In this study, a 2,3-butanediol (2,3-BD) producing Klebsiella oxytoca strain was engineered to eliminate glucose repression of xylose utilization. The crp(in) gene, encoding the mutant cyclic adenosine monophosphate (cAMP) receptor protein CRP(in), which does not require cAMP for functioning, was characterized and overexpressed in K. oxytoca. The engineered recombinant could utilize a mixture of glucose and xylose simultaneously, without CCR. The profiles of sugar consumption and 2,3-BD production by the engineered recombinant, in glucose and xylose mixtures, were examined and showed that glucose and xylose could be consumed simultaneously to produce 2,3-BD. This study offers a metabolic engineering strategy to achieve highly efficient utilization of sugar mixtures derived from the lignocellulosic biomass for the production of bio-based chemicals using enteric bacteria.

  4. Physicochemical and biological characteristics of the nanostructured polysaccharide-iron hydrogel produced by microorganism Klebsiella oxytoca.

    PubMed

    Kianpour, Sedigheh; Ebrahiminezhad, Alireza; Mohkam, Milad; Tamaddon, Ali Mohammad; Dehshahri, Ali; Heidari, Reza; Ghasemi, Younes

    2017-02-01

    There is an increasing interest in the nanostructured polysaccharide-iron hydrogel produced by Klebsiella oxytoca. Critical physicochemical and biological characteristics of these nanostructures should be revealed for biomedical applications. Accordingly, an iron reducing strain K. oxytoca, which synthesizes biogenic polysaccharide-iron hydrogel nanoparticles, known as Fe (III)-exopolysaccharide (Fe-EPS) was isolated from a mineral spring. For microbiological identification purpose 16S rRNA sequence analysis and different morphological, physiological, and biochemical characteristics of the isolate were studied. Critical physicochemical and biological characteristics of the produced Fe-EPS were evaluated using transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, X-ray crystallography (XRD), vibrating sample magnetometer (VSM). In addition, for the first time, Fe-EPS which synthesized by K. oxytoca was evaluated by dynamic light scattering (DLS), thermo gravimetric analysis (TGA), and cytotoxicity assay. TEM micrographs showed that the biogenic Fe-EPS is composed of ultra-small (about 1.8 nm) iron oxide nanoparticles (IONs) which are trapped in a polysaccharide matrix. The matrix was about 17% (w/w) of Fe-EPS total weight and provided a large negative charge of -71 mV. Interestingly, Fe-EPS showed a growth promotion effect on hepatocarcinoma cell line (Hep-G2) and 36% increase in the percentage of viability was observed by 24 h exposure to 500 μg ml(-1) Fe-EPS.

  5. Production of 2,3-butanediol by a low-acid producing Klebsiella oxytoca NBRF4.

    PubMed

    Han, Sung-Hyuk; Lee, Jung-Eun; Park, Kyungmoon; Park, Yong-Cheol

    2013-01-25

    2,3-Butanediol (2,3-BDO) is a value-added chemical with great potential for the industrial production of synthetic rubber, plastic and solvent. For microbial production of 2,3-BDO, in this study, Klebsiella oxytoca NBRF4 was constructed by chemical mutation and screening against NaBr, NaBrO(3) and fluoroacetate. Among metabolic enzymes involved in the production of lactate, acetate and 2,3-BDO, K. oxytoca NBRF4 possessed 1.2 times lower specific activities of lactate dehydrogenase and phosphotransacetylase, and 22% higher specific acetoin reductase activity than the K. oxytoca ATCC43863 control strain. A series of batch fermentations in a defined medium and application of a statistical tool of response surface method led to the determination of optimal culture conditions: 10% dissolved oxygen level, pH 4.3 and 38°C. The actual results of batch fermentation at the optimal conditions using 44 g/L glucose were coincident with the predetermined values: 14.4 g/L 2,3-BDO concentration, 0.32 g/g yield. To increase 2,3-BDO titer, fed-batch fermentation of K. oxytoca NBRF4 was performed by an intermittent feeding of 800 g/L glucose to control its concentration around 5-20 g/L in the culture broth. Finally, 34.2g/L 2,3-BDO concentration and 0.35 g/g yield were obtained without organic acid production in 70 hours of the fed-batch culture, which were 2.4 and 1.2 times higher than those of the batch fermentation using 44 g/L glucose.

  6. Enhanced production of (R,R)-2,3-butanediol by metabolically engineered Klebsiella oxytoca.

    PubMed

    Park, Jong Myoung; Rathnasingh, Chelladurai; Song, Hyohak

    2015-10-01

    Microbial fermentation produces a racemic mixture of 2,3-butanediol ((R,R)-BD, (S,S)-BD, and meso-BD), and the compositions and physiochemical properties vary from microorganism to microorganism. Although the meso form is much more difficult to transport and store because of its higher freezing point than those of the optically active forms, most microorganisms capable of producing 2,3-BD mainly yield meso-2,3-BD. Thus, we developed a metabolically engineered (R,R)-2,3-BD overproducing strain using a Klebsiella oxytoca ΔldhA ΔpflB strain, which shows an outstanding 2,3-BD production performance with more than 90 % of the meso form. A budC gene encoding 2,3-BD dehydrogenase in the K. oxytoca ΔldhA ΔpflB strain was replaced with an exogenous gene encoding (R,R)-2,3-BD dehydrogenase from Paenibacillus polymyxa (K. oxytoca ΔldhA ΔpflB ΔbudC::PBDH strain), and then its expression level was further amplified with using a pBBR1MCS plasmid. The fed-batch fermentation of the K. oxytoca ΔldhA ΔpflB ΔbudC::PBDH (pBBR-PBDH) strain with intermittent glucose feeding allowed the production of 106.7 g/L of (R,R)-2,3-BD [meso-2,3-BD, 9.3 g/L], with a yield of 0.40 g/g and a productivity of 3.1 g/L/h, which should be useful for the industrial application of 2,3-BD.

  7. Complete genome sequence of Klebsiella oxytoca E718, a New Delhi metallo-β-lactamase-1-producing nosocomial strain.

    PubMed

    Liao, Tsai-Lien; Lin, Ann-Chi; Chen, Elsa; Huang, Tzu-Wen; Liu, Yen-Ming; Chang, Ya-Hui; Lai, Jui-Fen; Lauderdale, Tsai-Ling; Wang, Jann-Tay; Chang, Shan-Chwen; Tsai, Shih-Feng; Chen, Ying-Tsong

    2012-10-01

    We report the complete genome sequence of Klebsiella oxytoca E718, a New Delhi metallo-β-lactamase-1 (NDM-1)-producing strain isolated from a renal transplant patient. The genome contains a 6,097,032-bp chromosome and two multidrug resistance plasmids with sizes of 324,906 bp and 110,781 bp.

  8. [Effect of acetic acid, furfural and 5-hydroxymethylfurfural on production of 2,3-butanediol by Klebsiella oxytoca].

    PubMed

    Wu, Jing; Cheng, Keke; Li, Wenying; Feng, Jie; Zhang, Jian'an

    2013-03-01

    To get the tolerability and consumption of Klebsiella oxytoca on major inhibitors in lignocelluloses hydrolysate, we studied the effect of acetic acid, furfural and 5-hydroxymethylfurfural on production of 2,3-butanediol by Klebsiella oxytoca. The metabolites of furfural and 5-hydroxymethylfurfural were measured. The results show that when acetic acid, furfural and 5-hydroxymethylfurfural was individually added, tolerance threshold for Klebsiella oxytoca was 30 g/L, 4 g/L and 5 g/L, respectively. Acetic acid was likely used as substrate to produce 2,3-butanediol. The yield of 2,3-butanediol increased when acetic acid concentration was lower than 30 g/L. In the fermentation, more than 70% 5-hydroxymethylfurfural was converted to 2,5-furandimethanol. All furfural and the rest of 5-hydroxymethylfurfural were metabolized by Klebsiella oxytoca. It showed that in the detoxification process of 2,3-butanediol production using lignocelluloses hydrolysate, furfural should be given priority to remove and a certain concentration of acetic acid is not need to removal.

  9. Epidemiology of Klebsiella oxytoca-associated diarrhea detected by Simmons citrate agar supplemented with inositol, tryptophan, and bile salts.

    PubMed

    Cheng, Vincent C C; Yam, Wing-Cheong; Tsang, Lee-Lee; Yau, Miranda C Y; Siu, Gilman K H; Wong, Sally C Y; Chan, Jasper F W; To, Kelvin K W; Tse, Herman; Hung, Ivan F N; Tai, Josepha W M; Ho, Pak-Leung; Yuen, Kwok-Yung

    2012-05-01

    We studied the clinical and epidemiological characteristics of Klebsiella oxytoca-associated diarrhea in hospitalized patients in Hong Kong. Between 1 November 2009 and 30 April 2011, all inositol-fermenting colonies found on Simmons citrate agar supplemented with inositol, tryptophan, and bile salts (SCITB agar) used for the culturing of diarrheal stool samples were screened by a spot indole test for K. oxytoca. The overall sensitivity of SCITB agar plus the spot indole test (93.3%) for the detection of K. oxytoca in stool samples was superior to that of MacConkey agar (63.3%), while the specificities were 100% and 60.4%, respectively. The former achieved a 23-fold reduction in the workload and cost of subsequent standard biochemical identifications. Cytotoxin production and the clonality of K. oxytoca were determined by a cell culture cytotoxicity neutralization assay using HEp-2 cells and pulsed-field gel electrophoresis (PFGE), respectively. Of 5,581 stool samples from 3,537 patients, K. oxytoca was cultured from 117/5,581 (2.1%) stool samples from 104/3,537 (2.9%) patients. Seventy-six of 104 (73.1%) patients with K. oxytoca had no copathogens in their diarrheal stool samples. Twenty-four (31.6%) of 76 patients carried cytotoxin-producing strains, which were significantly associated with antibiotic therapy after hospital admission (50% versus 21.2%; P = 0.01). Health care-associated diarrhea was found in 44 (42%) of 104 patients with K. oxytoca, but there was no epidemiological linkage suggestive of a nosocomial outbreak, and PFGE showed a diverse pattern. None of the patients with cytotoxin-producing K. oxytoca developed antibiotic-associated hemorrhagic colitis, suggesting that K. oxytoca can cause a mild disease manifesting as uncomplicated antibiotic-associated diarrhea with winter seasonality.

  10. Application of Klebsiella oxytoca immobilized cells on the treatment of cyanide wastewater.

    PubMed

    Chen, C Y; Kao, C M; Chen, S C

    2008-03-01

    Klebsiella oxytoca, isolated from cyanide-containing industrial wastewater, has been shown to be able to biodegrade cyanide to non-toxic end products. The technology of immobilized cells can be applied in biological treatment to enhance the efficiency and effectiveness of biodegradation. In this study, potassium cyanide was used as the target compound and both alginate and cellulose triacetate techniques were applied for the preparation of immobilized cells. Results from this study show that KCN can be utilized as the sole nitrogen source by K. oxytoca. The free suspension systems reveal that the cell viability was highly affected by initial KCN concentration and pH. Results show that immobilized cell systems could tolerate a higher level of KCN concentration and wider ranges of pH. In the batch experiments, the maximum KCN removal efficiencies using alginate and cellulose triacetate immobilized beads were 0.108 and 0.101mM h(-1) at pH 7, respectively. Results also indicate that immobilized system can support a higher biomass concentration. Complete KCN degradation was observed after the operation of four consecutive degradation experiments with the same batch of immobilized cells. This suggests that the activity of immobilized cells can be maintained and KCN can be used as the nitrogen source throughout KCN degradation experiments. The maximum KCN removal rates using alginate and cellulose triacetate immobilized beads in continuous-column system were 0.224 and 0.192mMh(-1) with initial KCN concentration of 3mM, respectively. Results indicate that the immobilized cells of K. oxytoca would be applicable to the treatment of cyanide-containing wastewaters.

  11. Intracellular azo decolorization is coupled with aerobic respiration by a Klebsiella oxytoca strain.

    PubMed

    Yu, Lei; Zhang, Xiao-Yu; Xie, Tian; Hu, Jin-Mei; Wang, Shi; Li, Wen-Wei

    2015-03-01

    Reduction of azo dye methyl red coupled with aerobic respiration by growing cultures of Klebsiella oxytoca GS-4-08 was investigated. In liquid media containing dye and 0.6 % glucose in a mineral salts base, 100 mg l(-1) of the dye are completely removed in 3 h under shaking conditions. The dye cannot be aerobically decolorized by strain GS-4-08 without extra carbon sources, indicating a co-metabolism process. Higher initial dye concentration prolonged the lag phase of the cell growth, but final cell concentrations of each batches reached a same level with range from 6.3 to 7.6 mg l(-1) after the dye adaption period. This strain showed stronger dye tolerance and decolorization ability than many reported strains. Furthermore, a new intracellular oxygen-insensitive azoreductase was isolated from this strain, and the specific activity of enzyme was 0.846 and 0.633 U mg(-1) protein in the presence of NADH and NADPH, respectively. N,N dimethyl-p-phenylenediamine and anthranilic acid were stoichiometrically released from MR dye, indicating the breakage of azo bonds accounts for the intracellular decolorization. Combining the characteristics of azoreductase, the stoichiometry of EMP, and TCA cycle, the electron transfer chain theory of aerobic respiration, and the possible mechanism of aerobic respiration coupled with azo reduction by K. oxytoca GS-4-08 are proposed. This study is expected to provide a sound theoretical basis for the development of the K. oxytoca strain in aerobic process for azo dye containing wastewaters.

  12. Purine utilization by Klebsiella oxytoca M5al: genes for ring-oxidizing and -opening enzymes.

    PubMed

    Pope, Scott D; Chen, Li-Ling; Stewart, Valley

    2009-02-01

    The enterobacterium Klebsiella oxytoca uses a variety of inorganic and organic nitrogen sources, including purines, nitrogen-rich compounds that are widespread in the biosphere. We have identified a 23-gene cluster that encodes the enzymes for utilizing purines as the sole nitrogen source. Growth and complementation tests with insertion mutants, combined with sequence comparisons, reveal functions for the products of these genes. Here, we report our characterization of 12 genes, one encoding guanine deaminase and the others encoding enzymes for converting (hypo)xanthine to allantoate. Conventionally, xanthine dehydrogenase, a broadly distributed molybdoflavoenzyme, catalyzes sequential hydroxylation reactions to convert hypoxanthine via xanthine to urate. Our results show that these reactions in K. oxytoca are catalyzed by a two-component oxygenase (HpxE-HpxD enzyme) homologous to Rieske nonheme iron aromatic-ring-hydroxylating systems, such as phthalate dioxygenase. Our results also reveal previously undescribed enzymes involved in urate oxidation to allantoin, catalyzed by a flavoprotein monooxygenase (HpxO enzyme), and in allantoin conversion to allantoate, which involves allantoin racemase (HpxA enzyme). The pathway also includes the recently described PuuE allantoinase (HpxB enzyme). The HpxE-HpxD and HpxO enzymes were discovered independently by de la Riva et al. (L. de la Riva, J. Badia, J. Aguilar, R. A. Bender, and L. Baldoma, J. Bacteriol. 190:7892-7903, 2008). Thus, several enzymes in this K. oxytoca purine utilization pathway differ from those in other microorganisms. Isofunctional homologs of these enzymes apparently are encoded by other species, including Acinetobacter, Burkholderia, Pseudomonas, Saccharomyces, and Xanthomonas.

  13. Genome sequence of Klebsiella oxytoca 11492-1, a nosocomial isolate possessing a FOX-5 AmpC β-lactamase.

    PubMed

    Hazen, Tracy H; Robinson, Gwen L; Harris, Anthony D; Rasko, David A; Johnson, J Kristie

    2012-06-01

    Klebsiella oxytoca strain 11492-1 was isolated from a perianal swab culture from a patient at the University of Maryland Medical Center in 2005. The K. oxytoca 11492-1 draft genome contains multiple antibiotic resistance genes, including a FOX-5 AmpC β-lactamase encoded on a large IncA/C plasmid.

  14. Klebsiella oxytoca-producing IMP-1 Detected as the First Strain of Carbapenem-resistant Enterobacteriaceae in Our Hospital.

    PubMed

    Hagiya, Hideharu; Ogawa, Hiroko; Takahashi, Yusuke; Yamamoto, Akira; Otsuka, Fumio

    2015-01-01

    We herein report a case of Klebsiella oxytoca-producing IMP-1 that was detected as a first isolate of carbapenem-resistant Enterobacteriaceae (CRE) at our facility. Since K. oxytoca is an uncommon strain for CRE, we speculated that the resistant organism had already spread out inside the hospital. Metallo-β-lactamases promotes antibiotic resistance in Enterobacteriaceae, which potentially yields problematic issues in clinical settings. Active surveillance of antibiotic resistant strains is important and should be repeatedly highlighted. Furthermore, appropriate methods should be established to detect highly resistant strains.

  15. Characterization and cloning of oxygen-tolerant hydrogenase from Klebsiella oxytoca HP1.

    PubMed

    Wu, Xiaobing; Liang, Yi; Li, Qianyi; Zhou, Juan; Long, Minnan

    2011-04-01

    Hydrogenase from a hot spring bacterium Klebsiella oxytoca HP1 was purified and found to have a specific activity of 199.8 U/mg of protein and a yield of 7.3%. The purified enzyme was determined to consist of six subunits (65, 33, 28, 23, 21 and 18 kDa), similar to hydrogenase-3 from Escherichia coli, and therefore it was named Hyd3. The enzyme displayed remarkable oxygen tolerance. For the purified enzyme, 50% maximal activity was maintained following incubation for 24 h in air at room temperature. The hydrogenase gene cluster (hyc) was cloned and found to consist of hycD, hycE, hycF, hycdG, hycH and hycI genes. hycE and hycG genes encode for the large and small subunit of the hydrogenase, respectively. A hycE gene deletion mutant, ΔhycE, was constructed for elucidating the function of the hyc-operon in hydrogen metabolism. Compared with the wild type strain HP1, the mutant strain showed a dramatic decrease in hydrogen production in the presence of formate, sodium pyruvate and glucose under O(2)-stressed conditions, while substantial activity was detected under anaerobic conditions. This strongly suggests that K. oxytoca HP1 carries a number of hydrogenases or hydrogen metabolic pathways independently of Hyd3. However, Hyd3 is the main factor responsible for hydrogen production under O(2) stress conditions.

  16. Genetic control of nitrate assimilation in Klebsiella oxytoca. Final technical report

    SciTech Connect

    Stewart, Valley J.

    2001-04-01

    Some microorganisms can use nitrate as the sole source of nitrogen for biosynthesis. This project focused on the bacterium Klebsiella oxytoca, an enterobacterium found in soil and water. Mutagenesis and molecular cloning identified the nasFEDCBA operon encoding enzymes for the uptake and reduction of nitrate and nitrite to ammonium, and the adjacent nasR regulatory gene. Analysis of nasF operon expression revealed that transcription is activated by the Ntr (general nitrogen regulation ) system in response to nitrogen limitation. Transcription antitermination control in response to nitrate and nitrite is mediated by the NasR protein. Additional work established that the NasR protein is an RNA-binding protein that interacts with nasF operon leader RNA to control transcription readthrough.

  17. Enhancement of 2,3-butanediol production by Klebsiella oxytoca PTCC 1402.

    PubMed

    Anvari, Maesomeh; Safari Motlagh, Mohammad Reza

    2011-01-01

    Optimal operating parameters of 2,3-Butanediol production using Klebsiella oxytoca under submerged culture conditions are determined by using Taguchi method. The effect of different factors including medium composition, pH, temperature, mixing intensity, and inoculum size on 2,3-butanediol production was analyzed using the Taguchi method in three levels. Based on these analyses the optimum concentrations of glucose, acetic acid, and succinic acid were found to be 6, 0.5, and 1.0 (% w/v), respectively. Furthermore, optimum values for temperature, inoculum size, pH, and the shaking speed were determined as 37°C, 8 (g/L), 6.1, and 150 rpm, respectively. The optimal combinations of factors obtained from the proposed DOE methodology was further validated by conducting fermentation experiments and the obtained results revealed an enhanced 2,3-Butanediol yield of 44%.

  18. Iron-binding characterization and polysaccharide production by Klebsiella oxytoca strain isolated from mine acid drainage

    PubMed Central

    Baldi, F; Marchetto, D; Battistel, D; Daniele, S; Faleri, C; De Castro, C; Lanzetta, R

    2009-01-01

    Aims: To investigate Klebsiella oxytoca strain BAS-10 growth on ferric citrate under anaerobic conditions for exopolysaccharide (EPS) production and localization on cell followed by the purification and the EPS determination of the iron-binding stability constant to EPS or biotechnological applications. Methods and Results: Klebsiella oxytoca ferments ferric citrate under anaerobic conditions and produces a ferric hydrogel, whereas ferrous ions were formed in solution. During growth, cells precipitate and a hydrogel formation was observed: the organic material was constituted of an EPS bound to Fe(III) ions, this was found by chemical analyses of the iron species and transmission electron microscopy of the cell cultures. Iron binding to EPS was studied by cyclic voltammetric measurements, either directly on the hydrogel or in an aqueous solutions containing Fe(III)-citrate and purified Fe(III)-EPS. From the voltammetric data, the stability constant for the Fe(III)-EPS complex can be assumed to have values of approx. 1012–1013. It was estimated that this is higher than for the Fe(III)-citrate complex. Conclusions: The production of Fe(III)-EPS under anaerobic conditions is a strategy for the strain to survive in mine drainages and other acidic conditions. This physiological feature can be used to produce large amounts of valuable Fe(III)-EPS, starting from a low cost substrate such as Fe(III)-citrate. Significant and Impact of the Study: The data herein demonstrates that an interesting metal-binding molecule can be produced as a novel catalyst for a variety of potential applications and the EPS itself is a valuable source for rhamnose purification. PMID:19508299

  19. Mechanism of resistance and antibacterial susceptibility in extended-spectrum β-lactamase phenotype Klebsiella pneumoniae and Klebsiella oxytoca isolated between 2000 and 2010 in Japan.

    PubMed

    Sato, Takafumi; Hara, Takafumi; Horiyama, Tsukasa; Kanazawa, Sachi; Yamaguchi, Takahiro; Maki, Hideki

    2015-05-01

    Clinical isolates of Klebsiella pneumoniae and Klebsiella oxytoca collected from 20 Japanese medical facilities between 2000 and 2010 were analysed to evaluate the mechanisms of resistance and antibacterial susceptibilities to 14 antimicrobials. Overall, eight of 484 (1.6%) K. pneumoniae and 19 of 359 (5.3%) K. oxytoca were determined to be extended-spectrum β-lactamase (ESBL) phenotype isolates, and the identified ESBLs amongst the K. pneumoniae isolates were CTX-M-2, -3, -14 and -15, and SHV-12. In contrast, overproduction of chromosomal β-lactamase OXY-2, which was due to a distinct mutation at the - 10 promoter region of this gene, conferred the ESBL phenotype to all the K. oxytoca isolates except one. Based on the Clinical and Laboratory Standards Institute breakpoints, all the ESBL phenotype K. pneumoniae were susceptible to doripenem, flomoxef, moxalactam (latamoxef), cefmetazole and tazobactam/piperacillin, whereas the ESBL phenotype K. oxytoca were susceptible to ceftazidime and ceftibuten in addition to the above, with the exception of tazobactam/piperacillin. Amongst the oral antimicrobials, ceftibuten was relatively effective against both ESBL phenotype Klebsiella species compared with levofloxacin and amoxicillin/clavulanic acid.

  20. The higher disinfectant resistance of nosocomial isolates of Klebsiella oxytoca: how reliable are indicator organisms in disinfectant testing?

    PubMed

    Gebel, J; Sonntag, H-G; Werner, H-P; Vacata, V; Exner, M; Kistemann, T

    2002-04-01

    The Children's Clinic in Giessen, Germany recently reported several severe infections with Klebsiella oxytoca resulting in deaths of two neonates. The putative source of the infections was a contaminated infusion solution. The resistance to disinfectant of the K. oxytoca isolates was investigated in three independent laboratories and was indeed found to be significantly increased. Comparative tests with standard strains of K. oxytoca and other recommended bacterial surrogates showed the disinfection procedures used were fully effective. The higher resistance of the nosocomial isolates may have developed due to improper handling and storage of the cleaning utensils. This report describes the events and draws conclusions concerning the use of disinfectants, the treatment of cleaning utensils, the reliability of procedures for testing disinfectants, and suggests additional measures.

  1. Final Technical Report: Genetic Control of Nitrogen Assimilation in Klebsiella oxytoca.

    SciTech Connect

    Valley Stewart

    2007-03-07

    Klebsiella oxytoca, an enterobacterium closely related to Escherichia coli and amenable to molecular genetic analysis, is a long-established model organism for studies of bacterial nitrogen assimilation. Our work concerned utilization of purines, nitrogen-rich compounds that are widespread in the biosphere. This project began with our observation that molybdenum cofactor (chlorate-resistant) mutants can use (hypo)xanthine as sole nitrogen source (Garzón et al., J. Bacteriol. 174:6298, 1992). Since xanthine dehydrogenase is a molybdoenzyme, Klebsiella must use an alternate route for (hypo)xanthine catabolsim. We identified and characterized a cluster of 22 genes that encode the enzymes, permeases and regulators for utilizing hypoxanthine and xanthine as sole nitrogen source. (Hypoxanthine and xanthine arise from deamination of adenine and guanine, respectively.) Growth and complementation tests with insertion mutants, combined with protein sequence comparisons, allow us to assign probable functions for the products of these genes and to deduce the overall pathway. We present genetic evidence that the first two enzymes for the Klebsiella purine utilization pathway have been recruited from pathways involved in catabolism of aromatic compounds. The first, HxaAB enzyme catalyzing (hypo)xanthine oxidation, is related to well-studied aromatic ring hydroxylating oxygenases such as phthalate dioxygenase. The second, HxbA enzyme catalyzing urate hydroxylation, is related to single-component monooxygenases. Thus, the Klebsiella purine utilization pathway has likely experienced non-orthologous gene displacement, substituting these oxygenases for the conventional enzymes, xanthine dehydrogenase and uricase. We also present evidence that transcription of the hxaAB operon is subject to dual regulation: global general nitrogen regulation (Ntr) through an unknown mechanism, and (hypo)xanthine induction mediated by a LysR-type activator.

  2. Outbreak of extended-spectrum β-lactamase-producing Klebsiella oxytoca infections associated with contaminated handwashing sinks(1).

    PubMed

    Lowe, Christopher; Willey, Barbara; O'Shaughnessy, Anna; Lee, Wayne; Lum, Ming; Pike, Karen; Larocque, Cindy; Dedier, Helen; Dales, Lorraine; Moore, Christine; McGeer, Allison

    2012-08-01

    Klebsiella oxytoca is primarily a health care-associated pathogen acquired from environmental sources. During October 2006-March 2011, a total of 66 patients in a hospital in Toronto, Ontario, Canada, acquired class A extended-spectrum β-lactamase-producing K. oxytoca with 1 of 2 related pulsed-field gel electrophoresis patterns. New cases continued to occur despite reinforcement of infection control practices, prevalence screening, and contact precautions for colonized/infected patients. Cultures from handwashing sinks in the intensive care unit yielded K. oxytoca with identical pulsed-field gel electrophoresis patterns to cultures from the clinical cases. No infections occurred after implementation of sink cleaning 3×/day, sink drain modifications, and an antimicrobial stewardship program. In contrast, a cluster of 4 patients infected with K. oxytoca in a geographically distant medical ward without contaminated sinks was contained with implementation of active screening and contact precautions. Sinks should be considered potential reservoirs for clusters of infection caused by K. oxytoca.

  3. First Description of KPC-2-Producing Klebsiella oxytoca Isolated from a Pediatric Patient with Nosocomial Pneumonia in Venezuela

    PubMed Central

    Labrador, Indira

    2014-01-01

    During the last decade, carbapenem resistance has emerged among clinical isolates of the Enterobacteriaceae family. This has been increasingly attributed to the production of β-lactamases capable of hydrolyzing carbapenems. Among these enzymes, Klebsiella pneumoniae carbapenemases (KPCs) are the most frequently and clinically significant class-A carbapenemases. In this report, we describe the first nosocomial KPC-2-producing K. oxytoca isolated from a pediatric patient with pneumonia admitted to the intensive care unit at The Andes University Hospital, Mérida, Venezuela. This strain was resistant to several antibiotics including imipenem, ertapenem, and meropenem but remained susceptible to ciprofloxacin, colistin, and tigecycline. Conjugation assays demonstrated the transferability of all resistance determinants, except aminoglycosides. The isolate LMM-SA26 carried a ~21 kb conjugative plasmid that harbored the blaKPC-2, blaCTX-M-8, and blaTEM-15 genes. Although carbapenem resistance in the Enterobacteriaceae is still unusual in Venezuela, KPCs have a great potential to spread due to their localization on mobile genetic elements. Therefore, rapid detection of KPC-carrying bacteria with phenotypic and confirmatory molecular tests is essential to establish therapeutic options and effective control measures. PMID:25405043

  4. Selective production of 2,3-butanediol and acetoin by a newly isolated bacterium Klebsiella oxytoca M1.

    PubMed

    Cho, Sukhyeong; Kim, Kyung Duk; Ahn, Jae-Hyung; Lee, Jinwon; Kim, Seon-Won; Um, Youngsoon

    2013-08-01

    A newly isolated bacterium, designated as Klebsiella oxytoca M1, produced 2,3-butanediol (2,3-BDO) or acetoin selectively as a major product depending on temperature in a defined medium. K. oxytoca M1 produced 2,3-BDO mainly (0.32~0.34 g/g glucose) at 30 °C while acetoin was a major product (0.32~0.38 g/g glucose) at 37 °C. To investigate factors affecting product profiles according to temperature, the expression level of acetoin reductase (AR) that catalyzes the conversion of acetoin to 2,3-BDO was analyzed using crude protein extracted from K. oxytoca M1 grown at 30 and 37 °C. The AR expression at 37 °C was 12.8-fold lower than that at 30 °C at the stationary phase and reverse transcription PCR (RT-PCR) analysis of the budC (encoding AR) was also in agreement with the AR expression results. When AR was overexpressed using K. oxytoca M1 harboring pUC18CM-budC, 2,3-BDO became a major product at 37 °C, indicating that the AR expression level was a key factor determining the major product of K. oxytoca M1 at 37 °C. The results in this study demonstrate the feasibility of using K. oxytoca M1 for the production of not only 2,3-BDO but also acetoin as a major product.

  5. Detection of the Klebsiella pneumoniae carbapenemase type 2 Carbapenem-hydrolyzing enzyme in clinical isolates of Citrobacter freundii and K. oxytoca carrying a common plasmid.

    PubMed

    Rasheed, J Kamile; Biddle, James W; Anderson, Karen F; Washer, Laraine; Chenoweth, Carol; Perrin, John; Newton, Duane W; Patel, Jean B

    2008-06-01

    The Klebsiella pneumoniae carbapenemase (KPC) was detected in carbapenem-resistant isolates of Citrobacter freundii and Klebsiella oxytoca recovered from different patients in a Michigan hospital. Restriction analysis and hybridization with a KPC-specific probe showed the bla(KPC-2) genes of these two genera of the family Enterobacteriaceae are carried on a common plasmid.

  6. Retrospective analysis of the genetic diversity of Klebsiella oxytoca isolated in Poland over a 50-year period.

    PubMed

    Stojowska, K; Krawczyk, B; Kałuzewski, S; Kur, J

    2009-10-01

    Population genetics analyses and determination of the phylogenetic relationships between strains have proven to be extremely useful approaches, enabling deeper insights into the epidemiological pattern of bacterial species. There is no longitudinal data describing the molecular epidemiology of Klebsiella oxytoca strains that are opportunistic pathogens responsible for an increasing number of multi-resistant infections in hospitals. The aim of the present study was to assess the genetic diversity of K. oxytoca strains over a 50-year period using internal transcribed spacer polymerase chain reaction (ITS-PCR) and PCR MP (ang. PCR melting profiles) genotyping methods on a large collection of strains isolated from the patients of several hospitals in Poland. The phylogenetic analysis based on ITS-PCR exhibited six distinct branches. Two main groups, KoX and KoY, with four and two sub-groups within KoX and KoY, respectively, have been identified. Typing by the PCR MP method showed a higher level of genetic diversity. However, all K. oxytoca strains were also divided into six genotype groups (KoA, KoB, KoC, KoD, KoE and KoF). In conclusion, we found that the ITS-PCR and PCR MP methods are useful for the phylogenetic delineation of genetic groups in K. oxytoca.

  7. Effects of nano zero-valent iron on Klebsiella oxytoca and stress response.

    PubMed

    Saccà, Maria Ludovica; Fajardo, Carmen; Nande, Mar; Martín, Margarita

    2013-11-01

    Nano zero-valent iron (NZVI) is a new option for contaminated soil and groundwater treatment, despite little is known on their impact on environmental microorganisms. Klebsiella oxytoca K5 strain, isolated from the NZVI-treated soil, was used to investigate the bacterial, phenotypical and molecular response to commercial NZVI exposure. Cytotoxicity assays at three NZVI concentrations (1, 5 and 10 mg mL(-1)) suggested a negligible bacteriostatic effect and the lack of bactericidal effect. Structural changes were analysed by electronic microscopy. Scanning electron microscopy revealed the presence of NZVI around some bacterial cells, but no apparent morphological changes were seen. NZVI attachment to the cell surface was confirmed by transmission electron microscopy, although most of them were not affected. A proteomic approach (two-dimensional electrophoresis, matrix-assisted laser desorption ionization time-of-flight mass spectrometry) was used to investigate NZVI impact. For the first time to our knowledge, results revealed that exposure of a soil bacterium to NZVI resulted in the overproduction of tryptophanase, associated with oxidative stress response. K5 may set up an adaptative stress response involving indole as a signal molecule to inform the bacterial population about environmental changes. These findings would improve knowledge on the molecular mechanisms underlying bacterial response to NZVI exposure.

  8. Metabolic engineering of a novel Klebsiella oxytoca strain for enhanced 2,3-butanediol production.

    PubMed

    Kim, Duk-Ki; Rathnasingh, Chelladurai; Song, Hyohak; Lee, Hee Jong; Seung, Doyoung; Chang, Yong Keun

    2013-08-01

    Fermentative 2,3-butanediol (2,3-BD) production has been receiving increasing interest for its potential as a platform chemical intended for the production of synthetic rubbers, plastics, and solvents. In this study, Klebsiella oxytoca GSC 12206, a 2,3-BD native hyper-producing and nonpathogenic bacterium, was isolated from a cattle farm. Since this isolate produced a significant amount of lactic acid along with 2,3-BD, its mutant deficient in lactic acid formation was constructed by disrupting the ldhA gene which encodes lactate dehydrogenase. The ldhA gene was deleted precisely by using the pKGS plasmid. When compared to the wild-type strain, the mutant deleted with the ldhA gene in glucose fermentation resulted in an increase of 54%, 13%, 60%, and 78% of 2,3-BD titer, productivity, yield, and selectivity, respectively. A fed-batch fermentation by this mutant with intermittent glucose feeding produced 115 g/L of 2,3-BD with an yield and productivity of 0.41 g 2,3-BD per g glucose and 2.27 g/L h, respectively, indicating the usefulness for the industrial production of 2,3-BD.

  9. First report of Klebsiella oxytoca strain coproducing KPC-2 and IMP-8 carbapenemases.

    PubMed

    Li, Bin; Sun, Jing-Yong; Liu, Qing-Zhong; Han, Li-Zhong; Huang, Xin-Hong; Ni, Yu-Xing

    2011-06-01

    The study shows for the first time the presence of the Klebsiella oxytoca strain fp10 coproducing plasmid-mediated KPC-2 and IMP-8 carbapenemases. The strain was obtained from the fecal sample of an inpatient and showed high-level resistance to imipenem and ertapenem (MICs > 32 μg/ml). Conjugation experiments demonstrated the transferability of the carbapenem-resistant determinants. The results of plasmid analysis and Southern hybridization revealed that the bla(KPC-2) gene was located on transferable plasmid pFP10-1 (∼54 kb), whereas the bla(IMP-8) gene was on transferable plasmid pFP10-2 (∼180 kb). Analysis of the genetic environment of these two genes has demonstrated that ISKpn6 and ISKpn8 are involved in the spread of the bla(KPC-2) gene, while the transposable elements IS26, intI1, and tniC might contribute to the dissemination of the bla(IMP-8) gene. The chimera of several transposon-associated elements indicated a novel genetic environment of IMP-type metallo-β-lactamase gene in Enterobacteriaceae from China.

  10. XAS analysis of a nanostructured iron polysaccharide produced anaerobically by a strain of Klebsiella oxytoca.

    PubMed

    Arčon, Iztok; Piccolo, Oreste; Paganelli, Stefano; Baldi, Franco

    2012-10-01

    A strain of Klebsiella oxytoca, isolated from acid pyrite-mine drainage, characteristically produces a ferric hydrogel, consisting of branched heptasaccharide repeating units exopolysaccharide (EPS), with metal content of 36 wt%. The high content of iron in the EPS matrix cannot be explained by a simple ferric ion bond to the sugar skeleton. The bio-generated Fe-EPS is investigated by X-ray absorption spectroscopy. Fe K-edge XANES analysis shows that iron is mostly in trivalent form, with a non-negligible amount of Fe(2+) in the structure. The Fe EXAFS results indicate that iron in the sample is in a mineralized form, prevalently in the form of nano-sized particles of iron oxides/hydroxides, most probably a mixture of different nano-crystalline forms. TEM shows that these nanoparticles are located in the interior of the EPS matrix, as in ferritin. The strain produces Fe-EPS to modulate Fe-ions uptake from the cytoplasm to avoid iron toxicity under anaerobic conditions. This microbial material is potentially applicable as iron regulator.

  11. Pilotin-secretin recognition in the type II secretion system of Klebsiella oxytoca.

    PubMed

    Tosi, Tommaso; Nickerson, Nicholas N; Mollica, Luca; Jensen, Malene Ringkjøbing; Blackledge, Martin; Baron, Bruno; England, Patrick; Pugsley, Anthony P; Dessen, Andréa

    2011-12-01

    A crucial aspect of the functionality of bacterial type II secretion systems is the targeting and assembly of the outer membrane secretin. In the Klebsiella oxytoca type II secretion system, the lipoprotein PulS, a pilotin, targets secretin PulD monomers through the periplasm to the outer membrane. We present the crystal structure of PulS, an all-helical bundle that is structurally distinct from proteins with similar functions. Replacement of valine at position 42 in a charged groove of PulS abolished complex formation between a non-lipidated variant of PulS and a peptide corresponding to the unfolded region of PulD to which PulS binds (the S-domain), in vitro, as well as PulS function in vivo. Substitutions of other residues in the groove also diminished the interaction with the S-domain in vitro but exerted less marked effects in vivo. We propose that the interaction between PulS and the S-domain is maintained through a structural adaptation of the two proteins that could be influenced by cis factors such as the fatty acyl groups on PulS, as well as periplasmic trans-acting factors, which represents a possible paradigm for chaperone-target protein interactions.

  12. Production of 2,3-butanediol from acid hydrolysates of Jatropha hulls with Klebsiella oxytoca.

    PubMed

    Jiang, Li-Qun; Fang, Zhen; Guo, Feng; Yang, Lin-bin

    2012-03-01

    Jatropha hulls were successfully for the first time used as raw materials for the production of 2,3-butanediol via dilute sulfuric acid hydrolysis and fermentation with Klebsiella oxytoca. Two-step hydrolysis was used to effectively hydrolyze the hulls at 150°C after pretreatment. In the first-step, hemicellulose was hydrolyzed under mild conditions (0.5h, 1.5% acid) to avoid secondary decomposition. The remained cellulose was further hydrolyzed in the second-step under severer conditions (1h, 4% acid). After hydrolysis, total hydrolysis yield was 64%, which was much higher than that (37%) from the first-step. Maximum yields of 2,3-butanediol and acetoin in flask experiments were 35.6% and 41.4% from the hydrolysates of the first- and second-step hydrolysis, equivalent to 71.2% and 82.8% of the theoretical values, respectively. Similar yields were obtained in a controlled bioreactor but with higher productivities. Jatropha hulls are attractive raw materials for the production of 2,3-butanediol with high yield.

  13. In silico aided metabolic engineering of Klebsiella oxytoca and fermentation optimization for enhanced 2,3-butanediol production.

    PubMed

    Park, Jong Myoung; Song, Hyohak; Lee, Hee Jong; Seung, Doyoung

    2013-09-01

    Klebsiella oxytoca naturally produces a large amount of 2,3-butanediol (2,3-BD), a promising bulk chemical with wide industrial applications, along with various byproducts. In this study, the in silico gene knockout simulation of K. oxytoca was carried out for 2,3-BD overproduction by inhibiting the formation of byproducts. The knockouts of ldhA and pflB genes were targeted with the criteria of maximization of 2,3-BD production and minimization of byproducts formation. The constructed K. oxytoca ΔldhA ΔpflB strain showed higher 2,3-BD yields and higher final concentrations than those obtained from the wild-type and ΔldhA strains. However, the simultaneous deletion of both genes caused about a 50 % reduction in 2,3-BD productivity compared with K. oxytoca ΔldhA strain. Based on previous studies and in silico investigation that the agitation speed during 2,3-BD fermentation strongly affected cell growth and 2,3-BD synthesis, the effect of agitation speed on 2,3-BD production was investigated from 150 to 450 rpm in 5-L bioreactors containing 3-L culture media. The highest 2,3-BD productivity (2.7 g/L/h) was obtained at 450 rpm in batch fermentation. Considering the inhibition of acetoin for 2,3-BD production, fed-batch fermentations were performed using K. oxytoca ΔldhA ΔpflB strain to enhance 2,3-BD production. Altering the agitation speed from 450 to 350 rpm at nearly 10 g/L of acetoin during the fed-batch fermentation allowed for the production of 113 g/L 2,3-BD, with a yield of 0.45 g/g, and for the production of 2.1 g/L/h of 2,3-BD.

  14. Cytotoxic effects of Klebsiella oxytoca strains isolated from patients with antibiotic-associated hemorrhagic colitis or other diseases caused by infections and from healthy subjects.

    PubMed

    Joainig, Martina M; Gorkiewicz, Gregor; Leitner, Eva; Weberhofer, Paul; Zollner-Schwetz, Ines; Lippe, Irmgard; Feierl, Gebhard; Krause, Robert; Hinterleitner, Thomas; Zechner, Ellen L; Högenauer, Christoph

    2010-03-01

    Antibiotic-associated hemorrhagic colitis (AAHC) is associated with Klebsiella oxytoca. This study analyzed whether cytotoxic properties are linked to specific subtypes of K. oxytoca. Klebsiella isolates from stools of AAHC patients, healthy carriers, and diarrhea patients as well as from infections of other organs were investigated. Cytotoxic effects on human epithelial cells were limited to the species K. oxytoca and were not detectable for any other Klebsiella species. Isolates from AAHC patients and from stools showed the highest proportion of cytotoxic strains. Urinary or respiratory tract isolates exhibited no cytotoxicity. Macrorestriction profiling of strains revealed no genetic relationships of AAHC isolates or the cytotoxic phenotype but identified that different K. oxytoca strains with different cytotoxic behaviors may be prevalent in the same AAHC patient. Under laboratory conditions, cytotoxicity was maximally effective after exponential bacterial growth and then declined despite the continued viability of K. oxytoca cells in culture. Given its capacity to induce AAHC and that a high proportion of stool isolates tested cytotoxin positive, we argue that K. oxytoca should be considered an opportunistic pathogen if detected in stools. The ability to induce disease after antibiotic treatment most likely represents an overgrowth of the toxin-producing bacterium due to an alteration of the normal colonic microflora.

  15. Complete genome sequence of Klebsiella oxytoca M1, isolated from Manripo area of South Korea.

    PubMed

    Shin, Sang Heum; Roh, Hanseong; Kim, Juhyeok; Cho, Sukhyeong; Um, Youngsoon; Lee, Jinwon; Ryu, Yeon-Woo; Chong, Hyonyong; Yang, Kap-Seok

    2015-03-20

    Here we report the full genome sequence of Klesiella oxytoca M1, isolated from Manripo area of South Korea. The strain K. oxytoca M1 is able to produce either 2,3-butanediol or acetoin selectively by controlling the pH and temperature.

  16. Crystal structure of a novel two domain GH78 family α-rhamnosidase from Klebsiella oxytoca with rhamnose bound.

    PubMed

    O'Neill, Ellis C; Stevenson, Clare E M; Paterson, Michael J; Rejzek, Martin; Chauvin, Anne-Laure; Lawson, David M; Field, Robert A

    2015-09-01

    The crystal structure of the GH78 family α-rhamnosidase from Klebsiella oxytoca (KoRha) has been determined at 2.7 Å resolution with rhamnose bound in the active site of the catalytic domain. Curiously, the putative catalytic acid, Asp 222, is preceded by an unusual non-proline cis-peptide bond which helps to project the carboxyl group into the active centre. This KoRha homodimeric structure is significantly smaller than those of the other previously determined GH78 structures. Nevertheless, the enzyme displays α-rhamnosidase activity when assayed in vitro, suggesting that the additional structural domains found in the related enzymes are dispensible for function.

  17. Characterization of a novel IMP-28 metallo-β-lactamase from a Spanish Klebsiella oxytoca clinical isolate.

    PubMed

    Pérez-Llarena, Francisco José; Fernández, Ana; Zamorano, Laura; Kerff, Frédéric; Beceiro, Alejandro; Aracil, Belén; Cercenado, Emilia; Miro, Elisenda; Oliver, Antonio; Oteo, Jesús; Navarro, Ferran; Bou, Germán

    2012-08-01

    An isolate of Klebsiella oxytoca carrying a novel IMP metallo-β-lactamase was discovered in Madrid, Spain. The bla(IMP-28) gene is part of a chromosomally located class I integron. The IMP-28 k(cat)/K(m) values for ampicillin, ceftazidime, and cefepime and, to a lesser extent, imipenem and meropenem, are clearly lower than those of IMP-1. The His306Gln mutation may induce important modifications of the L3 loop and thus of substrate accessibility and hydrolysis and be the main reason for this behavior.

  18. Complete sequences of two plasmids in a blaNDM-1-positive Klebsiella oxytoca isolate from Taiwan.

    PubMed

    Huang, Tzu-Wen; Wang, Jann-Tay; Lauderdale, Tsai-Ling; Liao, Tsai-Lien; Lai, Jui-Fen; Tan, Mei-Chen; Lin, Ann-Chi; Chen, Ying-Tsong; Tsai, Shih-Feng; Chang, Shan-Chwen

    2013-08-01

    Genetic determinants of a bla(NDM-1)-positive, multidrug-resistant bacterial isolate that caused active infection was investigated by DNA sequencing. Two plasmids, pKOX_NDM1 and pKOX-R1, were identified for the Klebsiella oxytoca strain E718. Sequence annotation revealed a bla(NDM-1) gene in pKOX_NDM1 and two extended-spectrum β-lactamase producers (bla(CTX-M-3) and blaSHV-12) and a wide array of resistance genes in pKOX-R1. These findings highlight the difficulty in treating multidrug-resistant bacterial infections and the potential danger of emerging resistant enterobacteria.

  19. Analysis of plasmid-mediated multidrug resistance in Escherichia coli and Klebsiella oxytoca isolates from clinical specimens in Japan.

    PubMed

    Ode, Takashi; Saito, Ryoichi; Kumita, Wakako; Sato, Kenya; Okugawa, Shu; Moriya, Kyoji; Koike, Kazuhiko; Okamura, Noboru

    2009-10-01

    This study investigated the relationship of plasmid-mediated quinolone resistance (PMQR) and aminoglycoside resistance among oxyimino-cephalosporin-resistant Escherichia coli (n=46) and Klebsiella oxytoca (n=28) clinical isolates in Japan. Seventy-three isolates appeared to produce an extended-spectrum beta-lactamase (ESBL) and one K. oxytoca isolate produced IMP-1 metallo-beta-lactamase (MBL). Polymerase chain reaction (PCR) and sequencing confirmed that eight CTX-M-9/SHV-12-producing isolates, one IMP-1-producing K. oxytoca isolate, and six ESBL-positive E. coli isolates respectively possessed PMQR genes qnrA1, qnrB6, and aac(6')-Ib-cr. All qnr-positive isolates also carried either aac(6')-Ib or aac(6')-IIc aminoglycoside acetyltransferase genes. Resistance determinants to beta-lactams, quinolones and aminoglycosides were co-transferred with a plasmid of ca. 140 kb. The qnrA1 gene was located downstream of insertion sequence ISCR1 in complex class 1 integrons. A novel qnrA1-carrying class 1 integron with the cassette arrangement aac(6')-IIc-aadA2 as well as a unique class 1 integron with bla(IMP-1)-aac(6')-IIc cassettes on the plasmid carrying qnrB6 were found in K. oxytoca isolates. We describe the identification of qnrB6 and aac(6')-Ib-cr and the close association of qnr with aac(6')-Ib and aac(6')-IIc for the first time in clinical isolates producing ESBL or MBL in Japan.

  20. Characterization and genome analysis of novel bacteriophages infecting the opportunistic human pathogens Klebsiella oxytoca and K. pneumoniae.

    PubMed

    Park, Eun-Ah; Kim, You-Tae; Cho, Jae-Hyun; Ryu, Sangryeol; Lee, Ju-Hoon

    2017-04-01

    Klebsiella is a genus of well-known opportunistic human pathogens that are associated with diabetes mellitus and chronic pulmonary obstruction; however, this pathogen is often resistant to multiple drugs. To control this pathogen, two Klebsiella-infecting phages, K. oxytoca phage PKO111 and K. pneumoniae phage PKP126, were isolated from a sewage sample. Analysis of their host range revealed that they infect K. pneumoniae and K. oxytoca, suggesting host specificity for members of the genus Klebsiella. Stability tests confirmed that the phages are stable under various temperature (4 to 60 °C) and pH (3 to 11) conditions. A challenge assay showed that PKO111 and PKP126 inhibit growth of their host strains by 2 log and 4 log, respectively. Complete genome sequencing of the phages revealed that their genome sizes are quite different (168,758 bp for PKO111 and 50,934 bp for PKP126). Their genome annotation results showed that they have no human virulence-related genes, an important safety consideration. In addition, no lysogen-formation gene cluster was detected in either phage genome, suggesting that they are both virulent phages in their bacterial hosts. Based on these results, PKO111 and PKP126 may be good candidates for development of biocontrol agents against members of the genus Klebsiella for therapeutic purposes. A comparative analysis of tail-associated gene clusters of PKO111 and PKP126 revealed relatively low homology, suggesting that they might differ in the way they recognize and infect their specific hosts.

  1. Combination of IMP-4 metallo-beta-lactamase production and porin deficiency causes carbapenem resistance in a Klebsiella oxytoca clinical isolate.

    PubMed

    Chen, Li-Rong; Zhou, Hong-Wei; Cai, Jia-Chang; Zhang, Rong; Chen, Gong-Xiang

    2009-10-01

    This study shows for the first time the mechanism of carbapenem resistance of a Klebsiella oxytoca clinical isolate ZC101 recovered from a Zhejiang University Hospital in Hangzhou, China. MIC values of imipenem, meropenem, and ertapenem for K. oxytoca ZC101 were 16, 16, and 128 microg/mL, respectively. Conjugation experiments demonstrated the transferability of a resistance determinant from K. oxytoca ZC101 to Escherichia coli EC600. Results from isoelectric focusing, polymerase chain reactions, and DNA sequencing confirmed that K. oxytoca ZC101 produced IMP-4 metallo-beta-lactamase (MBL) and CTX-M-14 extended-spectrum beta-lactamase, whereas E. coli transconjugant only produced the IMP-4. Amplification of integron revealed that bla(IMP-4) gene is located within a class I integron that was carried in a plasmid approximately 55 kb in size. Sodium dodecyl sulfate polyacrylamide gel electrophoresis profiling of outer membrane proteins of K. oxytoca ZC101 indicated lack of expression of the OmpK36 porin. DNA sequence analysis of ompK36 gene of K. oxytoca ZC101 showed the gene was disrupted by an insertion sequence IS5. In all, the results show that plasmid-mediated IMP-4 MBL production combined with the loss of OmpK36 porin caused the resistance in K. oxytoca ZC101 to carbapenems.

  2. Metabolic profiling of Klebsiella oxytoca: evaluation of methods for extraction of intracellular metabolites using UPLC/Q-TOF-MS.

    PubMed

    Park, Changhun; Yun, Seokhun; Lee, Sang Yup; Park, Kyungmoon; Lee, Jinwon

    2012-06-01

    The global pool of intracellular metabolites is a reflection of all the metabolic functions of an organism. In the absence of in situ methods capable of directly measuring metabolite pools, intracellular metabolite measurements need to be performed after an extraction procedure. In this study, we evaluated the optimization of technologies for generation of a global metabolomics profile for intracellular metabolites in Klebsiella oxytoca. Intracellular metabolites of K. oxytoca were extracted at the early stationary phase using six different common extraction procedures, including cold methanol, boiling ethanol, methanol/chloroform combinations, hot water, potassium hydroxide, and perchloric acid. The metabolites were subsequently collected for further analysis, and intracellular metabolite concentration profiles were generated using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. During analysis, the stability of metabolites extracted using cold methanol was clearly higher than that obtained by other extraction methods. For the majority of metabolites, extracts generated in this manner exhibited the greatest recovery, with high reproducibility. Therefore, the use of cold ethanol was the best extraction method for attaining a metabolic profile. However, in another parallel extraction method, perchloric acid may also be required to maximize the range of metabolites recovered, particularly to extract glucose 1-phosphate and NADPH.

  3. Fermentation of starch by Klebsiella oxytoca P2, containing plasmids with {alpha}-amylase and pullulanase genes

    SciTech Connect

    Santos, V.L. dos; Araujo, E.F.; Barros, E.G. de; Guimaraes, W.V.

    1999-12-20

    Klebsiella oxytoca P2(pC46), an ethanol-producing recombinant, has been evaluated in fermentation of maltose and starch. The maximum ethanol produced by P2(pC46) was 0.34 g ethanol/g maltose and 0.38, 0.40, or 0.36 g ethanol/g starch in fermentation of 1, 2, or 4% starch, representing 68, 71, and 64% the theoretical yield. The pC46 plasmid transformed to cells of K. oxytoca P2 reduced the ethanol production from maltose and starch. In fermentation of starch after its digestion at 60 C for 24 h, in two-step fermentation, the time for maximum ethanol production was reduced to 12--24 h and the theoretical yield was around 90%. The increase in starch concentration resulted in lower {alpha}-amylase activity but in higher pullulanase activity. The high activity and thermostability of the amylolytic enzymes from this transformant suggest that it has a potential for amylolytic enzymes source.

  4. Genotypes of Klebsiella oxytoca isolates from patients with nosocomial pneumonia are distinct from those of isolates from patients with antibiotic-associated hemorrhagic colitis.

    PubMed

    Herzog, Kathrin A T; Schneditz, Georg; Leitner, Eva; Feierl, Gebhard; Hoffmann, Karl Martin; Zollner-Schwetz, Ines; Krause, Robert; Gorkiewicz, Gregor; Zechner, Ellen L; Högenauer, Christoph

    2014-05-01

    Klebsiella oxytoca acts as a pathobiont in the dysbiotic human intestinal microbiota, causing antibiotic-associated hemorrhagic colitis (AAHC), but it also infects other organs, resulting in pneumonia and urinary tract and skin infections. The virulence of K. oxytoca is still poorly understood. The production of a specific cytotoxin has been linked to AAHC pathogenesis. To investigate the clonal relationships of K. oxytoca with regard to clinical origin and virulence attributes, we established a multilocus sequence typing (MLST) method and analyzed 74 clinical K. oxytoca isolates from asymptomatic carriers and patients with AAHC, respiratory infections, and other infections. The isolates were phenotypically characterized, typed, and compared phylogenetically based on the sequences of seven housekeeping genes. MLST analysis yielded 60 sequence types, 12 of which were represented by more than one isolate. The phylogenetic tree distinguished clusters of K. oxytoca isolates between patients with AAHC and those with respiratory infections. Toxin-positive and -negative strains were observed within one sequence type. Our findings indicate that AAHC isolates share a genetic background. Interestingly, K. oxytoca isolates from nosocomial pneumonia showed a different genetic clustering, suggesting that these strains do not originate from the intestines or that they are specialized for respiratory tract colonization. Our results further indicate a polyphyletic origin and possible horizontal transfer of the genes involved in K. oxytoca cytotoxin production. This work provides evidence that K. oxytoca isolates colonizing the two main clinically relevant habitats (lower gastrointestinal [GI] tract and respiratory tract) of the human host are genetically distinct. Applications of this MLST analysis should help clarify the sources of nosocomial infections.

  5. Production of allitol from D-psicose by a novel isolated strain of Klebsiella oxytoca G4A4.

    PubMed

    Han, Wenjia; Zhu, Yueming; Men, Yan; Yang, Jiangang; Liu, Can; Sun, Yuanxia

    2014-10-01

    A novel bacterium capable of producing allitol from D-psicose was isolated from soil and identified as Klebsiella oxytoca G4A4. An efficient method for the transformation of D-psicose to allitol was achieved through the resting cell reaction. Ribitol as an inducer is suitable for cell cultivation, and cells are most active in Tris-HCl buffer (pH 8.0) at 37 °C with a density of 40 (OD600 nm ). After the reaction, the final conversion rates of the washed cells were approximately 87, 83, and 55% at D-psicose concentrations of 0.25, 0.5, and 1%, respectively. The product from D-psicose was purified and determined to be allitol by high-performance liquid chromatography and nuclear magnetic resonance spectroscopy.

  6. Improved O2-tolerance in variants of a H2-evolving [NiFe]-hydrogenase from Klebsiella oxytoca HP1.

    PubMed

    Huang, Gang-Feng; Wu, Xiao-Bing; Bai, Li-Ping; Liu, Ke; Jiang, Li-Jing; Long, Min-Nan; Chen, Qing-Xi

    2015-04-02

    In this study, we investigated the mechanism of O2 tolerance of Klebsiella oxytoca HP1 H2-evolving hydrogenase 3 (KHyd3) by mutational analysis and three-dimensional structure modeling. Results revealed that certain surface amino acid residues of KHyd3 large subunit, in particular those at the outer entrance of the gas channel, have a visible effect on its oxygen tolerance. Additionally, solution pH, immobilization and O2 partial pressure also affect KHyd3 O2-tolerance to some extent. We propose that the extent of KHyd3 O2-tolerance is determined by a balance between the rate of O2 access to the active center through gas channels and the deoxidation rate of the oxidized active center. Based on our findings, two higher O2-tolerant KHyd3 mutations G300E and G300M were developed.

  7. Effects of Tween 80 on the removal, sorption and biodegradation of pyrene by Klebsiella oxytoca PYR-1.

    PubMed

    Zhang, Dong; Zhu, Lizhong

    2012-05-01

    The sorption and biodegradation of pyrene by Klebsiella oxytoca PYR-1 (PYR-1) in the presence of nonionic surfactant Tween 80 were investigated toward a better understanding that how surfactants can affect biodegradation of hydrophobic organic compounds. The results indicated that Tween 80 can promote the removal, sorption and biodegradation of pyrene depending on the surfactant concentration, of which the most significant promotion of biodegradation was achieved at critical micelle concentration of Tween 80 with an improvement of 22.4%. A highly positive correlation (P<0.0001) was observed between the biodegradation and sorption of pyrene with the presence of Tween 80. Biosorption experiments showed the same trends as biodegradation and further illustrated the improved biodegradation of pyrene was mainly due to surfactant-facilitated sorption. The regularly changes of cell surface hydrophobicity suggested formation of more hydrophobic surface caused by surfactant sorption lead to stimulation of pyrene sorption.

  8. Removal of nitrate from industrial wastewaters in a pilot plant by nitrate-tolerant Klebsiella oxytoca CECT 4460 and Arthrobacter globiformis CECT 4500

    SciTech Connect

    Pinar, G.; Ramos, J.L.; Oliva, J.M.; Sanchez-Barbero, L.; Calvo, V.

    1998-06-05

    Two strains, a gram-negative bacterium Klebsiella oxytoca CECT 4460 and a gram-positive, mycelium-forming bacterium Arthrobacter globiformis CECT 4500, tolerant to up to 1 M nitrate, were isolated from the grounds of a munitions factory. Under strict aerobic conditions and with appropriate C-sources, growth of these bacteria took place when the nitrate concentration in the medium was below 150 mM. Optimal growth conditions regarding the culture medium composition for the biological removal of nitrate were established in batch cultures. Then, the system was scaled up to a 40-L pilot plant and operated under continuous conditions in a factory with direct waste streams from dinitroethylene glycol production after appropriate dilution with nontreated groundwaters. The level of nitrate in the effluent was below 0.5% of the initial N-load. Nitrite and ammonium were undetectable and the level of the C-source in the effluent was below 50 mg per L. On the basis of these results, the authors conclude that the system worked on site satisfactorily.

  9. Enhanced reduction of Fe(III) oxides and methyl orange by Klebsiella oxytoca in presence of anthraquinone-2-disulfonate.

    PubMed

    Yu, Lei; Wang, Shi; Tang, Qing-Wen; Cao, Ming-Yue; Li, Jia; Yuan, Kun; Wang, Ping; Li, Wen-Wei

    2016-05-01

    Klebsiella oxytoca GS-4-08 is capable of azo dye reduction, but its quinone respiration and Fe(III) reduction abilities have not been reported so far. In this study, the abilities of this strain were reported in detail for the first time. As the biotic reduction of Fe(III) plays an important role in the biogeochemical cycles, two amorphous Fe(III) oxides were tested as the sole electron acceptor during the anaerobic respiration of strain GS-4-08. For the reduction of goethite and hematite, the biogenic Fe(II) concentrations reached 0.06 and 0.15 mM, respectively. Humic acid analog anthraquinone-2-disulfonate (AQS) was found to serve as an electron shuttle to increase the reduction of both methyl orange (MO) and amorphous Fe(III) oxides, and improve the dye tolerance of the strain. However, the formation of Fe(II) was not accelerated by biologically reduced AQS (B-AH2QS) because of the high bioavailability of soluble Fe(III). For the K. oxytoca strain, high soluble Fe(III) concentrations (above 1 mM) limit its growth and decolorization ability, while lower soluble Fe(III) concentrations produce an electron competition with MO initially, and then stimulate the decolorization after the electron couples of Fe(III)/Fe(II) are formed. With the ability to respire both soluble Fe(III) and insoluble Fe(III) oxides, this formerly known azo-reducer may be used as a promising model organism for the study of the interaction of these potentially competing processes in contaminated environments.

  10. XAS analysis of iron and palladium bonded to a polysaccharide produced anaerobically by a strain of Klebsiella oxytoca.

    PubMed

    Arčon, Iztok; Paganelli, Stefano; Piccolo, Oreste; Gallo, Michele; Vogel-Mikuš, Katarina; Baldi, Franco

    2015-09-01

    Klebsiella oxytoca BAS-10 ferments citrate to acetic acid and CO2, and secretes a specific exopolysaccharide (EPS), which is able to bind different metallic species. These biomaterials may be used for different biotechnological purposes, including applications as innovative green biogenerated catalysts. In production of biogenerated Pd species, the Fe(III) as ferric citrate is added to anaerobic culture of K. oxytoca BAS-10, in the presence of palladium species, to increase the EPS secretion and improve Pd-EPS yield. In this process, bi-metallic (FePd-EPS) biomaterials were produced for the first time. The morphology of bi-metallic EPS, and the chemical state of the two metals in the FePd-EPS, are investigated by transmission electron microscopy, Fourier transform infra-red spectroscopy, micro-X-ray fluorescence, and X-ray absorption spectroscopy methods (XANES and EXAFS), and compared with mono-metallic Pd-EPS and Fe-EPS complexes. Iron in FePd-EPS is in the mineralized form of iron oxides/hydroxides, predominantly in the form of Fe(3+), with a small amount of Fe(2+) in the structure, most probably a mixture of different nano-crystalline iron oxides and hydroxides, as in mono-metallic Fe-EPS. Palladium is found as Pd(0) in the form of metallic nanoparticles with face-centred cubic structure in both bi-metallic (FePd-EPS) and mono-metallic (Pd-EPS) species. In bi-metallic species, Pd and Fe nanoparticles agglomerate in larger clusters, but they remain spatially separated. The catalytic ability of bi-metallic species (FePd-EPS) in a hydrodechlorination reaction is improved in comparison with mono-metallic Pd-EPS.

  11. Cloning and construction of recombinant palI gene from Klebsiella oxytoca on pET-32b into E. coli BL21 (DE3) pLysS for production of isomaltulose, a new generation of sugar

    SciTech Connect

    Moeis, Maelita R. Berlian, Liska Suhandono, Sony Prima, Alex Komalawati, Eli Kristianti, Tati

    2014-03-24

    Klebsiella oxytoca produces sucrose isomerase which catalyses the conversion of sucrose to isomaltulose, a new generation of sugar. From the previous study, palI gene from Klebsiella oxytoca was succesfully isolated from sapodilla fruit (Manilkara zapota). The full-length palI gene sequence of Klebsiella oxytoca was cloned in E. coli DH5α. The deduced amino acid sequence shows 498 residues which includes conserved motif for sucrose isomerisation {sup 325}RLDRD{sup 329} and 97% identical to palI gene from Klebsiella sp. LX3 (GenBank:AAK82938.1). This fragment was succesfullly ligated into the expression vector pET-32b using overlap-extension PCR and cloned in Escherichia coli BL21 (DE3) pLysS. DNA sequencing result shows that palI gene of Klebsiella oxytoca was inserted in-frame in pET-32b. This is the first report on cloning of palI gene from Klebsiella oxytoca.

  12. Cloning and construction of recombinant palI gene from Klebsiella oxytoca on pET-32b into E. coli BL21 (DE3) pLysS for production of isomaltulose, a new generation of sugar

    NASA Astrophysics Data System (ADS)

    Moeis, Maelita R.; Berlian, Liska; Suhandono, Sony; Prima, Alex; Komalawati, Eli; Kristianti, Tati

    2014-03-01

    Klebsiella oxytoca produces sucrose isomerase which catalyses the conversion of sucrose to isomaltulose, a new generation of sugar. From the previous study, palI gene from Klebsiella oxytoca was succesfully isolated from sapodilla fruit (Manilkara zapota). The full-length palI gene sequence of Klebsiella oxytoca was cloned in E. coli DH5α. The deduced amino acid sequence shows 498 residues which includes conserved motif for sucrose isomerisation 325RLDRD329 and 97% identical to palI gene from Klebsiella sp. LX3 (GenBank:AAK82938.1). This fragment was succesfullly ligated into the expression vector pET-32b using overlap-extension PCR and cloned in Escherichia coli BL21 (DE3) pLysS. DNA sequencing result shows that palI gene of Klebsiella oxytoca was inserted in-frame in pET-32b. This is the first report on cloning of palI gene from Klebsiella oxytoca.

  13. Antimicrobial activity of essential oils of cultivated oregano (Origanum vulgare), sage (Salvia officinalis), and thyme (Thymus vulgaris) against clinical isolates of Escherichia coli, Klebsiella oxytoca, and Klebsiella pneumoniae

    PubMed Central

    Fournomiti, Maria; Kimbaris, Athanasios; Mantzourani, Ioanna; Plessas, Stavros; Theodoridou, Irene; Papaemmanouil, Virginia; Kapsiotis, Ioannis; Panopoulou, Maria; Stavropoulou, Elisavet; Bezirtzoglou, Eugenia E.; Alexopoulos, Athanasios

    2015-01-01

    Background Oregano (Origanum vulgare), sage (Salvia officinalis), and thyme (Thymus vulgaris) are aromatic plants with ornamental, culinary, and phytotherapeutic use all over the world. In Europe, they are traditionally used in the southern countries, particularly in the Mediterranean region. The antimicrobial activities of the essential oils (EOs) derived from those plants have captured the attention of scientists as they could be used as alternatives to the increasing resistance of traditional antibiotics against pathogen infections. Therefore, significant interest in the cultivation of various aromatic and medicinal plants is recorded during the last years. However, to gain a proper and marketable chemotype various factors during the cultivation should be considered as the geographical morphology, climatic, and farming conditions. In this frame, we have studied the antimicrobial efficiency of the EOs from oregano, sage, and thyme cultivated under different conditions in a region of NE Greece in comparison to the data available in literature. Methods Plants were purchased from a certified supplier, planted, and cultivated in an experimental field under different conditions and harvested after 9 months. EOs were extracted by using a Clevenger apparatus and tested for their antibacterial properties (Minimum inhibitory concentration – MIC) against clinical isolates of multidrug resistant Escherichia coli (n=27), Klebsiella oxytoca (n=7), and Klebsiella pneumoniae (n=16) strains by using the broth microdilution assay. Results Our results showed that the most sensitive organism was K. oxytoca with a mean value of MIC of 0.9 µg/mL for oregano EOs and 8.1 µg/mL for thyme. The second most sensitive strain was K. pneumoniae with mean MIC values of 9.5 µg/mL for thyme and 73.5 µg/mL for oregano EOs. E. coli strains were among the most resistant to EOs antimicrobial action as the observed MICs were 24.8–28.6 µg/mL for thyme and above 125 µg/mL for thyme and sage

  14. Dissemination of clinical isolates of Klebsiella oxytoca harboring CMY-31, VIM-1, and a New OXY-2-type variant in the community.

    PubMed

    Tsakris, Athanassios; Poulou, Aggeliki; Markou, Fani; Pitiriga, Vassiliki; Piperaki, Evangelia-Theophano; Kristo, Ioulia; Pournaras, Spyros

    2011-07-01

    The aim of the present study was to investigate the epidemiological link of multidrug-resistant Klebsiella oxytoca isolates causing community-onset infections among patients attending our outpatient department and to investigate the underlying resistance mechanisms. The isolates were tested by agar dilution MICs, phenotypic carbapenemase testing, enterobacterial repetitive intergenic consensus-PCR, and pulsed-field gel electrophoresis (PFGE). PCR assays and nucleotide sequencing were employed for the identification of bla gene types and the mapping of the integron-containing metallo-β-lactamase (MBL) gene. During the study period (January 2005 to April 2007), nine broad-spectrum cephalosporin-resistant K. oxytoca clinical isolates were prospectively collected from separate outpatients with urinary tract infections. In all cases, the patients had been hospitalized or exposed to health care facilities during the preceding year. Molecular typing revealed that all isolates belonged to the same K. oxytoca clonal type, which contained five PFGE subtypes. A novel chromosomal OXY-2 β-lactamase type variant (OXY-2-9) was detected in all isolates, but no mutations in the promoter region justifying bla(OXY) gene overproduction were detected. In addition, all isolates harbored the plasmidic CMY-31 (LAT-4) AmpC cephalosporinase, while three of them harbored VIM-1 MBL in a class 1 integron structure. This is the first study to present the dissemination in the community of multidrug-resistant K. oxytoca isolates causing extrahospital infections.

  15. Dissemination of Clinical Isolates of Klebsiella oxytoca Harboring CMY-31, VIM-1, and a New OXY-2-Type Variant in the Community ▿

    PubMed Central

    Tsakris, Athanassios; Poulou, Aggeliki; Markou, Fani; Pitiriga, Vassiliki; Piperaki, Evangelia-Theophano; Kristo, Ioulia; Pournaras, Spyros

    2011-01-01

    The aim of the present study was to investigate the epidemiological link of multidrug-resistant Klebsiella oxytoca isolates causing community-onset infections among patients attending our outpatient department and to investigate the underlying resistance mechanisms. The isolates were tested by agar dilution MICs, phenotypic carbapenemase testing, enterobacterial repetitive intergenic consensus-PCR, and pulsed-field gel electrophoresis (PFGE). PCR assays and nucleotide sequencing were employed for the identification of bla gene types and the mapping of the integron-containing metallo-β-lactamase (MBL) gene. During the study period (January 2005 to April 2007), nine broad-spectrum cephalosporin-resistant K. oxytoca clinical isolates were prospectively collected from separate outpatients with urinary tract infections. In all cases, the patients had been hospitalized or exposed to health care facilities during the preceding year. Molecular typing revealed that all isolates belonged to the same K. oxytoca clonal type, which contained five PFGE subtypes. A novel chromosomal OXY-2 β-lactamase type variant (OXY-2-9) was detected in all isolates, but no mutations in the promoter region justifying blaOXY gene overproduction were detected. In addition, all isolates harbored the plasmidic CMY-31 (LAT-4) AmpC cephalosporinase, while three of them harbored VIM-1 MBL in a class 1 integron structure. This is the first study to present the dissemination in the community of multidrug-resistant K. oxytoca isolates causing extrahospital infections. PMID:21555768

  16. A novel Fe(III) dependent bioflocculant from Klebsiella oxytoca GS-4-08: culture conditions optimization and flocculation mechanism.

    PubMed

    Yu, Lei; Tang, Qing-Wen; Zhang, Yu-Jia; Chen, Rong-Ping; Liu, Xin; Qiao, Wei-Chuan; Li, Wen-Wei; Ruan, Hong-Hua; Song, Xin

    2016-10-07

    In this work, the effect of cultivation factors on the flocculation efficiency (FE) of bioflocculant P-GS408 from Klebsiella oxytoca was optimized by the response surface methodology. The most significant factor, i.e. culture time, was determined by gray relational analysis. A total of 240 mg of purified P-GS408 was prepared from 1 liter of culture solution under the optimal conditions. GC-MS analysis results indicated that the polysaccharide of P-GS408 mainly contains Rhamnose and Galactose, and the existence of abundant hydroxyl, carboxyl and amino groups was evidenced by FTIR and XPS analyses. With the aid of Fe(3+), the FE of kaolin solution by P-GS408 could achieve 99.48% in ten minutes. Functional groups of polysaccharide were involved in the first adsorption step and the zeta potential of kaolin solution changed from -39.0 mV to 43.4 mV in the presence of Fe(3+) and P-GS408. Three-dimensional excitation-emission (EEM) fluorescence spectra demonstrates that the trivalent Fe(3+) and Al(3+) can bind efficiently with P-GS408, while those univalent and divalent cations cannot. With the help of SEM images, FTIR, zeta potential and EEM spectra, we proposed the P-GS408 flocculation mechanism, which consists of coordination bond combination, charge neutrality, adsorption and bridging, and net catching.

  17. A novel Fe(III) dependent bioflocculant from Klebsiella oxytoca GS-4-08: culture conditions optimization and flocculation mechanism

    PubMed Central

    Yu, Lei; Tang, Qing-wen; Zhang, Yu-jia; Chen, Rong-ping; Liu, Xin; Qiao, Wei-chuan; Li, Wen-wei; Ruan, Hong-hua; Song, Xin

    2016-01-01

    In this work, the effect of cultivation factors on the flocculation efficiency (FE) of bioflocculant P-GS408 from Klebsiella oxytoca was optimized by the response surface methodology. The most significant factor, i.e. culture time, was determined by gray relational analysis. A total of 240 mg of purified P-GS408 was prepared from 1 liter of culture solution under the optimal conditions. GC-MS analysis results indicated that the polysaccharide of P-GS408 mainly contains Rhamnose and Galactose, and the existence of abundant hydroxyl, carboxyl and amino groups was evidenced by FTIR and XPS analyses. With the aid of Fe3+, the FE of kaolin solution by P-GS408 could achieve 99.48% in ten minutes. Functional groups of polysaccharide were involved in the first adsorption step and the zeta potential of kaolin solution changed from −39.0 mV to 43.4 mV in the presence of Fe3+ and P-GS408. Three-dimensional excitation-emission (EEM) fluorescence spectra demonstrates that the trivalent Fe3+ and Al3+ can bind efficiently with P-GS408, while those univalent and divalent cations cannot. With the help of SEM images, FTIR, zeta potential and EEM spectra, we proposed the P-GS408 flocculation mechanism, which consists of coordination bond combination, charge neutrality, adsorption and bridging, and net catching. PMID:27713559

  18. Isolation and characterization of Klebsiella oxytoca strain degrading crude oil from a Tunisian off-shore oil field.

    PubMed

    Chamkha, Mohamed; Trabelsi, Yosra; Mnif, Sami; Sayadi, Sami

    2011-12-01

    A facultatively anaerobic, Gram-negative, mesophilic, moderately halotolerant, non-motile, and non-sporulated bacterium, designated strain BSC5 was isolated from an off-shore "Sercina" oil field, located near the Kerkennah island, Tunisia. Yeast extract was not required for growth. Phenotypic characteristics and phylogenetic analysis of the 16S rRNA gene sequence of strain BSC5 revealed that it was related to members of the genus Klebsiella, being most closely related to the type strain of K. oxytoca (99% sequence similarity). Strain BSC5 was capable of using aerobically the crude oil as substrate growth. The growth of strain BSC5 on crude oil was followed by measuring the OD(600 nm) and by enumeration of viable cells at different culture's time. GC-MS analysis showed that strain BSC5 was capable of degrading a wide range of aliphatic hydrocarbons from C(13) to C(30) . The biodegradation rate for n -alkanes reached 44% and 75%, after 20 and 45 days of incubation, respectively. Addition of the synthetic surfactant, Tween 80, accelerated the crude oil degradation. The biodegradation rate for n -alkanes reached 61% and 98%, after 20 and 45 days of incubation, respectively. Moreover, three aromatic compounds, p -hydroxybenzoate, protocatechuate and gentisate, were metabolized completely by strain BSC5 after 24 h, under aerobic conditions.

  19. Metabolic engineering of Klebsiella oxytoca M5a1 to produce optically pure D-lactate in mineral salts medium.

    PubMed

    Sangproo, Maytawadee; Polyiam, Pattharasedthi; Jantama, Sirima Suvarnakuta; Kanchanatawee, Sunthorn; Jantama, Kaemwich

    2012-09-01

    Klebsiella oxytoca strains were constructed to produce optical pure d-lactate by pH-controlled batch fermentation in mineral salts medium. The alcohol dehydrogenase gene, adhE, and the phospho-transacetylase/acetate kinase A genes, pta-ackA, were deleted from the wild type. KMS002 (ΔadhE) and KMS004 (ΔadhE Δpta-ackA) exhibited d-lactate production as a primary pathway for the regeneration of NAD(+). Both strains produced 11-13 g/L of d-lactate in medium containing 2% (w/v) glucose with yields of 0.64-0.71 g/g glucose used. In sugarcane molasses, KMS002 and KMS004 produced 22-24 g/L of d-lactate with yields of 0.80-0.87 g/g total sugars utilized. Both strains also utilized maltodextrin derived from cassava starch and produced d-lactate at a concentration of 33-34 g/L with yields of 0.91-0.92 g/g maltodextrin utilized. These d-lactate yields are higher than those reported for engineered E. coli strains.

  20. Influences and mechanisms of surfactants on pyrene biodegradation based on interactions of surfactant with a Klebsiella oxytoca strain.

    PubMed

    Zhang, Dong; Zhu, Lizhong; Li, Feng

    2013-08-01

    Surfactant-enhanced bioremediation has been proposed as a promising technology for the treatment of organic polluted soils; however its application has been hindered by the controversial influences and mechanisms of surfactants on the biodegradation of hydrophobic organic compounds. To address this problem, effects of five surfactants on the sorption and biodegradation of pyrene by Klebsiella oxytoca PYR-1, as well as their interactions with bacterial cell surface and membrane lipids were investigated. We found that surfactants enhanced or inhibited pyrene biodegradation depending on their effects on the sorption of pyrene onto bacterial cell, which occurred mainly through modifying cell surface hydrophobicity (such as Tween series surfactants) or disrupting bacterial membrane (such as Triton X-100), respectively. A relatively high positive correlation (P<0.0001) was observed between biodegradation promotion (Bs/B0) and enhancement of sorption coefficients (Kd,s(∗)/Kd,0(∗)) for pyrene in the presence of surfactant, indicating that surfactant-induced sorption played the dominant role during pyrene biodegradation.

  1. Polysaccharide-based silver nanoparticles synthesized by Klebsiella oxytoca DSM 29614 cause DNA fragmentation in E. coli cells.

    PubMed

    Baldi, Franco; Daniele, Salvatore; Gallo, Michele; Paganelli, Stefano; Battistel, Dario; Piccolo, Oreste; Faleri, Claudia; Puglia, Anna Maria; Gallo, Giuseppe

    2016-04-01

    Silver nanoparticles (AgNPs), embedded into a specific exopolysaccharide (EPS), were produced by Klebsiella oxytoca DSM 29614 by adding AgNO3 to the cultures during exponential growth phase. In particular, under aerobic or anaerobic conditions, two types of silver nanoparticles, named AgNPs-EPS(aer) and the AgNPs-EPS(anaer), were produced respectively. The effects on bacterial cells was demonstrated by using Escherichia coli K12 and Kocuria rhizophila ATCC 9341 (ex Micrococcus luteus) as Gram-negative and Gram-positive tester strains, respectively. The best antimicrobial activity was observed for AgNPs-EPS(aer), in terms of minimum inhibitory concentrations and minimum bactericidal concentrations. Observations by transmission electron microscopy showed that the cell morphology of both tester strains changed during the exposition to AgNPs-EPS(aer). In particular, an electron-dense wrapped filament was observed in E. coli cytoplasm after 3 h of AgNPs-EPS(aer) exposition, apparently due to silver accumulation in DNA, and both E. coli and K. rhizophila cells were lysed after 18 h of exposure to AgNPs-EPS(aer). The DNA breakage in E. coli cells was confirmed by the comparison of 3-D fluorescence spectra fingerprints of DNA. Finally the accumulation of silver on DNA of E. coli was confirmed directly by a significant Ag(+) release from DNA, using the scanning electrochemical microscopy and the voltammetric determinations.

  2. Rapid characterisation of Klebsiella oxytoca isolates from contaminated liquid hand soap using mass spectrometry, FTIR and Raman spectroscopy.

    PubMed

    Dieckmann, Ralf; Hammerl, Jens Andre; Hahmann, Hartmut; Wicke, Amal; Kleta, Sylvia; Dabrowski, Piotr Wojciech; Nitsche, Andreas; Stämmler, Maren; Al Dahouk, Sascha; Lasch, Peter

    2016-06-23

    Microbiological monitoring of consumer products and the efficiency of early warning systems and outbreak investigations depend on the rapid identification and strain characterisation of pathogens posing risks to the health and safety of consumers. This study evaluates the potential of three rapid analytical techniques for identification and subtyping of bacterial isolates obtained from a liquid hand soap product, which has been recalled and reported through the EU RAPEX system due to its severe bacterial contamination. Ten isolates recovered from two bottles of the product were identified as Klebsiella oxytoca and subtyped using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI TOF MS), near-infrared Fourier transform (NIR FT) Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Comparison of the classification results obtained by these phenotype-based techniques with outcomes of the DNA-based methods pulsed-field gel electrophoresis (PFGE), multi-locus sequence typing (MLST) and single nucleotide polymorphism (SNP) analysis of whole-genome sequencing (WGS) data revealed a high level of concordance. In conclusion, a set of analytical techniques might be useful for rapid, reliable and cost-effective microbial typing to ensure safe consumer products and allow source tracking.

  3. Enhanced 2,3-Butanediol Production by Optimizing Fermentation Conditions and Engineering Klebsiella oxytoca M1 through Overexpression of Acetoin Reductase.

    PubMed

    Cho, Sukhyeong; Kim, Taeyeon; Woo, Han Min; Lee, Jinwon; Kim, Yunje; Um, Youngsoon

    2015-01-01

    Microbial production of 2,3-butanediol (2,3-BDO) has been attracting increasing interest because of its high value and various industrial applications. In this study, high production of 2,3-BDO using a previously isolated bacterium Klebsiella oxytoca M1 was carried out by optimizing fermentation conditions and overexpressing acetoin reductase (AR). Supplying complex nitrogen sources and using NaOH as a neutralizing agent were found to enhance specific production and yield of 2,3-BDO. In fed-batch fermentations, 2,3-BDO production increased with the agitation speed (109.6 g/L at 300 rpm vs. 118.5 g/L at 400 rpm) along with significantly reduced formation of by-product, but the yield at 400 rpm was lower than that at 300 rpm (0.40 g/g vs. 0.34 g/g) due to acetoin accumulation at 400 rpm. Because AR catalyzing both acetoin reduction and 2,3-BDO oxidation in K. oxytoca M1 revealed more than 8-fold higher reduction activity than oxidation activity, the engineered K. oxytoca M1 overexpressing the budC encoding AR was used in fed-batch fermentation. Finally, acetoin accumulation was significantly reduced by 43% and enhancement of 2,3-BDO concentration (142.5 g/L), yield (0.42 g/g) and productivity (1.47 g/L/h) was achieved compared to performance with the parent strain. This is by far the highest titer of 2,3-BDO achieved by K. oxytoca strains. This notable result could be obtained by finding favorable fermentation conditions for 2,3-BDO production as well as by utilizing the distinct characteristic of AR in K. oxytoca M1 revealing the nature of reductase.

  4. Biofilm growth of individual and dual strains of Klebsiella oxytoca from the dairy industry on ultrafiltration membranes.

    PubMed

    Tang, Xuemei; Flint, Steve H; Bennett, Rod J; Brooks, John D; Morton, R Hugh

    2009-12-01

    Formation of biofilms in dairy membrane plants causes membrane pore blocking, product contamination and subsequent economic loss. To investigate the biofilm growth, two Klebsiella oxytoca strains, K. B006 and TR002, previously isolated from New Zealand dairy membrane plants, were grown both individually and combined on three types of ultrafiltration (UF) membranes in different concentrations of whey medium in biofilm reactors (CBR 90, BioSurface Technologies, Bozeman, USA). Biofilms of both the individual and combined strains grew on the membrane surfaces to levels of 4.9-7.99 log colony-forming units (CFU) cm(-2) measured by standard plate counting after removing the cells by sonication. More biofilm grew on used polyethersulfone (PES) membranes than on new PES and polyvinylidene fluoride (PVDF) membranes. Both strains formed good biofilms, although K. B006 formed a denser biofilm than TR002. This corresponded to our previous study on the attachment of these organisms, where K. B006 attached in greater numbers than K. TR002. The dual strains produced a higher biofilm density than single strains on the new membranes. Biofilm density tended to increase with increased whey concentration. The saturated biofilm was approximately 10(8) CFU cm(-2). PES membranes appeared to support biofilm growth less readily than did PVDF membranes and therefore may be the preferred material for UF membranes to reduce problems with microbial colonisation. Used membranes were more readily colonised with biofilm than were new membranes. Therefore, selecting a membrane type and monitoring membrane age will help manage biofilm development during UF.

  5. Colistin- and carbapenem-resistant Klebsiella oxytoca harboring blaVIM-2 and an insertion in the mgrB gene isolated from blood culture.

    PubMed

    Simon, Michaela; Melzl, Holger; Hiergeist, Andreas; Richert, Katharina; Falgenhauer, Linda; Pfeifer, Yvonne; Gerlach, Roman G; Fuchs, Kornelius; Reischl, Udo; Gessner, André; Jantsch, Jonathan

    2017-02-01

    A carbapenemase-producing colistin-resistant Klebsiella oxytoca isolate was recovered from a blood culture of a female patient without previous report of risk factors to obtain multidrug-resistant Gram-negative bacilli. A combination of biochemical and molecular methods was used to identify the resistance mechanism of this isolate. Carbapenemase production was mediated by Verona integron-encoded metallo-β-lactamase (VIM)-2. Colistin resistance was not due to plasmid- borne mcr-1 gene, but we found an integration of IS5-like sequence in the mgrB gene of K. oxytoca. This gene is known to be an important regulator of the PhoPQ two-component system, and the disruption of this gene is most likely the cause of lipid A modification resulting in colistin resistance of our isolate. To the best of our knowledge this constitutes the first report of a carbapenemase-producing K. oxytoca with colistin resistance, a case that demonstrates the limited treatment options for infections with multidrug-resistant organisms.

  6. Evaluation of the Clinical and Laboratory Standards Institute phenotypic confirmatory test to detect the presence of extended-spectrum β-lactamases from 4005 Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae and Proteus mirabilis isolates.

    PubMed

    Morrissey, Ian; Bouchillon, Samuel K; Hackel, Meredith; Biedenbach, Douglas J; Hawser, Stephen; Hoban, Daryl; Badal, Robert E

    2014-04-01

    A subset of Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae and Proteus mirabilis isolates collected for the Study for Monitoring Antimicrobial Resistance Trends that were positive for the Clinical and Laboratory Standards Institute (CLSI) extended-spectrum β-lactamase (ESBL) phenotypic confirmatory test (n = 3245) or had an ertapenem MIC of ≥0.5 µg ml(-1) (n = 293), or both (n = 467), were analysed for ESBL genes. Most ESBL phenotype E. coli or K. pneumoniae possessed an ESBL gene (95.8 and 88.4 %, respectively), and this was 93.1 % if carbapenem-non-susceptible K. pneumoniae were removed. This rate was lower for P. mirabilis (73.4 %) and K. oxytoca (62.5 %). Virtually all ESBL-positive isolates (99.5 %) were cefotaxime non-susceptible [CLSI or European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints)]. Fewer isolates (82 %) were ceftazidime non-susceptible (CLSI breakpoints). In addition, 21.1 % of E. coli, 25 % of K. oxytoca and 78.7 % of P. mirabilis isolates were ceftazidime susceptible but ESBL positive. This suggests that CLSI breakpoints for ceftazidime are too high to detect ESBLs. The lower EUCAST breakpoints detected ESBLs in E. coli and K. oxytoca better, but 59.6 % of ESBL-positive isolates of P. mirabilis were ceftazidime susceptible. For isolates with ertapenem MICs ≥0.5 µg ml(-1), more accurate ESBL phenotype analysis was observed for E. coli and K. pneumoniae (sensitivity >95 % for both, specificity 94.4 and 54.1 %, respectively). If carbapenemase-positive K. pneumoniae were excluded, the specificity increased to 78 %. The positive predictive values for the ESBL phenotypic test with E. coli and K. pneumoniae were 97.6 and 81.8 %, respectively, and negative predictive values were 75.9 and 95.2 %, respectively. We therefore suggest that it would be prudent to confirm phenotypic ESBL-positive P. mirabilis, K. pneumoniae and K. oxytoca with molecular analysis.

  7. [Profiles of the utilization of 20 amino acids as the only source of nitrogen and carbon in bacteria of the genera Klebsiella, Enterobacter, Serratia, Escherichia].

    PubMed

    Sivolodskiĭ, E P

    2005-01-01

    The profiles of the utilization of 20 protein amino acids in 118 Klebsiella pneumoniae sub- sp. pneumoniae, K. oxytoca, K. planticola, K. mobilis, Enterobacter cloacae, Serratia marscescens, S. liquefaciens, Escherichia coli strains isolated from clinical material were studied. The utilization of amino acids was determined on minimal saline agar containing amino acid as the only source of nitrogen and carbon; the results were evaluated after 72-hour incubation at 37 degrees C. 17 profiles of amino-acid utilization were thus determined, most of them genus-specific in enterobacteria: Klebsiella (profiles No. 1--6, 9, 10), Enterobacter (No. 11--13), Serratia (No. 14--16), Escherichia (No. 17). The full coincidence of amino-acid utilization profiles in bacteria of K. mobilis (No. 1, 6) and K. pneumoniae subsp. pneumoniae with out of such profiles in bacteria of the genera Enterobacter, Serratia, Escherichia was established, which confirmed that K. mobilis (formerly Enterobacter aerogenes) belonged to the genus Klebsiella.

  8. Effect of pH on the metabolic flux of Klebsiella oxytoca producing 2,3-butanediol in continuous cultures at different dilution rates.

    PubMed

    Park, Changhun; Lu, Mingshou; Yun, Seokhun; Park, Kyungmoon; Lee, Jinwon

    2013-06-01

    The efficiency of the bioconversion process and the achievable end-product concentration decides the economic feasibility of microbial 2,3-butanediol (2,3-BDO) production. In 2,3-BDO production, optimization of culture condition is required for cell growth and metabolism. Also, the pH is an important factor that influences microbial performance. For different microorganisms and substrates, it has been shown that the distribution of the metabolites in 2,3-BDO fermentation is greatly affected by pH, and the optimum pH for 2,3-BDO production seems dependently linked to the particular strain and the substrate employed. Quantification analysis of intracellular metabolites and metabolic flux analysis (MFA) were used to investigate the effect of pH on the Klebsiella oxytoca producing 2,3-BDO and other organic acids. The main objectives of MFA are the estimation of intracellular metabolic fluxes and the identification of rate-limiting step and the key enzymes. This study was conducted under continuous aerobic conditions at different dilution rates (0.1, 0.2, and 0.3 h(-1)) and different pH values (pH 5.5 and 7.0) for the steady-state experimental data. In order to obtain the flux distribution, the extracellular specific rates were calculated from the experimental data using the metabolic network model of K. oxytoca. Intracellular metabolite concentration profiles were generated using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry.

  9. Influence of blocking of 2,3-butanediol pathway on glycerol metabolism for 1,3-propanediol production by Klebsiella oxytoca.

    PubMed

    Zhang, Gang; Yang, Guang; Wang, Xu; Guo, Qingjuan; Li, Ying; Li, Jilun

    2012-09-01

    Glycerol metabolism is a typical biological oxidoreductive reaction. 1,3-Propanediol (1,3-PD) is the final product of the reductive branch, while acetate, succinate, lactate, 2,3-butanediol (2,3-BD), and ethanol were produced in the oxidative branch. 2,3-BD, which has similar properties of high boiling point and water solubility with 1,3-PD, not only contests the carbon flow and NADH with 1,3-PD but also serves as an obstacle for obtaining high purity 1,3-PD in downstream processes. In this study, a 2,3-BD pathway-deficient mutant of Klebsiella oxytoca ZG36 was constructed by knocking out the budA gene of the wild-type strain M5al. The results of fed-batch fermentation by ZG36 indicated that the glycerol flux and the distribution of metabolites were altered in the K. oxytoca when the 2,3-BD pathway was blocked. No 2,3-BD was produced, and the activity of α-acetolactate decarboxylase (α-ALDC) can not be detected in the fermentation processes. The indexes of the 1,3-PD titer, the conversion from glycerol to 1,3-PD, and the productivity per cell dry weight (CDW) increased by 42%, 62%, and 46%, respectively, compared with the M5al, and the yield of the byproducts also increased obviously. The assay of the enzyme activities in the oxidative branch and the reductive branch of the glycerol metabolism, as well as the intracellular redox state, exposited the results logically.

  10. Molecular cloning of kman coding for mannanase from Klebsiella oxytoca KUB-CW2-3 and its hybrid mannanase characters.

    PubMed

    Pongsapipatana, Nawapan; Damrongteerapap, Piyanat; Chantorn, Sudathip; Sintuprapa, Wilawan; Keawsompong, Suttipun; Nitisinprasert, Sunee

    2016-07-01

    Gene encoding for β-mannanase (E.C 3.2.1.78) from Klebsiella oxytoca KUB-CW2-3 was cloned and expressed by an E. coli system resulting in 400 times higher mannanase activities than the wild type. A 3314bp DNA fragment obtained revealed an open reading frame of 1164bp, namely kman-2, which encoded for 387 amino acids with an estimated molecular weight of 43.2kDa. It belonged to the glycosyl hydrolase family 26 (GH26) exhibited low similarity of 50-71% to β-mannanase produced by other microbial sources. Interestingly, the enzyme had a broad range of substrate specificity of homopolymer of ivory nut mannan (6%), carboxymethyl cellulose (30.6%) and avicel (5%), and heteropolymer of konjac glucomannan (100%), locust bean gum (92.6%) and copra meal (non-defatted 5.3% and defatted 7%) which would be necessary for in vivo feed digestion. The optimum temperature and pH were 30-50°C and 4-6, respectively. The enzyme was still highly active over a low temperature range of 10-40°C and over a wide pH range of 4-10. The hydrolysates of konjac glucomannan (H-KGM), locust bean gum (H-LBG) and defatted copra meal (H-DCM) composed of compounds which were different in their molecular weight range from mannobiose to mannohexaose and unknown oligosaccharides indicating the endo action of mannanase. Both H-DCM and H-LBG enhanced the growth of lactic acid bacteria and some pathogens except Escherichia coli E010 with a specific growth rate of 0.36-0.83h(-1). H-LBG was more specific to 3 species of Weissella confusa JCM 1093, Lactobacillus reuteri KUB-AC5, Lb salivarius KL-D4 and E. coli E010 while both H-KGM and H-DCM were to Lb. reuteri KUB-AC5 and Lb. johnsonii KUNN19-2. Based on the nucleotide sequence of kman-2 containing two open reading frames of 1 and 2at 5' end of the +1 and +43, respectively, removal of the first open reading frame provided the recombinant clone E. coli KMAN-3 resulting in the mature protein of mannanase composing of 345 amino acid residues confirmed by 3D

  11. Detection of an IncA/C plasmid encoding VIM-4 and CMY-4 β-lactamases in Klebsiella oxytoca and Citrobacter koseri from an inpatient in a cardiac rehabilitation unit.

    PubMed

    Caltagirone, Mariasofia; Bitar, Ibrahim; Piazza, Aurora; Spalla, Melissa; Nucleo, Elisabetta; Navarra, Antonella; Migliavacca, Roberta

    2015-07-01

    A 62-year-old patient was transferred to the cardiac rehabilitation unit of the I.R.C.C.S. Fondazione S. Maugeri after undergoing a heart transplantation at the Acute Care Hospital I.R.C.C.S. S. Matteo of Pavia. On 1 August 2013 and during hospitalization in the rehabilitation unit, Klebsiella oxytoca and Citrobacter koseri clinical isolates were simultaneously recovered from the patient's preputial swab. Both the K. oxytoca and C. koseri strains were carbapenem- resistant by MicroScan System (Beckman Coulter). Carbapenem-resistant K. pneumoniae had previously been reported in the same rehabilitation facility. The aim of the study was to identify the carbapenem resistance mechanisms among the enterobacterial species recovered. Phenotypic screening tests useful to detect the β-lactamases/carbapenemases were performed. Carbapenem MICs were obtained by Etest. AmpC and MBL encoding genes were identified by PCR and sequencing. Conjugation assays and plasmid characterization were performed. Both of the K. oxytoca and C. koseri isolates were multi drug resistant, showing resistance to amoxicillin-clavulanic acid, three generation cephalosporins, ertapenem (K. oxytoca MIC, >32 mg/L; C. koseri MIC, 4 mg/L), imipenem (K. oxytoca MIC, 4 mg/L; C. koseri MIC, 12 mg/L), thrimethoprim sulphamethoxazole and gentamicin. Susceptibility was retained to fluoroquinolones, colistin and tigecycline. Molecular characterization confirmed the co-presence of blaCMY-4 and blaVIM-4 determinants in a 150 Kb transferable plasmid of IncA/C group. This case is the first detection in Italy of the K. oxytoca and C. koseri clinical isolates co-producing the CMY-4 and VIM-4 enzymes.

  12. Development of an industrial medium for economical 2,3-butanediol production through co-fermentation of glucose and xylose by Klebsiella oxytoca.

    PubMed

    Ji, Xiao-Jun; Huang, He; Du, Jun; Zhu, Jian-Guo; Ren, Lu-Jing; Li, Shuang; Nie, Zhi-Kui

    2009-11-01

    An industrial medium containing urea as a sole nitrogen source, low levels of corn steep liquor and mineral salts as nutrition factors to retain high 2,3-butanediol production through co-fermentation of glucose and xylose (2:1, wt/wt) by Klebsiella oxytoca was developed. Urea and corn steep liquor were identified as the most significant factors by the two-level Plackett-Burman design. Steepest ascent experiments were applied to approach the optimal region of the two factors and a central composite design was employed to determine their optimal levels. Under the optimal medium, the yield of 2,3-butanediol plus acetoin relative to glucose and xylose was up to 0.428 g/g, which was 85.6% of theoretical value. The cheap nitrogen source and nutrition factors combining the co-fermentation process using lignocellulose derived glucose and xylose as the carbon source in the developed medium would be a potential solution to improve the economics of microbial 2,3-butanediol production.

  13. Process Optimization on Micro-Aeration Supply for High Production Yield of 2,3-Butanediol from Maltodextrin by Metabolically-Engineered Klebsiella oxytoca

    PubMed Central

    Jantama, Sirima Suvarnakuta; Kanchanatawee, Sunthorn

    2016-01-01

    An optimization process with a cheap and abundant substrate is considered one of the factors affecting the price of the production of economical 2,3-Butanediol (2,3-BD). A combination of the conventional method and response surface methodology (RSM) was applied in this study. The optimized levels of pH, aeration rate, agitation speed, and substrate concentration (maltodextrin) were investigated to determine the cost-effectiveness of fermentative 2,3-BD production by metabolically-engineered Klebsiella oxytoca KMS005. Results revealed that pH, aeration rate, agitation speed, and maltodextrin concentration at levels of 6.0, 0.8 vvm, 400 rpm, and 150 g/L respectively were the optimal conditions. RSM also indicated that the agitation speed was the most influential parameter when either agitation and aeration interaction or agitation and substrate concentration interaction played important roles for 2,3-BD production by the strain from maltodextrin. Under interim fed-batch fermentation, 2,3-BD concentration, yield, and productivity were obtained at 88.1±0.2 g/L, 0.412±0.001 g/g, and 1.13±0.01 g/L/h respectively within 78 h. PMID:27603922

  14. Metabolic changes in Klebsiella oxytoca in response to low oxidoreduction potential, as revealed by comparative proteomic profiling integrated with flux balance analysis.

    PubMed

    Zhu, Yan; Li, Dan; Bao, Guanhui; Wang, Shaohua; Mao, Shaoming; Song, Jiangning; Li, Yin; Zhang, Yanping

    2014-05-01

    Oxidoreduction potential (ORP) is an important physiological parameter for biochemical production in anaerobic or microaerobic processes. However, the effect of ORP on cellular physiology remains largely unknown, which hampers the design of engineering strategies targeting proteins associated with ORP response. Here we characterized the effect of altering ORP in a 1,3-propanediol producer, Klebsiella oxytoca, by comparative proteomic profiling combined with flux balance analysis. Decreasing the extracellular ORP from -150 to -240 mV retarded cell growth and enhanced 1,3-propanediol production. Comparative proteomic analysis identified 61 differentially expressed proteins, mainly involved in carbohydrate catabolism, cellular constituent biosynthesis, and reductive stress response. A hypothetical oxidoreductase (HOR) that catalyzes 1,3-propanediol production was markedly upregulated, while proteins involved in biomass precursor synthesis were downregulated. As revealed by subsequent flux balance analysis, low ORP induced a metabolic shift from glycerol oxidation to reduction and rebalancing of redox and energy metabolism. From the integrated protein expression profiles and flux distributions, we can construct a rational analytic framework that elucidates how (facultative) anaerobes respond to extracellular ORP changes.

  15. Structural insights into the broadened substrate profile of the extended-spectrum β-lactamase OXY-1-1 from Klebsiella oxytoca.

    PubMed

    Liang, Yu-He; Gao, Rong; Su, Xiao-Dong

    2012-11-01

    Klebsiella oxytoca is a pathogen that causes serious infections in hospital patients. It shows resistance to many clinically used β-lactam antibiotics by producing chromosomally encoded OXY-family β-lactamases. Here, the crystal structure of an OXY-family β-lactamase, OXY-1-1, determined at 1.93 Å resolution is reported. The structure shows that the OXY-1-1 β-lactamase has a typical class A β-lactamase fold and exhibits greater similarity to CTX-M-type β-lactamases than to TEM-family or SHV-family β-lactamases. It is also shown that the enzyme provides more space around the active cavity for the R(1) and R(2) substituents of β-lactam antibiotics. The half-positive/half-negative distribution of surface electrostatic potential in the substrate-binding pocket indicates the preferred properties of substrates or inhibitors of the enzyme. The results reported here provide a structural basis for the broadened substrate profile of the OXY-family β-lactamases.

  16. Wastewater drainage system as an occult reservoir in a protracted clonal outbreak due to metallo-β-lactamase-producing Klebsiella oxytoca.

    PubMed

    Vergara-López, S; Domínguez, M C; Conejo, M C; Pascual, Á; Rodríguez-Baño, J

    2013-11-01

    We describe the epidemiology of a protracted nosocomial clonal outbreak due to multidrug-resistant IMP-8 producing Klebsiella oxytoca (MDRKO) that was finally eradicated by removing an environmental reservoir. The outbreak occurred in the ICU of a Spanish hospital from March 2009 to November 2011 and evolved over four waves. Forty-two patients were affected. First basic (active surveillance, contact precautions and reinforcement of surface cleaning) and later additional control measures (nurse cohorting and establishment of a minimum patient/nurse ratio) were implemented. Screening of ICU staff was repeatedly negative. Initial environmental cultures, including dry surfaces, were also negative. The above measures temporarily controlled cross-transmission but failed to eradicate the epidemic MDRKO strain that reappeared two weeks after the last colonized patients in waves 2 and 3 had been discharged. Therefore, an occult environmental reservoir was suspected. Samples from the drainpipes and traps of a sink were positive; removal of the sink reduced the rate number but did not stop new cases that clustered in a cubicle whose horizontal drainage system was connected with the eliminated sink. The elimination of the horizontal drainage system finally eradicated the outbreak. In conclusion, damp environmental reservoirs (mainly sink drains, traps and the horizontal drainage system) could explain why standard cross-transmission control measures failed to control the outbreak; such reservoirs should be considered even when environmental cultures of surfaces are negative.

  17. First report of a novel extended-spectrum beta-lactamase KOXY-2 producing Klebsiella oxytoca that hydrolyses cefotaxime and ceftazidime.

    PubMed

    Younes, A; Hamouda, A; Amyes, S G B

    2011-06-01

    Klebsiella oxytoca strains MU946294N and MB193997E were isolated from patients in Scotland. Strain MU946294N was resistant to pencillins, monbactams and cephalosporins. Isolate MB193997E displayed a β-lactam resistance phenotype consistent with chromosomal β-lactamase overproduction. No bla(TEM), bla(SHV) or bla(CTX-M) genes could be amplified in either strain; however, amplification by PCR was found with primers for the bla(OXY-2) gene. This β-lactamase gene in MU946294N differed by one mutation from the all other bla(OXY) genes previously reported, with an amino acid substitution Alanine237 Threonine enhancing the binding of cefotaxime. Strain MB193997E showed mutations at positions 255 and 283, neither of which affect function. Based on rpoB and gyrA characterization, both strains were assigned to the KoII phylogenic group but they were completely dissimilar from each other by PFGE. This study is the first to report the substitution of Alanine to Threonine at position 237 in a OXY- 2 β-lactamase and this enhances resistance to cefotaxime.

  18. Process Optimization on Micro-Aeration Supply for High Production Yield of 2,3-Butanediol from Maltodextrin by Metabolically-Engineered Klebsiella oxytoca.

    PubMed

    Chan, Sitha; Jantama, Sirima Suvarnakuta; Kanchanatawee, Sunthorn; Jantama, Kaemwich

    2016-01-01

    An optimization process with a cheap and abundant substrate is considered one of the factors affecting the price of the production of economical 2,3-Butanediol (2,3-BD). A combination of the conventional method and response surface methodology (RSM) was applied in this study. The optimized levels of pH, aeration rate, agitation speed, and substrate concentration (maltodextrin) were investigated to determine the cost-effectiveness of fermentative 2,3-BD production by metabolically-engineered Klebsiella oxytoca KMS005. Results revealed that pH, aeration rate, agitation speed, and maltodextrin concentration at levels of 6.0, 0.8 vvm, 400 rpm, and 150 g/L respectively were the optimal conditions. RSM also indicated that the agitation speed was the most influential parameter when either agitation and aeration interaction or agitation and substrate concentration interaction played important roles for 2,3-BD production by the strain from maltodextrin. Under interim fed-batch fermentation, 2,3-BD concentration, yield, and productivity were obtained at 88.1±0.2 g/L, 0.412±0.001 g/g, and 1.13±0.01 g/L/h respectively within 78 h.

  19. Characterization of KPC-2-producing Escherichia coli, Citrobacter freundii, Enterobacter cloacae, Enterobacter aerogenes, and Klebsiella oxytoca isolates from a Chinese Hospital.

    PubMed

    Luo, Yanping; Yang, Jiyong; Ye, Liyan; Guo, Lin; Zhao, Qiang; Chen, Rong; Chen, Yong; Han, Xuelin; Zhao, Jingya; Tian, Shuguang; Han, Li

    2014-08-01

    Twelve nonduplicated KPC-2-producing enterobacterial isolates, including three Escherichia coli, two Citrobacter freundii, two Enterobacter cloacae, four Enterobacter aerogenes, and one Klebsiella oxytoca, were collected from various clinical samples within 18 months (March 2011 to September 2012). Two of the 12 patients died from infections caused by KPC-2-producing pathogens, while the rest of the patients with KPC-2-producing pathogens improved or were cured. The majority of the clinical isolates exhibited a high-level of resistance to oxyimino-cephalosporins and carbapenems, and possessed self-transferable bla(KPC-2)-carrying plasmids with sizes ranging from 20 to 120 kb. Most isolates carried bla(CTX-M) and plasmid-mediated quinolone resistance genes, while some isolates produced 16S rRNA methylases (ArmA or RmtB). The genetic environment of bla(KPC-2) of most clinical strains was consistent with the genetic structure surrounding bla(KPC-2) on the plasmid pKP048, which contains an integration structure of a Tn3-based transposon and partial Tn4401 segment. Inserted fragments (truncated bla(TEM)) were detected upstream of the bla(KPC-2) gene for two E. aerogenes strains. In conclusion, the enterobacterial isolates exhibited sporadic emergence and did not arise by clonal spread at our hospital. The outcome of infections caused by KPC-producing enterobacterial isolates and their mortality were closely associated with the baseline condition of patients. The spread of bla(KPC-2) gene between different enterobacterial species in China was mainly mediated by horizontal transfer of the Tn3-based transposons and not the bla(KPC-2)-carrying plasmids.

  20. Predatory Bacteria Attenuate Klebsiella pneumoniae Burden in Rat Lungs

    PubMed Central

    Singleton, Eric; Tang, Chi; Zuena, Michael; Shukla, Sean; Gupta, Shilpi; Dharani, Sonal; Onyile, Onoyom; Rinaggio, Joseph; Connell, Nancy D.

    2016-01-01

    ABSTRACT Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus are predatory bacteria that naturally—and obligately—prey on other Gram-negative bacteria, and their use has been proposed as a potential new approach to control microbial infection. The ability of predatory bacteria to prey on Gram-negative human pathogens in vitro is well documented; however, the in vivo safety and efficacy of predatory bacteria have yet to be fully assessed. In this study, we examined whether predatory bacteria can reduce bacterial burden in the lungs in an in vivo mammalian system. Initial safety studies were performed by intranasal inoculation of rats with predatory bacteria. No adverse effects or lung pathology were observed in rats exposed to high concentrations of predatory bacteria at up to 10 days postinoculation. Enzyme-linked immunosorbent assay (ELISA) of the immune response revealed a slight increase in inflammatory cytokine levels at 1 h postinoculation that was not sustained by 48 h. Additionally, dissemination experiments showed that predators were efficiently cleared from the host by 10 days postinoculation. To measure the ability of predatory bacteria to reduce microbial burden in vivo, we introduced sublethal concentrations of Klebsiella pneumoniae into the lungs of rats via intranasal inoculation and followed with multiple doses of predatory bacteria over 24 h. Predatory bacteria were able to reduce K. pneumoniae bacterial burden, on average, by more than 3.0 log10 in the lungs of most rats as measured by CFU plating. The work presented here provides further support for the idea of developing predatory bacteria as a novel biocontrol agent. PMID:27834203

  1. Simultaneous decolorization and biohydrogen production from xylose by Klebsiella oxytoca GS-4-08 in presence of azo dyes with sulfonate and carboxyl groups.

    PubMed

    Yu, Lei; Cao, Ming-Yue; Wang, Peng-Tao; Wang, Shi; Yue, Ying-Rong; Yuan, Wen-Duo; Qiao, Wei-Chuan; Wang, Fei; Song, Xin

    2017-03-10

    Biohydrogen production from the pulp and paper effluent containing rich lignocellulosic material could be achieved by the fermentation process. Xylose, an important hemicellulose hydrolysis product, is used less efficiently as a substrate for biohydrogen production. Moreover, azo dyes are usually added to fabricate anti-counterfeiting paper, which further increases the complexity of wastewater. This study is the first paper to report that xylose could serve as the sole carbon source for a pure culture-Klebsiella oxytoca GS-4-08 to achieve simultaneous decolorization and biohydrogen production. With 2 g l(-1) of xylose as the substrate, a maximum xylose utilization rate (URXyl) and a hydrogen molar yield (HMY) were obtained as 93.99% and 0.259 mol H2 mol(-1) xylose, respectively. Biohydrogen kinetics and e(-) equiv balance calculations indicated that MR penetrates and intracellularly inhibits on both pentose phosphate pathway and pyruvate fermentation pathway, while MO was independent of the glycolysis and biohydrogen pathway. The data demonstrate that biohydrogen pathways in the presence of azo dyes with sulfonate and carboxyl groups were different, but the azo dyes could be completely reduced during the biohydrogen production period whether with the presence of MO or MR. The feasibility of hydrogen production from industrial pulp and paper effluent by the strain was also proved if the xylose is sufficient, and not affected by toxic substances which usually exists in such wastewater except for chlorophenol. This study offers a promising energy-recycling strategy for treating pulp and paper wastewaters, especially for those containing azo dyes.Importance The pulp and paper industry is a major industry in many developing countries and the global market of pulp and paper wastewater treatment is expected to increase by 60% between 2012 and 2020. Such wastewater contains large amount of refractory contaminants, such as lignin, whose reclamation is considered economic

  2. Enhanced H2 gas production from bagasse using adhE inactivated Klebsiella oxytoca HP1 by sequential dark-photo fermentations.

    PubMed

    Wu, Xiaobing; Li, Qianyi; Dieudonne, Mutangana; Cong, Yibo; Zhou, Juan; Long, Minnan

    2010-12-01

    Sequential dark-photo fermentations (SDPF) was used for hydrogen production from bagasse, an acetaldehyde dehydrogenase (adhE) gene inactivated Klebsiella oxytoca HP1 (DeltaadhE HP1) mutant was used to reduce the alcohol content in dark fermentation (DF) broths and to further enhance the hydrogen yield during the photo fermentation (PF) stage. Compared with that of the wild strain, the ethanol concentration in DF broths of DeltaadhE HP1 decreased 69.4%, which resulted in a hydrogen yield in the PF stage and the total hydrogen yield over the two steps increased by 54.7% and 23.5%, respectively. The culture conditions for hydrogen production from acid pretreated bagasse by SDPF were optimized as culture temperature 37.5 degrees C, initial pH 7.0, and cellulase loading 20 FPA/g in the DF stage, with initial pH 6.5, temperature 30 degrees C and photo intensity 5,000 lux in the PF stage. Under optimum conditions, by using DeltaadhE HP1 and wild type strain, the H(2) yields were 107.8+/-5.3 mL H(2)/g-bagasse, 96.2+/-4.4 mL H(2)/g-bagasse in DF and 54.3+/-2.2 mL H(2)/g-bagasse, 35.1+/-2.0 mL H(2)/g-bagasse in PF, respectively. The special hydrogen production rate (SHPR) were 5.51+/-0.34 mL H(2)/g-bagasseh, 4.95+/-0.22 mL H(2)/g-bagasseh in DF and 0.93+/-0.12 mL H(2)/g-bagasseh, 0.59+/-0.07 mL H(2)/g-bagasseh in PF, respectively. The total hydrogen yield from bagasse over two steps was 162.1+/-7.5 mL H(2)/g-bagasse by using DeltaadhE HP1, which was 50.4% higher than that from dark fermentation only. These results indicate that reducing ethanol content during dark fermentation by using an adhE inactivated strain can significantly enhance hydrogen production from bagasse in the SDPF system. This work also proved that SDPF was an effective way to improve hydrogen production from bagasse.

  3. Hexavalent molybdenum reduction to mo-blue by a sodium-dodecyl-sulfate-degrading Klebsiella oxytoca strain DRY14.

    PubMed

    Halmi, M I E; Zuhainis, S W; Yusof, M T; Shaharuddin, N A; Helmi, W; Shukor, Y; Syed, M A; Ahmad, S A

    2013-01-01

    Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously are urgently needed for remediation of polluted sites. A previously isolated bacterium with sodium dodecyl sulfate- (SDS-) degrading capacity was found to be able to reduce molybdenum to the nontoxic molybdenum blue. The optimal pH, carbon source, molybdate concentration, and temperature supporting molybdate reduction were pH 7.0, glucose at 1.5% (w/v), between 25 and 30 mM, and 25°C, respectively. The optimum phosphate concentration for molybdate reduction was 5 mM. The Mo-blue produced exhibits an absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. None of the respiratory inhibitors tested showed any inhibition to the molybdenum-reducing activity suggesting that the electron transport system of this bacterium is not the site of molybdenum reduction. Chromium, cadmium, silver, copper, mercury, and lead caused approximately 77, 65, 77, 89, 80, and 80% inhibition of the molybdenum-reducing activity, respectively. Ferrous and stannous ions markedly increased the activity of molybdenum-reducing activity in this bacterium. The maximum tolerable concentration of SDS as a cocontaminant was 3 g/L. The characteristics of this bacterium make it a suitable candidate for molybdenum bioremediation of sites cocontaminated with detergent pollutant.

  4. Hexavalent Molybdenum Reduction to Mo-Blue by a Sodium-Dodecyl-Sulfate-Degrading Klebsiella oxytoca Strain DRY14

    PubMed Central

    Halmi, M. I. E.; Zuhainis, S. W.; Yusof, M. T.; Shaharuddin, N. A.; Helmi, W.; Shukor, Y.; Syed, M. A.; Ahmad, S. A.

    2013-01-01

    Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously are urgently needed for remediation of polluted sites. A previously isolated bacterium with sodium dodecyl sulfate- (SDS-) degrading capacity was found to be able to reduce molybdenum to the nontoxic molybdenum blue. The optimal pH, carbon source, molybdate concentration, and temperature supporting molybdate reduction were pH 7.0, glucose at 1.5% (w/v), between 25 and 30 mM, and 25°C, respectively. The optimum phosphate concentration for molybdate reduction was 5 mM. The Mo-blue produced exhibits an absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. None of the respiratory inhibitors tested showed any inhibition to the molybdenum-reducing activity suggesting that the electron transport system of this bacterium is not the site of molybdenum reduction. Chromium, cadmium, silver, copper, mercury, and lead caused approximately 77, 65, 77, 89, 80, and 80% inhibition of the molybdenum-reducing activity, respectively. Ferrous and stannous ions markedly increased the activity of molybdenum-reducing activity in this bacterium. The maximum tolerable concentration of SDS as a cocontaminant was 3 g/L. The characteristics of this bacterium make it a suitable candidate for molybdenum bioremediation of sites cocontaminated with detergent pollutant. PMID:24383052

  5. EFFECTS OF VELOCITY ON THE TRANSPORT OF TWO BACTERIA THROUGH SATURATED SAND. GROUND WATER.

    EPA Science Inventory

    Transport of the bacteria Klebsiella oxytoca and Burkholderia cepacia G4PR1 (G4PR1) was investigated in column experiments conducted under conditions that allowed us to quantify sorption under a range of ground water velocities. Column experiments (33 mm I.D. X 114 mm long colu...

  6. On the evolution of the sexually transmitted bacteria Haemophilus ducreyi and Klebsiella granulomatis.

    PubMed

    Lagergård, Teresa; Bölin, Ingrid; Lindholm, Leif

    2011-08-01

    Haemophilus ducreyi and Klebsiella (Calymmatobacterium) granulomatis are sexually transmitted bacteria that cause characteristic, persisting ulceration on external genitals called chancroid and granuloma inguinale, respectively. Those ulcers are endemic in developing countries or exist, as does granuloma inguinale, only in some geographic "hot spots."H. ducreyi is placed in the genus Haemophilus (family Pasteurellacae); however, this phylogenetic position is not obvious. The multiple ways in which the bacterium may be adapted to its econiche through specialized nutrient acquisitions; defenses against the immune system; and virulence factors that increase attachment, fitness, and persistence within genital tissue are discussed below. The analysis of K. granulomatis phylogeny demonstrated a high degree of identity with other Klebsiella species, and the name K. granulomatis comb. nov. was proposed. Because of the difficulty in growing this bacterium on artificial media, its characteristics have not been sufficiently defined. More studies are needed to understand bacterial genetics related to the pathogenesis and evolution of K. granulomatis.

  7. Protective effect of Klebsiella bacteria on lawn grasses under conditions of soil salinization

    NASA Astrophysics Data System (ADS)

    Emtsev, V. T.; Sokolova, A. Ya.; Selitskaya, O. V.

    2010-07-01

    The protective effect of the inoculation of lawn grasses grown under conditions of soil salinization with bacteria of the Klebsiella genus ( K. planticola and K. pneumoniae) was demonstrated. It was found that K. pneumoniae improves the plant growth under conditions of a high concentration of sodium chloride. It was also shown that the inoculation of lawn grasses with these bacteria optimizes the morphophysiological parameters of the plants and increases the number of mitoses in the apical parts of the roots, which leads to a less significant decrease in the mitotic index under the impact of salinization. The capacity of K. planticola to penetrate into the plants may favor the activation of protective mechanisms improving the immunological status of the plants and, hence, their tolerance to salinization.

  8. Efficient reduction of the formation of by-products and improvement of production yield of 2,3-butanediol by a combined deletion of alcohol dehydrogenase, acetate kinase-phosphotransacetylase, and lactate dehydrogenase genes in metabolically engineered Klebsiella oxytoca in mineral salts medium.

    PubMed

    Jantama, Kaemwich; Polyiam, Pattharasedthi; Khunnonkwao, Panwana; Chan, Sitha; Sangproo, Maytawadee; Khor, Kirin; Jantama, Sirima Suvarnakuta; Kanchanatawee, Sunthorn

    2015-07-01

    Klebsiella oxytoca KMS005 (∆adhE∆ackA-pta∆ldhA) was metabolically engineered to improve 2,3-butanediol (BDO) yield. Elimination of alcohol dehydrogenase E (adhE), acetate kinase A-phosphotransacetylase (ackA-pta), and lactate dehydrogenase A (ldhA) enzymes allowed BDO production as a primary pathway for NADH re-oxidation, and significantly reduced by-products. KMS005 was screened for the efficient glucose utilization by metabolic evolution. KMS005-73T improved BDO production at a concentration of 23.5±0.5 g/L with yield of 0.46±0.02 g/g in mineral salts medium containing 50 g/L glucose in a shake flask. KMS005-73T also exhibited BDO yields of about 0.40-0.42 g/g from sugarcane molasses, cassava starch, and maltodextrin. During fed-batch fermentation, KMS005-73T produced BDO at a concentration, yield, and overall and specific productivities of 117.4±4.5 g/L, 0.49±0.02 g/g, 1.20±0.05 g/Lh, and 27.2±1.1 g/gCDW, respectively. No acetoin, lactate, and formate were detected, and only trace amounts of acetate and ethanol were formed. The strain also produced the least by-products and the highest BDO yield among other Klebsiella strains previously developed.

  9. [DISTRIBUTION OF BACTERIA OF THE KLEBSIELLA STRAIN IN WATER OBJECTS AND THEIR VALUE IN DEVELOPING OF THE WATER CAUSED ACUTE INTESTINAL INFECTIONS].

    PubMed

    Rakhmanin, Yu A; Ivanova, L V; Artyomova, T Z; Gipp, E K; Zagaynova, A V; Maksimkina, T N; Krasnyak, A V; Zhuravlev, P V; Aleshnya, V V; Panasovets, O P

    2016-01-01

    The wide circulation of Klebsiella bacteria in water ofwater objects of different climatic zones of Russia and various function is established. So bacteria of the Klebsiella strain are in superficial sources of the centralized water supply depending on extent of their biological and chemical pollution; underground waters at the unprotected water-bearing horizons; in drinking water at insufficiently effective system of its cleaning and disinfecting. Klebsiella circulating in water was shown to keep properties of pathogenicity and a virulence, possess resistance both to modern preparations and disinfecting agents (chlorine, an ultraviolet to radiation). Bacteria of the Klebsiella strain have high penetration in the water-bearing horizons. At strains of Klebsiella there is allocated considerable pathogenic potential (adhesive, invasive, phosphatase, lecithinase, DNA-ase, hemolytic activity) and genetic markers of pathogenicity of cnf-1. The etiologic role of bacteria of Klebsiella and an infecting (100, COE/dm3) dose emergence of acute intestinal infections (AII) is established. Detection of Klebsiella in water objects and especially in water of drinking appointment, in the absence of total coliform bacteria (TCB) contributes to the epidemic danger of water use.

  10. Plugging of a model rock system by using starved bacteria. [Klebsiella pneumoniae

    SciTech Connect

    MacLeod, F.A.; Lappin-Scott, H.M.; Costerton, J.W.

    1988-06-01

    The effects of starvation on bacterial penetration through artificial rock cores were examined. Klebsiella pneumoniae was starved in a simple salts solution for a duration of up to 4 weeks. These cell suspensions were injected into sintered glass bead cores, and the resulting reductions in core permeabilities were recorded. Vegetative cell cultures of K. pneumoniae grown in a sodium citrate medium were injected into other, similar cores, and the reductions in core permeabilities were recorded. The starved cell suspensions did not completely block the core pores, whereas the vegetative cultures reduced core permeability to less than 1%. Scanning electron microscopy of core section infiltrated with either vegetative or starved cells showed that the former produced shallow skin plugs and copious amounts of glycocalyx at the inlet face, whereas the latter produced very little glycocalyx and the cells were distributed evenly throughout the length of the core. The use of a DNA assay to produce a cell distribution profile showed that, compared with the vegetative cells, starved bacteria were able to penetrate deeper into the cores. This was due to the smaller size of the cells and the reduction in biofilm production. This ability of starved bacteria to penetrate further into cores than the normal-size vegetative cells can be usefully applied to selective plugging for enhanced oil recovery. To further test the suitability of starved cells for use in selective plugging, the activities of starved cells present within cores were monitored before and after nutrient stimulation. Our data indicate that with nutrient stimulation, the starved cells lose their metabolic dormancy and produce reductions in core permeability due to cell growth and polymer production.

  11. Vaccination with Klebsiella pneumoniae-derived extracellular vesicles protects against bacteria-induced lethality via both humoral and cellular immunity

    PubMed Central

    Lee, Won-Hee; Choi, Hyun-Il; Hong, Sung-Wook; Kim, Kwang-sun; Gho, Yong Song; Jeon, Seong Gyu

    2015-01-01

    The emergence of multidrug-resistant Klebsiella pneumoniae highlights the need to develop preventive measures to ameliorate Klebsiella infections. Bacteria-derived extracellular vesicles (EVs) are spherical nanometer-sized proteolipids enriched with outer membrane proteins. Gram-negative bacteria-derived EVs have gained interest for use as nonliving complex vaccines. In the present study, we evaluated whether K. pneumoniae-derived EVs confer protection against bacteria-induced lethality. K. pneumoniae-derived EVs isolated from in vitro bacterial culture supernatants induced innate immunity, including the upregulation of co-stimulatory molecule expression and proinflammatory mediator production. EV vaccination via the intraperitoneal route elicited EV-reactive antibodies and interferon-gamma-producing T-cell responses. Three vaccinations with the EVs prevented bacteria-induced lethality. As verified by sera and splenocytes adoptive transfer, the protective effect of EV vaccination was dependent on both humoral and cellular immunity. Taken together, these findings suggest that K. pneumoniae-derived EVs are a novel vaccine candidate against K. pneumoniae infections. PMID:26358222

  12. First Report of Septic Arthritis Caused by Klebsiella oxytoca▿

    PubMed Central

    Ménard, Armelle; Harambat, Jérome; Pereyre, Sabine; Pontailler, Jean-Roger; Mégraud, Francis; Richer, Olivier

    2010-01-01

    Klebsiella oxytoca is known to be a pathogen in immunodeficient adults and children. Here we report the first case of a K. oxytoca infection associated with spontaneous arthritis of the knee in a child with no history of immunosuppressive therapy or previous bacterial infections. Despite an initial antibiotic treatment failure, a second treatment led to a cure of the infection with no joint sequelae. PMID:20573877

  13. Molecular characterization of class 1 integrons and gene cassettes in multidrug resistant (MDR) Klebsiella spp. isolated from hospitalized and outpatients in Iran, 2009

    PubMed Central

    Salimizand, Himen; Shahcheraghi, Fereshteh; Kalantar, Enayatollah; Badmasti, Farzad

    2013-01-01

    Background and objectives Klebsiella species are of the most common bacteria involved in nosocomial and urinary tract infections. Genetic elements such as class 1 integrons have an important role in the resistance development. In this study, the share of class 1 integrons, the genetic characterization of the integron cassettes and PFGE profiles of the clinical Klebsiella isolates are evaluated in Besat University hospital of Sanandaj, Iran. Methods Isolates from 17890 clinical specimens were identified by API20E. Antibiotic susceptibility testing and MIC were done for MDR isolates. For investigating class 1 integrons and gene cassettes, PCR by intI1 integrase and 5’-CS/3’-CS were performed. Integrated gene cassettes were analyzed by PCR-RFLP and sequencing. Pulsed-Field Gel Electrophoresis was carried out for studying of clonality outbreak of isolates. Results Thirty five Klebsiella spp. were isolated and included 29 K. pneumoniae and 6 K. oxytoca. All the isolates were susceptible to carbapenems while other antibiotics showed high resistant profile. In all Klebsiella spp. PCR for intI1 integrase and 5’-CS/3’-CS were positive (100%). Sequencing for prevalent bands of internal variable regions between 5’-CS/3’-CS showed arr-5, orfD-aacA4 and aad5- dfrA17. PFGE Analysis showed 18 clusters in K. pneumoniae with clonality relatedness in some cases but no relatedness among K. oxytoca isolates. Conclusion High prevalence of class 1 integron carrying gene cassettes confirms that integron-mediated antimicrobial gene cassettes are important in Klebsiella spp. resistance profile. Clone diffusions of MDR Klebsiella spp. which harbor class 1 integrons have threaten the potential in the resistance development in our clinical settings. PMID:23466743

  14. Cultivable endophytic bacteria from leaf bases of Agave tequilana and their role as plant growth promoters

    PubMed Central

    Martínez-Rodríguez, Julia del C.; la Mora-Amutio, Marcela De; Plascencia-Correa, Luis A.; Audelo-Regalado, Esmeralda; Guardado, Francisco R.; Hernández-Sánchez, Elías; Peña-Ramírez, Yuri J.; Escalante, Adelfo; Beltrán-García, Miguel J.; Ogura, Tetsuya

    2014-01-01

    Agave tequilana Weber var. ‘Azul’ is grown for the production of tequila, inulin and syrup. Diverse bacteria inhabit plant tissues and play a crucial role for plant health and growth. In this study culturable endophytic bacteria were extracted from leaf bases of 100 healthy Agave tequilana plants. In plant tissue bacteria occurred at mean population densities of 3 million CFU/g of fresh plant tissue. Three hundred endophytic strains were isolated and 16s rDNA sequences grouped the bacteria into eight different taxa that shared high homology with other known sequences. Bacterial endophytes were identified as Acinectobacter sp., A. baumanii, A. bereziniae, Cronobacter sakazakii, Enterobacter hormaechei, Bacillus sp. Klebsiella oxytoca, Pseudomonas sp., Enterococcus casseliflavus, Leuconostoc mesenteroides subsp. mesenteroides and Gluconobacter oxydans. Isolates were confirmed to be plant growth promoting bacteria (PGPB) by their capacities for nitrogen fixation, auxin production, phosphate solubilization, or antagonism against Fusarium oxysporum AC132. E. casseliflavus JM47 and K. oxytoca JM26 secreted the highest concentrations of IAA. The endophyte Acinectobacter sp. JM58 exhibited the maximum values for nitrogen fixation and phosphate solubilization index (PSI). Inhibition of fungi was found in Pseudomonas sp. JM9p and K. oxytoca JM26. Bacterial endophytes show promise for use as bio-inoculants for agave cultivation. Use of endophytes to enhance cultivation of agave may be particularly important for plants produced by micropropagation techniques, where native endophytes may have been lost. PMID:25763038

  15. Cultivable endophytic bacteria from leaf bases of Agave tequilana and their role as plant growth promoters.

    PubMed

    Martínez-Rodríguez, Julia del C; De la Mora-Amutio, Marcela; Plascencia-Correa, Luis A; Audelo-Regalado, Esmeralda; Guardado, Francisco R; Hernández-Sánchez, Elías; Peña-Ramírez, Yuri J; Escalante, Adelfo; Beltrán-García, Miguel J; Ogura, Tetsuya

    2014-01-01

    Agave tequilana Weber var. 'Azul' is grown for the production of tequila, inulin and syrup. Diverse bacteria inhabit plant tissues and play a crucial role for plant health and growth. In this study culturable endophytic bacteria were extracted from leaf bases of 100 healthy Agave tequilana plants. In plant tissue bacteria occurred at mean population densities of 3 million CFU/g of fresh plant tissue. Three hundred endophytic strains were isolated and 16s rDNA sequences grouped the bacteria into eight different taxa that shared high homology with other known sequences. Bacterial endophytes were identified as Acinectobacter sp., A. baumanii, A. bereziniae, Cronobacter sakazakii, Enterobacter hormaechei, Bacillus sp. Klebsiella oxytoca, Pseudomonas sp., Enterococcus casseliflavus, Leuconostoc mesenteroides subsp. mesenteroides and Gluconobacter oxydans. Isolates were confirmed to be plant growth promoting bacteria (PGPB) by their capacities for nitrogen fixation, auxin production, phosphate solubilization, or antagonism against Fusarium oxysporum AC132. E. casseliflavus JM47 and K. oxytoca JM26 secreted the highest concentrations of IAA. The endophyte Acinectobacter sp. JM58 exhibited the maximum values for nitrogen fixation and phosphate solubilization index (PSI). Inhibition of fungi was found in Pseudomonas sp. JM9p and K. oxytoca JM26. Bacterial endophytes show promise for use as bio-inoculants for agave cultivation. Use of endophytes to enhance cultivation of agave may be particularly important for plants produced by micropropagation techniques, where native endophytes may have been lost.

  16. Influence of Asellus aquaticus on Escherichia coli, Klebsiella pneumoniae, Campylobacter jejuni and naturally occurring heterotrophic bacteria in drinking water.

    PubMed

    Christensen, Sarah C B; Nissen, Erling; Arvin, Erik; Albrechtsen, Hans-Jørgen

    2012-10-15

    Water lice, Asellus aquaticus (isopoda), frequently occur in drinking water distribution systems where they are a nuisance to consumers and water utilities. Whether they are solely an aesthetic problem or also affect the microbial water quality is a matter of interest. We studied the influence of A. aquaticus on microbial water quality in non-chlorinated drinking water in controlled laboratory experiments. Pure cultures of the indicator organisms Escherichia coli and Klebsiella pneumoniae and the pathogen Campylobacter jejuni as well as naturally occurring heterotrophic drinking water bacteria (measured as heterotrophic plate counts, HPC) were investigated in microcosms at 7 °C, containing non-sterilised drinking water, drinking water sediment and A. aquaticus collected from a non-chlorinated ground water based drinking water supply system. Concentrations of E. coli, K. pneumoniae and C. jejuni decreased over time, following a first order decay with half lives of 5.3, 18.4 and 1.3 days, respectively. A. aquaticus did not affect survival of indicators and pathogens substantially whereas HPC were influenced by presence of dead A. aquaticus. Growth rates increased with an average of 48% for bacteria grown on R-2A agar and an average of 83% for bacteria grown on yeast extract agar when dead A. aquaticus were present compared to no and living A. aquaticus present. A. aquaticus associated E. coli, K. pneumoniae and C. jejuni were measured (up to 25 per living and 500 per dead A. aquaticus) and so were A. aquaticus associated heterotrophic bacteria (>1.8*10(4) CFU per living and >6*10(4) CFU per dead A. aquaticus). A. aquaticus did not serve as an optimised habitat that increased survival of indicators and pathogens, since A. aquaticus associated E. coli, K. pneumoniae and C. jejuni were only measured as long as the bacteria were also present in the water and sediment.

  17. Fermentation of polysaccharides by Klebsiella and other facultative bacilli

    SciTech Connect

    Ochuba, G.U.; Von Riesen, V.L.

    1980-05-01

    Fermentations of 10 polysaccharides by species of the family Enterobacteriaceae were examined. Algin, guar, karaya, xanthan, and xylan were not fermented by any of the strains tested. Most of the activity was found in the tribe Klebsielleae. Klebseilla oxytoca fermented amylopectin (97% of the strains studied), carrageenan (100%), inulin (68%), polypectate (100%), and tragacanth (100%). Klebsiella pneumoniae fermented amylopectin (91%), carrageenan (100%), and tragacanth (86%). Carraggeenan was also fermented by Enterobacter aerogenes (100%), Enterobacter agglomerans (63%), Enterobacter cloacae (95%), and pectobacterium (38%). pectobacterium shared polypectate fermentation (100%) with K. oxytoca. With one exception, Serratia strains were negative on all polysaccharides. These results, along with other evidence, indicate that (i) the genus Klebsiella is biochemically the most versatile genus of the tribe, (ii) because of its distinct characteristics, K. oxytoca warrants species designation separate from K. pneumoniae, and (iii) some food additives generally considered indigestible can be metabolized by a few species of facultative bacilli, whereas others appear to be resistant.

  18. Rarity of transferable beta-lactamase production by Klebsiella species.

    PubMed

    Leung, M; Shannon, K; French, G

    1997-06-01

    We report a survey of beta-lactamases and their transferability in Klebsiella spp. isolated from blood during 1992-95. beta-Lactamases were characterized by determination of isoelectric point (pI), by hybridization of plasmid DNA preparations with probes for SHV and TEM sequences and by PCR with SHV- or TEM-specific primers. There were 80 isolates of Klebsiella pneumoniae and 22 isolates of Klebsiella oxytoca. Most isolates of K. pneumoniae had a chromosomally encoded SHV-1 beta-lactamase (or a closely related enzyme); K. oxytoca also produced chromosomal beta-lactamases, but these were distinct from SHV-1. Plasmid-encoded beta-lactamases were rare in Klebsiella spp., being found in six (7.5%) isolates of K. pneumoniae and in none of the K. oxytoca. beta-Lactamase activities were relatively low (< 100 nmoles nitrocefin hydrolysed per minute per mg of protein) and ampicillin MICs were < or = 128 mg/L for most isolates of both species. However, all isolates of K. pneumoniae with plasmid-encoded beta-lactamases, three other isolates of K. pneumoniae and three isolates of K. oxytoca had high beta-lactamase activities (> 100 nmoles/mg/min) and very high ampicillin MICs (> or = 1024 mg/L).

  19. [THE CHROMOGENIC SYNTHETIC MEDIUM "KLEBSIELLA 5-ASK CHROM-C" FOR ISOLATION AND IDENTIFICATION OF KLEBSIELLAE].

    PubMed

    Sivolodskii, E P

    2015-05-01

    The chromogenic synthetic medium "Klebsiella 5-ASK CHROM-C was developedfor isolation and identification of klebsiellae of species of K. pneumoniae subsp. pneumoniae K. oxytoca, K. mobilis according chromogenic reaction to enzyme 5-aminosalycilate decarboxylase as a unique marker of genus Klebsiella. The L-proline and L-calcium glutamate are used as a source of nitrogen and carbon in medium. The consistency of composition of growth medium that ensure its regularity. The diagnostic sensitivity of chromogenic medium is 95.3 ± 1.7%; diagnostic specificity is 100%; analytical sensitivity is 1-2 colony-forming units per ml-1. The identification of Klebsiella is achieved simultaneously with their isolation during 24 = 48 hours. The test of 5-ASK decarboxylase using two chromogenic mediums "Klebsiella 5-ASK CHROM-C" permits identifying additionally K. pneumoniae subsp, ozaenae, K .pneumoniae subsp. Rhinoscleromatis.

  20. Low Diversity Bacterial Community and the Trapping Activity of Metabolites from Cultivable Bacteria Species in the Female Reproductive System of the Oriental Fruit Fly, Bactrocera dorsalis Hendel (Diptera: Tephritidae)

    PubMed Central

    Shi, Zhanghong; Wang, Lili; Zhang, Hongyu

    2012-01-01

    Our goal was to identify the bacteria inhabiting the reproductive system of the female oriental fruit fly, Bactrocera dorsalis (Hendel), and evaluate the chemotaxis of B. dorsalis to the metabolites produced by the bacteria. Based on 16S rRNA-based polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), 18 operational taxonomic units (OTUs) were assigned to the five bacterial classes Betaproteobacteria, Alphaproteobacteria, Gammaproteobacteria, Bacilli and Actinobacteria. Nine OTUs were assigned to Gammaproteobacteria, which was the most highly represented class. Enterobacteriaceae constituted the dominant family, and within this family, three genera and five species were identified, including Enterobacter sakazakii, Klebsiella oxytoca, Klebsiella pneumoniae, Raoultella terrigena and Enterobacter amnigenus. In this set, the first two species were the dominant components, and the latter three species were the minor ones. Finally, we found that the metabolites produced by R. terrigena, K. oxytoca and K. pneumoniae were attractive to the B. dorsalis adults, and in field studies, B. dorsalis adults were most attracted to K. oxytoca. Collectively, our results suggest that the female reproductive system plays an important role in the transfer of enterobacteria from the gut to fruit. Our data may prompt the development of a female-targeted population control strategy for this fly. PMID:22754363

  1. Commensal Bacteria Aid Mate-selection in the Fruit Fly, Bactrocera dorsalis.

    PubMed

    Damodaram, Kamala Jayanthi Pagadala; Ayyasamy, Arthikirubha; Kempraj, Vivek

    2016-10-01

    Commensal bacteria influence many aspects of an organism's behaviour. However, studies on the influence of commensal bacteria in insect mate-selection are scarce. Here, we present empirical evidence that commensal bacteria mediate mate-selection in the Oriental fruit fly, Bactrocera dorsalis. Male flies were attracted to female flies, but this attraction was abolished when female flies were fed with antibiotics, suggesting the role of the fly's microbiota in mediating mate-selection. We show that male flies were attracted to and ejaculated more sperm into females harbouring the microbiota. Using culturing and 16S rDNA sequencing, we isolated and identified different commensal bacteria, with Klebsiella oxytoca being the most abundant bacterial species. This preliminary study will enhance our understanding of the influence of commensal bacteria on mate-selection behaviour of B. dorsalis and may find use in devising control operations against this devastating pest.

  2. Vaccination against Klebsiella aerogenes.

    PubMed Central

    Roe, E. A.; Jones, R. J.

    1984-01-01

    Klebsiella vaccine was prepared from strains of Klebsiella aerogenes with capsular types K1, K36, K44 and K Cross (a type which cross-reacts in vitro with sera from many klebsiella capsular types). The vaccine was extracted by dialysis and ultrafiltration from capsular material released during growth of the bacteria in a five-day batch culture. Mice given one dose of vaccine from K1a (1.0 microgram/mouse) survived lethal intraperitoneal challenge of 11/11 homologous klebsiella strains four days after vaccination; 14 days after vaccination protection against the same challenge strains had declined to 5/11 strains. Vaccines from K1a, b, c, K36, K44 and K Cross induced homologous protection and protected mice against different ranges of heterologous klebsiella capsular types. The protective response of the mice was greatly enhanced by administering three doses of the vaccines. Vaccines from K1, K36, K44 and K Cross protected mice against 14/20, 11/20, 10/20 and 9/20 homologous and heterologous klebsiella challenge strains respectively. None of the klebsiella vaccines was toxic for mice at the immunizing dose (1.0 microgram/mouse). Vaccine from K36 was the most lethal, killing mice at 10(3) immunizing doses. The least toxic vaccine was from K44, which killed mice at 10(4) immunizing doses. PMID:6389699

  3. Community spread of extended-spectrum β-lactamase-producing bacteria detected in social insurance hospitals throughout Japan.

    PubMed

    Shibasaki, Mayumi; Komatsu, Masaru; Sueyoshi, Noriyuki; Maeda, Misaho; Uchida, Takae; Yonezawa, Hitoshi; Inagaki, Kenji; Omi, Ayako; Matsumoto, Hidenobu; Murotani, Makiko; Iwamoto, Tsukasa; Kodaka, Yoshihiro; Kieda, Hideto; Tokiwa, Manabu; Masuwa, Bunji; Kinoshita, Mari; Saito, Kazuei; Katou, Masahiko

    2016-06-01

    We surveyed the status of community-acquired infections involving four extended-spectrum β-lactamase (ESBL)-producing bacteria (Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis) isolated from clinical specimens from 11 social insurance hospitals in Japan in 2012. These are member hospitals of the Japan Community Healthcare Organization, an independent administrative hospital organization. The isolation rates for E. coli, K. pneumoniae, K. oxytoca, and P. mirabilis were 14.0% (165/1176), 3.3% (16/480), 3.1% (4/130), and 15.9% (17/107), respectively. The CTX-M-9 group, the most frequently detected genotype, was found in 77.0% (127/165) of E. coli and 43.8% (7/16) of K. pneumoniae isolates. Among K. oxytoca isolates, 75% (3/4) were the CTX-M-1 group, and all 17 P. mirabilis strains were the CTX-M-2 group. ESBL-producing bacteria isolation rates in each hospital ranged from 5.8% to 21.5% (median 9.5%), and the proportion of community-acquired infections among ESBL-producing bacteria isolates ranged from 1.6% to 30.8% (median 11.4%) in each hospital. Overall, the rates of ESBL-producing bacterial infection in all community-acquired infections and in all hospital infections were 10.6% (115/1081) and 10.7% (87/812), respectively. The ESBL-producing bacteria are not limited to certain regions or hospitals but are spreading in communities throughout Japan.

  4. Prevalence of multidrug resistant uropathogenic bacteria in pediatric patients of a tertiary care hospital in eastern India.

    PubMed

    Mishra, Monali P; Sarangi, Rachita; Padhy, Rabindra N

    2016-01-01

    Today, because systemic infections such as urinary tract infection (UTI) affect even pediatric patients, antibiotic resistant bacteria have become a constant clinical challenge. In the present study, a total of 1054 urine samples were collected from pediatric patients over 18 months. From these samples, 510 isolates of pathogenic bacteria were collected using HiCrome UTI agar. Antibiotic sensitivity tests of isolates were performed using the Kirby-Bauer method. Two Gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus) and 7 Gram-negative bacteria (Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella oxytoca, K. pneumoniae, Proteus vulgaris and Pseudomonas aeruginosa) were isolated. Antibiograms of isolated bacteria were ascertained using antibiotics of 4 classes: aminoglycosides, β-lactams, fluoroquinolones and 2 stand-alones (co-trimoxazole and nitrofurantoin). Based on percent values of antibiotic resistance, isolated bacteria were (in decreasing order of number of isolated isolates): E. coli (109)>S. aureus (65)>E. faecalis (82)>E. aerogenes (64)>C. freundii (41)>P. aeruginosa (32)>K. pneumoniae (45)>K. oxytoca (50)>P. vulgaris (22). Surveillance results show that MDR isolates of 9 pathogenic bacteria were prevalent in the environment around the hospital. Thus, revisions to the antimicrobial stewardship program in this area of the country are required to increase clinician confidence in empiric therapy, which is often used for UTI cases.

  5. Antibiotic Susceptibility of Commensal Bacteria from Human Milk.

    PubMed

    Chen, Po-Wen; Tseng, Shu-Ying; Huang, Mao-Sheng

    2016-02-01

    Recent studies have focused on foodborne or commensal bacteria as vehicles of antibiotic resistance. However, the antibiotic resistance of milk bacteria from healthy donors is still vague in Taiwan. For this purpose, human milk samples were obtained from randomly recruited 19 healthy women between 3 and 360 days post-partum. Antibiotic susceptibility profile of bacteria from milk samples was determined. About 20 bacterial species were isolated from milk samples including Staphylococcus (6 species), Streptococcus (4 species), Enterococcus (2 species), Lactobacillus (1 species), and bacteria belonging to other genera (7 species). Some opportunistic or potentially pathogenic bacteria including Kluyvera ascorbata, Klebsiella oxytoca, Klebsiella pneumoniae, Acinetobacter baumannii, Actinomyces bovis, and Staphylococcus aureus were also isolated. Intriguingly, Staphylococcus isolates (22 strains) were resistant to 2–8 of 8 antibiotics, while Streptococcus isolates (3 strains) were resistant to 3–7 of 9 antibiotics, and members of the genus Enterococcus (5 strains) were resistant to 3–8 of 9 antibiotics. Notably, Staphylococcus lugdunensis, S. aureus, Streptococcus parasanguinis, Streptococcus pneumonia, and Enterococcus faecalis were resistant to vancomycin, which is considered as the last-resort antibiotic. Therefore, this study shows that most bacterial strains in human milk demonstrate mild to strong antibiotic resistance. Whether commensal bacteria in milk could serve as vehicles of antibiotic resistance should be further investigated.

  6. Surveillance of multidrug resistant uropathogenic bacteria in hospitalized patients in Indian

    PubMed Central

    Mishra, Monali Priyadarsini; Debata, Nagen Kumar; Padhy, Rabindra Nath

    2013-01-01

    Objective To record surveillance, antibiotic resistance of uropathogens of hospitalized patients over a period of 18 months. Methods Urine samples from wards and cabins were used for isolating urinary tract infection (UTI)-causing bacteria that were cultured on suitable selective media and identified by biochemical tests; and their antibiograms were ascertained by Kirby-Bauer's disc diffusion method, in each 6-month interval of the study period, using 18 antibiotics of five different classes. Results From wards and cabins, 1 245 samples were collected, from which 996 strains of bacteria belonging to 11 species were isolated, during April 2011 to September 2012. Two Gram-positive, Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis), and nine Gram-negative bacteria, Acinetobacter baumannii, Citrobacter sp., Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis, Proteus vulgaris and Pseudomonas aeruginosa were isolated. Both S. aureus and E. faecalis were vancomycin resistant, and resistant-strains of all pathogens increased in each 6-month period of study. Particularly, all Gram-negatives were resistant to nitrofurantoin and co-trimoxazole, the most preferred antibiotics of empiric therapy for UTI. Conclusions Antibiograms of 11 UTI-causing bacteria recorded in this study indicated moderately higher numbers of strains resistant to each antibiotic studied, generating the fear of precipitating fervent episodes in public health particularly with bacteria, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and S. aureus. Moreover, vancomycin resistance in strains of S. aureus and E. faecalis is a matter of concern. PMID:23620859

  7. Bacteria on housefly eggs, Musca domestica, suppress fungal growth in chicken manure through nutrient depletion or antifungal metabolites

    NASA Astrophysics Data System (ADS)

    Lam, Kevin; Thu, Kelsie; Tsang, Michelle; Moore, Margo; Gries, Gerhard

    2009-09-01

    Female houseflies, Musca domestica (Diptera: Muscidae), lay their eggs in ephemeral resources such as animal manure. Hatching larvae compete for essential nutrients with fungi that also colonize such resources. Both the well-known antagonistic relationship between bacteria and fungi and the consistent presence of the bacterium Klebsiella oxytoca on housefly eggs led us to hypothesize (1) that K. oxytoca, and possibly other bacteria on housefly eggs, help curtail the growth of fungal resource competitors and (2) that such fungi indeed adversely affect the development of housefly larvae. Bacteria washed from housefly eggs significantly reduced the growth of fungi in chicken manure. Nineteen bacterial strains and ten fungal strains were isolated from housefly eggs or chicken manure, respectively. Co-culturing each of all the possible bacterium-fungus pairs revealed that the bacteria as a group, but no single bacterium, significantly suppressed the growth of all fungal strains tested. The bacteria's adverse effect on fungi is due to resource nutrient depletion and/or the release of antifungal chemicals. Well-established fungi in resources significantly reduced the number of larval offspring that completed development to adult flies.

  8. Laurus nobilis, Zingiber officinale and Anethum graveolens Essential Oils: Composition, Antioxidant and Antibacterial Activities against Bacteria Isolated from Fish and Shellfish.

    PubMed

    Snuossi, Mejdi; Trabelsi, Najla; Ben Taleb, Sabrine; Dehmeni, Ameni; Flamini, Guido; De Feo, Vincenzo

    2016-10-22

    Several bacterial strains were isolated from wild and reared fish and shellfish. The identification of these strains showed the dominance of the Aeromonas hydrophila species in all seafood samples, followed by Staphylococcus spp., Vibrio alginolyticus, Enterobacter cloacae, Klebsiella ornithinolytica, Klebsiella oxytoca and Serratia odorifera. The isolates were studied for their ability to produce exoenzymes and biofilms. The chemical composition of the essential oils from Laurus nobilis leaves, Zingiber officinale rhizomes and Anethum graveolens aerial parts was studied by GC and GC/MS. The essential oils' antioxidant and antibacterial activities against the isolated microorganisms were studied. Low concentrations of the three essential oils were needed to inhibit the growth of the selected bacteria and the lowest MBCs values were obtained for the laurel essential oil. The selected essential oils can be used as a good natural preservative in fish food due to their antioxidant and antibacterial activities.

  9. Cleanliness scores as indicator of Klebsiella exposure in dairy cows.

    PubMed

    Munoz, M A; Bennett, G J; Ahlström, C; Griffiths, H M; Schukken, Y H; Zadoks, R N

    2008-10-01

    This study was designed to explore the relationship between cow and udder cleanliness scores and the risk of isolation of Klebsiella spp. from lower hind legs and teat ends, respectively. The distribution of Klebsiella species was compared among isolates from teat ends, legs, and cases of clinical mastitis obtained from 2 dairy farms in New York State, with 850 and 1,000 cows, respectively. Farms were visited twice approximately 4 wk apart in August and September 2007 to obtain cleanliness scores and swabs from legs and teats. Isolates of Klebsiella clinical mastitis from each farm were collected from July through October 2007. Two studies were conducted. In the first study, whole-cow cleanliness of a purposive sample of 200 lactating cows was scored using a 4-point scale, and swabs were taken from their lower hind legs. In the second study, udder cleanliness of a separate convenience sample of 199 lactating cows was scored in the milking parlor, and swabs were taken from their teat ends before and after premilking udder preparation. Prevalence of Klebsiella spp. on legs and teat ends before udder preparation was 59 and 60%, respectively. Logistic regression was used to explore the association between isolation of Klebsiella spp. and cleanliness scores. Cow cleanliness scores and udder cleanliness scores were not associated with detection of Klebsiella on legs and on teats before udder preparation, respectively. After udder preparation, 43% of previously Klebsiella positive teat end samples remained positive, with significant differences between farms and months. Teats from dirty udders were significantly more likely to test positive for Klebsiella after udder preparation than teats from clean udders. The proportion of Klebsiella pneumoniae and Klebsiella oxytoca isolates was similar for isolates from teat end swabs and clinical mastitis cases, supporting the notion that the presence of Klebsiella on teat ends may lead to opportunistic intramammary infections

  10. Macrophage migration inhibitory factor deficiency is associated with impaired killing of gram-negative bacteria by macrophages and increased susceptibility to Klebsiella pneumoniae sepsis.

    PubMed

    Roger, Thierry; Delaloye, Julie; Chanson, Anne-Laure; Giddey, Marlyse; Le Roy, Didier; Calandra, Thierry

    2013-01-15

    The cytokine macrophage migration inhibitory factor (MIF) is an important component of the early proinflammatory response of the innate immune system. However, the antimicrobial defense mechanisms mediated by MIF remain fairly mysterious. In the present study, we examined whether MIF controls bacterial uptake and clearance by professional phagocytes, using wild-type and MIF-deficient macrophages. MIF deficiency did not affect bacterial phagocytosis, but it strongly impaired the killing of gram-negative bacteria by macrophages and host defenses against gram-negative bacterial infection, as shown by increased mortality in a Klebsiella pneumonia model. Consistent with MIF's regulatory role of Toll-like 4 expression in macrophages, MIF-deficient cells stimulated with lipopolysaccharide or Escherichia coli exhibited reduced nuclear factor κB activity and tumor necrosis factor (TNF) production. Addition of recombinant MIF or TNF corrected the killing defect of MIF-deficient macrophages. Together, these data show that MIF is a key mediator of host responses against gram-negative bacteria, acting in part via a modulation of bacterial killing by macrophages.

  11. Duration of Colonization With Klebsiella pneumoniae Carbapenemase-Producing Bacteria at Long-Term Acute Care Hospitals in Chicago, Illinois

    PubMed Central

    Haverkate, Manon R.; Weiner, Shayna; Lolans, Karen; Moore, Nicholas M.; Weinstein, Robert A.; Bonten, Marc J. M.; Hayden, Mary K.; Bootsma, Martin C. J.

    2016-01-01

    Background. High prevalence of Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae has been reported in long-term acute care hospitals (LTACHs), in part because of frequent readmissions of colonized patients. Knowledge of the duration of colonization with KPC is essential to identify patients at risk of KPC colonization upon readmission and to make predictions on the effects of transmission control measures. Methods. We analyzed data on surveillance isolates that were collected at 4 LTACHs in the Chicago region during a period of bundled interventions, to simultaneously estimate the duration of colonization during an LTACH admission and between LTACH (re)admissions. A maximum-likelihood method was used, taking interval-censoring into account. Results. Eighty-three percent of patients remained colonized for at least 4 weeks, which was the median duration of LTACH stay. Between LTACH admissions, the median duration of colonization was 270 days (95% confidence interval, 91–∞). Conclusions. Only 17% of LTACH patients lost colonization with KPC within 4 weeks. Approximately half of the KPC-positive patients were still carriers when readmitted after 9 months. Infection control practices should take prolonged carriage into account to limit transmission of KPCs in LTACHs. PMID:27747253

  12. Extended-spectrum beta-lactamase-producing Klebsiella spp. in a neonatal intensive care unit: risk factors for the infection and the dynamics of the molecular epidemiology.

    PubMed

    Kristóf, K; Szabó, D; Marsh, J W; Cser, V; Janik, L; Rozgonyi, F; Nobilis, A; Nagy, K; Paterson, D L

    2007-08-01

    The extended-spectrum beta-lactamase (ESBL)-producing Klebsiella spp. cause worldwide problems in intensive care units. The aim of this study was to investigate the molecular epidemiology of ESBL-producing Klebsiella pneumoniae and K. oxytoca strains in a neonatal intensive care unit (NICU) in Budapest, Hungary and to determine the risk factors of the infections and the epidemiological features. Infections with Klebsiella spp. were analyzed retrospectively by reviewing the medical records between January 2001 and December 2005. Antibiotic susceptibility tests, isoelectric focusing, pulsed field gel electrophoresis, plasmid analysis, PCR for bla(TEM) and bla(SHV) and DNA sequencing analysis were performed on ESBL-producing Klebsiella isolates. A total of 45 babies were found to be infected with non-ESBL-producing Klebsiella spp. and 39 with ESBL-producing Klebsiella spp. Of the parameters analyzed, including sex, gestational age, twin pregnancy, birth weight, presence of central vascular catheter, mechanical ventilator use, parenteral nutrition, polymicrobial infection, caesarean section, transfusion and mortality, we found no statistically significant difference between the ESBL and the non-ESBL groups, or between the K. pneumoniae and K. oxytoca species. Further characterization of the ESBL-producing K. pneumoniae and K. oxytoca strains isolated between February 2001 and January 2003 revealed three distinct PFGE patterns of SHV-5-producing K. pneumoniae (A, B, E) and two distinct patterns of SHV-12-producing K. oxytoca (C,D) isolates; these had different plasmid profiles. From July to November 2005, a new SHV-5 producing K. oxytoca (F) was isolated. The molecular epidemiology of ESBL-producing organisms in a NICU over time shows substantial shifts in predominant strains. The ESBL production of the infected organisms has an impact on the survival of newborn babies with infections caused by Klebsiella spp.

  13. Reduction of furfural to furfuryl alcohol by ethanologenic strains of bacteria and its effect on ethanol production from xylose.

    PubMed

    Gutiérrez, Tony; Buszko, Marian L; Ingram, Lonnie O; Preston, James F

    2002-01-01

    The ethanologenic bacteria Escherichia coli strains KO11 and LYO1, and Klebsiella oxytoca strain P2, were investigated for their ability to metabolize furfural. Using high performance liquid chromatography and 13C-nuclear magnetic resonance spectroscopy, furfural was found to be completely biotransformed into furfuryl alcohol by each of the three strains with tryptone and yeast extract as sole carbon sources. This reduction appears to be constitutive with NAD(P)H acting as electron donor. Glucose was shown to be an effective source of reducing power. Succinate inhibited furfural reduction, indicating that flavins are unlikely participants in this process. Furfural at concentrations >10 mM decreased the rate of ethanol formation but did not affect the final yield. Insight into the biochemical nature of this furfural reduction process may help efforts to mitigate furfural toxicity during ethanol production by ethanologenic bacteria.

  14. Klebsiella michiganensis sp. nov., a new bacterium isolated from a tooth brush holder.

    PubMed

    Saha, Ratul; Farrance, Christine E; Verghese, Bindhu; Hong, Sunhee; Donofrio, Robert S

    2013-01-01

    Isolate W14(T) recovered from a household tooth brush holder was found to be gram-negative, a facultative anaerobic, non-motile, capsulated, and a non-endospore-forming straight rod. Based on phylogenetic analysis with 16S rRNA gene sequence, isolate W14(T) was affiliated to the genus Klebsiella. The closest phylogenetic relative was K. oxytoca with 99 % similarity in the 16S rRNA gene sequence. The major whole-cell fatty acids were C(16:0) (31.23 %), C(18:1ω6c)/C(18:1ω7c) (21.10 %), and C(16:1ω7c)/C(16:1ω6c) (19.05 %). The sequence similarities of isolate W14(T) based on rpoB, gyrA, and gyrB were 97, 98, and 98 % with K. oxytoca, and 97, 93, and 90 % with K. mobilis (=Enterobacter aerogenes), respectively. The ribotyping pattern showed a 0.46 similarity with K. oxytoca ATCC 13182(T) and 0.24 with K. mobilis ATCC 13048(T). The DNA G+C content of isolate W14(T) was 54.6 mol%. The DNA-DNA relatedness was 55.7 % with K. oxytoca ATCC 13182(T). Using the identification technology of MALDI-TOF mass spectrometry, the top matches for this isolate were K. oxytoca ATCC 13182(T) (Match Factor Score 1.998) and K. mobilis (Score 1.797). On the basis of phenotypic, biochemical, chemotaxonomic, and molecular studies, isolate W14(T) could be differentiated from other members of the genus Klebsiella including K. mobilis. Therefore, it is proposed that isolate W14(T) (=ATCC BAA-2403(T)=DSM 25444(T)) should be classified as the type strain of a novel species of the genus Klebsiella, K. michiganensis sp. nov.

  15. Molecular analysis of population structure and antibiotic resistance of Klebsiella isolates from a three-year surveillance program in Florence hospitals, Italy.

    PubMed

    Donnarumma, F; Indorato, C; Mastromei, G; Goti, E; Nicoletti, P; Pecile, P; Fanci, R; Bosi, A; Casalone, E

    2012-03-01

    We report the results of a three-year surveillance program of Klebsiella spp. in six hospitals in Florence (Italy). A total of 172 Klebsiella isolates were identified and typed by AFLP: 122 were K. pneumoniae and 50 were K. oxytoca. Most K. pneumoniae (80%) and K. oxytoca (93%) showed unrelated AFLP profiles. Beside this heterogeneous population structure, we found five small epidemic clonal groups of K. pneumoniae. Four of these groups were involved in outbreak events, three of which occurred in neonatal ICUs. The fifth clonal group spread in three different wards of two hospitals. Only one non-epidemic clonal group of K. oxytoca was detected. The frequencies of isolates with multiple antibiotic resistances increased with time; at the end of the study period, most K. pneumoniae were resistant to all the antibiotics tested. A PCR analysis of seven ertapenem resistant isolates was unable to detect any of the major genes known to underlie carbapenem resistance in K. pneumoniae.

  16. Alimentary Tract Bacteria Isolated and Identified with API-20E and Molecular Cloning Techniques from Australian Tropical Fruit Flies, Bactrocera cacuminata and B. tryoni

    PubMed Central

    Thaochan, N.; Drew, R. A. I.; Hughes, J. M.; Vijaysegaran, S.; Chinajariyawong, A.

    2010-01-01

    Bacteria were isolated from the crop and midgut of field collected Bactrocera cacuminata (Hering) and Bactrocera tryoni (Froggatt) (Diptera: Tephritidae). Two methods were used, firstly isolation onto two types of bacteriological culture media (PYEA and TSA) and identification using the API-20E diagnostic kit, and secondly, analysis of samples using the 16S rRNA gene molecular diagnostic method. Using the API-20E method, 10 genera and 17 species of bacteria in the family Enterobacteriaceae were identified from cultures growing on the nutrient agar. The dominant species in both the crop and midgut were Citrobacter freundii, Enterobacter cloacae and Klebsiella oxytoca. Providencia rettgeri, Klebsiella pneumoniae ssp ozaenae and Serratia marcescens were isolated from B. tryoni only. Using the molecular cloning technique that is based on 16S rRNA gene sequences, five bacteria classes were dignosed — Alpha-, Beta-, Gamma- and Delta- Proteobacteria and Firmicutes — including five families, Leuconostocaceae, Enterococcaceae, Acetobacteriaceae, Comamonadaceae and Enterobacteriaceae. The bacteria affiliated with Firmicutes were found mainly in the crop while the Gammaproteobacteria, especially the family Enterobacteriaceae, was dominant in the midgut. This paper presents results from the first known application of molecular cloning techniques to study bacteria within tephritid species and the first record of Firmicutes bacteria in these flies. PMID:20883132

  17. [Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents--special references to bacteria isolated between April 2010 and March 2011].

    PubMed

    Shinagawa, Nagao; Taniguchi, Masaaki; Hirata, Koichi; Furuhata, Tomohisa; Fukuhara, Kenichiro; Mizugucwi, Tohru; Osanai, Hiroyuki; Yanai, Yoshiyuki; Hata, Fumitake; Kihara, Chikasi; Sasaki, Kazuaki; Oono, Keisuke; Nakamura, Masashi; Shibuya, Hitoshi; Hasegawa, Itaru; Kimura, Masami; Watabe, Kosho; Kobayashi, Yasuhito; Yamaue, Hiroki; Hirono, Seiko; Takesue, Yoshio; Fujiwara, Toshiyoshi; Shinoura, Susumu; Kimura, Hideyuki; Hoshikawa, Tsuyoshi; Oshima, Hideki; Aikawa, Naoki; Sasaki, Junichi; Suzuki, Masaru; Sekine, Kazuhiko; Abe, Shinya; Takeyama, Hiromitsu; Wakasugi, Takehiro; Mashita, Keiji; Tanaka, Moritsugu; Mizuno, Akira; Ishikawa, Masakazu; Iwai, Akihiko; Saito, Takaaki; Muramoto, Masayuki; Kubo, Shoji; Lee, Shigeru; Fukuhara, Kenichiro; Iwagaki, Hiromi; Tokunaga, Naoyuki; Sueda, Taijliro; Hiyama, Elso; Murakami, Yoshiaki; Ohge, Hiroki; Uemura, Kenichiro; Tsumura, Hiroaki; Kanehiro, Tetsuya; Takeuchi, Hitoshi; Tanakaya, Koujn; Iwasaki, Mitsuhiro

    2014-10-01

    Bacteria isolated from surgical infections during the period from April 2010 to March 2011 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 631 strains including 25 strains of Candida spp. were isolated from 170 (81.7%) of 208 patients with surgical infections. Four hundred and twenty two strains were isolated from primary infections, and 184 strains were isolated from surgical site infection. From primary infections, anaerobic Gram-negative bacteria were predominant, followed by aerobic Gram-negative bacteria, while from surgical site infection aerobic Gram-positive bacteria were predominant, followed by anaerobic Gram-negative bacteria. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus spp. such as Enterococcus faecalis, Enterococcus faecium, and Enterococcus avium was highest, followed by Streptococcus spp. such as Streptococcus anginosus and Staphylococcus spp. such as Staphylococcus aureus, in this order, from primary infections, while Enterococcus spp. such as E. faecalis and E. faecium was highest, followed by Staphylococcus spp. such as S. aureus from surgical site infection. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, and Pseudomonas aeruginosa in this order, and from surgical site infection, E. coli and R aeruginosa were most predominantly isolated, followed by E. cloacae and K. pneumoniae. Among anaerobic Gram-positive bacteria, the isolation rates of Parvimonas micra, Eggerthella lenta, Streptococcus constellatus, Gemella morbillorum, and Collinsella aerofaciens were the highest from primary infections, and the isolation rate from surgical site infection was generally low. Among anaerobic Gram-negative bacteria, the isolation rate of Bilophila wadsworthia was the highest from primary infections, followed by, Bacteroides

  18. Characteristics of alcohol dehydrogenases of certain aerobic bacteria representing human colonic flora.

    PubMed

    Nosova, T; Jousimies-Somer, H; Kaihovaara, P; Jokelainen, K; Heine, R; Salaspuro, M

    1997-05-01

    We have recently proposed the existence of a bacteriocolonic pathway for ethanol oxidation [i.e., ethanol is oxidized by alcohol dehydrogenases (ADHs) of intestinal bacteria resulting in high intracolonic levels of reactive and toxic acetaldehyde]. The aim of this in vitro study was to characterize further ADH activity of some aerobic bacteria, representing the normal human colonic flora. These bacteria were earlier shown to possess high cytosolic ADH activities (Escherichia coli IH 133369, Klebsiella pneumoniae IH 35385, Klebsiella oxytoca IH 35339, Pseudomonas aeruginosa IH 35342, and Hafnia alvei IH 53227). ADHs of the tested bacteria strongly preferred NAD as a cofactor. Marked ADH activities were found in all bacteria, even at low ethanol concentrations (1.5 mM) that may occur in the colon due to bacterial fermentation. The Km for ethanol varied from 29.9 mM for K. pneumoniae to 0.06 mM for Hafnia alvei. The inhibition of ADH by 4-methylpyrazole was found to be of the competitive type in 4 of 5 bacteria, and Ki varied from 18.26 +/- 3.3 mM for Escherichia coli to 0.47 +/- 0.13 mM for K. pneumoniae. At pH 7.4, ADH activity was significantly lower than at pH 9.6 in four bacterial strains. ADH of K. oxytoca, however, showed almost equal activities at neutral pH and at 9.6. In conclusion, NAD-linked alcohol dehydrogenases of aerobic colonic bacteria possess low apparent Km's for ethanol. Accordingly, they may oxidize moderate amounts of ethanol ingested during social drinking with nearly maximal velocity. This may result in the marked production of intracolonic acetaldehyde. Kinetic characteristics of the bacterial enzymes may enable some of them to produce acetaldehyde even from endogenous ethanol formed by other bacteria via alcoholic fermentation. The microbial ADHs were inhibited by 4-methylpyrazole by the same competitive inhibition as hepatic ADH, however, with nearly 1000 times lower susceptibility. Individual variations in human colonic flora may thus

  19. Identification of Clinical Isolates of Indole-Positive and Indole-Negative Klebsiella spp.▿

    PubMed Central

    Alves, Maria Silvana; Dias, Rubens Clayton da Silva; de Castro, Angela Christina Dias; Riley, Lee W.; Moreira, Beatriz Meurer

    2006-01-01

    Biochemical methods employed to classify bacterial species have limitations and may have contributed to the taxonomic complexity recently reported for the genus Klebsiella. The objective of the present study was to apply a simple biochemical test panel to classify a collection of human Klebsiella isolates. We found that with only three additional tests, it is possible to place most isolates in a defined species. Analysis of a 512-bp sequence of the rpoB gene was used as the reference. A total of 16 conventional and 4 supplementary tests were used to evaluate 122 recent isolates identified as Klebsiella from 120 patients, isolated at the clinical laboratory of a university hospital in Minas Gerais, Brazil. Of these, 102 (84%) isolates were identified as Klebsiella pneumoniae or Klebsiella variicola, 19 (15%) as Klebsiella oxytoca, and 1 (1%) as Raoultella planticola. Enterobacterial repetitive intergenic consensus-PCR typing revealed a diversity of genotypes. rpoB gene sequencing confirmed the phenotypic identification and detected five K. variicola isolates among the K. pneumoniae/K. variicola group. Three additional tests that include growth at 10°C and histamine and d-melezitose assimilation should be considered essential tests for the typing of Klebsiella isolates. PMID:16928968

  20. Virulence properties of extended spectrum β-lactamase-producing Klebsiella species in meat samples.

    PubMed

    Gundogan, Neslihan; Citak, Sumru; Yalcin, Emel

    2011-04-01

    The present study was carried out to identify virulence properties (siderophores, serum resistance, and hemolysin) and antibiotic resistance in extended spectrum β-lactamase (ESBL)-producing Klebsiella isolates from 60 calf and chicken meat samples purchased from various supermarkets in Ankara, Turkey. Of the 45 Klebsiella isolates, 24 (53%) were identified as K. oxytoca and 21 (47%) were identified as K. pneumoniae. A high proportion of Klebsiella isolates had virulence factors such as hemolytic activity (67%), siderophore production (44%), and serum resistance (38%). The double-disk synergy test was used to determine ESBL production. ESBL production was detected in 13 (29%) of the 45 Klebsiella isolates. Resistance to 14 antimicrobials was tested in all Klebsiella isolates by the disk diffusion method. All isolates were resistant to two or more antimicrobial agents. All ESBL-producing Klebsiella isolates were highly resistant to cephalosporins and monobactams. Our findings indicate that meat and its products represent potential hazardous sources of multidrug-resistant and virulent Klebsiella species.

  1. Efficacy of surface disinfectant cleaners against emerging highly resistant gram-negative bacteria

    PubMed Central

    2014-01-01

    Background Worldwide, the emergence of multidrug-resistant gram-negative bacteria is a clinical problem. Surface disinfectant cleaners (SDCs) that are effective against these bacteria are needed for use in high risk areas around patients and on multi-touch surfaces. We determined the efficacy of several SDCs against clinically relevant bacterial species with and without common types of multidrug resistance. Methods Bacteria species used were ATCC strains; clinical isolates classified as antibiotic-susceptible; and multi-resistant clinical isolates from Klebsiella oxytoca, Klebsiella pneumoniae, and Serratia marcescens (all OXA-48 and KPC-2); Acinetobacter baumannii (OXA-23); Pseudomonas aeruginosa (VIM-1); and Achromobacter xylosoxidans (ATCC strain). Experiments were carried out according to EN 13727:2012 in quadruplicate under dirty conditions. The five evaluated SDCs were based on alcohol and an amphoteric substance (AAS), an oxygen-releaser (OR), surface-active substances (SAS), or surface-active-substances plus aldehydes (SASA; two formulations). Bactericidal concentrations of SDCs were determined at two different contact times. Efficacy was defined as a log10 ≥ 5 reduction in bacterial cell count. Results SDCs based on AAS, OR, and SAS were effective against all six species irrespective of the degree of multi-resistance. The SASA formulations were effective against the bacteria irrespective of degree of multi-resistance except for one of the four P. aeruginosa isolates (VIM-1). We found no general correlation between SDC efficacy and degree of antibiotic resistance. Conclusions SDCs were generally effective against gram-negative bacteria with and without multidrug resistance. SDCs are therefore suitable for surface disinfection in the immediate proximity of patients. Single bacterial isolates, however, might have reduced susceptibility to selected biocidal agents. PMID:24885029

  2. Production of 2,3-butanediol by Klebsiella oxytoca from various sugars in microalgal hydrolysate.

    PubMed

    Kim, Yong Jae; Joo, Hyun Woo; Park, Juyi; Kim, Duk-Ki; Jeong, Ki Jun; Chang, Yong Keun

    2015-01-01

    A new fermentation process using a mixed sugar medium is proposed in this study for 2,3-butanediol (2,3-BDO) production. The medium contained seven different monosugars known to be present in Nannochloropsis oceanica hydrolysate. The performance of each sugar when existing alone or together with glucose was evaluated. All the sugars except fucose were successfully metabolized for 2,3-BDO production. A 2,3-BDO yield of 0.31g/g was achieved with the mixed sugar medium, which was very close to that with the glucose-only medium. However, the 2,3-BDO productivity (0.28 g L(-1) h(-1) ) was found to be about 30% lower than that with glucose, implying, as expected, the existence of glucose repression on the uptake of other sugars. Strain development is in need to remove such negative effect of glucose for improved process efficiency. Fucose with the lowest uptake rate and no contribution to 2,3-BDO production can be a high value-added byproduct, once recovered and purified.

  3. Microbiological investigation of Raphanus sativus L. grown hydroponically in nutrient solutions contaminated with spoilage and pathogenic bacteria.

    PubMed

    Settanni, Luca; Miceli, Alessandro; Francesca, Nicola; Cruciata, Margherita; Moschetti, Giancarlo

    2013-01-01

    The survival of eight undesired (spoilage/pathogenic) food related bacteria (Citrobacter freundii PSS60, Enterobacter spp. PSS11, Escherichia coli PSS2, Klebsiella oxytoca PSS82, Serratia grimesii PSS72, Pseudomonas putida PSS21, Stenotrophomonas maltophilia PSS52 and Listeria monocytogenes ATCC 19114(T)) was investigated in mineral nutrient solution (MNS) during the crop cycle of radishes (Raphanus sativus L.) cultivated in hydroponics in a greenhouse. MNSs were microbiologically analyzed weekly by plate count. The evolution of the pure cultures was also evaluated in sterile MNS in test tubes. The inoculated trials contained an initial total mesophilic count (TMC) ranging between 6.69 and 7.78Log CFU/mL, while non-sterile and sterile control trials showed levels of 4.39 and 0.97Log CFU/mL, respectively. In general, all inoculated trials showed similar levels of TMC in MNS during the experimentation, even though the levels of the inoculated bacteria decreased. The presence of the inoculums was ascertained by randomly amplified polymorphic DNA (RAPD) analysis applied on the isolates collected at 7-day intervals. At harvest, MNSs were also analyzed by denaturing gradient gel electrophoresis (DGGE). The last analysis, except P. putida PSS21 in the corresponding trial, did not detect the other bacteria, but confirmed that pseudomonads were present in un-inoculated MNSs. Despite the high counts detected (6.44 and 7.24CFU/g), only C. freundii PSS60, Enterobacter spp. PSS11 and K. oxytoca PSS82 were detected in radishes in a living form, suggesting their internalization.

  4. The antigens contributing to the serological cross-reactions of Proteus antisera with Klebsiella representatives.

    PubMed

    Palusiak, Agata

    2015-03-01

    Proteus sp. and Klebsiella sp. mainly cause infections of the urinary and respiratory tracts or wounds in humans. The representatives of both genera produce virulence factors like lipopolysaccharide (LPS) or outer membrane proteins (OMPs) having much in common in the structures and/or functions. To check how far this similarity is revealed in the serological cross-reactivity, the bacterial masses of 24 tested Klebsiella sp. strains were tested in ELISA with polyclonal rabbit antisera specific to the representatives of 79 Proteus O serogroups. The strongest reacting systems were selected to Western blot, where the majority of Klebsiella masses reacted in a way characteristic for electrophoretic patterns of proteins. The strongest reactions were obtained for proteins of near 67 and 40 kDa and 12.5 kDa. Mass spectrometry analysis of the proteins samples of one Proteus sp. and one Klebsiella sp. strain showed the GroEL like protein of a sequence GI number 2980926 to be similar for both strains. In Western blot some Klebsiella sp. masses reacted similarly to the homologous Proteus LPSs. The LPS contribution in the observed reactions of the high molecular-mass LPS species was confirmed for Klebsiella oxytoca 0.062.

  5. Molecular Characteristics and Antibiotic Resistance Profiles of Klebsiella Isolates in Mthatha, Eastern Cape Province, South Africa

    PubMed Central

    Obi, Larry; Morobe, Isaac; Bisi-Johnson, Mary

    2017-01-01

    The increase in the incidence of extended-spectrum β-lactamase- (ESBL-) producing Klebsiella species has become a serious problem worldwide, because of their incrimination in antibiotic resistance. The objective of this study is to investigate the resistance genes responsible for ESBL-producing Klebsiella species and carbapenemase-producing Klebsiella (CRE) isolated in Mthatha and to study their epidemiology. A prospective, descriptive study of 202 nonrepetitive samples from patients was obtained from Nelson Mandela Academic Hospital. The cultured Klebsiella isolates were subjected to antimicrobial susceptibility tests and the polymerase chain reaction of blaCTX-M, blaTEM, blaSHV, blaKPC, and blaNDM genes. Overall K. pneumoniae were the majority with 169 (83.7%) species isolates, followed by K. oxytoca with 29 (14.4%), while K. ozaenae and Raoultella ornithinolytica were 2 (0.9%) each. The prevalence of ESBL production in all Klebsiella species was 117 (57.9%). ESBL-genotypic resistance is driven in Mthatha by blaSHV 121 (77.1%) followed by blaTEM 105 (66.9%) and blaCTX-M at 89 (56.7%). The most common ESBL genotype combination among the Klebsiella was blaTEM + blaSHV + blaCTX-M at 79 (50.3%). There is a steady increase in the rate of ESBL genes in the last five years. PMID:28250772

  6. Characterization of extended-spectrum β-lactamase (ESBL)-producing Klebsiella, Enterobacter, and Citrobacter obtained in environmental samples of a Tunisian hospital.

    PubMed

    Dziri, Raoudha; Klibi, Naouel; Alonso, Carla Andrea; Said, Leila Ben; Bellaaj, Ridha; Slama, Karim Ben; Boudabous, Abdellatif; Torres, Carmen

    2016-10-01

    The assessment of the hospital environment as a reservoir of ESBL-producing Enterobacteriaceae in Tunisian hospitals is scarcely analyzed, except for Escherichia coli. The aim of this study was to evaluate the presence of ESBL-producing non-E. coli Enterobacteriaceae (ESBL-EbNoEc) in 300 samples of abiotic surfaces and the hands of patients and staff of a Tunisian Hospital, and to characterize the ESBL genes of the recovered isolates. ESBL-EbNoEc were recovered in 28 of 300 (9.3%) analyzed samples and were identified as Klebsiella pneumoniae (n= 11), Enterobacter cloacae (n=11), Citrobacter freundii (n=4) and Klebsiella oxytoca (n=2). The bla genes identified by PCR and sequencing among the strains were as follows: 11 K.pneumoniae strains [blaCTX-M-15+ blaTEM-1+ blaSHV-11 (n=6); blaCTX-M-15+ blaTEM-1+ blaSHV-28 (n=3); blaCTX-M-15+ blaTEM-1+ blaSHV-1 (n=2)], 11 E. cloacae strains [blaCTX-M-15 (n=6); blaCTX-M-15+ blaTEM-1b (n=2); blaCTX-M-15+ blaTEM-1b+ blaOXA-1 (n=1);blaCTX-M-15+ blaOXA-1 (n=1);blaSHV-12 (n=1)], 4 C. freundii strains [blaCTX-M-15] and 2 K. oxytoca strains [blaCTX-M-15 (n=1); blaSHV-12 (n=1)]. The ISEcp1 and orf477 sequences were identified upstream and downstream of the blaCTX-M-15 gene, respectively, in 3 K. pneumoniae and 3 E. cloacae isolates. The PFGE analysis demonstrated three unrelated pulsotypes in K. pneumoniae strains and five pulsotypes in E. cloacae. The uncontrolled dissemination of ESBL-producing bacteria, even in the hospital environment, has become a real problem and new strategies and hygienic rules are needed to stop this bacterial dissemination.

  7. Potential virulence of Klebsiella sp. isolates from enteral diets

    PubMed Central

    Pereira, S.C.L.; Vanetti, M.C.D.

    2015-01-01

    We aimed to evaluate the potential virulence of Klebsiella isolates from enteral diets in hospitals, to support nosocomial infection control measures, especially among critical-care patients. Phenotypic determination of virulence factors, such as capsular expression on the external membrane, production of aerobactin siderophore, synthesis of capsular polysaccharide, hemolytic and phospholipase activity, and resistance to antibiotics, which are used therapeutically, were investigated in strains of Klebsiella pneumoniae and K. oxytoca. Modular industrialized enteral diets (30 samples) as used in two public hospitals were analyzed, and Klebsiella isolates were obtained from six (20%) of them. The hypermucoviscous phenotype was observed in one of the K. pneumoniae isolates (6.7%). Capsular serotypes K1 to K6 were present, namely K5 and K4. Under the conditions of this study, no aerobactin production, hemolytic activity or lecithinase activity was observed in the isolates. All isolates were resistant to amoxicillin and ampicillin and sensitive to cefetamet, imipenem, chloramphenicol, gentamicin and sulfamethoxazole-trimethoprim. Most K. pneumoniae isolates (6/7, 85.7%) from hospital B presented with a higher frequency of resistance to the antibiotics tested in this study, and multiple resistance to at least four antibiotics (3/8; 37.5%) compared with isolates from Hospital A. The variations observed in the antibiotic resistance profiles allowed us to classify the Klebsiella isolates as eight antibiotypes. No production of broad-spectrum β-lactamases was observed among the isolates. Our data favor the hypothesis that Klebsiella isolates from enteral diets are potential pathogens for nosocomial infections. PMID:26176307

  8. Nickel-Resistant Bacteria from Anthropogenically Nickel-Polluted and Naturally Nickel-Percolated Ecosystems

    PubMed Central

    Stoppel, R.; Schlegel, H. G.

    1995-01-01

    DNA fragments harboring the nickel resistance determinants from bacteria isolated from anthropogenically polluted ecosystems in Europe and Zaire were compared with those harboring the nickel resistance determinants from bacteria isolated from naturally nickel-percolated soils from New Caledonia by DNA-DNA hybridization. The biotinylated DNA probes were derived from the previously described Alcaligenes eutrophus CH34, Alcaligenes xylosoxidans 31A, Alcaligenes denitrificans 4a-2, and Klebsiella oxytoca CCUG 15788 and four new nickel resistance-determining fragments cloned from strains isolated from soils under nickel-hyperaccumulating trees. Nine probes were hybridized with endonuclease-cleaved plasmid and total DNA samples from 56 nickel-resistant strains. Some of the New Caledonian strains were tentatively identified as Acinetobacter, Pseudomonas mendocina, Comamonas, Hafnia alvei, Burkholderia, Arthrobacter aurescens, and Arthrobacter ramosus strains. The DNA of most strains showed homologies to one or several of the following nickel resistance determinants: the cnr and ncc operons of the strains A. eutrophus CH34 and A. xylosoxidans 31A, respectively, the nre operon of strain 31A, and the nickel resistance determinants of K. oxytoca. On the basis of their hybridization reactions the nickel resistance determinants of the strains could be assigned to four groups: (i) cnr/ncc type, (ii) cnr/ncc/nre type, (iii) K. oxytoca type, and (iv) others. The majority of the strains were assigned to the known groups. Among the strains from Belgium and Zaire, exclusively the cnr/ncc and the cnr/ncc/nre types were found. Among the New Caledonian strains all four types were represented. Homologies to the nre operon were found only in combination with the cnr/ncc operon. The homologies to the cnr/ncc operon were the most abundant and were detected alone or together with homologies to the nre operon. Only the DNA of the strains isolated from soil in Scotland and the United States

  9. Klebsiella pneumoniae survives within macrophages by avoiding delivery to lysosomes.

    PubMed

    Cano, Victoria; March, Catalina; Insua, Jose Luis; Aguiló, Nacho; Llobet, Enrique; Moranta, David; Regueiro, Verónica; Brennan, Gerard P; Millán-Lou, Maria Isabel; Martín, Carlos; Garmendia, Junkal; Bengoechea, José A

    2015-11-01

    Klebsiella pneumoniae is an important cause of community-acquired and nosocomial pneumonia. Evidence indicates that Klebsiella might be able to persist intracellularly within a vacuolar compartment. This study was designed to investigate the interaction between Klebsiella and macrophages. Engulfment of K. pneumoniae was dependent on host cytoskeleton, cell plasma membrane lipid rafts and the activation of phosphoinositide 3-kinase (PI3K). Microscopy studies revealed that K. pneumoniae resides within a vacuolar compartment, the Klebsiella-containing vacuole (KCV), which traffics within vacuoles associated with the endocytic pathway. In contrast to UV-killed bacteria, the majority of live bacteria did not co-localize with markers of the lysosomal compartment. Our data suggest that K. pneumoniae triggers a programmed cell death in macrophages displaying features of apoptosis. Our efforts to identify the mechanism(s) whereby K. pneumoniae prevents the fusion of the lysosomes to the KCV uncovered the central role of the PI3K-Akt-Rab14 axis to control the phagosome maturation. Our data revealed that the capsule is dispensable for Klebsiella intracellular survival if bacteria were not opsonized. Furthermore, the environment found by Klebsiella within the KCV triggered the down-regulation of the expression of cps. Altogether, this study proves evidence that K. pneumoniae survives killing by macrophages by manipulating phagosome maturation that may contribute to Klebsiella pathogenesis.

  10. Effects of some metallic compounds on Klebsiella

    SciTech Connect

    Wong, S.H.

    1988-04-01

    Many industrial and waste disposal practices unconsciously pollute the environment by adding excess heavy metals to it. Although reports show an inconsistency in the toxic levels of heavy metals such as zinc, nickel, cadmium, mercury and silvery between microbial groups, the toxic effects of the metals on microorganisms have been well documented. Little is known of the differential effects these metals have on coliform K. pneumoniae and K. oxytoca. These bacteria are widely recognized as antibiotic resistant opportunistic pathogens. Besides, they are able to fix dinitrogen. In this study, these metals were found to affect these organisms in a variety of concentrations. Such effect could affect the total coliform count in water, dinitrogen fixation, and removable of nitrate in soil and water.

  11. Effects of some metallic compounds on Klebsiella

    SciTech Connect

    Wong, S.H. )

    1988-05-01

    Many industrial and waste disposal practices unconsciously pollute the environment by adding excess heavy metals to it. Although reports show an inconsistency in the toxic levels of heavy metals such as zinc, nickel, cadmium, mercury and silver between microbial groups, the toxic effects of the metals on microorganisms have been well documented. Little is known of the differential effects these metals have on coliform K. pneumoniae and K. oxytoca. These bacteria are widely recognized as antibiotic resistant opportunistic pathogens ubiquitously distributed in environments. Besides, they are able to fix dinitrogen. In this study, these metals were found to affect these organisms in a variety of concentrations. Such effect could affect the total coliform count in water, dinitrogen fixation, and removable of nitrate in soil and water.

  12. [Post-marketing surveillance of antibacterial activities of cefozopran against various clinical isolates--II. Gram-negative bacteria].

    PubMed

    Igari, Jun; Oguri, Toyoko; Hiramatsu, Nobuyoshi; Akiyama, Kazumitsu; Koyama, Tsuneo

    2002-02-01

    As a post-marketing surveillance, the in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates were yearly evaluated and compared with those of other cephems, oxacephems, penicillins, monobactams, and carbapenems. Changes in CZOP susceptibility for the bacteria were also evaluated with the bacterial resistance ratio calculated with the breakpoint MIC. Twenty-five species (3,362 strains) of Gram-negative bacteria were isolated from the clinical materials annually collected from 1996 to 2000, and consisted of Moraxella (Branhamella) catarrhalis (n = 136), Haemophilus influenzae (n = 289), Escherichia coli (n = 276), Klebsiella pneumoniae (n = 192), Klebsiella oxytoca (n = 157), Enterobacter cloacae (n = 189), Enterobacter aerogenes (n = 93), Serratia marcescens (n = 172), Serratia liquefaciens (n = 24), Citrobacter freundii (n = 177), Citrobacter koseri (n = 70), Proteus mirabilis (n = 113), Proteus vulgaris (n = 89), Morganella morganii (n = 116), Providencia spp. (n = 41), Pseudomonas aeruginosa (n = 290), Pseudomonas fluorescens (n = 56), Pseudomonas putida (n = 63), Acinetobacter baumannii (n = 146), Acinetobacter lwoffii (n = 34), Burkholderia cepacia (n = 101), Stenotrophomonas maltophilia (n = 169), Bacteroides fragilis group (n = 196), and Prevotella/Porphyromonas (n = 173). An antibacterial activity of CZOP against E. coli, K. pneumoniae, K. oxytoca, and S. marcescens was potent and consistent with or more preferable than the study results obtained until the new drug application approval. MIC90 of CZOP against M.(B.) catarrhalis, C. koseri, and P. aeruginosa was not considerably changed and consistent with the study results obtained until the new drug application approval. MIC90 of CZOP against E. cloacae, E. aerogenes, and P. mirabilis increased year by year. The increase in MIC90 of CZOP against E. aerogenes and P. mirabilis, however, was not considered to be an obvious decline in susceptibility. In

  13. Susceptibility to levofloxacin of clinical isolates of bacteria from intensive care and haematology/oncology patients in Switzerland: a multicentre study.

    PubMed

    Siegrist, H H; Nepa, M C; Jacquet, A

    1999-06-01

    The objective of this study was to examine the susceptibility of clinical isolates to levofloxacin, a fluoroquinolone with extended activity against Gram-positive bacteria, and other antibiotics in 12 Swiss clinical microbiology laboratories using the NCCLS disc diffusion technique. Isolates were prospectively collected from intensive care units (ICUs (59%), oncology wards (7%) and other units with haematology/oncology patients (34%) from June 1995 to March 1996. The levofloxacin breakpoints used were as recommended by the manufacturer. A total of 310 Gram-positive and 580 Gram-negative isolates from the respiratory tract (36%), skin/wounds (12%), blood (16%), urine (17%) and other sources (19%) were tested. The percentage of isolates susceptible to levofloxacin was 100% for Enterococcus spp. (38 strains), Streptococcus agalactiae (13), Streptococcus pneumoniae (65), Acinetobacter spp. (11), Citrobacter diversus (6), Citrobacter freundii (17), Klebsiella oxytoca (39), Morganella morganii (16), Proteus mirabilis (20), Proteus vulgaris (23), Serratia spp. (19), Stenotrophomonas maltophilia (10) and Haemophilus influenzae (41). The percentage of isolates susceptible to levofloxacin for Staphylococcus aureus (95 strains, including 2% MRSA) was 94%, coagulase-negative staphylococci (85) 65%, Enterobacter spp. (75) 99%, Escherichia coli (111) 97%, Klebsiella pneumoniae (45) 98% and Pseudomonas aeruginosa (124) 87%. In conclusion, levofloxacin is a new fluoroquinolone to which the most common clinical isolates in Switzerland are susceptible. The susceptibility of Enterococcus spp. and S. pneumoniae to levofloxacin was particularly remarkable. This compound appears to be a promising therapeutic alternative for the treatment of Gram-positive infections.

  14. Indole-3-acetic acid (IAA) production in symbiotic and non-symbiotic nitrogen-fixing bacteria and its optimization by Taguchi design.

    PubMed

    Shokri, Dariush; Emtiazi, Giti

    2010-09-01

    Production of Indole-3-acetic acid (IAA) in 35 different symbiotic and non-symbiotic nitrogen-fixing bacteria strains isolated from soil and plant roots was studied and assayed by chromatography and colorimetric methods. These bacteria included Agrobacterium, Paenibacillus, Rhizobium, Klebsiella oxytoca, and Azotobacter. The best general medium and synergism effects of isolates for IAA production were investigated. Effects of different variables containing physical parameters and key media components and optimization of condition for IAA production were performed using the Design of Experiments. Qualitek-4 (W32b) software for automatic design and analysis of the experiments, both based on Taguchi method was used. The results showed that Rhizobium strains, symbiotic, and Paenibacillus non-symbiotic bacteria yielded the highest concentrations of IAA (in the range of 5.23-0.27 and 4.90-0.19 ppm IAA/mg biomass, respectively) and IAA production was increased by synergism effect of them. Yeast Extract Mannitol medium supplemented with L-tryptophan was the best general medium for IAA production. The analysis of experimental data using Taguchi method indicated that nitrogen source is very prominent variable in affecting the yield and mannitol as carbon source, potassium nitrate (1%), and L-tryptophan (3 g/l) as nitrogen sources after 72-h incubation at 30 degrees C were the optimum conditions for production of IAA. 5.89 ppm IAA/mg biomass was produced under these optimal conditions.

  15. Isolation and characterization of multidrug-resistant Klebsiella spp. isolated from shrimp imported from Thailand.

    PubMed

    Nawaz, Mohamed; Khan, S A; Tran, Q; Sung, K; Khan, A A; Adamu, I; Steele, R S

    2012-04-16

    A study was undertaken to isolate and characterize tetracycline and nalidixic acid-resistant Klebsiella spp. in farm-raised, imported shrimp sold in the United States. Sixty-seven multiple antibiotic-resistant Klebsiella spp. strains were isolated from imported shrimp samples. Using morphological and biochemical methods, fifty-three strains were tentatively identified as Klebsiella pneumoniae and fourteen as K. oxytoca. Although all isolates were resistant to tetracycline, only 8 were resistant to nalidixic acid. These 8 isolates were further screened by PCR for quinolone resistance genes (qnrA, B, S, gyrA, B and parC). PCR protocols failed to amplify any qnr genes. The purified PCR amplicons of gyrA, gyrB and parC were sequenced and analyzed for point mutations that confer resistance to fluoroquinolone antibiotics. Analysis of the sequences of the gyrA amplicons from nalidixic acid-resistant Klebsiella spp. indicated two point mutations in gyrA at positions 83 (Ser→Phe) and 87 (Asp→Ala). Sequence analysis of the parC amplicons indicated an amino acid change at position 80 (Ser→Ile). No mutations were detected in gyrB. Template DNA from all isolates was screened for tetracycline resistance genes (tetA-E). Oligonucleotide primers specifically targeting a 305-bp region of tetB and a 477-bp region of tetD successfully amplified sequences from 91.0 and 44.0% of the isolates, respectively. None of the isolates contained tetA, tetC or tetE genes. Plasmids (2.0-16.0kb) were found in 23 of the 67 isolates. XbaI-PFGE identified 32 distinct macro restriction patterns (mrps) among the 61 multiple drug-resistant Klebsiella spp. that were typable. Our results indicate that imported shrimp is a reservoir for multidrug resistant Klebsiella spp. and potential health risks posed by such strains should not be underestimated.

  16. Kinetics of Colonization of Adult Queensland Fruit Flies (Bactrocera tryoni) by Dinitrogen-Fixing Alimentary Tract Bacteria.

    PubMed

    Murphy, K M; Teakle, D S; Macrae, I C

    1994-07-01

    The average total population of bacteria remained constant in the alimentary tracts of adult laboratory-raised Queensland fruit flies (Bactrocera tryoni) although the insects had ingested large numbers of live bacteria as part of their diet. The mean number of bacteria (about 13 million) present in the gut of the insects from 12 to 55 days after emergence was not significantly modified when, at 5 days after emergence, the flies were fed antibiotic-resistant bacteria belonging to two species commonly isolated from the gut of field-collected B. tryoni. Flies were fed one marked dinitrogen-fixing strain each of either Klebsiella oxytoca or Enterobacter cloacae, and the gastrointestinal tracts of fed flies were shown to be colonized within 7 days by antibiotic-resistant isolates of K. oxytoca but not E. cloacae. The composition of the microbial population also appeared to be stable in that the distribution and frequency of bacterial taxa among individual flies exhibited similar patterns whether or not the flies had been bacteria fed. Isolates of either E. cloacae or K. oxytoca, constituting 70% of the total numbers, were usually dominant, with oxidative species including pseudomonads forming the balance of the population. Antibiotic-resistant bacteria could be spread from one cage of flies to the adjacent surfaces of a second cage within a few days and had reached a control group several meters distant by 3 weeks. Restriction of marked bacteria to the population of one in five flies sampled from the control group over the next 30 days suggested that the bacterial population in the gut of the insect was susceptible to alteration in the first week after emergence but that thereafter it entered a steady state and was less likely to be perturbed by the introduction of newly encountered strains. All populations sampled, including controls, included at least one isolate of the dinitrogen-fixing family Enterobacteriaceae; many were distinct from the marked strains fed to the

  17. In vitro activity of gemifloxacin against recent clinical isolates of bacteria in Korea.

    PubMed Central

    Yong, Dong Eun; Cheong, Hee-Jin; Kim, Yang Soo; Park, Yeon Joon; Kim, Woo-Joo; Woo, Jun Hee; Lee, Kyung Won; Kang, Moon Won; Choo, Youn-Sung

    2002-01-01

    Gemifloxacin is an enhanced-affinity fluoroquinolone with broad-spectrum antibacterial activity. In Korea, resistant bacteria are relatively more prevalent than in other industrialized countries. In this study, we studied the in vitro activities of gemifloxacin, gatifloxacin, moxifloxacin, levofloxacin, ciprofloxacin, and other commonly used antimicrobial agents against 1,689 bacterial strains isolated at four Korean university hospitals during 1999-2000. Minimum inhibitory concentrations (MICs) were determined using the agar dilution method of National Committee for Clinical Laboratory Standards. Gemifloxacin had the lowest MICs for the respiratory pathogens: 90% of Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae were inhibited by 0.06, 0.03, and 0.03 mg/L, respectively. Gemifloxacin was more active than the other fluoroquinolones against methicillin-susceptible Staphylococcus aureus, coagulase-negative staphylococci, streptococci, and Enterococcus faecalis. The MIC90s of gemifloxacin for Klebsiella oxytoca, Proteus vulgaris, and non-typhoidal Salmonella spp. were 0.25, 1.0, and 0.12 mg/L, respectively, while those for other Gram-negative bacilli were 4-64 mg/L. In conclusion, gemifloxacin was the most active among the comparative agents against Gram-positive species, including respiratory pathogens isolated in Korea. PMID:12482994

  18. Osteopontin promotes host defense during Klebsiella pneumoniae-induced pneumonia.

    PubMed

    van der Windt, G J W; Hoogerwerf, J J; de Vos, A F; Florquin, S; van der Poll, T

    2010-12-01

    Klebsiella pneumoniae is a common cause of nosocomial pneumonia. Osteopontin (OPN) is a phosphorylated glycoprotein involved in inflammatory processes, some of which is mediated by CD44. The aim of this study was to determine the role of OPN during K. pneumoniae-induced pneumonia. Wild-type (WT) and OPN knockout (KO) mice were intranasally infected with 10⁴ colony forming units of K. pneumoniae, or administered Klebsiella lipopolysaccharides (LPS). In addition, recombinant OPN (rOPN) was intranasally administered to WT and CD44 KO mice. During Klebsiella pneumonia, WT mice displayed elevated pulmonary and plasma OPN levels. OPN KO and WT mice showed similar pulmonary bacterial loads 6 h after infection; thereafter, Klebsiella loads were higher in lungs of OPN KO mice and the mortality rate in this group was higher than in WT mice. Early neutrophil recruitment into the bronchoalveolar space was impaired in the absence of OPN after intrapulmonary delivery of either Klebsiella bacteria or Klebsiella LPS. Moreover, rOPN induced neutrophil migration into the bronchoalveolar space, independent from CD44. In vitro, OPN did not affect K. pneumoniae growth or neutrophil function. In conclusion, OPN levels were rapidly increased in the bronchoalveolar space during K. pneumoniae pneumonia, where OPN serves a chemotactic function towards neutrophils, thereby facilitating an effective innate immune response.

  19. Effect of Algae and Plant Lectins on Planktonic Growth and Biofilm Formation in Clinically Relevant Bacteria and Yeasts

    PubMed Central

    Vasconcelos, Mayron Alves; Arruda, Francisco Vassiliepe Sousa; Carneiro, Victor Alves; Silva, Helton Colares; Nascimento, Kyria Santiago; Sampaio, Alexandre Holanda; Cavada, Benildo; Teixeira, Edson Holanda; Henriques, Mariana

    2014-01-01

    This study aimed to evaluate the abilities of plant and algae lectins to inhibit planktonic growth and biofilm formation in bacteria and yeasts. Initially, ten lectins were tested on Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella oxytoca, Pseudomonas aeruginosa, Candida albicans, and C. tropicalis at concentrations of 31.25 to 250 μg/mL. The lectins from Cratylia floribunda (CFL), Vatairea macrocarpa (VML), Bauhinia bauhinioides (BBL), Bryothamnion seaforthii (BSL), and Hypnea musciformis (HML) showed activities against at least one microorganism. Biofilm formation in the presence of the lectins was also evaluated; after 24 h of incubation with the lectins, the biofilms were analyzed by quantifying the biomass (by crystal violet staining) and by enumerating the viable cells (colony-forming units). The lectins reduced the biofilm biomass and/or the number of viable cells to differing degrees depending on the microorganism tested, demonstrating the different characteristics of the lectins. These findings indicate that the lectins tested in this study may be natural alternative antimicrobial agents; however, further studies are required to better elucidate the functional use of these proteins. PMID:24982871

  20. Sulfoquinovose degraded by pure cultures of bacteria with release of C3-organosulfonates: complete degradation in two-member communities.

    PubMed

    Denger, Karin; Huhn, Thomas; Hollemeyer, Klaus; Schleheck, David; Cook, Alasdair M

    2012-03-01

    Sulfoquinovose (SQ, 6-deoxy-6-sulfoglucose) was synthesized chemically. An HPLC-ELSD method to separate SQ and other chromophore-free sulfonates, e.g. 2,3-dihydroxypropane-1-sulfonate (DHPS), was developed. A set of 10 genome-sequenced, sulfonate-utilizing bacteria did not utilize SQ, but an isolate, Pseudomonas putida SQ1, from an enrichment culture did so. The molar growth yield with SQ was half of that with glucose, and 1 mol 3-sulfolactate (mol SQ)(-1) was formed during growth. The 3-sulfolactate was degraded by the addition of Paracoccus pantotrophus NKNCYSA, and the sulfonate sulfur was recovered quantitatively as sulfate. Another isolate, Klebsiella oxytoca TauN1, could utilize SQ, forming 1 mol DHPS (mol SQ)(-1) ; the molar growth yield with SQ was half of that with glucose. This DHPS could be degraded by Cupriavidus pinatubonensis JMP134, with quantitative recovery of the sulfonate sulfur as sulfate. We presume that SQ can be degraded by communities in the environment.

  1. Rapid identification of gram-negative bacteria with and without CTX-M extended-spectrum β-lactamase from positive blood culture bottles by PCR followed by microchip gel electrophoresis.

    PubMed

    Fujita, Shin-ichi; Yosizaki, Kentaro; Ogushi, Thikako; Uechi, Kouhei; Takemori, Yukiko; Senda, Yasuko

    2011-04-01

    We evaluated the usefulness of PCR analysis of the 16S-23S rRNA gene internal transcribed spacer (ITS) and the CTX-M extended-spectrum β-lactamase (ESBL) followed by microchip gel electrophoresis (MGE) for direct identification and CTX-M detection of Gram-negative bacteria (GNB) from positive blood culture bottles. Of 251 GNB isolated from blood cultures containing a single bacterium, 225 (90%) were correctly identified at the species level directly from positive blood culture bottles by comparing the ITS-PCR patterns of the sample strain with those of the control strains. There were no cases of incorrect identification. Limitations encountered included the inability to detect mixed cultures (four bottles) as well as some species (Enterobacter species and Klebsiella oxytoca) demonstrating identical ITS-PCR patterns. A total of 109 ESBL-producing isolates from various clinical materials obtained between January 2005 and December 2008 were examined for bla(CTX-M), bla(SHV), and bla(TEM) genes by PCR and sequences of PCR products. CTX-M ESBL was detected in 105 isolates, and SHV ESBL was detected in two isolates. The remaining two isolates (K. oxytoca) were shown to harbor bla(OXY.) Twenty (19%) of 104 Escherichia coli isolates from blood cultures were suspected to produce ESBL by the combination disk method, and these isolates were shown to harbor CTX-M ESBL by PCR-MGE. The results were obtained within 1.5 h at a calculated cost of $6.50 per specimen. In conclusion, simultaneous detection of ITS length polymorphisms and bla(CTX)-(M) by single PCR followed by MGE is useful for rapid, cost-effective, and reliable species-level identification of CTX-M ESBL-producing GNB responsible for bloodstream infections.

  2. [Spreading and mechanisms of antibiotic resistance of microorganisms, producing beta-lactamases. Molecular mechanisms of resistance to beta-lactams of Klebsiella spp. strains, isolated in cases of nosocomial infections].

    PubMed

    Ivanov, D V; Egorov, A M

    2008-01-01

    Antibiotic sensivity of nosocomial Klebsiella spp. strains (n = 212), isolated from patients treated in 30 medical centers of 15 various regions of Russia was investigated. The Klebsiella genus was represented by the following species: Klebsiella pneumoniae ss. pneumoniae--182 (85.8%), Klebsiella pneumoniae ss. ozaenae--1 (0.5%), Klebsiella oxytoca--29 (13.7%) isolates. The most active antibacterial agents against the investigated strains were carbapenems (imipenem and meropenem). Among 3rd generation cephalosporine the lowest MICs were observed for ceftazidime/clavulanic acid (MIC50--0.25 microg/ml, MIC90--64 microg/ml) and cefoperazone/sulbactam (MIC50--16 microg/ml, MIC90--64 microg/ml). Beta-lactamase genes (TEM, SHV, CTX) were detected in 42 Klebsiella pneumoniae ss. pneumoniae strains by PCR. Alone or in various combinations TEM type beta-lactamases have been found in 16 (38.1%) isolates, SHV--in 29 (69%), and CTX--in 27 (64.3%). Combinations of 2 different determinants were detected in 23.8% of the isolates, 3--in 26.2%. There were not isolates producing MBL class B among resistant to carbapenems nosocomial Klebsiella spp. strains.

  3. A one-step multiplex PCR to identify Klebsiella pneumoniae, Klebsiella variicola, and Klebsiella quasipneumoniae in the clinical routine.

    PubMed

    Fonseca, Erica Lourenço; Ramos, Nilceia da Veiga; Andrade, Bruno G Nascimento; Morais, Lena L C S; Marin, Michel F Abanto; Vicente, Ana Carolina P

    2017-04-01

    Klebsiella pneumoniae, Klebsiella variicola and Klebsiella quasipneumoniae are difficult to differentiate phenotypically, leading to misinterpretation of their infection prevalence. We propose a multiplex PCR for blaSHV, blaLEN and blaOKP and their flanking gene (deoR). Since this scheme focuses only on chromosomal genes, it will be feasible for Klebsiella identification in the clinical routine.

  4. Studies on water quality and pathogenic bacteria in coastal water Langkawi, Malaysia.

    PubMed

    Jalal, K C A; Faizul, H N Noor; Naim, M Azrul; John, B Akbar; Kamaruzzaman, B Y

    2012-07-01

    A study on physico-chemical parameters and pathogenic bacterial community was carried out at the coastal waters of Pulau Tuba island, Langkawi. The physico-chemical parameters such as temperature (27.43-28.88 degrees C), dissolved oxygen (3.79-6.49 mg l(-1)), pH (7.72-8.20), salinity (33.10-33.96 ppt), total dissolved solids (32.27-32.77 g l(-1)) and specific conductivity (49.83-51.63 mS cm(-1)) were observed. Station 3 and station 4 showed highest amount of nitrates (26.93 and 14.61 microg at N l(-1)) than station 1 (2.04 microg at N l(-1)) and station 2 (4.18 microg at N l(-1)). The highest concentration (12.4 +/- microg l(-1)) of chlorophyll a was observed in station 4 in October 2005. High phosphorus content (561 microg P l(-1)) was found in the station 2. Thirteen bacterial isolates were successfully identified using API 20E system. The highest amount of bacteria was observed at Station 4 (3400 CFU ml(-1)) and the lowest numberwas at Station 2 (890 CFU ml(-1)). Out of identified 13 Gram-negative bacterial isolates dominant species were Aeromonas hydrophila, Klebsiella oxytoca, Pseudomonas baumannii, Vibrio vulnificus, Proteus mirabilis, Providencia alcalifaciens and Serratia liquefaciens. Apart from this, oil biodegrading Pseudomonas putida were also identified. The study reveals the existing status of water quality is still conducive and the reasonably diverse with Gram-negative bacteria along the Pulau Tuba Langkawi.

  5. Occurrence of yeasts, enterococci and other enteric bacteria in subgingival biofilm of HIV-positive patients with chronic gingivitis and necrotizing periodontitis.

    PubMed

    Gaetti-Jardim Júnior, Elerson; Nakano, Viviane; Wahasugui, Thais C; Cabral, Fátima C; Gamba, Rosa; Avila-Campos, Mario Julio

    2008-04-01

    The purpose of this study was to determine the prevalence of enteric bacteria and yeasts in biofilm of 80 HIV-positive patients with plaque-associated gingivitis or necrotizing periodontitis. Patients were subjected to extra, intra oral and radiographic examinations. The oral hygiene, bleeding on probing, gingival conditions, and attachment loss were evaluated. Clinical specimens were collected from gingival crevices or periodontal pockets, transferred to VMGA III, diluted and transferred to Sabouraud Dextrose agar with 100 μg/ml of chloramphenicol, peptone water, EVA broth, EMB agar, SS agar, Bile esculin agar and Brilliant green agar. Isolation of yeasts was carried out at room temperature, for 3-7 days; and for the isolation of enteric microorganisms plates were incubated at 37°C, for 24-48 h. The yeasts identification was performed according to the carbon and nitrogen assimilation, fermentation of carbohydrates and germ tube formation. Bacteria were identified according to their colonial and cellular morphologies and biochemical tests. Yeasts were identified as Candida albicans and its occurrence was more common in patients with CD4+ below 200/mm(3) and was affected by the extension of periodontal involvement (P = 0.0345). Enteric bacteria recovered from clinical specimens were identified as Enterobacter sakazakii, Enterobacter cloacae, Serratia liquefaciens, Klebsiella oxytoca and Enterococcus sp. Enterobacteriaceae and enterococci were detected in 32.5% of clinical samples from patients with necrotizing periodontitis. In conclusion, non-oral pathogenic bacteria and C. albicans were more prevalent in periodontal sites of HIV-positive patients with necrotizing periodontitis and chronic gingivitis.

  6. Occurrence of yeasts, enterococci and other enteric bacteria in subgingival biofilm of HIV-positive patients with chronic gingivitis and necrotizing periodontitis

    PubMed Central

    Gaetti-Jardim Júnior, Elerson; Nakano, Viviane; Wahasugui, Thais C.; Cabral, Fátima C.; Gamba, Rosa; Avila-Campos, Mario Julio

    2008-01-01

    The purpose of this study was to determine the prevalence of enteric bacteria and yeasts in biofilm of 80 HIV-positive patients with plaque-associated gingivitis or necrotizing periodontitis. Patients were subjected to extra, intra oral and radiographic examinations. The oral hygiene, bleeding on probing, gingival conditions, and attachment loss were evaluated. Clinical specimens were collected from gingival crevices or periodontal pockets, transferred to VMGA III, diluted and transferred to Sabouraud Dextrose agar with 100 μg/ml of chloramphenicol, peptone water, EVA broth, EMB agar, SS agar, Bile esculin agar and Brilliant green agar. Isolation of yeasts was carried out at room temperature, for 3-7 days; and for the isolation of enteric microorganisms plates were incubated at 37°C, for 24-48 h. The yeasts identification was performed according to the carbon and nitrogen assimilation, fermentation of carbohydrates and germ tube formation. Bacteria were identified according to their colonial and cellular morphologies and biochemical tests. Yeasts were identified as Candida albicans and its occurrence was more common in patients with CD4+ below 200/mm3 and was affected by the extension of periodontal involvement (P = 0.0345). Enteric bacteria recovered from clinical specimens were identified as Enterobacter sakazakii, Enterobacter cloacae, Serratia liquefaciens, Klebsiella oxytoca and Enterococcus sp. Enterobacteriaceae and enterococci were detected in 32.5% of clinical samples from patients with necrotizing periodontitis. In conclusion, non-oral pathogenic bacteria and C. albicans were more prevalent in periodontal sites of HIV-positive patients with necrotizing periodontitis and chronic gingivitis. PMID:24031212

  7. Genetic organization of transposase regions surrounding blaKPC carbapenemase genes on plasmids from Klebsiella strains isolated in a New York City hospital.

    PubMed

    Gootz, Thomas D; Lescoe, Mary Kay; Dib-Hajj, Fadia; Dougherty, Brian A; He, Wen; Della-Latta, Phyllis; Huard, Richard C

    2009-05-01

    Carbapenem-resistant Klebsiella strains carrying Klebsiella pneumoniae carbapenemases (KPC) are endemic to New York City and are spreading across the United States and internationally. Recent studies have indicated that the KPC structural gene is located on a 10-kb plasmid-borne element designated Tn4401. Fourteen Klebsiella pneumoniae strains and one Klebsiella oxytoca strain isolated at a New York City hospital in 2005 carrying either bla(KPC-2) or bla(KPC-3) were examined for isoforms of Tn4401. Ten of the Klebsiella strains contained a 100-bp deletion in Tn4401, corresponding to the Tn4401a isoform. The presence of this deletion adjacent to the upstream promoter region of bla(KPC) in Tn4401a resulted in a different -35 promoter sequence of TGGAGA than that of CTGATT present in isoform Tn4401b. Complete sequencing of one plasmid carrying bla(KPC) from each of three nonclonal isolates indicated the presence of genes encoding other types of antibiotic resistance determinants. The 70.6-kb plasmid from K. pneumoniae strain S9 carrying bla(KPC-2) revealed two identical copies of Tn4401b inserted in an inverse fashion, but in this case, one of the elements disrupted a group II self-splicing intron. In K. pneumoniae strain S15, the Tn4401a element carrying bla(KPC-2) was found on both a large 120-kb plasmid and a smaller 24-kb plasmid. Pulsed-field gel electrophoresis results indicate that the isolates studied represent a heterogeneous group composed of unrelated as well as closely related Klebsiella strains. Our results suggest that endemic KPC-positive Klebsiella strains constitute a generally nonclonal population comprised of various alleles of bla(KPC) on several distinct plasmid genetic backgrounds. This study increases our understanding of the genetic composition of the evolving and expanding role of KPC-producing, healthcare-associated, gram-negative pathogens.

  8. Klebsiella phages representing a novel clade of viruses with an unknown DNA modification and biotechnologically interesting enzymes.

    PubMed

    Maciejewska, Barbara; Roszniowski, Bartosz; Espaillat, Akbar; Kęsik-Szeloch, Agata; Majkowska-Skrobek, Grazyna; Kropinski, Andrew M; Briers, Yves; Cava, Felipe; Lavigne, Rob; Drulis-Kawa, Zuzanna

    2017-01-01

    Lytic bacteriophages and phage-encoded endolysins (peptidoglycan hydrolases) provide a source for the development of novel antimicrobial strategies. In the present study, we focus on the closely related (96 % DNA sequence identity) environmental myoviruses vB_KpnM_KP15 (KP15) and vB_KpnM_KP27 (KP27) infecting multidrug-resistant Klebsiella pneumoniae and Klebsiella oxytoca strains. Their genome organisation and evolutionary relationship are compared to Enterobacter phage phiEap-3 and Klebsiella phages Matisse and Miro. Due to the shared and distinct evolutionary history of these phages, we propose to create a new phage genus "Kp15virus" within the Tevenvirinae subfamily. In silico genome analysis reveals two unique putative homing endonucleases of KP27 phage, probably involved in unrevealed mechanism of DNA modification and resistance to restriction digestion, resulting in a broader host spectrum. Additionally, we identified in KP15 and KP27 a complete set of lysis genes, containing holin, antiholin, spanin and endolysin. By turbidimetric assays on permeabilized Gram-negative strains, we verified the ability of the KP27 endolysin to destroy the bacterial peptidoglycan. We confirmed high stability, absence of toxicity on a human epithelial cell line and the enzymatic specificity of endolysin, which was found to possess endopeptidase activity, cleaving the peptide stem between L-alanine and D-glutamic acid.

  9. Population dynamics of bacteria associated with different strains of the pine wood nematode Bursaphelenchus xylophilus after inoculation in maritime pine (Pinus pinaster).

    PubMed

    Roriz, Mariana; Santos, Carla; Vasconcelos, Marta W

    2011-08-01

    , Klebsiella, Paenibacillus, Pantoea and Terribacillus genera were identified. General bacterial diversity increased with the progression of the disease. Bacillus spp. were predominant at the earlier stage of disease progression and Klebsiella oxytoca at the later stages. Furthermore, bacterial species isolated from the surface of nematodes were similar to those isolated from the xylem of pines. In the present work new bacterial species were identified which have never been reported before in this type of study and may be associated with their geographical origin (Portugal). P. pinaster, the pine species used in this study, was different from those commonly grown in Japan and China. Furthermore, it was the first time that bacteria were isolated and identified from an avirulent pine wood nematode isolate.

  10. [Post-marketing surveillance of antibacterial activities of cefozopran against various clinical isolates--II. Gram-negative bacteria].

    PubMed

    Igari, Jun; Oguri, Toyoko; Hiramatsu, Nobuyoshi; Akiyama, Kazumitsu; Koyama, Tsuneo

    2003-10-01

    As a post-marketing surveillance, the in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates were yearly evaluated and compared with those of other cephems, oxacephems, carbapenems, monobactams, and penicillins. Changes in CZOP susceptibility among bacteria were also evaluated with the bacterial resistance ratio calculated from the breakpoint MIC. Twenty-five species (4,154 strains) of Gram-negative bacteria were isolated from the clinical materials annually collected from 1996 to 2001, and consisted of Moraxella (Branhamella) catarrhalis, Haemophilus influenzae, Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, Enterobacter aerogenes, Serratia marcescens, Serratia liquefaciens, Citrobacter freundii, Citrobacter koseri, Proteus mirabilis, Proteus vulgaris, Morganella morganii, Providencia spp., Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas putida, Acinetobacter baumannii, Acinetobacter Iwoffii, Burkholderia cepacia, Stenotrophomonas maltophilia, Bacteroides fragilis group, and Prevotella/Porphyromonas. CZOP preserved its antibacterial activity against M. (B.) catarrhalis (MIC90: 4 micrograms/mL) and showed comparable activity to carbapenems against H. influenzae (MIC90: 1 microgram/mL). The antibacterial activity of CZOP against E. coli was preferable (MIC90: 0.125 microgram/mL) and comparable to those of cefpirome (CPR), cefepime (CFPM), and imipenem (IPM). The MIC90 of CZOP against K. pneumoniae and K. oxytoca was 1 and 0.25 microgram/mL, respectively. The MIC90 of CZOP against E. cloacae increased during 6 years (32 to 128 micrograms/mL). The antibacterial activity of CZOP against E. aerogenes was preferable (MIC90: 1 microgram/mL). The antibacterial activities of CZOP against S. marcescens and S. liquefaciens were relatively potent (MIC90: 0.5 and 0.25 microgram/mL) and comparable to those of CPR, CFPM, and carumonam. CZOP preserved comparable antibacterial

  11. Molecular characterization of antimicrobial resistance in Gram-negative bacteria isolated from bovine mastitis in Egypt.

    PubMed

    Ahmed, Ashraf M; Shimamoto, Tadashi

    2011-05-01

    The aim of this study was to characterize the genetic basis of multidrug resistance in Gram-negative bacteria isolated from bovine mastitis cases in Egypt. Multidrug resistance phenotypes were found in 34 of 112 (30.4%) Gram-negative bacterial isolates, which harbored at least one antimicrobial resistance gene. The most prevalent multidrug-resistant (MDR) species were Enterobacter cloacae (8 isolates, 7.1%), Klebsiella pneumoniae (7 isolates, 6.3%), Klebsiella oxytoca (7 isolates, 6.3%), Escherichia coli (5 isolates, 4.5%), and Citrobacter freundii (3 isolates, 2.7%). The most commonly observed resistance phenotypes were against ampicillin (97.0%), streptomycin (94.1%), tetracycline (91.2%), trimethoprim-sulfamethoxazole (88.2%), nalidixic acid (85.3%), and chloramphenicol (76.5%). Class 1 integrons were detected in 28 (25.0%) isolates. The gene cassettes within class 1 integrons included those encoding resistance to trimethoprim (dfrA1, dfrA5, dfrA7, dfrA12, dfrA15, dfrA17, and dfrA25), aminoglycosides (aadA1, aadA2, aadA5, aadA7, aadA12, aadA22, and aac(3)-Id), chloramphenicol (cmlA), erythromycin (ereA2), and rifampicin (arr-3). Class 2 integrons were identified in 6 isolates (5.4%) with three different profiles. Furthermore, the β-lactamase encoding genes, bla(TEM), bla(SHV), bla(CTX-M), and bla(OXA), the plasmid-mediated quinolone resistance genes, qnr and aac(6)-Ib-cr, and the florfenicol resistance gene, floR, were also identified. To the best of our knowledge, the results identified class 2 integrons, qnr and aac(6)-Ib-cr from cases of mastitis for the first time. This is the first report of molecular characterization for antimicrobial resistance in Gram-negative bacteria isolated from bovine mastitis in Africa.

  12. Deciphering tissue-induced Klebsiella pneumoniae lipid A structure.

    PubMed

    Llobet, Enrique; Martínez-Moliner, Verónica; Moranta, David; Dahlström, Käthe M; Regueiro, Verónica; Tomás, Anna; Cano, Victoria; Pérez-Gutiérrez, Camino; Frank, Christian G; Fernández-Carrasco, Helena; Insua, José Luis; Salminen, Tiina A; Garmendia, Junkal; Bengoechea, José A

    2015-11-17

    The outcome of an infection depends on host recognition of the pathogen, hence leading to the activation of signaling pathways controlling defense responses. A long-held belief is that the modification of the lipid A moiety of the lipopolysaccharide could help Gram-negative pathogens to evade innate immunity. However, direct evidence that this happens in vivo is lacking. Here we report the lipid A expressed in the tissues of infected mice by the human pathogen Klebsiella pneumoniae. Our findings demonstrate that Klebsiella remodels its lipid A in a tissue-dependent manner. Lipid A species found in the lungs are consistent with a 2-hydroxyacyl-modified lipid A dependent on the PhoPQ-regulated oxygenase LpxO. The in vivo lipid A pattern is lost in minimally passaged bacteria isolated from the tissues. LpxO-dependent modification reduces the activation of inflammatory responses and mediates resistance to antimicrobial peptides. An lpxO mutant is attenuated in vivo thereby highlighting the importance of this lipid A modification in Klebsiella infection biology. Colistin, one of the last options to treat multidrug-resistant Klebsiella infections, triggers the in vivo lipid A pattern. Moreover, colistin-resistant isolates already express the in vivo lipid A pattern. In these isolates, LpxO-dependent lipid A modification mediates resistance to colistin. Deciphering the lipid A expressed in vivo opens the possibility of designing novel therapeutics targeting the enzymes responsible for the in vivo lipid A pattern.

  13. Deciphering tissue-induced Klebsiella pneumoniae lipid A structure

    PubMed Central

    Llobet, Enrique; Martínez-Moliner, Verónica; Moranta, David; Dahlström, Käthe M.; Regueiro, Verónica; Tomás, Anna; Cano, Victoria; Pérez-Gutiérrez, Camino; Frank, Christian G.; Fernández-Carrasco, Helena; Insua, José Luis; Salminen, Tiina A.; Garmendia, Junkal; Bengoechea, José A.

    2015-01-01

    The outcome of an infection depends on host recognition of the pathogen, hence leading to the activation of signaling pathways controlling defense responses. A long-held belief is that the modification of the lipid A moiety of the lipopolysaccharide could help Gram-negative pathogens to evade innate immunity. However, direct evidence that this happens in vivo is lacking. Here we report the lipid A expressed in the tissues of infected mice by the human pathogen Klebsiella pneumoniae. Our findings demonstrate that Klebsiella remodels its lipid A in a tissue-dependent manner. Lipid A species found in the lungs are consistent with a 2-hydroxyacyl-modified lipid A dependent on the PhoPQ-regulated oxygenase LpxO. The in vivo lipid A pattern is lost in minimally passaged bacteria isolated from the tissues. LpxO-dependent modification reduces the activation of inflammatory responses and mediates resistance to antimicrobial peptides. An lpxO mutant is attenuated in vivo thereby highlighting the importance of this lipid A modification in Klebsiella infection biology. Colistin, one of the last options to treat multidrug-resistant Klebsiella infections, triggers the in vivo lipid A pattern. Moreover, colistin-resistant isolates already express the in vivo lipid A pattern. In these isolates, LpxO-dependent lipid A modification mediates resistance to colistin. Deciphering the lipid A expressed in vivo opens the possibility of designing novel therapeutics targeting the enzymes responsible for the in vivo lipid A pattern. PMID:26578797

  14. Prevalence and Antimicrobial Susceptibility Patterns of Bacteria from Milkmen and Cows with Clinical Mastitis in and around Kampala, Uganda

    PubMed Central

    Kateete, David Patrick; Kabugo, Usuf; Baluku, Hannington; Nyakarahuka, Luke; Kyobe, Samuel; Okee, Moses; Najjuka, Christine Florence; Joloba, Moses Lutaakome

    2013-01-01

    Background Identification of pathogens associated with bovine mastitis is helpful in treatment and management decisions. However, such data from sub-Saharan Africa is scarce. Here we describe the distribution and antimicrobial susceptibility patterns of bacteria from cows with clinical mastitis in Kampala, Uganda. Due to high concern of zoonotic infections, isolates from milkmen are also described. Methodology/Principal Findings Ninety seven milk samples from cows with clinical mastitis and 31 nasal swabs from milkmen were collected (one sample per cow/human). Fifty eight (60%) Gram-positive isolates namely Staphylococci (21), Enterococci (16), Streptococci (13), Lactococci (5), Micrococci (2) and Arcanobacteria (1) were detected in cows; only one grew Staphylococcus aureus. Furthermore, 24 (25%) coliforms namely Escherichia coli (12), Klebsiella oxytoca (5), Proteus vulgaris (2), Serratia (2), Citrobacter (1), Cedecea (1) and Leclercia (1) were identified. From humans, 24 Gram-positive bacteria grew, of which 11 were Staphylococci (35%) including four Staphylococcus aureus. Upon susceptibility testing, methicillin-resistant coagulase-negative staphylococci (CoNS) were prevalent; 57%, 12/21 in cows and 64%, 7/11 in humans. However, methicillin-resistant Staphylococcus aureus was not detected. Furthermore, methicillin and vancomycin resistant CoNS were detected in cows (Staphylococcus hominis, Staphylococcus lugdunensis) and humans (Staphylococcus scuiri). Also, vancomycin and daptomycin resistant Enterococci (Enterococcus faecalis and Enterococcus faecium, respectively) were detected in cows. Coliforms were less resistant with three pan-susceptible isolates. However, multidrug resistant Klebsiella, Proteus, Serratia, Cedecea, and Citrobacter were detected. Lastly, similar species grew from human and bovine samples but on genotyping, the isolates were found to be different. Interestingly, human and bovine Staphylococcus aureus were genetically similar (spa-CC435

  15. Ethanol from lignocellulosic wastes with utilization of recombinant bacteria.

    PubMed

    Katzen, R; Fowler, D E

    1994-01-01

    Klebsiella oxytoca bacterium. Included is a facility providing for in-house production of cellulase enzyme, as an active whole broth for direct use in simultaneous saccharification and fermentation (SSF) of the remaining cellulose and residual 5-carbon sugars to ethanol. This is followed by distillation and dehydration in the advanced commercially available low-energy recovery system. 3. Another potential application of this unique technology involves utilization of a variety of wastes from several pulp and paper mills in close proximity, permitting collection of these wastes at low cost and reducing the considerable cost encountered in disposing of such low-energy wet waste.(ABSTRACT TRUNCATED AT 400 WORDS)

  16. Characterization of Extended-Host-Range Pseudo-T-Even Bacteriophage Kpp95 Isolated on Klebsiella pneumoniae▿

    PubMed Central

    Wu, Lii-Tzu; Chang, Shu-Ying; Yen, Ming-Ren; Yang, Tsuey-Ching; Tseng, Yi-Hsiung

    2007-01-01

    Kpp95, isolated on Klebsiella pneumoniae, is a bacteriophage with the morphology of T4-type phages and is capable of rapid lysis of host cells. Its double-stranded genomic DNA (ca. 175 kb, estimated by pulsed-field gel electrophoresis) can be cut only by restriction endonucleases with a cleavage site flanked either by A and T or by T, as tested, suggesting that it contains the modified derivative(s) of G and/or C. Over 26 protein bands were visualized upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the virion proteins. N-terminal sequencing indicated that the most abundant band (46 kDa) is the major coat protein (gp23) which has been cleaved from a signal peptide likely with a length similar to that of T4. Phylogenetic analyses based on the sequences of the central region (263 amino acid residues) of gp23 and the full length of gp18 and gp19 placed Kpp95 among the pseudo-T-even subgroup, most closely related to the coliphage JS98. In addition to being able to lyse many extended-spectrum β-lactamase strains of K. pneumoniae, Kpp95 can lyse Klebsiella oxytoca, Enterobacter agglomerans, and Serratia marcescens cells. Thus, Kpp95 deserves further studies for development as a component of a therapeutic cocktail, owing to its high efficiencies of host lysis plus extended host range. PMID:17337566

  17. Thermotolerant non-fecal source Klebsiella pneumoniae: validity of the fecal coliform test in recreational waters.

    PubMed Central

    Caplenas, N R; Kanarek, M S

    1984-01-01

    Wisconsin pulp and paper mill processing plants were evaluated for fecal coliform and total Klebsiella (i.e., thermotolerant and thermointolerant) bacterial concentrations. Using the standard fecal coliform test, up to 90 per cent of non-fecal source thermotolerant K. pneumoniae was falsely identified as fecal source bacteria. Since there is a lack of specificity in the currently used standard for fecal coliform evaluation, a more reliable health risk assessment for fecal coliform bacteria is recommended. PMID:6388365

  18. Comparative analysis of CRISPR-Cas systems in Klebsiella genomes.

    PubMed

    Shen, Juntao; Lv, Li; Wang, Xudong; Xiu, Zhilong; Chen, Guoqiang

    2017-02-03

    Prokaryotic CRISPR-Cas system provides adaptive immunity against invasive genetic elements. Bacteria of the genus Klebsiella are important nosocomial opportunistic pathogens. However, information of CRISPR-Cas system in Klebsiella remains largely unknown. Here, we analyzed the CRISPR-Cas systems of 68 complete genomes of Klebsiella representing four species. All the elements for CRISPR-Cas system (cas genes, repeats, leader sequences, and PAMs) were characterized. Besides the typical Type I-E and I-F CRISPR-Cas systems, a new Subtype I system located in the ABC transport system-glyoxalase region was found. The conservation of the new subtype CRISPR system between different species showed new evidence for CRISPR horizontal transfer. CRISPR polymorphism was strongly correlated both with species and multilocus sequence types. Some results indicated the function of adaptive immunity: most spacers (112 of 124) matched to prophages and plasmids and no matching housekeeping genes; new spacer acquisition was observed within the same sequence type (ST) and same clonal complex; the identical spacers were observed only in the ancient position (far from the leader) between different STs and clonal complexes. Interestingly, a high ratio of self-targeting spacers (7.5%, 31 of 416) was found in CRISPR-bearing Klebsiella pneumoniae (61%, 11 of 18). In some strains, there even were multiple full matching self-targeting spacers. Some self-targeting spacers were conserved even between different STs. These results indicated that some unknown mechanisms existed to compromise the function of self-targets of CRISPR-Cas systems in K. pneumoniae.

  19. Outbreak of Klebsiella pneumoniae Carbapenemase-2-Producing K. pneumoniae Sequence Type 11 in Taiwan in 2011

    PubMed Central

    Lee, Chun-Ming; Liao, Chun-Hsing; Lee, Wen-Sen; Liu, Yung-Ching; Hsueh, Po-Ren

    2012-01-01

    From June to September 2011, a total of 305 ertapenem-nonsusceptible Enterobacteriaceae isolates (MICs of ertapenem ≥ 1 μg/ml) were collected from 11 hospitals in different parts of Taiwan. The MICs of 12 antimicrobial agents against these isolates were determined using the broth microdilution method, and genes for carbapenemases were detected using PCR. Genotypes of isolates possessing carbapenemase genes were identified by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. The ertapenem-nonsusceptible Enterobacteriaceae isolates included Klebsiella pneumoniae (n = 219), Escherichia coli (n = 64), Enterobacter cloacae (n = 15), and other species (n = 7). Seven (2.3%) of the ertapenem-nonsusceptible Enterobacteriaceae isolates exhibited colistin MICs of >4 μg/ml, and 24 (7.9%) were not susceptible to tigecycline (MICs > 2 μg/ml). A total of 29 (9.5%) isolates carried genes encoding carbapenemases, namely, K. pneumoniae carbapenemase-2 (KPC-2) in 16 (7.3%) isolates of K. pneumoniae (KPC-2-KP) and IMP-8 in 5 (2.3%) isolates of K. pneumoniae, 5 (33.3%) isolates of E. cloacae, 1 isolate of E. coli, 1 isolate of Klebsiella oxytoca, and one isolate of Citrobacter freundii. The 16 KPC-2-KP isolates were isolated from patients at four different hospitals in northern Taiwan. All 16 of the KPC-2-KP isolates were susceptible to amikacin and colistin and had a similar pulsotype (pulsotype 1) and the same sequence type (sequence type 11). Infections due to KPC-2-KP mainly occurred in severely ill patients in the intensive care unit (n = 14, 88%). Four patients with infections due to KPC-2-KP died within 14 days of hospitalization. The findings are the first to demonstrate intrahospital and interhospital dissemination of KPC-2-KP in northern Taiwan. PMID:22802253

  20. Enterobacter and Klebsiella species isolated from fresh vegetables marketed in Valencia (Spain) and their clinically relevant resistances to chemotherapeutic agents.

    PubMed

    Falomir, María Pilar; Rico, Hortensia; Gozalbo, Daniel

    2013-12-01

    Occurrence of antibiotic-resistant pathogenic or commensal enterobacteria in marketed agricultural foodstuffs may contribute to their incorporation into the food chain and constitutes an additional food safety concern. In this work, we have determined the clinically relevant resistances to 11 common chemotherapeutic agents in Enterobacter and Klebsiella isolates from fresh vegetables from various sources (supermarkets and greengrocers' shops in Valencia, Spain). A total of 96 isolates were obtained from 160 vegetables analyzed (50% positive samples): 68 Enterobacter isolates (59 E. cloacae, two E. aerogenes, two E. cancerogenus, one E. gergoviae, and four E. sakazakii, currently Cronobacter spp.), and 28 Klebsiella isolates (19 K. oxytoca and 9 K. pneumoniae). Only seven isolates were susceptible to all agents tested, and no resistances to ceftazidime, ciprofloxacin, gentamicin, and chloramphenicol were detected. Most isolates were resistant to amoxicillin/clavulanic acid (74 [58 Enterobacter and 16 Klebsiella]) or to ampicillin (80 [55/25]). Other resistances were less frequent: nitrofurantoin (13 isolates [12/1]), tetracycline (6 [5/1]), co-trimoxazole (3 [3/0]), cefotaxime (1 [1/0]), and streptomycin (2 [1/1]). Multiresistant isolates to two (56 [41/15]), three (10 E. cloacae isolates), four (one E. cloacae and one K. pneumoniae isolate), and five (two E. cloacae isolates) chemotherapeutic agents were also detected. The presence of potential pathogens points to marketed fresh produce, which often is eaten raw, as a risk factor for consumer health. In addition, these results support the usefulness of these bacterial species as indicators of the spreading of antibiotic resistances into the environment, particularly in the food chain, and suggest their role as carriers of resistance determinants from farms to consumers, which may constitute an additional "silent" food safety concern. Therefore, there is a need to improve the hygienic quality of marketed fresh

  1. In-vivo study of the nuclear quadrupole interaction of99Mo (β- 99)Tc in nitrogenase of Klebsiella pneumoniaein nitrogenase of Klebsiella pneumoniae

    NASA Astrophysics Data System (ADS)

    Mottner, P.; Lerf, A.; Ni, X.; Butz, T.; Erfkamp, J.; Müller, A.

    1990-08-01

    We report on the first TDPAC-measurements of the nuclear quadrupole interaction (NQI) of (NQI) of99Mo(β-)99Tc in the nitrogenase of the bacteria Klebsiella pneumoniae. Because nitrogenase is the only Mo-containing enzyme in Klebsiella pneumoniae under the chosen conditions, no further isolation of this enzyme was necessary. The majority of the incorporated99Mo is subjected to a well defined NQI with ω=365(7) Mrad/s, η=1 and a reorientational correlation time of τcoττ≈10nsec and is attributed to the active site of the FeMo cofactor. During sample preparation we noted a pronounced affinity of the bacteria to99mTc.

  2. Enhancement of electricity production in a mediatorless air-cathode microbial fuel cell using Klebsiella sp. IR21.

    PubMed

    Lee, Yun-Yeong; Kim, Tae Gwan; Cho, Kyung-Suk

    2016-06-01

    A novel dissimilatory iron-reducing bacteria, Klebsiella sp. IR21, was isolated from the anode biofilm of an MFC reactor. Klebsiella sp. IR21 reduced 27.8 % of ferric iron to ferrous iron demonstrating that Klebsiella sp. IR21 has electron transfer ability. Additionally, Klebsiella sp. IR21 generated electricity forming a biofilm on the anode surface. When a pure culture of Klebsiella sp. IR21 was supplied into a single chamber, air-cathode MFC fed with a mixture of glucose and acetate (500 mg L(-1) COD), 40-60 mV of voltage (17-26 mA m(-2) of current density) was produced. Klebsiella sp. IR21 was also utilized as a biocatalyst to improve the electrical performance of a conventional MFC reactor. A single chamber, air-cathode MFC was fed with reject wastewater (10,000 mg L(-1) COD) from a H2 fermentation reactor. The average voltage, current density, and power density were 142.9 ± 25.74 mV, 60.5 ± 11.61 mA m(-2), and 8.9 ± 3.65 mW m(-2), respectively, in the MFC without inoculation of Klebsiella sp. IR21. However, these electrical performances of the MFC were significantly increased to 204.7 ± 40.24 mV, 87.5 ± 17.20 mA m(-2), and 18.6 ± 7.23 mW m(-2), respectively, with inoculation of Klebsiella sp. IR21. The results indicate that Klebsiella sp. IR21 can be utilized as a biocatalyst for enhancement of electrical performance in MFC systems.

  3. Methionine-to-Cysteine Recycling in Klebsiella aerogenes

    PubMed Central

    Seiflein, Thomas A.; Lawrence, Jeffrey G.

    2001-01-01

    In the enteric bacteria Escherichia coli and Salmonella enterica, sulfate is reduced to sulfide and assimilated into the amino acid cysteine; in turn, cysteine provides the sulfur atom for other sulfur-bearing molecules in the cell, including methionine. These organisms cannot use methionine as a sole source of sulfur. Here we report that this constraint is not shared by many other enteric bacteria, which can use either cysteine or methionine as the sole source of sulfur. The enteric bacterium Klebsiella aerogenes appears to use at least two pathways to allow the reduced sulfur of methionine to be recycled into cysteine. In addition, the ability to recycle methionine on solid media, where cys mutants cannot use methionine as a sulfur source, appears to be different from that in liquid media, where they can. One pathway likely uses a cystathionine intermediate to convert homocysteine to cysteine and is induced under conditions of sulfur starvation, which is likely sensed by low levels of the sulfate reduction intermediate adenosine-5′-phosphosulfate. The CysB regulatory proteins appear to control activation of this pathway. A second pathway may use a methanesulfonate intermediate to convert methionine-derived methanethiol to sulfite. While the transsulfurylation pathway may be directed to recovery of methionine, the methanethiol pathway likely represents a general salvage mechanism for recovery of alkane sulfide and alkane sulfonates. Therefore, the relatively distinct biosyntheses of cysteine and methionine in E. coli and Salmonella appear to be more intertwined in Klebsiella. PMID:11114934

  4. Klebsiella pneumoniae inoculants for enhancing plant growth

    DOEpatents

    Triplett, Eric W.; Kaeppler, Shawn M.; Chelius, Marisa K.

    2008-07-01

    A biological inoculant for enhancing the growth of plants is disclosed. The inoculant includes the bacterial strains Herbaspirillum seropedicae 2A, Pantoea agglomerans P101, Pantoea agglomerans P102, Klebsiella pneumoniae 342, Klebsiella pneumoniae zmvsy, Herbaspirillum seropedicae Z152, Gluconacetobacter diazotrophicus PA15, with or without a carrier. The inoculant also includes strains of the bacterium Pantoea agglomerans and K. pneumoniae which are able to enhance the growth of cereal grasses. Also disclosed are the novel bacterial strains Herbaspirillum seropedicae 2A, Pantoea agglomerans P101 and P102, and Klebsiella pneumoniae 342 and zmvsy.

  5. Stability Analysis in a Model of 1,2-dichloroethane Biodegradation by Klebsiella Oxytoca va 8391Immobilized on Granulated Activated Carbon

    NASA Astrophysics Data System (ADS)

    Borisov, M.; Dimitrova, N.

    2011-11-01

    We consider an ecological model for biodegradation of toxic substances in aquatic and atmospheric biotic systems. The model, which is described by a nonlinear system of four ordinary differential equations, is known to be experimentally validated. We compute the equilibrium points of the model and study their asymptotic stability. The Maple package BifTools is used to calculate one- and two-parameter bifurcations of the equilibrium points.

  6. Two-center collaborative evaluation of performance of the BD phoenix automated microbiology system for identification and antimicrobial susceptibility testing of gram-negative bacteria.

    PubMed

    Menozzi, Maria Grazia; Eigner, Ulrich; Covan, Silvia; Rossi, Sabina; Somenzi, Pietro; Dettori, Giuseppe; Chezzi, Carlo; Fahr, Anne-Marie

    2006-11-01

    The performance of the BD Phoenix Automated Microbiology System (BD Diagnostic Systems, Sparks, MD) was assessed for identification (ID) and antimicrobial susceptibility testing (AST) of the majority of clinically encountered bacterial isolates in a European collaborative two-center trial. A total of 494 bacterial isolates including various species of the Enterobacteriaceae and 110 nonfermentative gram-negative bacteria were investigated: of these, 385 were single patient isolates, and 109 were challenge strains tested at one center. The performance of the Phoenix extended-spectrum beta-lactamase (ESBL) test was also evaluated for 203 strains of Escherichia coli, Klebsiella pneumoniae, and Klebsiella oxytoca included in the study. Forty-two antimicrobial drugs were tested, including members of the following drug classes: aminoglycosides, beta-lactam antibiotics, beta-lactam/beta-lactamase inhibitors, carbapenems, cephems, monobactams, folate antagonists, quinolones, and others. Phoenix system ID results were compared to those of the laboratories' routine ID systems (API 20E and API CHE, ATB ID32E, ID32GN, and VITEK 2 [bioMérieux, Marcy l'Etoile, France]); Phoenix AST results were compared to those of frozen standard broth microdilution (SBM) panels according to NCCLS (now CLSI) guidelines (NCCLS document M100-S9, approved standard M7-A4). Discrepant results were repeated in duplicate. Concordant IDs of 98.4 and 99.1% were observed for the Enterobacteriaceae and the nonfermentative group, respectively. For AST results, the overall essential agreement was 94.2%; the category agreement was 97.3%; and the very major error rate, major error rate, and minor error rate were 1.6, 0.6, and 1.9%, respectively. In terms of ESBL detection, Phoenix results were 98.5% concordant with those of the reference system, with 98.0% sensitivity and 98.7% specificity. In conclusion, the Phoenix ID results showed high agreement with results of the systems to which they were being

  7. Evaluation of an Automated Rapid Diagnostic Assay for Detection of Gram-Negative Bacteria and Their Drug-Resistance Genes in Positive Blood Cultures

    PubMed Central

    Tojo, Masayoshi; Fujita, Takahiro; Ainoda, Yusuke; Nagamatsu, Maki; Hayakawa, Kayoko; Mezaki, Kazuhisa; Sakurai, Aki; Masui, Yoshinori; Yazaki, Hirohisa; Takahashi, Hiroshi; Miyoshi-Akiyama, Tohru; Totsuka, Kyoichi; Kirikae, Teruo; Ohmagari, Norio

    2014-01-01

    We evaluated the performance of the Verigene Gram-Negative Blood Culture Nucleic Acid Test (BC-GN; Nanosphere, Northbrook, IL, USA), an automated multiplex assay for rapid identification of positive blood cultures caused by 9 Gram-negative bacteria (GNB) and for detection of 9 genes associated with β-lactam resistance. The BC-GN assay can be performed directly from positive blood cultures with 5 minutes of hands-on and 2 hours of run time per sample. A total of 397 GNB positive blood cultures were analyzed using the BC-GN assay. Of the 397 samples, 295 were simulated samples prepared by inoculating GNB into blood culture bottles, and the remaining were clinical samples from 102 patients with positive blood cultures. Aliquots of the positive blood cultures were tested by the BC-GN assay. The results of bacterial identification between the BC-GN assay and standard laboratory methods were as follows: Acinetobacter spp. (39 isolates for the BC-GN assay/39 for the standard methods), Citrobacter spp. (7/7), Escherichia coli (87/87), Klebsiella oxytoca (13/13), and Proteus spp. (11/11); Enterobacter spp. (29/30); Klebsiella pneumoniae (62/72); Pseudomonas aeruginosa (124/125); and Serratia marcescens (18/21); respectively. From the 102 clinical samples, 104 bacterial species were identified with the BC-GN assay, whereas 110 were identified with the standard methods. The BC-GN assay also detected all β-lactam resistance genes tested (233 genes), including 54 blaCTX-M, 119 blaIMP, 8 blaKPC, 16 blaNDM, 24 blaOXA-23, 1 blaOXA-24/40, 1 blaOXA-48, 4 blaOXA-58, and 6 blaVIM. The data shows that the BC-GN assay provides rapid detection of GNB and β-lactam resistance genes in positive blood cultures and has the potential to contributing to optimal patient management by earlier detection of major antimicrobial resistance genes. PMID:24705449

  8. Evaluation of an automated rapid diagnostic assay for detection of Gram-negative bacteria and their drug-resistance genes in positive blood cultures.

    PubMed

    Tojo, Masayoshi; Fujita, Takahiro; Ainoda, Yusuke; Nagamatsu, Maki; Hayakawa, Kayoko; Mezaki, Kazuhisa; Sakurai, Aki; Masui, Yoshinori; Yazaki, Hirohisa; Takahashi, Hiroshi; Miyoshi-Akiyama, Tohru; Totsuka, Kyoichi; Kirikae, Teruo; Ohmagari, Norio

    2014-01-01

    We evaluated the performance of the Verigene Gram-Negative Blood Culture Nucleic Acid Test (BC-GN; Nanosphere, Northbrook, IL, USA), an automated multiplex assay for rapid identification of positive blood cultures caused by 9 Gram-negative bacteria (GNB) and for detection of 9 genes associated with β-lactam resistance. The BC-GN assay can be performed directly from positive blood cultures with 5 minutes of hands-on and 2 hours of run time per sample. A total of 397 GNB positive blood cultures were analyzed using the BC-GN assay. Of the 397 samples, 295 were simulated samples prepared by inoculating GNB into blood culture bottles, and the remaining were clinical samples from 102 patients with positive blood cultures. Aliquots of the positive blood cultures were tested by the BC-GN assay. The results of bacterial identification between the BC-GN assay and standard laboratory methods were as follows: Acinetobacter spp. (39 isolates for the BC-GN assay/39 for the standard methods), Citrobacter spp. (7/7), Escherichia coli (87/87), Klebsiella oxytoca (13/13), and Proteus spp. (11/11); Enterobacter spp. (29/30); Klebsiella pneumoniae (62/72); Pseudomonas aeruginosa (124/125); and Serratia marcescens (18/21); respectively. From the 102 clinical samples, 104 bacterial species were identified with the BC-GN assay, whereas 110 were identified with the standard methods. The BC-GN assay also detected all β-lactam resistance genes tested (233 genes), including 54 bla(CTX-M), 119 bla(IMP), 8 bla(KPC), 16 bla(NDM), 24 bla(OXA-23), 1 bla(OXA-24/40), 1 bla(OXA-48), 4 bla(OXA-58), and 6 blaVIM. The data shows that the BC-GN assay provides rapid detection of GNB and β-lactam resistance genes in positive blood cultures and has the potential to contributing to optimal patient management by earlier detection of major antimicrobial resistance genes.

  9. Nasopharyngeal carriage of Klebsiella pneumoniae and other Gram-negative bacilli in pneumonia-prone age groups in Semarang, Indonesia.

    PubMed

    Farida, Helmia; Severin, Juliëtte A; Gasem, M Hussein; Keuter, Monique; van den Broek, Peterhans; Hermans, Peter W M; Wahyono, Hendro; Verbrugh, Henri A

    2013-05-01

    Gram-negative bacilli (GNB) cause many cases of pneumonia in Indonesia. We investigated nasopharyngeal carriage of GNB in Semarang, Indonesia. Klebsiella pneumoniae carriage in adults (15%) was higher than in children (7%) (P = 0.004), while that of other GNB was comparable. Poor food and water hygiene are determinants of carriage of these bacteria.

  10. Associative Nitrogen Fixation by Klebsiella spp.: Adhesion Sites and Inoculation Effects on Grass Roots

    PubMed Central

    Haahtela, Kielo; Laakso, Tuula; Korhonen, Timo K.

    1986-01-01

    Adhesion sites on grass roots for Klebsiella strains carrying type 3 or type 1 fimbriae or both were determined. Adhesion of the strains to the roots of Poa pratensis and Festuca rubra was highly localized; the bacteria adhered strongly to root hairs and with a markedly lower efficiency to the surface of the zone of elongation and to the root cap mucilage. No adhesion to the epidermal cells between root hairs was observed. The adhesion sites were identical for the type 3- and 1-fimbriated bacteria and for P. pratensis, F. rubra, and Trifolium pratense. Inoculation of P. pratensis seedlings with Klebsiella pneumoniae strain As resulted in morphological changes in plant roots. The roots of infected plants were heavily covered with root hairs, which often were deformed and branched. Images PMID:16347205

  11. Catalytic Buffering: Development of the Fluoride-Resistant Ureases of Klebsiella pneumoniae

    DTIC Science & Technology

    2005-10-01

    for nickel incorporation into E . coli to produce active urease in the clones. E . coli in vitro mutagenesis was followed by screening of the lysed...urease of the gram-negative enteric bacteria Klebsiella pneumoniae (formerly aerogenes ) was chosen for these studies. The KAU urease is cloned...mutagenesis, creates random DNA point mutations using an E . coli mutator strain. The FR mutant plasmids isolated from this treatment can then be

  12. A simple method for extracting C-phycocyanin from Spirulina platensis using Klebsiella pneumoniae.

    PubMed

    Zhu, Y; Chen, X B; Wang, K B; Li, Y X; Bai, K Z; Kuang, T Y; Ji, H B

    2007-02-01

    C-phycocyanin (C-PC) was extracted from fresh Spirulina platensis by deploying a species of non-pathogenic nitrogen-fixing bacteria, namely, Klebsiella pneumoniae. The algal slurry was neither washed nor centrifuged; the bacterial culture was poured into the slurry, the vessel sealed, and crude C-PC extracted after about 24 h. The extraction was clean and efficient, and the purity and concentration of C-PC proved to be of adequate quality.

  13. Environmental persistence of OXA-48-producing Klebsiella pneumoniae in a French intensive care unit.

    PubMed

    Pantel, Alix; Richaud-Morel, Brigitte; Cazaban, Michel; Bouziges, Nicole; Sotto, Albert; Lavigne, Jean-Philippe

    2016-03-01

    The spread of carbapenemase-producing Gram-negative rods is an emerging global problem. This study describes the epidemiologic features of an outbreak caused by an environmental reservoir of OXA-48-producing Klebsiella pneumoniae caused by persistence of the bacteria during 20 months in an intensive care unit in France. This report emphasizes the importance of early environmental screening to interrupt the transmission of carbapenemase-producingEnterobacteriaceae.

  14. Klebsiella Species Associated with Bovine Mastitis in Newfoundland

    PubMed Central

    Podder, Milka P.; Rogers, Laura; Daley, Peter K.; Keefe, Greg P.; Whitney, Hugh G.; Tahlan, Kapil

    2014-01-01

    Klebsiella spp. is a common cause of bovine mastitis, but information regarding its molecular epidemiology is lacking from many parts of the world. On using mass spectrometry and partial sequencing of the rpoB gene, it was found that over a one year study, K. variicola and Enterobacter cloacae were misidentified as K. pneumoniae in a small number of clinical mastitis (CM) cases from Newfoundland. Results suggest that the currently used standard biochemical/phenotypic tests lack the sensitivity required to accurately discriminate among the three mentioned Gram negative bacteria. In addition, a single strain of K. variicola was associated with CM from one farm in the study as demonstrated by Random Amplified Polymorphic DNA (RAPD) PCR. To the best of our knowledge, K. variicola, which is normally found in the environment, has not been isolated previously from milk obtained from cows with CM. Therefore, it is possible that K. variicola was not detected in milk samples in the past due to the inability of standard tests to discriminate it from other Klebsiella species. PMID:25180510

  15. Klebsiella species associated with bovine mastitis in Newfoundland.

    PubMed

    Podder, Milka P; Rogers, Laura; Daley, Peter K; Keefe, Greg P; Whitney, Hugh G; Tahlan, Kapil

    2014-01-01

    Klebsiella spp. is a common cause of bovine mastitis, but information regarding its molecular epidemiology is lacking from many parts of the world. On using mass spectrometry and partial sequencing of the rpoB gene, it was found that over a one year study, K. variicola and Enterobacter cloacae were misidentified as K. pneumoniae in a small number of clinical mastitis (CM) cases from Newfoundland. Results suggest that the currently used standard biochemical/phenotypic tests lack the sensitivity required to accurately discriminate among the three mentioned Gram negative bacteria. In addition, a single strain of K. variicola was associated with CM from one farm in the study as demonstrated by Random Amplified Polymorphic DNA (RAPD) PCR. To the best of our knowledge, K. variicola, which is normally found in the environment, has not been isolated previously from milk obtained from cows with CM. Therefore, it is possible that K. variicola was not detected in milk samples in the past due to the inability of standard tests to discriminate it from other Klebsiella species.

  16. [Fatal pneumonia caused by carbapenem resistant Klebsiella pneumoniae].

    PubMed

    van Apeldoorn, Marjan; Lettinga, Kamilla; Bernards, Alexandra; Paltansing, Sunita; alNaiemi, Nashwan; Kalpoe, Jayant

    2010-01-01

    A 63-year-old Dutch man became colonized with a carbapenem resistant Klebsiella pneumoniae during a period of hospitalization in India. His recovery in the Netherlands was complicated by pneumonia due to this difficult-to-control multiresistant bacteria to which he eventually succumbed. Carbapenem resistance in Enterobacteriaceae, such as K. pneumoniae, is usually caused by carbapenemase (a betalactamase) production. Carbapenemase producing Enterobacteriaceae (CPE) are spreading throughout the world and cause difficult-to-treat infections that are associated with high mortality. This case report illustrates the clinical challenges associated with infection with these multiresistant Enterobacteriaceae. In the Netherlands, there are no guidelines for detection of CPE and carbapenemase production can frequently go undetected in clinical microbiology laboratories. As a consequence, adequate treatment of CPE infections and infection control measures to prevent the spread of CPE can be delayed. Expeditious development and implementation of existing Dutch draft guidelines for detection methods of CPE is therefore warranted.

  17. Clinical epidemiology of the global expansion of Klebsiella pneumoniae carbapenemases

    PubMed Central

    Munoz-Price, L Silvia; Poirel, Laurent; Bonomo, Robert A; Schwaber, Mitchell J; Daikos, George L; Cormican, Martin; Cornaglia, Giuseppe; Garau, Javier; Gniadkowski, Marek; Hayden, Mary K; Kumarasamy, Karthikeyan; Livermore, David M; Maya, Juan J; Nordmann, Patrice; Patel, Jean B; Paterson, David L; Pitout, Johann; Villegas, Maria Virginia; Wang, Hui; Woodford, Neil; Quinn, John P

    2015-01-01

    Klebsiella pneumoniae carbapenemases (KPCs) were originally identified in the USA in 1996. Since then, these versatile β-lactamases have spread internationally among Gram-negative bacteria, especially K pneumoniae, although their precise epidemiology is diverse across countries and regions. The mortality described among patients infected with organisms positive for KPC is high, perhaps as a result of the limited antibiotic options remaining (often colistin, tigecycline, or aminoglycosides). Triple drug combinations using colistin, tigecycline, and imipenem have recently been associated with improved survival among patients with bacteraemia. In this Review, we summarise the epidemiology of KPCs across continents, and discuss issues around detection, present antibiotic options and those in development, treatment outcome and mortality, and infection control. In view of the limitations of present treatments and the paucity of new drugs in the pipeline, infection control must be our primary defence for now. PMID:23969216

  18. Isolation of KPC 3-producing Enterobacter aerogenes in a patient colonized by MDR Klebsiella pneumoniae.

    PubMed

    Venditti, Carolina; Villa, Laura; Capone, Alessandro; Fortini, Daniela; D'Arezzo, Silvia; Nisii, Carla; Bordi, Eugenio; Puro, Vincenzo; Antonini, Mario; Carattoli, Alessandra; Cataldo, Maria Adriana; Petrosillo, Nicola; Di Caro, Antonino

    2016-10-01

    We describe the interspecies transmission of the plasmid-mediated blaKPC-3 gene, which confers carbapenem resistance, between clinically relevant gram-negative bacteria in a single patient. A KPC-3 producing Enterobacter aerogenes was isolated from a hospitalized patient previously colonized and then infected by a Klebsiella pneumoniae ST101 carrying the blaKPC-3 gene. The strains showed identical plasmids. Since intense horizontal exchanges among bacteria can occur in the gut, clinicians should be aware that patients colonized by carbapenem-resistant K. pneumoniae could become carriers of other carbapenem-resistant Enterobacteriaceae.

  19. Biochemical and Structural Characterization of a Ureidoglycine Aminotransferase in the Klebsiella pneumoniae Uric Acid Catabolic Pathway

    SciTech Connect

    French, Jarrod B.; Ealick, Steven E.

    2010-09-03

    Many plants, fungi, and bacteria catabolize allantoin as a mechanism for nitrogen assimilation. Recent reports have shown that in plants and some bacteria the product of hydrolysis of allantoin by allantoinase is the unstable intermediate ureidoglycine. While this molecule can spontaneously decay, genetic analysis of some bacterial genomes indicates that an aminotransferase may be present in the pathway. Here we present evidence that Klebsiella pneumoniae HpxJ is an aminotransferase that preferentially converts ureidoglycine and an {alpha}-keto acid into oxalurate and the corresponding amino acid. We determined the crystal structure of HpxJ, allowing us to present an explanation for substrate specificity.

  20. Long-term dissemination of acquired AmpC β-lactamases among Klebsiella spp. and Escherichia coli in Portuguese clinical settings.

    PubMed

    Freitas, F; Machado, E; Ribeiro, T G; Novais, Â; Peixe, L

    2014-04-01

    We investigated the occurrence, diversity and molecular epidemiology of genes coding for acquired AmpC β-lactamases (qAmpC) among clinical isolates of Enterobacteriaceae lacking inducible chromosomal AmpCs in Portugal. A total of 675 isolates non-susceptible to broad-spectrum cephalosporins obtained from four hospitals and three community laboratories during a 7-year period (2002-2008) were analysed. The presence of genes coding for qAmpC was investigated by phenotypic criteria, polymerase chain reaction (PCR) and sequencing. Bacterial identification, antibiotic susceptibility testing, conjugation assays and clonal analysis were performed by standard procedures. The presence of bla(qAmpC) genes was detected in 50 % (50/100; 41 Klebsiella pneumoniae, 5 Escherichia coli, 4 Klebsiella oxytoca) of the presumptive qAmpC producers. DHA-1, detected in those species, was the most prevalent qAmpC (94 %, 47/50), being identified since 2003 and throughout the studied period in different institutions. Despite the high clonal diversity observed, three DHA-1-producing Klebsiella spp. clones were more frequently identified. CMY-2 (6 %, 3/50) was observed in B1-E. coli clones. Conjugative transfer was only observed in one (2 %) CMY-2-producing isolate. Most qAmpC producers (94 %, 47/50) co-expressed SHV-type and/or OXA-1 or CTX-M-32 extended-spectrum β-lactamases (ESBLs). To the authors' knowledge, this is the first description of the molecular epidemiology and the long-term dissemination of qAmpC-producing Enterobacteriaceae in Portuguese clinical settings, highlighting an evolution towards a more complex epidemiological situation regarding cephalosporin resistance in Portugal.

  1. Frequency of Klebsiella pneumoniae carbapenemase (KPC) and non-KPC-producing Klebsiella contamination of Healthcare workers and the environment

    PubMed Central

    Rock, Clare; Thom, Kerri A.; Masnick, Max; Johnson, J. Kristie; Harris, Anthony D.; Morgan, Daniel J

    2014-01-01

    We examined contamination of healthcare worker (HCW) gown and gloves after caring for patients with Klebsiella Producing Carbapenemase-producing and non-KPC-producing Klebsiella as a proxy for horizontal transmission. Contamination rate with Klebsiella is similar to MRSA and VRE, with 14% (31/220) of HCW-patient interactions resulting in contamination of gloves and gowns. PMID:24602950

  2. Klebsiella pneumoniae secretes outer membrane vesicles that induce the innate immune response.

    PubMed

    Lee, Je Chul; Lee, Eun Jeoung; Lee, Jung Hwa; Jun, So Hyun; Choi, Chi Won; Kim, Seung Il; Kang, Sang Sun; Hyun, Sunghee

    2012-06-01

    Outer membrane vesicles (OMVs) derived from pathogenic Gram-negative bacteria are an important vehicle for delivery of effector molecules to host cells, but the production of OMVs from Klebsiella pneumoniae, an opportunistic pathogen of both nosocomial and community-acquired infections, and their role in bacterial pathogenesis have not yet been determined. In the present study, we examined the production of OMVs from K. pneumoniae and determined the induction of the innate immune response against K. pneumoniae OMVs. Klebsiella pneumoniae ATCC 13883 produced and secreted OMVs during in vitro culture. Proteomic analysis revealed that 159 different proteins were associated with K. pneumoniae OMVs. Klebsiella pneumoniae OMVs did not inhibit cell growth or induce cell death. However, these vesicles induced expression of proinflammatory cytokine genes such as interleukin (IL)-1β and IL-8 in epithelial cells. An intratracheal challenge of K. pneumoniae OMVs in neutropenic mice resulted in severe lung pathology similar to K. pneumoniae infection. In conclusion, K. pneumoniae produces OMVs like other pathogenic Gram-negative bacteria and K. pneumoniae OMVs are a molecular complex that induces the innate immune response.

  3. [Protective effect of Lactobacillus acidophilus on development of infection, caused by Klebsiella pneumoniae].

    PubMed

    Kostiuk, O P; Chernyshova, L I; Slukvin, I I

    1993-01-01

    The mechanisms of protective action of Lactobacillus have been studied during development of the generalized infection induced by Klebsiella pneumoniae in CBA mice after weaning. The mice were infected intragastrically during the first day after weaning (1 x 10(9) bacterias per mice). Suspensions of Lactobacillus were introduced before and after infection during 10 days (1 x 10(6) bacterias per mice). It has been shown that introduction of Lactobacillus substantially decreased the level of the gut contamination by Klebsiella, prevented generalization of infection and death of animals. Significant higher levels of IgA in the blood serum, IgA and IgM in the gut content, percentage of splenocytes, expressing surface IgM and IgG were observed on the 7th day as compared with those in animals without Lactobacillus. Significantly lower percentage of splenocytes, expressing CD4 antigen was also observed. On the 11th day after infection the mice receiving lactobacillus have shown a tendency to an increase of IgA in the gut content, significantly lower concentrations of IgM in the gut content and a higher level of IgA to the blood serum as compared with the control. Other characteristics were comparable to those of the control group. A conclusion is made that introduction of Lactobacillus prevents development of the Klebsiella infection and protects the immune system from excessive antigenic action.

  4. Detection of drug-resistant Klebsiella pneumoniae in Chinese hares (Lepus sinensis).

    PubMed

    Du, Yingchun; Luo, Jing; Wang, Chengmin; Wen, Qingna; Duan, Mingxing; Zhang, Hong; He, Hongxuan

    2014-01-01

    We investigated an outbreak of acute pneumonia among adult Chinese hares (Lepus sinensis) and diarrhea among juvenile hares in Hebei Province, China, in 2012. Diagnosis was based on necropsy examination, microbial characteristics, biochemical identification, and nucleotide sequence analysis. The isolated bacteria from tissue samples of dead hares were identified as Klebsiella pneumoniae ssp. pneumoniae (K. pneumoniae). This K. pneumoniae was resistant to the antimicrobials imipenem, meropenem, penicillin, and vancomycin, but was highly sensitive to cefepime, cotrimoxazole, and enrofloxacin. Klebsiella pneumoniae is an important opportunistic pathogen, which often causes nosocomial infections in immunocompromised patients. However, the emergence of drug-resistant K. pneumoniae in hares indicates the existence of increasing risk of pathogen transmission between humans and wildlife. Given the close association between wildlife, livestock, and humans, it is important to identify epidemiologic factors associated with infection in these hares to minimize the risk of K. pneumoniae transmission.

  5. Identification and Characterization of Imipenem-Resistant Klebsiella pneumoniae and Susceptible Klebsiella variicola Isolates Obtained from the Same Patient.

    PubMed

    Garza-Ramos, Ulises; Moreno-Dominguez, Stephania; Hernández-Castro, Rigoberto; Silva-Sanchez, Jesús; Barrios, Humberto; Reyna-Flores, Fernando; Sanchez-Perez, Alejandro; Carrillo-Casas, Erika M; Sanchez-León, María Carmen; Moncada-Barron, David

    2016-04-01

    Klebsiella variicola, a bacterium closely genetically related to Klebsiella pneumoniae, is commonly misidentified as K. pneumoniae by biochemical tests. To distinguish between the two bacteria, phylogenetic analysis of the rpoB gene and the identification of unique genes in both bacterial species by multiplex-polymerase chain reaction (PCR) provide the means to reliably identify and genotype K. variicola. In recent years, K. variicola has been described both as the cause of an intrahospital outbreak in a pediatric hospital, which resulted in sepsis in inpatients, and as a frequent cause of bloodstream infections. In the present study, K. pneumoniae and K. variicola were isolated from a unique patient displaying different antimicrobial susceptibility phenotypes and different genotypes of virulence determinants. Eight clinical isolates were obtained at different time intervals; all during a 5-month period. The isolates were identified as K. pneumoniae by an automated identification system. The clinical (biochemical test) and molecular (multiplex-PCR and rpoB gene) characterization identified imipenem resistance in the first six K. pneumoniae ST258 isolates, which encode the SHV-12 cephalosporinase and KPC-3 carbapenemase genes. The two last remaining isolates corresponded to susceptible K. variicola. The bacterial species showed a specific profile of virulence-associated determinants, specifically the fimA, fimH, and ecpRAB fimbrial-encoding genes identified only in K. pneumoniae isolates. However, the entb (enterobactin), mrkD (fimbrial adhesin), uge (epimerase), ureA (urease), and wabG (transferase) genes were shared between both bacterial species. Recent studies attribute a higher mortality rate to K. variicola than to K. pneumonia. This work highlights the identification of K. pneumoniae and the closely related K. variicola isolated from the same patient. The value of distinguishing between these two bacterial species is in their clinical significance, their

  6. Anaerobic bacteria

    MedlinePlus

    Anaerobic bacteria are bacteria that do not live or grow when oxygen is present. In humans, these bacteria ... Goldstein EJ. Diseases caused by non-spore forming anaerobic bacteria. In: Goldman L, Schafer AI, eds. Goldman's Cecil ...

  7. [Investigation of plasmid-mediated quinolone resistance genes in quinolone-resistant Escherichia coli and Klebsiella spp. isolates from bloodstream infections].

    PubMed

    Buruk, Celal Kurtuluş; Öztel Ocak, Hikmet; Bayramoğlu, Gülçin; Aydın, Faruk

    2016-04-01

    One of the treatment options of Escherichia coli and Klebsiella spp. infections which are the most common opportunistic pathogens of gram-negative sepsis is quinolones. Resistance to quinolones which act by disrupting DNA synthesis has been increasing. Horizontal transfer of plasmid-mediated quinolone resistance (PMQR) genes play an important role in the spread of resistance. The data about the prevalence of PMQR genes in our country is quite limited. The aim of this study was to investigate the presence of known PMQR genes namely qnrA, qnrB, qnrC, qnrS, qnrD, aac(6')-Ib-cr, qepA and oqxAB amongst quinolone-resistant E. coli and Klebsiella spp. strains isolated from blood cultures. One hundred twenty seven E.coli and 66 Klebsiella isolates detected as nalidixic acid- and/or ciprofloxacin-resistant by phenotypical methods, from 193 blood samples of 187 patients admitted to Karadeniz Technical University, Faculty of Medicine, Department of Medical Microbiology, Bacteriology Unit of Patient Service Laboratory between January 2012 to August 2013 were included in the study. The presence of PMQR genes were investigated by polymerase chain reaction (PCR) and for the detection of aac(6')-Ib-cr variants PCR-restriction fragment length polymorphism (PCR-RFLP) method was used. The positive bands were sequenced using the same primers, and aligned with formerly defined resistance gene sequences, and confirmed. In the study, 56.7% (72/127) of E.coli and 19.7% (13/66) of Klebsiella spp. isolates, with a total of 44% (85/193) of all the isolates were found to be phenotypically resistant to quinolones. Of the 13 resistant Klebsiella isolates, 11 were K.pneumoniae, and two were K.oxytoca. Extended-spectrum beta-lactamase (ESBL)-producing isolates showed higher resistance (50/80, 62.5%) to quinolones than the negative ones (35/113, 30.9%). The prevalence of quinolone resistance genes among resistant E. coli and Klebsiella spp. isolates was determined as qnrA, 1.4% and 15.4%; qnrB, 4

  8. Emergence of New Delhi Metallo-Beta-Lactamase (NDM-1) and Klebsiella pneumoniae Carbapenemase (KPC-2) in South Africa

    PubMed Central

    Coetzee, Jennifer; Clay, Cornelis G.; Sithole, Sindi; Richards, Guy A.; Poirel, Laurent; Nordmann, Patrice

    2012-01-01

    This report documents emergence of New Delhi metallo-beta-lactamase (NDM-1) and Klebsiella pneumoniae carbapenemase (KPC-2) in K. pneumoniae and Enterobacter cloacae in South Africa. NDM-1 producers have not been described in South Africa, and this is the first instance that KPC producers have been identified in Africa. The two patients infected with these carbapenemase-producing bacteria demised. PMID:22116157

  9. Klebsiella pneumoniae carbapenemases in Enterobacteriaceae: history, evolution, and microbiology concerns.

    PubMed

    Rapp, Robert P; Urban, Carl

    2012-05-01

    Since the discovery of penicillin 80 years ago, gram-negative bacteria have become proficient at evading the lethal activity of β-lactam antibiotics, principally through the production of β-lactamases. The rapid emergence of penicillinases in both gram-positive and gram-negative bacteria led to the development of cephalosporin β-lactam antibiotics, but production of plasmid-mediated extended-spectrum cephalosporinases (or extended-spectrum β-lactamases) and AmpC enzymes resulted in resistance to this drug class. Because carbapenems were the only β-lactam agents active against such extended-spectrum β-lactamase-producing strains, appropriate and inappropriate use soon resulted in Enterobacteriaceae resistance. As a result, two distinct types of carbapenemases-the metallo-β-lactamases and Klebsiella pneumoniae carbapenemases (KPCs)-were soon identified. The KPCs comprise 10 variants that differ from one another by one to three amino acid substitutions (KPC-2 to KPC-11). The KPC-producing Enterobacteriaceae are not only multidrug resistant but are also difficult to detect routinely in the clinical microbiology laboratory. Tigecycline, polymyxins (colistin and polymyxin B), and aminoglycosides are possible candidate therapies for infections caused by KPC-producing organisms, although well-conducted clinical trials are required to fully define their roles in patient management. The shortage of new antimicrobial agents on the immediate horizon suggests that enhanced adherence with infection prevention procedures and antimicrobial stewardship programs are needed to curb patient-to-patient transmission and to reduce the selection of multidrug-resistant bacteria.

  10. Phenotypic and Molecular Characterization of Antimicrobial Resistance in Klebsiella spp. Isolates from Companion Animals in Japan: Clonal Dissemination of Multidrug-Resistant Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae

    PubMed Central

    Harada, Kazuki; Shimizu, Takae; Mukai, Yujiro; Kuwajima, Ken; Sato, Tomomi; Usui, Masaru; Tamura, Yutaka; Kimura, Yui; Miyamoto, Tadashi; Tsuyuki, Yuzo; Ohki, Asami; Kataoka, Yasushi

    2016-01-01

    The emergence of antimicrobial resistance in Klebsiella spp., including resistance to extended-spectrum cephalosporins (ESC) and fluoroquinolones, is of great concern in both human and veterinary medicine. In this study, we investigated the prevalence of antimicrobial resistance in a total of 103 Klebsiella spp. isolates, consisting of Klebsiella pneumoniae complex (KP, n = 89) and K. oxytoca (KO, n = 14) from clinical specimens of dogs and cats in Japan. Furthermore, we characterized the resistance mechanisms, including extended-spectrum β-lactamase (ESBL), plasmid-mediated AmpC β-lactamase (PABL), and plasmid-mediated quinolone resistance (PMQR); and assessed genetic relatedness of ESC-resistant Klebsiella spp. strains by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Antimicrobial susceptibility testing demonstrated that resistance rates to ampicillin, cephalothin, enrofloxacin, ciprofloxacin, trimethoprim/sulfamethoxazole, cefotaxime, gentamicin, tetracycline, chloramphenicol, amoxicillin-clavulanic acid, and cefmetazole were 98.1, 37.9, 37.9, 35.9, 35.0, 34.0, 31.1, 30.1, 28.2, 14.6, and 6.8%, respectively. Phenotypic testing detected ESBLs and/or AmpC β-lactamases in 31 of 89 (34.8%) KP isolates, but not in KO isolates. Resistances to 5 of the 12 antimicrobials tested, as well as the three PMQRs [qnrB, qnrS, and aac(6′)-Ib-cr], were detected significantly more frequently in ESBL-producing KP, than in non-ESBL-producing KP and KO. The most frequent ESBL was CTX-M-15 (n = 13), followed by CTX-M-14 (n = 7), CTX-M-55 (n = 6), SHV-2 (n = 5), CTX-M-2 (n = 2), and CTX-M-3 (n = 2). Based on the rpoB phylogeny, all ESBL-producing strains were identified as K. pneumoniae, except for one CTX-M-14-producing strain, which was identified as K. quasipneumoniae. All of AmpC β-lactamase positive isolates (n = 6) harbored DHA-1, one of the PABLs. Based on MLST and PFGE analysis, ST15 KP clones producing CTX-M-2, CTX-M-15, CTX-M-55, and

  11. [Construction of polyhydroxybutyrate pathway in Klebsiella pneumoniae].

    PubMed

    Guo, Xiaochen; Liu, Hongjuan; Wang, Yanping; Zhang, Jian'an; Liu, Dehua

    2013-10-01

    1,3-propanediol production with the byproduct of biodiesel production is important to increase the economic benefit of biodiesel industry. Accumulation of 3-hydroxypropionaldehyde is one of the key problems in the 1,3-propanediol fermentation process, leading to the cell death and the fermentation abnormal ceasing. Different from the traditional way of reducing the accumulation of the 3-hydroxypropionaldehyde, we introduced the polyhydroxybutyrate pathway into the Klebsiella pneumoniae for the first time to enhance the tolerance of K. pneumoniae to 3-hydroxypropionaldehyde, at the same time, to improve the 1,3-propanediol production. Plasmid pDK containing phbC, phbA, phbB gene was constructed and transformed into K. pneumoniae successfully. PHB was detected in the engineered K. pneumoniae after IPTG induction and its content enhanced with the IPTG concentration increasing. The optimized IPTG concentration was 0.5 mmol/L. The constructed K. pneumoniae could produce 1,3-propanediol normally, at the same time accumulate polyhydroxybutyrate. With the constructed strain, the fermentation proceeds normally with the initial glucose was 70 g/L which the wild type strain stopped growing and the fermentation was ceasing; 1,3-propanediol concentration and yield reached 31.3 g/L and 43.9% at 72 h. Our work is helpful for the deep understanding of 1,3-propanediol metabolic mechanism of Klebsiella pneumoniae, and also provides a new way for strain optimization of Klebsiella pneumoniae.

  12. Complete genome sequence of the lignin-degrading bacterium Klebsiella sp. strain BRL6-2

    PubMed Central

    2014-01-01

    In an effort to discover anaerobic bacteria capable of lignin degradation, we isolated Klebsiella sp. strain BRL6-2 on minimal media with alkali lignin as the sole carbon source. This organism was isolated anaerobically from tropical forest soils collected from the Bisley watershed at the Ridge site in the El Yunque National Forest in Puerto Rico, USA, part of the Luquillo Long-Term Ecological Research Station. At this site, the soils experience strong fluctuations in redox potential and are characterized by cycles of iron oxidation and reduction. Genome sequencing was targeted because of its ability to grow on lignin anaerobically and lignocellulolytic activity via in vitro enzyme assays. The genome of Klebsiella sp. strain BRL6-2 is 5.80 Mbp with no detected plasmids, and includes a relatively small arsenal of genes encoding lignocellulolytic carbohydrate active enzymes. The genome revealed four putative peroxidases including glutathione and DyP-type peroxidases, and a complete protocatechuate pathway encoded in a single gene cluster. Physiological studies revealed Klebsiella sp. strain BRL6-2 to be relatively stress tolerant to high ionic strength conditions. It grows in increasing concentrations of ionic liquid (1-ethyl-3-methyl-imidazolium acetate) up to 73.44 mM and NaCl up to 1.5 M. PMID:25566348

  13. Recent Research Examining Links Among Klebsiella pneumoniae from Food, Food Animals, and Human Extraintestinal Infections.

    PubMed

    Davis, Gregg S; Price, Lance B

    2016-06-01

    Klebsiella pneumoniae is a colonizer of livestock, a contaminant of retail meats and vegetables, and a cause of extraintestinal infections in humans. Antibiotic-resistant strains of K. pneumoniae are becoming increasingly prevalent among hospital and community-acquired infections. Antibiotics are used extensively in conventional food-animal production, where they select for antibiotic-resistant bacteria. Antibiotic-resistant K. pneumoniae has been isolated from livestock as well as from a variety of retail meats, seafood, and vegetables. Furthermore, recent phylogenetic analyses suggest close relationships between K. pneumoniae from humans and livestock. Therefore, it is essential that we quantify the contribution of foodborne K. pneumoniae to antibiotic-resistant human infections.

  14. Biological Treatment of Cyanide by Using
Klebsiella pneumoniae Species

    PubMed Central

    Bilkay, Isil Seyis

    2016-01-01

    Summary In this study, optimization conditions for cyanide biodegradation by Klebsiella pneumoniae strain were determined to be 25 °C, pH=7 and 150 rpm at the concentration of 0.5 mM potassium cyanide in the medium. Additionally, it was found that K. pneumoniae strain is not only able to degrade potassium cyanide, but also to degrade potassium hexacyanoferrate(II) trihydrate and sodium ferrocyanide decahydrate with the efficiencies of 85 and 87.5%, respectively. Furthermore, this strain degraded potassium cyanide in the presence of different ions such as magnesium, nickel, cobalt, iron, chromium, arsenic and zinc, in variable concentrations (0.1, 0.25 and 0.5 mM) and as a result the amount of the bacteria in the biodegradation media decreased with the increase of ion concentration. Lastly, it was also observed that sterile crude extract of K. pneumoniae strain degraded potassium cyanide on the fifth day of incubation. Based on these results, it is concluded that both culture and sterile crude extract of K. pnemoniae will be used in cyanide removal from different wastes. PMID:28115902

  15. The secondary resistome of multidrug-resistant Klebsiella pneumoniae

    PubMed Central

    Jana, Bimal; Cain, Amy K.; Doerrler, William T.; Boinett, Christine J.; Fookes, Maria C.; Parkhill, Julian; Guardabassi, Luca

    2017-01-01

    Klebsiella pneumoniae causes severe lung and bloodstream infections that are difficult to treat due to multidrug resistance. We hypothesized that antimicrobial resistance can be reversed by targeting chromosomal non-essential genes that are not responsible for acquired resistance but essential for resistant bacteria under therapeutic concentrations of antimicrobials. Conditional essentiality of individual genes to antimicrobial resistance was evaluated in an epidemic multidrug-resistant clone of K. pneumoniae (ST258). We constructed a high-density transposon mutant library of >430,000 unique Tn5 insertions and measured mutant depletion upon exposure to three clinically relevant antimicrobials (colistin, imipenem or ciprofloxacin) by Transposon Directed Insertion-site Sequencing (TraDIS). Using this high-throughput approach, we defined three sets of chromosomal non-essential genes essential for growth during exposure to colistin (n = 35), imipenem (n = 1) or ciprofloxacin (n = 1) in addition to known resistance determinants, collectively termed the “secondary resistome”. As proof of principle, we demonstrated that inactivation of a non-essential gene not previously found linked to colistin resistance (dedA) restored colistin susceptibility by reducing the minimum inhibitory concentration from 8 to 0.5 μg/ml, 4-fold below the susceptibility breakpoint (S ≤ 2 μg/ml). This finding suggests that the secondary resistome is a potential target for developing antimicrobial “helper” drugs that restore the efficacy of existing antimicrobials. PMID:28198411

  16. The secondary resistome of multidrug-resistant Klebsiella pneumoniae.

    PubMed

    Jana, Bimal; Cain, Amy K; Doerrler, William T; Boinett, Christine J; Fookes, Maria C; Parkhill, Julian; Guardabassi, Luca

    2017-02-15

    Klebsiella pneumoniae causes severe lung and bloodstream infections that are difficult to treat due to multidrug resistance. We hypothesized that antimicrobial resistance can be reversed by targeting chromosomal non-essential genes that are not responsible for acquired resistance but essential for resistant bacteria under therapeutic concentrations of antimicrobials. Conditional essentiality of individual genes to antimicrobial resistance was evaluated in an epidemic multidrug-resistant clone of K. pneumoniae (ST258). We constructed a high-density transposon mutant library of >430,000 unique Tn5 insertions and measured mutant depletion upon exposure to three clinically relevant antimicrobials (colistin, imipenem or ciprofloxacin) by Transposon Directed Insertion-site Sequencing (TraDIS). Using this high-throughput approach, we defined three sets of chromosomal non-essential genes essential for growth during exposure to colistin (n = 35), imipenem (n = 1) or ciprofloxacin (n = 1) in addition to known resistance determinants, collectively termed the "secondary resistome". As proof of principle, we demonstrated that inactivation of a non-essential gene not previously found linked to colistin resistance (dedA) restored colistin susceptibility by reducing the minimum inhibitory concentration from 8 to 0.5 μg/ml, 4-fold below the susceptibility breakpoint (S ≤ 2 μg/ml). This finding suggests that the secondary resistome is a potential target for developing antimicrobial "helper" drugs that restore the efficacy of existing antimicrobials.

  17. Immunoglobulin M-enriched intravenous polyclonal immunoglobulins reduce bacteremia following Klebsiella pneumoniae infection in an acute respiratory distress syndrome rat model.

    PubMed

    Lachmann, R A; van Kaam, A H L C; Haitsma, J J; Verbrugge, S J C; Delreu, F; Lachmann, B

    2004-06-01

    Mechanical ventilation is known to induce bacterial translocation from the lung into the systemic circulation. This study determined the effect of immunoglobulin M (IgM)-enriched polyclonal immunoglobulins on bacteremia due to ventilation-induced translocation in an acute respiratory distress syndrome (ARDS) rat model with Klebsiella-induced pneumonia. After whole lung lavage, Sprague-Dawley rats intravenously received either a high dose or a low dose of an immunoglobulin preparation, or an albumin solution as control, followed by an intratracheal injection of a Klebsiella pneumoniae solution. Blood colony-forming units (CFUs) in the treatment groups were significantly lower during the 3-hour ventilation period compared to the control group. The authors conclude that IgM-enriched polyclonal immunoglobulins lead to a reduction of bacteria in blood of surfactant-deficient, ventilated rats infected with Klebsiella pneumoniae.

  18. Role of hydrogen generation by Klebsiella pneumoniae in the oral cavity.

    PubMed

    Kanazuru, Tomoko; Sato, Eisuke F; Nagata, Kumiko; Matsui, Hiroshi; Watanabe, Kunihiko; Kasahara, Emiko; Jikumaru, Mika; Inoue, June; Inoue, Masayasu

    2010-12-01

    Some gastrointestinal bacteria synthesize hydrogen (H(2)) by fermentation. Despite the presence of bactericidal factors in human saliva, a large number of bacteria also live in the oral cavity. It has never been shown that oral bacteria also produce H(2) or what role H(2) might play in the oral cavity. It was found that a significant amount of H(2) is synthesized in the oral cavity of healthy human subjects, and that its generation is enhanced by the presence of glucose but inhibited by either teeth brushing or sterilization with povidone iodine. These observations suggest the presence of H(2)-generating bacteria in the oral cavity. The screening of commensal bacteria in the oral cavity revealed that a variety of anaerobic bacteria generate H(2). Among them, Klebsiella pneumoniae (K. pneumoniae) generated significantly large amounts of H(2) in the presence of glucose. Biochemical analysis revealed that various proteins in K. pneumoniae are carbonylated under standard culture conditions, and that oxidative stress induced by the presence of Fe(++) and H(2)O(2) increases the number of carbonylated proteins, particularly when their hydrogenase activity is inhibited by KCN. Inhibition of H(2) generation markedly suppresses the growth of K. pneumoniae. These observations suggest that H(2) generation and/or the reduction of oxidative stress is important for the survival and growth of K. pneumoniae in the oral cavity.

  19. Normal anti-Klebsiella lymphocytotoxicity in ankylosing spondylitis

    SciTech Connect

    Kinsella, T.D.; Fritzler, M.J.; Lewkonia, R.M.

    1986-03-01

    We compared in vitro lymphocytotoxicity (LCT) of peripheral blood lymphocytes (PBL), obtained from patients with ankylosing spondylitis (AS) and normal controls (NC). Assays were performed with antibacterial antisera prepared from AS- and NC-derived Klebsiella and coliforms Escherichia coli. LCT assessed by eosin staining was not significantly different in PBL of 12 AS patients and 28 controls when reacted with 3 Klebsiella and 1 E coli antisera. LCT assessed by /sup 51/Cr release was not significantly different for PBL of 20 age- and sex-matched pairs of AS patients and NC when reacted with 3 Klebsiella and 1 E coli antisera. Similarly, LCT-/sup 51/Cr of PBL of 15 matched AS and NC pairs was not significantly different for anti-K21, a serotype putatively implicated in Klebsiella-HLA-B27 antigenic cross-reactivity. Our results do not support the notion of molecular mimicry between Klebsiella and B27 in the pathogenesis of primary AS.

  20. The formation of germtubes by Candida albicans, when grown with Staphylococcus pyogene, Escherichia coli, Klebsiella pneumoniae, Lactobacilius acidophilus and Proteus vulgaris.

    PubMed

    Purohit, B C; Joshi, K R; Ramdeo, I N; Bharadwaj, T P

    1977-12-31

    The formation of germtubes by twelve clinical isolates of C. albicans was studied in human serum containing per millilitre 10(3) to 10(9) organisms as: Staphylococcus pyegene, Escherichia coli, Klebsiella pneumoniae, Lactobacillus acidophilus and Proteus vulgaris. All the five bacteria inhibited formation of germtubes by C. albicans at all concentrations and the percent germtube formed diminished with increasing concentration of the bacteria. Lactobacillus acidophilus inhibited the formation of germtubes maximally followed by Staphylococcus pyogene, Escherichia coli and Klebsiella pneumoniae. Proteus vulgaris in the concentrations of 10(3) to 10(7) bacteria per millilitre produced only insignificant inhibition of formation of germtubes by C. albicans. Since germtubes of C. albicans are invasive, it is suggested that inhibition of "blastospore-germtube transformation" may be significantly responsible for prevention of infection by C. albicans by coexisting bacterial flora.

  1. Description of Klebsiella quasipneumoniae sp. nov., isolated from human infections, with two subspecies, Klebsiella quasipneumoniae subsp. quasipneumoniae subsp. nov. and Klebsiella quasipneumoniae subsp. similipneumoniae subsp. nov., and demonstration that Klebsiella singaporensis is a junior heterotypic synonym of Klebsiella variicola.

    PubMed

    Brisse, Sylvain; Passet, Virginie; Grimont, Patrick A D

    2014-09-01

    Strains previously classified as members of Klebsiella pneumoniae phylogroups KpI, KpII-A, KpII-B and KpIII were characterized by 16S rRNA (rrs) gene sequencing, multilocus sequence analysis based on rpoB, fusA, gapA, gyrA and leuS genes, average nucleotide identity and biochemical characteristics. Phylogenetic analysis demonstrated that KpI and KpIII corresponded to K. pneumoniae and Klebsiella variicola, respectively, whereas KpII-A and KpII-B formed two well-demarcated sequence clusters distinct from other members of the genus Klebsiella. Average nucleotide identity between KpII-A and KpII-B was 96.4 %, whereas values lower than 94 % were obtained for both groups when compared with K. pneumoniae and K. variicola. Biochemical properties differentiated KpII-A, KpII-B, K. pneumoniae and K. variicola, with acid production from adonitol and l-sorbose and ability to use 3-phenylproprionate, 5-keto-d-gluconate and tricarballylic acid as sole carbon sources being particularly useful. Based on their genetic and phenotypic characteristics, we propose the names Klebsiella quasipneumoniae subsp. quasipneumoniae subsp. nov. and K. quasipneumoniae subsp. similipneumoniae subsp. nov. for strains of KpII-A and KpII-B, respectively. The type strain of K. quasipneumoniae sp. nov. and of K. quasipneumoniae subsp. quasipneumoniae subsp. nov. is 01A030(T) ( = SB11(T) = CIP 110771(T) = DSM 28211(T)). The type strain of K. quasipneumoniae subsp. similipneumoniae subsp. nov. is 07A044(T) ( = SB30(T) = CIP 110770(T) = DSM 28212(T)). Both strains were isolated from human blood cultures. This work also showed that Klebsiella singaporensis is a junior heterotypic synonym of K. variicola.

  2. First identification of a patient colonized with Klebsiella pneumoniae carrying blaNDM-1 in Taiwan.

    PubMed

    Wu, Hua-Shin; Chen, Te-Li; Chen, Isaac Chun-Jen; Huang, Mu-Shun; Wang, Fu-Der; Fung, Chang-Phone; Lee, Shou-Dong

    2010-11-01

    New Delhi metallo-β-lactamase 1 (NDM-1) is a novel type of metallo-β-lactamase (MBL). Enterobacteriaceae carrying this NDM-1 encoding gene, bla(NDM-1), have been identified worldwide. Bacteria carrying bla(NDM-1) are not only resistant to carbapenem, but also highly resistant to many classes of antibiotics, which indicate the importance of prompt identification of these bacteria and implementation of strict infection control measures to prevent their transmission. Here, we report the first identification and management of a patient colonized with Klebsiella pneumoniae carrying bla(NDM-1) in Taiwan, who returned from New Delhi where he had been hospitalized for a gun-shot injury.

  3. Genomic and Functional Characterization of qnr-Encoding Plasmids from Municipal Wastewater Biosolid Klebsiella pneumoniae Isolates

    PubMed Central

    Kaplan, Ella; Sela, Noa; Doron-Faigenboim, Adi; Navon-Venezia, Shiri; Jurkevitch, Edouard; Cytryn, Eddie

    2015-01-01

    Municipal wastewater treatment facilities are considered to be “hotspots” for antibiotic resistance, since they conjoin high densities of environmental and fecal bacteria with selective pressure in the form of sub-therapeutic concentrations of antibiotics. Discharged effluents and biosolids from these facilities can disseminate antibiotic resistant genes to terrestrial and aquatic environments, potentially contributing to the increasing global trend in antibiotic resistance. This phenomenon is especially pertinent when resistance genes are associated with mobile genetic elements such as conjugative plasmids, which can be transferred between bacterial phyla. Fluoroquinolones are among the most abundant antibiotic compounds detected in wastewater treatment facilities, especially in biosolids, where due to their hydrophobic properties they accumulate to concentrations that may exceed 40 mg/L. Although fluoroquinolone resistance is traditionally associated with mutations in the gyrA/topoisomerase IV genes, there is increasing evidence of plasmid-mediated quinolone resistance, which is primarily encoded on qnr genes. In this study, we sequenced seven qnr-harboring plasmids from a diverse collection of Klebsiella strains, isolated from dewatered biosolids from a large wastewater treatment facility in Israel. One of the plasmids, termed pKPSH-11XL was a large (185.4 kbp), multi-drug resistance, IncF-type plasmid that harbored qnrB and 10 additional antibiotic resistance genes that conferred resistance to five different antibiotic families. It was highly similar to the pKPN3-like plasmid family that has been detected in multidrug resistant clinical Klebsiella isolates. In contrast, the six additional plasmids were much smaller (7–9 Kbp) and harbored a qnrS -type gene. These plasmids were highly similar to each other and closely resembled pGNB2, a plasmid isolated from a German wastewater treatment facility. Comparative genome analyses of pKPSH-11XL and other pKPN3

  4. DETECTION OF CTX-M GENE ANTIBIOTICS RESISTANCE IN KLEBSIELLA PNEUMONIA ISOLATES OF HOSPITALS IN ADJARA (GEORGIA).

    PubMed

    Koiava, T; Gonçalves, D; Palmeira, J; Arobelidze, K; Tediashvili, M; Akhvlediani, L; Ferreira, H

    2016-09-01

    Research describing the epidemiology of antibiotic resistant microbes is vital to the proactive development of new antimicrobial agents. In the last years, CTX-M extended-spectrum β-lactamases (ESBLs) have emerged worldwide and have replaced classical TEM and SHV-type ESBLs in many countries. CTX-M-15 is currently the most frequent, with a pandemic distribution, and its rapid spread is facilitated by incorporation of resistance genes in mobile genetic elements. The ESBL is efficacious in Gram-negative bacteria and thus closely associated with nosocomial environments, often colonizing the intestines, particularly in older and dependent patients. Little is known about the CTX-M ESBLs among Klebsiella pneumonia in Adjara. Our paper describes the detected and characterized ESBLs among Klebsiella pneumonia isolates from patients in two different hospitals in Adjara.

  5. Klebsiella singaporensis sp. nov., a novel isomaltulose-producing bacterium.

    PubMed

    Li, Xianzhen; Zhang, Daohai; Chen, Feng; Ma, Jie; Dong, Yihu; Zhang, Lianhui

    2004-11-01

    Cells of strain LX3(T), isolated from soil, were Gram-negative, facultatively anaerobic, non-motile, capsulated and non-endospore-forming straight rods, able to grow at 10 degrees C, unable to produce gas from lactose at 45 degrees C and unable to produce indole. The isolate converted sucrose to isomaltulose and did not produce detectable glucose by-products. The G+C content of the DNA was 56.4 mol%. Furthermore, comparison of 16S rRNA and rpoB gene sequences showed that the isolate clearly belongs to the genus Klebsiella. The closest phylogenetic relative was Klebsiella pneumoniae, there being 99.3 and 97.5 % similarity in 16S rRNA and rpoB gene sequences, respectively. DNA-DNA hybridization analysis demonstrated a very low level of relatedness to other members of the genus Klebsiella, indicating that the isolated strain and other species in the genus Klebsiella were not related at the species level. The isolate could be differentiated from other previously described members of the genus Klebsiella on the basis of phenotypic differences and 16S rRNA and rpoB gene sequence divergence, together with DNA-DNA reassociation data. Therefore, it is proposed that strain LX3(T) (=DSM 16265(T)=JCM 12419(T)) should be classified as the type strain of a novel species of genus Klebsiella, Klebsiella singaporensis sp. nov.

  6. Isolation and Antimicrobial Testing of Aeromonas spp., Citrobacter spp., Cronobacter spp., Enterobacter spp., Escherichia spp., Klebsiella spp., and Trabulsiella spp. from the Gallbladder of Pigs.

    PubMed

    Evangelopoulou, Grammato; Filioussis, Georgios; Kritas, Spyridon; Kantere, Maria; Burriel, Angeliki R

    2015-01-01

    The presence of Gram-negative bacteria species, other than Salmonella spp., in the gallbladder of pigs was examined. Isolated Gram-negative bacteria were assigned to species using the Microgen™ GnA+B-ID Systems. Of the 64 isolated strains 43 were identified as Escherichia coli, seven as Enterobacter spp., three each as Klebsiella spp., Citrobacterfreundii, Aeromonas hydrophila and Cronobacter sakazakii and one each as Escherichiafergusonii and Trabulsiella guamensis. Their antibiograms showed very high resistance to ampicillin, amoxicillin, tetracycline, chloramphenicol and sulfamethoxazole/trimethoprim. It was concluded that the pigs' gallbladder is a reservoir of potentially pathogenic Gram-negative bacteria for pork consumers.

  7. Characterization of Klebsiella sp. strain 10982, a colonizer of humans that contains novel antibiotic resistance alleles and exhibits genetic similarities to plant and clinical Klebsiella isolates.

    PubMed

    Hazen, Tracy H; Zhao, LiCheng; Sahl, Jason W; Robinson, Gwen; Harris, Anthony D; Rasko, David A; Johnson, J Kristie

    2014-01-01

    A unique Klebsiella species strain, 10982, was cultured from a perianal swab specimen obtained from a patient in the University of Maryland Medical Center intensive care unit. Klebsiella sp. 10982 possesses a large IncA/C multidrug resistance plasmid encoding a novel FOX AmpC β-lactamase designated FOX-10. A novel variant of the LEN β-lactamase was also identified. Genome sequencing and bioinformatic analysis demonstrated that this isolate contains genes associated with nitrogen fixation, allantoin metabolism, and citrate fermentation. These three gene regions are typically present in either Klebsiella pneumoniae clinical isolates or Klebsiella nitrogen-fixing endophytes but usually not in the same organism. Phylogenomic analysis of Klebsiella sp. 10982 and sequenced Klebsiella genomes demonstrated that Klebsiella sp. 10982 is present on a branch that is located intermediate between the genomes of nitrogen-fixing endophytes and K. pneumoniae clinical isolates. Metabolic features identified in the genome of Klebsiella sp. 10982 distinguish this isolate from other Klebsiella clinical isolates. These features include the nitrogen fixation (nif) gene cluster, which is typically present in endophytic Klebsiella isolates and is absent from Klebsiella clinical isolates. Additionally, the Klebsiella sp. 10982 genome contains genes associated with allantoin metabolism, which have been detected primarily in K. pneumoniae isolates from liver abscesses. Comparative genomic analysis of Klebsiella sp. 10982 demonstrated that this organism has acquired genes conferring new metabolic strategies and novel antibiotic resistance alleles, both of which may enhance its ability to colonize the human body.

  8. Two distinct sensing pathways allow recognition of Klebsiella pneumoniae by Dictyostelium amoebae.

    PubMed

    Lima, Wanessa C; Balestrino, Damien; Forestier, Christiane; Cosson, Pierre

    2014-03-01

    Recognition of bacteria by metazoans is mediated by receptors that recognize different types of microorganisms and elicit specific cellular responses. The soil amoebae Dictyostelium discoideum feeds upon a variable mixture of environmental bacteria, and it is expected to recognize and adapt to various food sources. To date, however, no bacteria-sensing mechanisms have been described. In this study, we isolated a Dictyostelium mutant (fspA KO) unable to grow in the presence of non-capsulated Klebsiella pneumoniae bacteria, but growing as efficiently as wild-type cells in the presence of other bacteria, such as Bacillus subtilis. fspA KO cells were also unable to respond to K. pneumoniae and more specifically to bacterially secreted folate in a chemokinetic assay, while they responded readily to B. subtilis. Remarkably, both WT and fspA KO cells were able to grow in the presence of capsulated LM21 K. pneumoniae, and responded to purified capsule, indicating that capsule recognition may represent an alternative, FspA-independent mechanism for K. pneumoniae sensing. When LM21 capsule synthesis genes were deleted, growth and chemokinetic response were lost for fspA KO cells, but not for WT cells. Altogether, these results indicate that Dictyostelium amoebae use specific recognition mechanisms to respond to different K. pneumoniae elements.

  9. The capsular network of Klebsiella pneumoniae.

    PubMed

    Cassone, A; Garaci, E

    1977-06-01

    Attempts at improving chemical fixation for electron-microscopic observation of the capsule of Klebsiella pneumoniae were made. The capsule was preserved by using alcian blue - lanthanum and tris-(1-aziridinyl) phosphine oxide (TAPO) - aldehyde - osmium procedures. Despite the different retention of the overall capsular material and minor variations in morphological details, in both cases the interpretation of ultrastructural patterns suggested that the capsule be composed of a meshed network of thin polysaccharide fibrils radiating from the cell wall. This organization is in keeping with all recognized chemical properties of bacterial polysaccharide capsules or, at least, does not contradict them. Moreover, an effective preservation of bacterial structures other than capsule has been obtained, mostly in specimens fixed by the TAPO-aldehyde-osmium method, a fact which gives further reliability to the technical approach used for capsule visualization.

  10. CHARACTERISTICS OF KLEBSIELLA FROM TEXTILE FINISHING PLANT EFFLUENTS

    EPA Science Inventory

    Klebsiella strains are found in abnormally high numbers in a stream receiving wastewater from a textile finishing plant. Representative strains are randomly selected to determine biochemical, serotype, and virulence patterns. All strains conform to the commonly accepted biochemic...

  11. Cefotaxime resistance and outcome of Klebsiella spp bloodstream infection.

    PubMed

    Ortega, M; Marco, F; Soriano, A; Almela, M; Martínez, J A; López, J; Pitart, C; Mensa, J

    2011-12-01

    We attempt to describe the epidemiology and outcome associated with cefotaxime-resistant (CTX-R) Klebsiella spp bacteraemia. Klebsiella spp bloodstream infection episodes prospectively collected through a blood culture surveillance programme from January 1991 to December 2008 in a single institution were analysed. A total of 910 monomicrobial episodes of Klebsiella spp bacteraemia were identified during the study period. The most important sources were from urinary tract infection, unknown sources, billiary focus and catheter related infection. There were 112 (12%) CTX-R isolates. Out of 112 isolates, 98 were CTX-R by Extended-Spectrum β-Lactamase production. Shock on presentation and mortality were significantly more frequent in CTX-R than in CTX susceptible isolates. Inappropriate empirical therapy was received in 50 (45%) cases in the CTX-R Klebsiella spp group (13 cases of death, 26%). Predictive factors associated with CTX-R Klebsiella spp isolate were: previous β-lactam therapy (OR = 4.16), nosocomial acquired bacteraemia (OR = 1.93), solid organ trasplantation (OR = 2.09) and shock (OR = 1.90). Independent risk factors associated with mortality in Klebsiella spp bacteraemia were: age (OR = 1.03), liver cirrhosis (OR = 2.63), ultimately or rapidly fatal prognosis of underlying disease (OR = 2.44), shock (OR = 8.60), pneumonia (OR = 4.96) or intraabdominal (OR = 3.85) source of bacteraemia and CTX-R isolate (OR = 4.63). Klebsiella spp is an important cause of bloodstream infection. CTX-R isolates have been increasing since 2000. CTX-R is an independent factor associated with mortality in Klebsiella spp bacteraemia.

  12. Susceptibility of chemostat-grown Yersinia enterocolitica and Klebsiella pneumoniae to chlorine dioxide.

    PubMed Central

    Harakeh, M S; Berg, J D; Hoff, J C; Matin, A

    1985-01-01

    The resistance of bacteria to antimicrobial agents could be influenced by growth environment. The susceptibility of two enteric bacteria, Yersinia enterocolitica and Klebsiella pneumoniae, to chlorine dioxide was investigated. These organisms were grown in a defined medium in a chemostat and the influence of growth rate, temperature, and cell density on the susceptibility was studied. All inactivation experiments were conducted with a dose of 0.25 mg of chlorine dioxide per liter in phosphate-buffered saline at pH 7.0 and 23 degrees C. The results indicated that populations grown under conditions that more closely approximate natural aquatic environments, e.g., low temperatures and growth at submaximal rates caused by nutrient limitation, were most resistant. The conclusion from this study is that antecedent growth conditions have a profound effect on the susceptibility of bacteria to disinfectants, and it is more appropriate to use the chemostat-grown bacteria as test organisms to evaluate the efficacy of a certain disinfectant. PMID:3883899

  13. An observational study of phagocytes and Klebsiella pneumoniae relationships: different behaviors.

    PubMed

    Maisonneuve, Elodie; Cateau, Estelle; Delouche, Marion; Quellard, Nathalie; Rodier, Marie-Helene

    2017-01-10

    Klebsiella pneumoniae is a bacterium that can be in relation with free living amoebae like Acanthamoeba castellanii in natural environments such as soil and water. This pathogen, which is responsible for community-acquired pneumonia and for nosocomial infections, also has interactions with host defense mechanisms like macrophages. As it has been shown that A. castellanii shares some traits with macrophages, in particular the ability to phagocyte bacteria, we have studied the uptake and the fate of the bacteria after contact with the two phagocytic cells. In our conditions, K. pneumoniae growth was increased in coculture in presence of A. castellanii or Thp-1 macrophagic cells and bacterial development was also increased by A. castellanii supernatant. In addition, we showed that the presence of the bacteria had a negative effect on the macrophages whereas it does not affect amoeba viability. Using gentamicin, which kills bacteria outside cells, we showed that only macrophages were able to internalize K. pneumoniae. This result was confirmed by electron microscopy. We have consequently reported some differences in bacterial uptake and internalization between a free living amoeba and macrophagic cells, highlighting the fact that results obtained with this amoebal model should not be extrapolated to the relationships between K. pneumoniae and macrophages.

  14. Retrospective investigation of the clinical effects of tazobactam/piperacillin and sulbactam/ampicillin on aspiration pneumonia caused by Klebsiella pneumoniae.

    PubMed

    Tsukada, Hiroki; Sakai, Kunihiko; Cho, Hiromi; Kimura, Yuka; Tetsuka, Takafumi; Nakajima, Haruhiko; Ito, Kazuhiko

    2012-10-01

    Klebsiella pneumoniae is an important causative bacterium of aspiration pneumonia in many elderly patients. We retrospectively investigated the clinical effects of the early treatment of aspiration pneumonia and background factors in 24 patients from whom Klebsiella pneumoniae was isolated. Sulbactam/ampicillin (SBT/ABPC) was selected for early treatment in 12 of the 24 patients diagnosed with aspiration pneumonia, and tazobactam/piperacillin (TAZ/PIPC) was selected for the other patients. The effective rates and success rates of early treatment were significantly higher in the TAZ/PIPC group than in the SBT/ABPC group (p = 0.003 and 0.027, respectively). Although no significant difference was noted because of the limited number of cases, the survival rates after 30 days were 91.7 and 58.3 % in the TAZ/PIPC and SBT/ABPC groups, respectively. Several bacteria isolated with Klebsiella pneumoniae were resistant bacteria, such as methicillin-resistant Staphylococcus aureus or Pseudomonas aeruginosa, and no anaerobe or extended-spectrum β-lactamase-producing Klebsiella pneumoniae was isolated. Thirteen and 11 of the 24 cases were classified as healthcare-associated pneumonia (HCAP) and hospital-acquired pneumonia (HAP), respectively, with no case classified as community-acquired pneumonia (CAP). As population aging progresses, the frequency of aspiration pneumonia classified as HCAP will increase. To cover anaerobes, it is necessary to select antibacterial drugs, such as TAZ/PIPC, for early treatment in consideration of resistant gram-negative bacteria to improve the outcome, and not drugs with weak activity against these bacteria.

  15. Modeling Meropenem Treatment, Alone and in Combination with Daptomycin, for KPC-Producing Klebsiella pneumoniae Strains with Unusually Low Carbapenem MICs.

    PubMed

    Gagetti, P; Pasteran, F; Martinez, M P; Fatouraei, M; Gu, J; Fernandez, R; Paz, L; Rose, W E; Corso, A; Rosato, A E

    2016-08-01

    Klebsiella pneumoniae strains producing K. pneumoniae carbapenemase (KPC) cause serious infections in debilitated and immunocompromised patients and are associated with prolonged hospital stays and increased mortality rates. Daptomycin is a lipopeptide used against Staphylococcus aureus infection and considered inactive against Gram-negative bacteria. We investigated the effectiveness of a daptomycin-meropenem combination by synergy kill curve and a pharmacokinetic/pharmacodynamic model. The combination may represent a novel therapeutic strategy against infections caused by KPC-producing K. pneumoniae strains.

  16. Persistence of nasal colonization with human pathogenic bacteria and associated antimicrobial resistance in the German general population

    PubMed Central

    Köck, R.; Werner, P.; Friedrich, A.W.; Fegeler, C.; Becker, K.; Bindewald, O.; Bui, T.T.; Eckhoff, C.; Epping, R.; Kähmann, L.; Meurer, M.; Steger, J.; von Auenmüller, L.

    2015-01-01

    The nares represent an important bacterial reservoir for endogenous infections. This study aimed to assess the prevalence of nasal colonization by different important pathogens, the associated antimicrobial susceptibility and risk factors. We performed a prospective cohort study among 1878 nonhospitalized volunteers recruited from the general population in Germany. Participants provided nasal swabs at three time points (each separated by 4–6 months). Staphylococcus aureus, Enterobacteriaceae and important nonfermenters were cultured and subjected to susceptibility testing. Factors potentially influencing bacterial colonization patterns were assessed. The overall prevalence of S. aureus, Enterobacteriaceae and nonfermenters was 41.0, 33.4 and 3.7%, respectively. Thirteen participants (0.7%) were colonized with methicillin-resistant S. aureus. Enterobacteriaceae were mostly (>99%) susceptible against ciprofloxacin and carbapenems (100%). Extended-spectrum β-lactamase–producing isolates were not detected among Klebsiella oxytoca, Klebsiella pneumoniae and Escherichia coli. Several lifestyle- and health-related factors (e.g. household size, travel, livestock density of the residential area or occupational livestock contact, atopic dermatitis, antidepressant or anti-infective drugs) were associated with colonization by different microorganisms. This study unexpectedly demonstrated high nasal colonization rates with Enterobacteriaceae in the German general population, but rates of antibiotic resistance were low. Methicillin-resistant S. aureus carriage was rare but highly associated with occupational livestock contact. PMID:26862431

  17. Genomic identification of nitrogen-fixing Klebsiella variicola, K. pneumoniae and K. quasipneumoniae.

    PubMed

    Chen, Mingyue; Li, Yuanyuan; Li, Shuying; Tang, Lie; Zheng, Jingwu; An, Qianli

    2016-01-01

    It was difficult to differentiate Klebsiella pneumoniae, K. quasipneumoniae and K. variicola by biochemical and phenotypic tests. Genomics increase the resolution and credibility of taxonomy for closely-related species. Here, we obtained the complete genome sequence of the K. variicola type strain DSM 15968(T) (=F2R9(T)). The genome of the type strain is a circular chromosome of 5,521,203 bp with 57.56% GC content. From 540 Klebsiella strains whose genomes had been publicly available as at 3 March 2015, we identified 21 strains belonging to K. variicola and 8 strains belonging to K. quasipneumoniae based on the genome average nucleotide identities (ANI). All the K. variicola strains, one K. pneumoniae strain and five K. quasipneumoniae strains contained nitrogen-fixing genes. A phylogenomic analysis showed clear species demarcations for these nitrogen-fixing bacteria. In accordance with the key biochemical characteristics of K. variicola, the idnO gene encoding 5-keto-D-gluconate 5-reductase for utilization of 5-keto-D-gluconate and the sorCDFBAME operon for catabolism of L-sorbose were present whereas the rbtRDKT operon for catabolism of adonitol was absent in the genomes of K. variicola strains. Therefore, the genomic analyses supported the ANI-based species delineation; the genome sequence of the K. variicola type strain provides the reference genome for genomic identification of K. variicola, which is a nitrogen-fixing species.

  18. Aeromonas punctata derived depolymerase that disrupts the integrity of Klebsiella pneumoniae capsule: optimization of depolymerase production.

    PubMed

    Bansal, Shruti; Soni, Sanjeev Kumar; Harjai, Kusum; Chhibber, Sanjay

    2014-07-01

    Formation of dense, highly hydrated biofilm structures pose a risk for public and environmental health. Extracellular polymeric substances encompassing biofilms offer 1000-fold greater resistance as compared to the planktonic cells. Using enzymes as anti-biofouling agents, will improve penetration of antimicrobials and increase susceptibility of biofilms to components of immune system. The challenge of using enzymes derived from unrelated bacteria for the degradation of capsular matrix of Klebsiella pneumoniae has not been dealt in the past. Thus, statistical optimization was done to enhance depolymerase production by Aeromonas punctata, directed against the exopolysaccharide matrix of Klebsiella pneumoniae B5055, capable of substituting the available phage borne depolymerase enzyme. Optimization via central composite design (CCD) resulted in 16-fold enhancement in depolymerase yield (166.65 µmoles ml(-1)  min(-1) ) over unoptimized medium. Out of the 19 variables, media composition giving maximum expression levels of the enzyme consisted of 1 mg ml(-1) galactose and ammonium chloride, 1.5 mg ml(-1) each of capsular polysaccharide (CPS) and magnesium sulfate. Tryptic peptide analysis of the purified 29 kDa band by Matrix assisted laser desorption ionization-time of flight (MALDI-TOF) showed a high homology with a protein of unknown function from Aeromonas cavaie Ae398. Further improvements in the enzyme can lead to its successful development as prophylactic and/or a therapeutic agent.

  19. Prevalence of ESBL producing Escherichia Coli and Klebsiella species with their co-resistance pattern to antimicrobials.

    PubMed

    Biswas, T; Das, M; Mondal, R; Raj, H J; Mondal, S

    2013-04-01

    Extended spectrum β-lactamase producing bacteria are potential emerging pathogens and continue to be a major challenge in clinical setup worldwide. In the present study an attempt was made to study the prevalence of extended spectrum β-lactamase producing Escherichia coli and Klebsiella species from clinical isolates in a rural tertiary care hospital in West Bengal, India with their antimicrobial susceptibility as well as co-resistance pattern to different antimicrobials. A total of 179 Escherichia coli and 62 Klebsiella isolates recovered from various clinical samples of urine, pus, aural swabs and respiratory secretions (including sputum) for a period of six months were subjected to routine antimicrobial susceptibility testing and also tested for extended spectrum β-lactamase production as per NCCLS recommendations. Extended spectrum β-lactamase was detected in 32.40% of Escherichia coli and 40.32% of Klebsiella species isolates. Urine, pus and respiratory samples were common source of extended spectrum β-lactamase producers and resistance rate of these organisms to third generation cephalosporins were more than 30 to 40%. Co-resistance pattern of these extended spectrum β-lactamase producers to other commonly used antimicrobials were also statistically significant (p≤0.05). From the study it is concluded that indiscriminate use of third generation cephalosporins may be responsible for the selection of extended spectrum β-lactamase producing multidrug resistant strains in hospital setup and amikacin is a reliable drug against them.

  20. Outbreak of NDM-1-Producing Klebsiella pneumoniae Causing Neonatal Infection in a Teaching Hospital in Mainland China

    PubMed Central

    Zhang, XiaoYu; Li, XianPing; Yue, HeJia; Li, PengLing; Liu, YaPing; Cao, Wei; Yao, DongMei; Liu, Li; Zhou, XiaoLan; Zheng, Rong; Bo, Tao

    2015-01-01

    The emergence and spread of bacteria carrying the blaNDM-1 gene has become a worldwide concern. Here, we report eight cases of Klebsiella pneumoniae with blaNDM-1 in the neonatal ward of a teaching hospital in mainland China. Multilocus sequence typing showed that seven isolates were clonally related and confirmed them as sequence type 17 (ST17). One isolate belonged to ST433. These findings suggest continuous spread of blaNDM-1 in mainland China and emphasize the need for intensive surveillance and precautions. PMID:25941224

  1. Outbreak of NDM-1-producing Klebsiella pneumoniae causing neonatal infection in a teaching hospital in mainland China.

    PubMed

    Zhang, XiaoYu; Li, XianPing; Wang, Min; Yue, HeJia; Li, PengLing; Liu, YaPing; Cao, Wei; Yao, DongMei; Liu, Li; Zhou, XiaoLan; Zheng, Rong; Bo, Tao

    2015-07-01

    The emergence and spread of bacteria carrying the bla(NDM-1) gene has become a worldwide concern. Here, we report eight cases of Klebsiella pneumoniae with bla(NDM-1) in the neonatal ward of a teaching hospital in mainland China. Multilocus sequence typing showed that seven isolates were clonally related and confirmed them as sequence type 17 (ST17). One isolate belonged to ST433. These findings suggest continuous spread of bla(NDM-1) in mainland China and emphasize the need for intensive surveillance and precautions.

  2. The diversity of Klebsiella pneumoniae surface polysaccharides

    PubMed Central

    Heinz, Eva; Wyres, Kelly L.; Ellington, Matthew J.; Kowarik, Michael; Holt, Kathryn E.; Thomson, Nicholas R.

    2016-01-01

    Klebsiella pneumoniae is considered an urgent health concern due to the emergence of multi-drug-resistant strains for which vaccination offers a potential remedy. Vaccines based on surface polysaccharides are highly promising but need to address the high diversity of surface-exposed polysaccharides, synthesized as O-antigens (lipopolysaccharide, LPS) and K-antigens (capsule polysaccharide, CPS), present in K. pneumoniae. We present a comprehensive and clinically relevant study of the diversity of O- and K-antigen biosynthesis gene clusters across a global collection of over 500 K. pneumoniae whole-genome sequences and the seroepidemiology of human isolates from different infection types. Our study defines the genetic diversity of O- and K-antigen biosynthesis cluster sequences across this collection, identifying sequences for known serotypes as well as identifying novel LPS and CPS gene clusters found in circulating contemporary isolates. Serotypes O1, O2 and O3 were most prevalent in our sample set, accounting for approximately 80 % of all infections. In contrast, K serotypes showed an order of magnitude higher diversity and differ among infection types. In addition we investigated a potential association of O or K serotypes with phylogenetic lineage, infection type and the presence of known virulence genes. K1 and K2 serotypes, which are associated with hypervirulent K. pneumoniae, were associated with a higher abundance of virulence genes and more diverse O serotypes compared to other common K serotypes. PMID:28348868

  3. Vector promoters used in Klebsiella pneumoniae.

    PubMed

    Jiang, Xiao; Zhu, Chengqian; Lin, Jie; Li, Jingkang; Fu, Shuilin; Gong, Heng

    2016-09-01

    Much effort has been devoted to the metabolic engineering of Klebsiella pneumoniae; however, our knowledge of the actual expression level of promoters used in K. pneumoniae is limited. In this study, the expression levels of three promoters were compared systematically by using the lacZ reporter gene with different carbon sources in K. pneumoniae. The results showed that, although promoters PT5 and Ptac designed for Escherichia coli were functional, PT5 appeared more efficient and the induction/repression ratio of Ptac was decreased extremely in K. pneumoniae. The basal level of Ptac for lacZ expression reached 396.5 U/mg, which was 9.5-fold higher compared with PT5 in LB medium, indicating Ptac can be used as an efficient "constitutive" promoter as well as an efficient induced promoter in K. pneumoniae. In different carbon sources medium, a newly constructed endogenous constitutive Pbud proved to be a stable and weak promoter. On the basis of our data, a set of Pbud and Ptac promoters could meet the broad range (about 1,000 orders of magnitude) of gene expression needed for engineered K. pneumoniae in glycerol-based medium.

  4. Perianal Abscess and Proctitis by Klebsiella pneumoniae.

    PubMed

    Jeong, Woo Shin; Choi, Sung Youn; Jeong, Eun Haeng; Bang, Ki Bae; Park, Seung Sik; Lee, Dae Sung; Park, Dong Il; Jung, Yoon Suk

    2015-01-01

    Klebsiella pneumoniae (K. pneumoniae) can at times cause invasive infections, especially in patients with diabetes mellitus and a history of alcohol abuse. A 61-year-old man with diabetes mellitus and a history of alcohol abuse presented with abdominal and anal pain for two weeks. After admission, he underwent sigmoidoscopy, which revealed multiple ulcerations with yellowish exudate in the rectum and sigmoid colon. The patient was treated with ciprofloxacin and metronidazole. After one week, follow up sigmoidoscopy was performed owing to sustained fever and diarrhea. The lesions were aggravated and seemed webbed in appearance because of damage to the rectal mucosa. Abdominal computed tomography and rectal magnetic resonance imaging were performed, and showed a perianal and perirectal abscess. The patient underwent laparoscopic sigmoid colostomy and perirectal abscess incision and drainage. Extended-spectrum beta-lactamase-producing K. pneumoniae was identified in pus culture. The antibiotics were switched to ertapenem. He improved after surgery and was discharged. K. pneumoniae can cause rapid invasive infection in patients with diabetes and a history of alcohol abuse. We report the first rare case of proctitis and perianal abscess caused by invasive K. pneumoniae infection.

  5. Neutral red-mediated microbial electrosynthesis by Escherichia coli, Klebsiella pneumoniae, and Zymomonas mobilis

    PubMed Central

    Harrington, Timothy D.; Mohamed, Abdelrhman; Tran, Vi N.; Biria, Saeid; Gargouri, Mahmoud; Park, Jeong-Jin; Gang, David R.; Beyenal, Haluk

    2015-01-01

    The aim of this work was to compare the effects of electrosynthesis on different bacterial species. The effects of neutral red-mediated electrosynthesis on the metabolite profiles of three microorganisms: Escherichia coli, Klebsiella pneumoniae, and Zymomonas mobilis, were measured and compared and contrasted. A statistically comprehensive analysis of neutral red-mediated electrosynthesis is presented using the analysis of end-product profiles, current delivered, and changes in cellular protein expression. K. pneumoniae displayed the most dramatic response to electrosynthesis of the three bacteria, producing 93% more ethanol and 76% more lactate vs. control fermentation with no neutral red and no electron delivery. Z. mobilis showed no response to electrosynthesis except elevated acetate titers. Stoichiometric comparison showed that NAD+ reduction by neutral red could not account for changes in metabolites during electrosynthesis. Neutral red-mediated electrosynthesis was shown to have multifarious effects on the three species. PMID:26096579

  6. Phagocytosis and Killing of Carbapenem-Resistant ST258 Klebsiella pneumoniae by Human Neutrophils.

    PubMed

    Kobayashi, Scott D; Porter, Adeline R; Dorward, David W; Brinkworth, Amanda J; Chen, Liang; Kreiswirth, Barry N; DeLeo, Frank R

    2016-05-15

    Carbapenem-resistant Klebsiella pneumoniae strains classified as multilocus sequence type 258 (ST258) are among the most widespread multidrug-resistant hospital-acquired pathogens. Treatment of infections caused by these organisms is difficult, and mortality is high. The basis for the success of ST258, outside of antibiotic resistance, remains incompletely determined. Here we tested the hypothesis that ST258K. pneumoniae has enhanced capacity to circumvent killing by human neutrophils, the primary cellular defense against bacterial infections. There was limited binding and uptake of ST258 by human neutrophils, and correspondingly, there was limited killing of bacteria. On the other hand, transmission electron microscopy revealed that any ingested organisms were degraded readily within neutrophil phagosomes, thus indicating that survival in the neutrophil assays is due to limited phagocytosis, rather than to microbicide resistance after uptake. Our findings suggest that enhancing neutrophil phagocytosis is a potential therapeutic approach for treatment of infection caused by carbapenem-resistant ST258K. pneumoniae.

  7. Neutral red-mediated microbial electrosynthesis by Escherichia coli, Klebsiella pneumoniae, and Zymomonas mobilis.

    PubMed

    Harrington, Timothy D; Mohamed, Abdelrhman; Tran, Vi N; Biria, Saeid; Gargouri, Mahmoud; Park, Jeong-Jin; Gang, David R; Beyenal, Haluk

    2015-11-01

    The aim of this work was to compare the effects of electrosynthesis on different bacterial species. The effects of neutral red-mediated electrosynthesis on the metabolite profiles of three microorganisms: Escherichia coli, Klebsiella pneumoniae, and Zymomonas mobilis, were measured and compared and contrasted. A statistically comprehensive analysis of neutral red-mediated electrosynthesis is presented using the analysis of end-product profiles, current delivered, and changes in cellular protein expression. K. pneumoniae displayed the most dramatic response to electrosynthesis of the three bacteria, producing 93% more ethanol and 76% more lactate vs. control fermentation with no neutral red and no electron delivery. Z. mobilis showed no response to electrosynthesis except elevated acetate titers. Stoichiometric comparison showed that NAD(+) reduction by neutral red could not account for changes in metabolites during electrosynthesis. Neutral red-mediated electrosynthesis was shown to have multifarious effects on the three species.

  8. Tracking a hospital outbreak of carbapenem-resistant Klebsiella pneumoniae with whole-genome sequencing.

    PubMed

    Snitkin, Evan S; Zelazny, Adrian M; Thomas, Pamela J; Stock, Frida; Henderson, David K; Palmore, Tara N; Segre, Julia A

    2012-08-22

    The Gram-negative bacteria Klebsiella pneumoniae is a major cause of nosocomial infections, primarily among immunocompromised patients. The emergence of strains resistant to carbapenems has left few treatment options, making infection containment critical. In 2011, the U.S. National Institutes of Health Clinical Center experienced an outbreak of carbapenem-resistant K. pneumoniae that affected 18 patients, 11 of whom died. Whole-genome sequencing was performed on K. pneumoniae isolates to gain insight into why the outbreak progressed despite early implementation of infection control procedures. Integrated genomic and epidemiological analysis traced the outbreak to three independent transmissions from a single patient who was discharged 3 weeks before the next case became clinically apparent. Additional genomic comparisons provided evidence for unexpected transmission routes, with subsequent mining of epidemiological data pointing to possible explanations for these transmissions. Our analysis demonstrates that integration of genomic and epidemiological data can yield actionable insights and facilitate the control of nosocomial transmission.

  9. Species distribution and antimicrobial susceptibility of gram-negative aerobic bacteria in hospitalized cancer patients

    PubMed Central

    Ashour, Hossam M; El-Sharif, Amany

    2009-01-01

    Background Nosocomial infections pose significant threats to hospitalized patients, especially the immunocompromised ones, such as cancer patients. Methods This study examined the microbial spectrum of gram-negative bacteria in various infection sites in patients with leukemia and solid tumors. The antimicrobial resistance patterns of the isolated bacteria were studied. Results The most frequently isolated gram-negative bacteria were Klebsiella pneumonia (31.2%) followed by Escherichia coli (22.2%). We report the isolation and identification of a number of less-frequent gram negative bacteria (Chromobacterium violacum, Burkholderia cepacia, Kluyvera ascorbata, Stenotrophomonas maltophilia, Yersinia pseudotuberculosis, and Salmonella arizona). Most of the gram-negative isolates from Respiratory Tract Infections (RTI), Gastro-intestinal Tract Infections (GITI), Urinary Tract Infections (UTI), and Bloodstream Infections (BSI) were obtained from leukemic patients. All gram-negative isolates from Skin Infections (SI) were obtained from solid-tumor patients. In both leukemic and solid-tumor patients, gram-negative bacteria causing UTI were mainly Escherichia coli and Klebsiella pneumoniae, while gram-negative bacteria causing RTI were mainly Klebsiella pneumoniae. Escherichia coli was the main gram-negative pathogen causing BSI in solid-tumor patients and GITI in leukemic patients. Isolates of Escherichia coli, Klebsiella, Enterobacter, Pseudomonas, and Acinetobacter species were resistant to most antibiotics tested. There was significant imipenem -resistance in Acinetobacter (40.9%), Pseudomonas (40%), and Enterobacter (22.2%) species, and noticeable imipinem-resistance in Klebsiella (13.9%) and Escherichia coli (8%). Conclusion This is the first study to report the evolution of imipenem-resistant gram-negative strains in Egypt. Mortality rates were higher in cancer patients with nosocomial Pseudomonas infections than any other bacterial infections. Policies restricting

  10. Rhinoscleroma with Pharyngolaryngeal Involvement Caused by Klebsiella ozaenae

    PubMed Central

    Gonzales Zamora, J.; Murali, A. R.

    2016-01-01

    Rhinoscleroma is a chronic, slowly progressive granulomatous bacterial infection that is endemic to the tropical world, namely, Central America and Africa. It is occasionally seen in the United States of America (USA). It predominately affects the nasal mucosa but can also involve the rest of the upper respiratory tract. The well-known causative agent for rhinoscleroma is the bacterium Klebsiella rhinoscleromatis, a subspecies of Klebsiella pneumoniae. However, Klebsiella ozaenae can also, albeit very rarely, cause rhinoscleroma. The diagnosis is confirmed by histopathology examination that shows the characteristic Mikulicz cells, considered pathognomonic for this infection. We report a patient with histologically proven rhinoscleroma with pharyngolaryngeal involvement in whom cultures yielded Klebsiella ozaenae. To the best of our knowledge, only two cases of rhinoscleroma due to Klebsiella ozaenae have been reported in the literature to date. Our case illustrates the importance of recognizing this infection in a nonendemic setting such as the USA. A lack of awareness and a delay in the diagnosis of this disease can lead to complications including upper airway obstruction, physical deformity, and, rarely, sepsis. In addition, it must be remembered that the treatment of rhinoscleroma is challenging and requires a prolonged course of antibiotics to achieve a definite cure and avoid relapses. PMID:27293924

  11. Anti-Biofilm Activity: A Function of Klebsiella pneumoniae Capsular Polysaccharide

    PubMed Central

    Dos Santos Goncalves, Marina; Delattre, Cédric; Balestrino, Damien; Charbonnel, Nicolas; Elboutachfaiti, Redouan; Wadouachi, Anne; Badel, Stéphanie; Bernardi, Thierry; Michaud, Philippe; Forestier, Christiane

    2014-01-01

    Competition and cooperation phenomena occur within highly interactive biofilm communities and several non-biocides molecules produced by microorganisms have been described as impairing biofilm formation. In this study, we investigated the anti-biofilm capacities of an ubiquitous and biofilm producing bacterium, Klebsiella pneumoniae. Cell-free supernatant from K. pneumoniae planktonic cultures showed anti-biofilm effects on most Gram positive bacteria tested but also encompassed some Gram negative bacilli. The anti-biofilm non-bactericidal activity was further investigated on Staphylococcus epidermidis, by determining the biofilm biomass, microscopic observations and agglutination measurement through a magnetic bead-mediated agglutination test. Cell-free extracts from K. pneumoniae biofilm (supernatant and acellular matrix) also showed an influence, although to a lesser extend. Chemical analyses indicated that the active molecule was a high molecular weight polysaccharide composed of five monosaccharides: galactose, glucose, rhamnose, glucuronic acid and glucosamine and the main following sugar linkage residues [→2)-α-l-Rhap-(1→]; [→4)-α-l-Rhap-(1→]; [α-d-Galp-(1→]; [→2,3)-α-d-Galp-(1→]; [→3)-β-d-Galp-(1→] and, [→4)-β-d-GlcAp-(1→]. Characterization of this molecule indicated that this component was more likely capsular polysaccharide (CPS) and precoating of abiotic surfaces with CPS extracts from different serotypes impaired the bacteria-surface interactions. Thus the CPS of Klebsiella would exhibit a pleiotropic activity during biofilm formation, both stimulating the initial adhesion and maturation steps as previously described, but also repelling potential competitors. PMID:24932475

  12. Mapping the Evolution of Hypervirulent Klebsiella pneumoniae

    PubMed Central

    Roe, Chandler C.; Stegger, Marc; Stahlhut, Steen G.; Hansen, Dennis S.; Engelthaler, David M.; Andersen, Paal S.; Driebe, Elizabeth M.; Keim, Paul; Krogfelt, Karen A.

    2015-01-01

    ABSTRACT Highly invasive, community-acquired Klebsiella pneumoniae infections have recently emerged, resulting in pyogenic liver abscesses. These infections are caused by hypervirulent K. pneumoniae (hvKP) isolates primarily of capsule serotype K1 or K2. Hypervirulent K1 isolates belong to clonal complex 23 (CC23), indicating that this clonal lineage has a specific genetic background conferring hypervirulence. Here, we apply whole-genome sequencing to a collection of K. pneumoniae isolates to characterize the phylogenetic background of hvKP isolates with an emphasis on CC23. Most of the hvKP isolates belonged to CC23 and grouped into a distinct monophyletic clade, revealing that CC23 is a unique clonal lineage, clearly distinct from nonhypervirulent strains. Separate phylogenetic analyses of the CC23 isolates indicated that the CC23 lineage evolved recently by clonal expansion from a single common ancestor. Limited grouping according to geographical origin was observed, suggesting that CC23 has spread globally through multiple international transmissions. Conversely, hypervirulent K2 strains clustered in genetically unrelated groups. Strikingly, homologues of a large virulence plasmid were detected in all hvKP clonal lineages, indicating a key role in K. pneumoniae hypervirulence. The plasmid encodes two siderophores, aerobactin and salmochelin, and RmpA (regulator of the mucoid phenotype); all these factors were found to be restricted to hvKP isolates. Genomic comparisons revealed additional factors specifically associated with CC23. These included a distinct variant of a genomic island encoding yersiniabactin, colibactin, and microcin E492. Furthermore, additional novel genomic regions unique to CC23 were revealed which may also be involved in the increased virulence of this important clonal lineage. PMID:26199326

  13. Evidence for a nicotinamide nucleotide transhydrogenase in Klebsiella pneumoniae.

    PubMed

    Fristedt, U; Rydström, J; Persson, B

    1994-02-15

    Bacterial membranes from Klebsiella pneumoniae were investigated for the presence of a nicotinamide nucleotide transhydrogenase activity. Inverted membrane vesicles derived from these cells catalyzed a reduction of NAD+ or 3-acetylpyridine-NAD+ by NADPH, which showed a maximal activity of about 260 nmoles/minute per milligram protein at pH 7-8. In the presence of a protonic uncoupler the specific activity was stimulated about two-fold in this pH range. The presence of detergents did not further increase the specific activity of enzyme. The Klebsiella pneumoniae transhydrogenase activity was sensitive to phenylarsine oxide and palmityl-Coenzyme A, both of which are agents known to inhibit the mammalian enzyme. The Ki-value for palmityl-Coenzyme A with respect to NADPH was about 1.25 microM. Antibodies raised against beef heart transhydrogenase crossreacted with a 54 kD protein in the Klebsiella pneumonia membrane.

  14. Impact of Extended Spectrum Beta-Lactamase Producing Klebsiella pneumoniae Infections in Severely Burned Patients

    DTIC Science & Technology

    2010-09-01

    versus nosocomial Klebsiella pneumoniae bacteremia: clinical features, treatment outcomes, and clinical implication of antimicrobial resistance. J...Impact of Extended Spectrum Beta-Lactamase Producing Klebsiella pneumoniae Infections in Severely Burned Patients Jason W Bennett, MD, MSPH, Janelle...Significantly higher mortality has been demonstrated in patients who suffer severe burns com- plicated by Klebsiella pneumoniae bacteremia. The specific

  15. Killing of Klebsiella pneumoniae by human alveolar macrophages.

    PubMed

    Hickman-Davis, Judy M; O'Reilly, Philip; Davis, Ian C; Peti-Peterdi, Janos; Davis, Glenda; Young, K Randall; Devlin, Robert B; Matalon, Sadis

    2002-05-01

    We investigated putative mechanisms by which human surfactant protein A (SP-A) effects killing of Klebsiella pneumoniae by human alveolar macrophages (AMs) isolated from bronchoalveolar lavagates of patients with transplanted lungs. Coincubation of AMs with human SP-A (25 microg/ml) and Klebsiella resulted in a 68% decrease in total colony forming units by 120 min compared with AMs infected with Klebsiella in the absence of SP-A, and this SP-A-mediated effect was abolished by preincubation with N(G)-monomethyl-L-arginine. Incubation of transplant AMs with SP-A increased intracellular Ca(2+) concentration ([Ca(2+)](i)) by 70% and nitrite and nitrate (NO(x)) production by 45% (from 0.24 +/- 0.02 to 1.3 +/- 0.21 nmol small middle dot 10(6) AMs(-1).h(-1)). Preincubation with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester inhibited the increase in [Ca(2+)](i) and abrogated the SP-A-mediated Klebsiella phagocytosis and killing. In contrast, incubation of AMs from normal volunteers with SP-A decreased both [Ca(2+)](i) and NO(x) production and did not result in killing of Klebsiella. Significant killing of Klebsiella was also seen in a cell-free system by sustained production of peroxynitrite (>1 microM/min) at pH 5 but not at pH 7.4. These findings indicate that SP-A mediates pathogen killing by AMs from transplant lungs by stimulating phagocytosis and production of reactive oxygen-nitrogen intermediates.

  16. Molecular characterization of multidrug-resistant Klebsiella pneumoniae isolates.

    PubMed

    Hou, Xiang-hua; Song, Xiu-yu; Ma, Xiao-bo; Zhang, Shi-yang; Zhang, Jia-qin

    2015-01-01

    Klebsiella pneumoniae is an important cause of healthcare-associated infections worldwide. Selective pressure, the extensive use of antibiotics, and the conjugational transmission of antibiotic resistance genes across bacterial species and genera facilitate the emergence of multidrug-resistant (MDR) K. pneumoniae. Here, we examined the occurrence, phenotypes and genetic features of MDR K. pneumoniae isolated from patients in intensive care units (ICUs) at the First Affiliated Hospital of Xiamen University in Xiamen, China, from January to December 2011. Thirty-eight MDR K. pneumoniae strains were collected. These MDR K. pneumoniae isolates possessed at least seven antibiotic resistance determinants, which contribute to the high-level resistance of these bacteria to aminoglycosides, macrolides, quinolones and β-lactams. Among these isolates, 24 strains were extended-spectrum β-lactamase (ESBL) producers, 2 strains were AmpC producers, and 12 strains were both ESBL and AmpC producers. The 38 MDR isolates also contained class I (28/38) and class II integrons (10/38). All 28 class I-positive isolates contained aacC1, aacC4, orfX, orfX' and aadA1 genes. β-lactam resistance was conferred through bla SHV (22/38), bla TEM (10/38), and bla CTX-M (7/38). The highly conserved bla KPC-2 (37/38) and bla OXA-23(1/38) alleles were responsible for carbapenem resistance, and a gyrAsite mutation (27/38) and the plasmid-mediated qnrB gene (13/38) were responsible for quinolone resistance. Repetitive-sequence-based PCR (REP-PCR) fingerprinting of these MDR strains revealed the presence of five groups and sixteen patterns. The MDR strains from unrelated groups showed different drug resistance patterns; however, some homologous strains also showed different drug resistance profiles. Therefore, REP-PCR-based analyses can provide information to evaluate the epidemic status of nosocomial infection caused by MDR K. pneumoniae; however, this test lacks the power to discriminate some

  17. The use of bacteria in conformance control - Initial studies

    SciTech Connect

    MacLeod, F.A.; Lappin-Scott, H.M.; Cusack, F.; Costerton, J.W.

    1988-05-01

    Bacteria respond to nutrient starvation by reducing in size to form ultramicrobacteria (UMB) less than 0.3 ..mu..m in diameter. Work in the authors' laboratory has established that two bacteria, Klebsiella pneumoniae and a Psuedomonas species, isolated from oilwell waters decreased in size when deprived of nutrients. Subsequent restoration of nutrients resulted in the resuscitation of the UMB and they returned to normal size. When injected into model rock cores, the UMB penetrated deeper than the full-sized bacteria. Higher counts of bacteria and carbohydrate production were found around the core inlet with the full-sized bacteria. However, the UMB were located throughout the entire core. This work demonstrates that UMB may provide a new selective plugging technique by virtue of their superior penetration properties throughout solid matrices.

  18. The K1 beta-lactamase of Klebsiella pneumoniae.

    PubMed Central

    Joris, B; De Meester, F; Galleni, M; Frère, J M; Van Beeumen, J

    1987-01-01

    beta-Lactamase K1 was purified from Klebsiella pneumoniae SC10436. It is very similar to the enzyme produced by Klebsiella aerogenes 1082E and described by Emanuel, Gagnon & Waley [Biochem. J. (1986) 234, 343-347]. An active-site peptide was isolated after labelling of the enzyme with tritiated beta-iodopenicillanate. A cysteine residue was found just before the active-site serine residue. This result could explain the properties of the enzyme after modification by thiol-blocking reagents. The sequence of the active-site peptide clearly established the enzyme as a class A beta-lactamase. PMID:3307765

  19. Acute renal failure caused by Klebsiella pneumoniae pyelonephritis.

    PubMed

    Creyghton, W M; Lobatto, S; Weening, J J

    2001-11-01

    We report a 34-year-old male patient without prior medical history who presented with acute renal failure due to acute bacterial pyelonephritis. Both blood and urine cultures grew Klebsiella pneumoniae. Although a kidney biopsy revealed extensive necrosis and no viable glomeruli, renal function recovered to near normal after intermittent hemodialysis and antibiotic therapy. We believe that it is important to include this entity in the differential diagnosis of acute renal failure since proper diagnosis and treatment is essential for recovery of renal function. Furthermore, we would like to draw attention to Klebsiella pneumoniae as an important potential pathogen in such cases, in addition to Escherichia coli.

  20. Epidemiological typing of Klebsiella pneumoniae by pyrolysis mass spectrometry.

    PubMed

    Jackson, R M; Heginbothom, M L; Magee, J T

    1997-01-01

    Thirteen isolates of ceftazidime-resistant Klebsiella pneumoniae from a suspected cross-infection outbreak involving patients on an intensive care unit and a haematology ward were examined in pyrolysis-mass spectrometry (Py-MS), along with eight concurrent non-outbreak-associated clinical isolates of klebsiellae as controls. Py-MS showed tight clustering of the suspected outbreak isolates, suggesting cross-infection with a single strain. Non-outbreak isolates were clearly distinct from one another and from the outbreak strain. The results confirm that Py-MS is a powerful tool for rapid strain comparison in investigations of cross-infection incidents.

  1. Spectroscopic investigations of the binding mechanisms between antimicrobial peptides and membrane models of Pseudomonas aeruginosa and Klebsiella pneumoniae.

    PubMed

    Chai, Hanbo; Allen, William E; Hicks, Rickey P

    2014-08-01

    CD spectroscopy was used to investigate the interactions of a series of synthetic AMPs with LPS isolated from Pseudomonas aeruginosa and Klebsiella pneumoniae, as well as with various phospholipids to better approximate the chemical composition of the membranes of these two strains of Gram-negative bacteria. This investigation was conducted in order to probe how the contributions of key physicochemical properties of an AMP vary in different regions of the membranes of these two bacteria. The conclusions from this study are as follows. (1) The binding interactions between the AMP and the membranes are defined by the complementarity of delocalization of positive charge density of the basic amino side chains (i.e., electrostatics), molecular flexibility of the peptide backbone, and overall hydrophobicity. (2) The binding interactions of these AMPs to LPS seem to be predominantly with the lipid A region of the LPS. (3) Incorporation of phospholipids into the LPS containing SUVs resulted in dramatic changes in the conformational equilibrium of the bound AMPs. (4) For the LPS-phospholipid models of Pseudomonas aeruginosa, delocalization of the side chain positive charge plays a major role in determining the number of conformers that contribute to the binding conformational equilibrium. This relationship was not observed for the models of the outer and inner membranes of Klebsiella pneumoniae.

  2. [Electron microscopic study of pathogenic bacteria on environmental objects].

    PubMed

    Pavlova, I B; Lenchenko, E M

    1998-01-01

    The morphological picture of different bacteria (Salmonella typhimurium, Proteus vulgaris, Klebsiella pneumoniae, Pseudomonas aeruginosa, Yersinia enterocolitica O3, Y.pseudotuberculosis 1, Y.frederiksenii, Y.intermedia, Y.kristensenii) on environmental objects was studied with the use of scanning electron microscopy (SEM). Bacteria adhered to the surface of pieces of fodder, egg shell, cabbage leaves and form microcolonies, whose morphology was similar to colonies, grown on nutrient media. The cells produced extracellular substances, seen in SEM as integuments. These integuments were gourd to protect the population from the action of unfavorable factors.

  3. Magnetic Bacteria.

    ERIC Educational Resources Information Center

    Nelson, Jane Bray; Nelson, Jim

    1992-01-01

    Describes the history of Richard Blakemore's discovery of magnetotaxic organisms. Discusses possible reasons why the magnetic response in bacteria developed. Proposes research experiments integrating biology and physics in which students investigate problems using cultures of magnetotaxic organisms. (MDH)

  4. DUOX2 promotes the elimination of the Klebsiella pneumoniae strain K5 from T24 cells through the reactive oxygen species pathway.

    PubMed

    Lu, Huixia; Wu, Qi; Yang, Huijun

    2015-08-01

    Dual oxidase 2 (DUOX2) plays a major role in host defense in intestinal and airway epithelial cells through the reactive oxygen species (ROS) pathway. Klebsiella pneumoniae is a uropathogen that causes urinary tract infections. It is not known whether DUOX2 plays a role in host defense in bladder cancer epithelial cells. It is also not known whether Klebsiella pneumoniae invades T24 human bladder carcinoma cells and whether DUOX2 plays a role in eliminating the Klebsiella pneumoniae strain K5 through the ROS pathway in T24 cells. Thus, in the present study, we aimed to investigate the infectious capability of the Klebsiella pneumoniae K5 strain and the immunity-promoting capability of DUOX2 in T24 cells. We quantified the number of viable intracellular bacteria using the plate count method. DUOX2 expression was evaluated by western blot analysis and reverse transcription-quantitative PCR (RT-qPCR) following treatment with or without multiple cytokines, phorbol 12-myristate 13-acetate (PMA), muramyl dipeptide (MDP), N-acetylmuramyl-D-alanyl-D-isoglutamine (MDP-DD), H2O2 inhibitor, catalase (CAT), the nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) oxidase inhibitor, diphenyleneiodonium (DPI), or siRNA targeting DUOX2 (siDUOX2). The levels of ROS in the T24 cells infected with the K5 strain were examined following treatment with DPI, CAT or siDUOX2. Our results revealed that DUOX2 expression increased and the number of viable intracellular bacteria decreased in the T24 cells following infection with the K4 bacteria. Treatment with the cytokines and MDP and PMA also induced DUOX2 expression and decreased the number of viable intracellular bacteria. The levels of ROS also increased following treatment with the cytokines and MDP and PMA. However, when the cells were treated with the inhibitors (DPI or CAT), these effects were all reversed. Our data demonstrated that DUOX2 played an important role in innate immunity against bacterial cytoinvasion through the

  5. 21 CFR 866.3340 - Klebsiella spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Klebsiella spp. serological reagents. 866.3340 Section 866.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3340...

  6. 21 CFR 866.3340 - Klebsiella spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Klebsiella spp. serological reagents. 866.3340 Section 866.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3340...

  7. 21 CFR 866.3340 - Klebsiella spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Klebsiella spp. serological reagents. 866.3340 Section 866.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3340...

  8. 21 CFR 866.3340 - Klebsiella spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Klebsiella spp. serological reagents. 866.3340 Section 866.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3340...

  9. 21 CFR 866.3340 - Klebsiella spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Klebsiella spp. serological reagents. 866.3340 Section 866.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3340...

  10. Klebsiella pneumoniae in Gastrointestinal Tract and Pyogenic Liver Abscess

    PubMed Central

    Lin, Yi-Tsung; Lin, Jung-Chung; Chen, Te-Li; Yeh, Kuo-Ming; Chang, Feng-Yee; Chuang, Han-Chuan; Wu, Hau-Shin; Tseng, Chih-Peng; Siu, L. Kristopher

    2012-01-01

    To determine the role of gastrointestinal carriage in Klebsiella pneumoniae liver abscess, we studied 43 patients. Bacterial isolates from liver and fecal samples from 10 patients with this condition and 7 healthy carriers showed identical serotypes and genotypes with the same virulence. This finding indicated that gastrointestinal carriage is a predisposing factor for liver abscess. PMID:22840473

  11. Significance of Fecal Coliform-Positive Klebsiella1

    PubMed Central

    Bagley, Susan T.; Seidler, Ramon J.

    1977-01-01

    A total of 191 Klebsiella pneumoniae isolates of human clinical, bovine mastitis, and a wide variety of environmental sources were tested for fecal coliform (FC) response with the membrane filtration and most probable number techniques. Twenty-seven Escherichia coli cultures of human clinical and environmental origins were also tested. Eighty-five percent (49/58) of known pathogenic K. pneumoniae were FC positive, compared with 16% (19/120) of the environmental strains. E. coli results indicated 93% (13/14) of the clinical and 85% (11/13) of the environmental strains as FC positive. There was no significant difference in the incidence of FC-positive cultures between pathogenic Klebsiella and E. coli. pH measurements of K. pneumoniae and E. coli cultures growing in m-FC broth at 44.5°C revealed three distinct pH ranges correlating with colony morphology. β-Galactosidase assays of Klebsiella and E. coli cultures at 44.5°C indicated all were able to hydrolyze lactose, even if they were FC negative by the membrane filtration or most probable number techniques. The FC response pattern appears stable in K. pneumoniae. Three pathogenic cultures showed no change in FC responses after 270 generations of growth in sterile pulp mill effluent. Since K. pneumoniae is carried in the gastrointestinal tract of humans and animals and 85% of the tested pathogenic strains were FC positive, the isolation of FC-positive Klebsiella organisms from the environment would indicate their fecal or clinical origin or both. The added fact that K. pneumoniae is an opportunistic pathogen of increasing importance makes the occurrence of FC-positive environmental Klebsiella, particularly in large numbers, a potential human and animal health hazard. PMID:18086

  12. The IκB family member Bcl-3 coordinates the pulmonary defense against Klebsiella pneumoniae infection.

    PubMed

    Pène, Frédéric; Paun, Andrea; Sønder, Søren Ulrik; Rikhi, Nimisha; Wang, Hongshan; Claudio, Estefania; Siebenlist, Ulrich

    2011-02-15

    Bcl-3 is an atypical member of the IκB family that has the potential to positively or negatively modulate nuclear NF-κB activity in a context-dependent manner. Bcl-3's biologic impact is complex and includes roles in tumorigenesis and diverse immune responses, including innate immunity. Bcl-3 may mediate LPS tolerance, suppressing cytokine production, but it also seems to contribute to defense against select systemic bacterial challenges. However, the potential role of Bcl-3 in organ-specific host defense against bacteria has not been addressed. In this study, we investigated the relevance of Bcl-3 in a lung challenge with the Gram-negative pathogen Klebsiella pneumoniae. In contrast to wild-type mice, Bcl-3-deficient mice exhibited significantly increased susceptibility toward K. pneumoniae pneumonia. The mutant mice showed increased lung damage marked by neutrophilic alveolar consolidation, and they failed to clear bacteria in lungs, which correlated with increased bacteremic dissemination. Loss of Bcl-3 incurred a dramatic cytokine imbalance in the lungs, which was characterized by higher levels of IL-10 and a near total absence of IFN-γ. Moreover, Bcl-3-deficient mice displayed increased lung production of the neutrophil-attracting chemokines CXCL-1 and CXCL-2. Alveolar macrophages and neutrophils are important to antibacterial lung defense. In vitro stimulation of Bcl-3-deficient alveolar macrophages with LPS or heat-killed K. pneumoniae recapitulated the increase in IL-10 production, and Bcl-3-deficient neutrophils were impaired in intracellular bacterial killing. These findings suggest that Bcl-3 is critically involved in lung defense against Gram-negative bacteria, modulating functions of several cells to facilitate efficient clearance of bacteria.

  13. Rapid Induction of High-Level Carbapenem Resistance in Heteroresistant KPC-Producing Klebsiella pneumoniae

    PubMed Central

    Adams-Sapper, Sheila; Nolen, Shantell; Donzelli, Grace Fox; Lal, Mallika; Chen, Kunihiko; Justo da Silva, Livia Helena; Moreira, Beatriz M.

    2015-01-01

    Enterobacteriaceae strains producing the Klebsiella pneumoniae carbapenemase (KPC) have disseminated worldwide, causing an urgent threat to public health. KPC-producing strains often exhibit low-level carbapenem resistance, which may be missed by automated clinical detection systems. In this study, eight Klebsiella pneumoniae strains with heterogeneous resistance to imipenem were used to elucidate the factors leading from imipenem susceptibility to high-level resistance as defined by clinical laboratory testing standards. Time-kill analysis with an inoculum as low as 3 × 106 CFU/ml and concentrations of imipenem 8- and 16-fold higher than the MIC resulted in the initial killing of 99.9% of the population. However, full recovery of the population occurred by 20 h of incubation in the same drug concentrations. Population profiles showed that recovery was mediated by a heteroresistant subpopulation at a frequency of 2 × 10−7 to 3 × 10−6. Samples selected 2 h after exposure to imipenem were as susceptible as the unexposed parental strain and produced the major outer membrane porin OmpK36. However, between 4 to 8 h after exposure, OmpK36 became absent, and the imipenem MIC increased at least 32-fold. Individual colonies isolated from cultures after 20 h of exposure revealed both susceptible and resistant subpopulations. Once induced, however, the high-level imipenem resistance was maintained, and OmpK36 remained unexpressed even without continued carbapenem exposure. This study demonstrates the essential coordination between blaKPC and ompK36 expression mediating high-level imipenem resistance from a population of bacteria that initially exhibits a carbapenem-susceptibility phenotype. PMID:25801565

  14. Effect of subinihibitory and inhibitory concentrations of Plectranthus amboinicus (Lour.) Spreng essential oil on Klebsiella pneumoniae.

    PubMed

    Gonçalves, Thially Braga; Braga, Milena Aguiar; de Oliveira, Francisco F M; Santiago, Gilvandete M P; Carvalho, Cibele B M; Brito e Cabral, Paula; de Melo Santiago, Thiago; Sousa, Jeanlex S; Barros, Eduardo Bedê; do Nascimento, Ronaldo Ferreira; Nagao-Dias, Aparecida T

    2012-08-15

    We evaluated the antimicrobial activity and some mechanisms used by subinhibitory and inhibitory concentrations of the essential oil, obtained from leaves of Plectranthus amboinicus, against a standard strain of Klebsiella pneumoniae and 5 multiresistant clinical isolates of the bacteria. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC), the rate of kill and the pH sensitivity of the essential oil were determined by microdilution tests performed in 96-well plates. Subinhibitory and inhibitory concentrations of the essential oil were tested in order to check its action on K. pneumoniae membrane permeability, capsule expression, urease activity and cell morphology. The MIC and MBC of the essential oil were 0.09±0.01%. A complete inhibition of the bacterial growth was observed after 2 h of incubation with twice the MIC of the essential oil. A better MIC was found when neutral or alkaline pH broth was used. Alteration in membrane permeability was found by the increase of crystal violet uptake when the bacteria were incubated with twice the MIC levels of the essential oil. The urease activity could be prevented when all the subinhibitory concentrations were tested in comparison to the untreated group (p<0.001). Alteration of the bacterial morphology besides inhibition of the capsule expression was verified by atomic force microscopy, and Anthony's stain method, respectively. Our data allow us to conclude that the essential oil of P. amboinicus can be a good candidate for future research.

  15. The metabolic flux regulation of Klebsiella pneumoniae based on quorum sensing system

    PubMed Central

    Sun, Shujing; Zhang, Haiyang; Lu, Shuyi; Lai, Chunfen; Liu, Huijun; Zhu, Hu

    2016-01-01

    Quorum-sensing (QS) systems exist universally in bacteria to regulate multiple biological functions. Klebsiella pneumoniae, an industrially important bacterium that produces bio-based chemicals such as 2,3-butanediol and acetoin, can secrete a furanosyl borate diester (AI-2) as the signalling molecule mediating a QS system, which plays a key regulatory role in the biosynthesis of secondary metabolites. In this study, the molecular regulation and metabolic functions of a QS system in K. pneumoniae were investigated. The results showed that after the disruption of AI-2-mediated QS by the knockout of luxS, the production of acetoin, ethanol and acetic acid were relatively lower in the K. pneumoniae mutant than in the wild type bacteria. However, 2,3-butanediol production was increased by 23.8% and reached 54.93 g/L. The observed enhancement may be attributed to the improvement of the catalytic activity of 2,3-butanediol dehydrogenase (BDH) in transforming acetoin to 2,3-butanediol. This possibility is consistent with the RT-PCR-verified increase in the transcriptional level of budC, which encodes BDH. These results also demonstrated that the physiological metabolism of K. pneumoniae was adversely affected by a QS system. This effect was reversed through the addition of synthetic AI-2. This study provides the basis for a QS-modulated metabolic engineering study of K. pneumoniae. PMID:27924940

  16. N-Acyl Homoserine Lactone Production by Klebsiella pneumoniae Isolated from Human Tongue Surface

    PubMed Central

    Yin, Wai-Fong; Purmal, Kathiravan; Chin, Shenyang; Chan, Xin-Yue; Koh, Chong-Lek; Sam, Choon-Kook; Chan, Kok-Gan

    2012-01-01

    Bacteria communicate by producing quorum sensing molecules called autoinducers, which include autoinducer-1, an N-hexanoyl homoserine lactone (AHL), and autoinducer-2. Bacteria present in the human oral cavity have been shown to produce autoinducer-2, but not AHL. Here, we report the isolation of two AHL-producing Klebsiella pneumoniae strains from the posterior dorsal surface of the tongue of a healthy individual. Spent culture supernatant extracts from K. pneumoniae activated the biosensors Agrobacterium tumefaciens NTL4(pZLR4) and Escherichia coli [pSB401], suggesting the presence of both long and short chain AHLs. High resolution mass spectrometry analyses of these extracts confirmed that both K. pneumoniae isolates produced N-octanoylhomoserine lactone and N-3-dodecanoyl-l-homoserine lactone. To the best of our knowledge, this is the first report of the isolation of K. pneumoniae from the posterior dorsal surface of the human tongue and the production of these AHLs by this bacterium. PMID:22737019

  17. Insights on Klebsiella pneumoniae Biofilms Assembled on Different Surfaces Using Phenotypic and Genotypic Approaches.

    PubMed

    Bandeira, Maria; Borges, Vítor; Gomes, João P; Duarte, Aida; Jordao, Luisa

    2017-04-03

    Klebsiella pneumoniae is a prominent etiological agent of healthcare associated infections (HAIs). In this context, multidrug-resistant and biofilm-producing bacteria are of special public health concern due to the difficulties associated with treatment of human infections and eradication from hospital environments. Here, in order to study the impact of medical devices-associated materials on the biofilm dynamics, we performed biofilm phenotypic analyses through a classic and a new scanning electron microscopy (SEM) technique for three multidrug-resistant K. pneumoniae isolates growing on polystyrene and silicone. We also applied whole-genome sequencing (WGS) to search for genetic clues underlying biofilm phenotypic differences. We found major differences in the extracellular polymeric substances (EPS) content among the three strains, which were further corroborated by in-depth EPS composition analysis. WGS analysis revealed a high nucleotide similarity within the core-genome, but relevant differences in the accessory genome that may account for the detected biofilm phenotypic dissimilarities, such as genes already associated with biofilm formation in other pathogenic bacteria (e.g., genes coding haemogglutinins and haemolysins). These data reinforce that the research efforts to defeat bacterial biofilms should take into account that their dynamics may be contingent on the medical devices-associated materials.

  18. Methanotrophic bacteria.

    PubMed Central

    Hanson, R S; Hanson, T E

    1996-01-01

    Methane-utilizing bacteria (methanotrophs) are a diverse group of gram-negative bacteria that are related to other members of the Proteobacteria. These bacteria are classified into three groups based on the pathways used for assimilation of formaldehyde, the major source of cell carbon, and other physiological and morphological features. The type I and type X methanotrophs are found within the gamma subdivision of the Proteobacteria and employ the ribulose monophosphate pathway for formaldehyde assimilation, whereas type II methanotrophs, which employ the serine pathway for formaldehyde assimilation, form a coherent cluster within the beta subdivision of the Proteobacteria. Methanotrophic bacteria are ubiquitous. The growth of type II bacteria appears to be favored in environments that contain relatively high levels of methane, low levels of dissolved oxygen, and limiting concentrations of combined nitrogen and/or copper. Type I methanotrophs appear to be dominant in environments in which methane is limiting and combined nitrogen and copper levels are relatively high. These bacteria serve as biofilters for the oxidation of methane produced in anaerobic environments, and when oxygen is present in soils, atmospheric methane is oxidized. Their activities in nature are greatly influenced by agricultural practices and other human activities. Recent evidence indicates that naturally occurring, uncultured methanotrophs represent new genera. Methanotrophs that are capable of oxidizing methane at atmospheric levels exhibit methane oxidation kinetics different from those of methanotrophs available in pure cultures. A limited number of methanotrophs have the genetic capacity to synthesize a soluble methane monooxygenase which catalyzes the rapid oxidation of environmental pollutants including trichloroethylene. PMID:8801441

  19. Antibody-free detection of infectious bacteria using quantum dots-based barcode assay.

    PubMed

    Cihalova, Kristyna; Hegerova, Dagmar; Jimenez, Ana Maria; Milosavljevic, Vedran; Kudr, Jiri; Skalickova, Sylvie; Hynek, David; Kopel, Pavel; Vaculovicova, Marketa; Adam, Vojtech

    2017-02-05

    Staphylococcus aureus, methicillin-resistant Staphylococcus aureus and Klebsiella pneumoniae are the most representative bacteria causing infectious diseases. Due to the increased application of antibiotics, the bacterial resistance is growing causing severe complications. Therefore, a sensitive determination of these pathogens is crucial for effective treatment. The aim of this study was to design an effective method for multiplex detection of Staphylococcus aureus, methicillin-resistant Staphylococcus aureus and Klebsiella pneumoniae taking advantage from properties of magnetic particles as well as fluorescent nanoparticles (quantum dots). The method was able to detect as low concentrations of bacteria as 10(2) CFU/mL using the bacteria-specific genes (fnbA, mecA and wcaG).

  20. Comparative effects of carbapenems on bacterial load and host immune response in a Klebsiella pneumoniae murine pneumonia model.

    PubMed

    Hilliard, Jamese J; Melton, John L; Hall, LeRoy; Abbanat, Darren; Fernandez, Jeffrey; Ward, Christine K; Bunting, Rachel A; Barron, A; Lynch, A Simon; Flamm, Robert K

    2011-02-01

    Doripenem is a carbapenem with potent broad-spectrum activity against Gram-negative pathogens, including antibiotic-resistant Enterobacteriaceae. As the incidence of extended-spectrum β-lactamase (ESBL)-producing Gram-negative bacilli is increasing, it was of interest to examine the in vivo comparative efficacy of doripenem, imipenem, and meropenem against a Klebsiella pneumoniae isolate expressing the TEM-26 ESBL enzyme. In a murine lethal lower respiratory infection model, doripenem reduced the Klebsiella lung burden by 2 log(10) CFU/g lung tissue over the first 48 h of the infection. Treatment of mice with meropenem or imipenem yielded reductions of approximately 1.5 log(10) CFU/g during this time period. Seven days postinfection, Klebsiella titers in the lungs of treated mice decreased an additional 2 log(10) CFU/g relative to those in the lungs of untreated control animals. Lipopolysaccharide (LPS) endotoxin release assays indicated that 6 h postinfection, meropenem- and imipenem-treated animals had 10-fold more endotoxin in lung homogenates and sera than doripenem-treated mice. Following doripenem treatment, the maximum endotoxin release postinfection (6 h) was 53,000 endotoxin units (EU)/ml, which was 2.7- and 6-fold lower than imipenem or meropenem-treated animals, respectively. While the levels of several proinflammatory cytokines increased in both the lungs and sera following intranasal K. pneumoniae inoculation, doripenem treatment, but not meropenem or imipenem treatment, resulted in significantly increased interleukin 6 levels in lung homogenates relative to those in lung homogenates of untreated controls, which may contribute to enhanced neutrophil killing of bacteria in the lung. Histological examination of tissue sections indicated less overall inflammation and tissue damage in doripenem-treated mice, consistent with improved antibacterial efficacy, reduced LPS endotoxin release, and the observed cytokine induction profile.

  1. Bioflocculant produced by Klebsiella sp. MYC and its application in the treatment of oil-field produced water

    NASA Astrophysics Data System (ADS)

    Yue, Lixi; Ma, Chunling; Chi, Zhenming

    2006-10-01

    Seventy-nine strains of bioflocculant-producing bacteria were isolated from 3 activated sludge samples. Among them, strain MYC was found to have the highest and stable flocculating rate for both kaolin clay suspension and oil-field produced water. The bacterial strain was identified as Klebsiella sp. MYC according to its morphological and biochemical characteristics and 16SrDNA sequence. The optimal medium for bioflocculant production by this bacterial strain was composed of cane sugar 20gL-1 KH2PO4 2g L-1, K2HPO45gL-1, (NH4)2SO4 0.2gL-1, urea 0.5 gL-1 and yeast extract 0.5 gL-1, the initial pH being 5.5. When the suspension of kaolin clay was treated with 0.5% of Klebsiella sp. MYC culture broth, the flocculating rate reached more than 90.0% in the presence of 500mgL1 CaCl2, while the flocculating rate for oil-field produced water was near 80.0% in a pH range of 7.0-9.0 with the separation of oil and suspended particles from the oil-field produced water under similar conditions. The environment-friendly nature of the bioflocculant and high flocculating rate of the strain make the bioflocculant produced by Klebsiella sp. MYC an attractive bioflocculant in oil-field produced water treatment.

  2. Enterobacter aerogenes Hormaeche and Edwards 1960 (Approved Lists 1980) and Klebsiella mobilis Bascomb et al. 1971 (Approved Lists 1980) share the same nomenclatural type (ATCC 13048) on the Approved Lists and are homotypic synonyms, with consequences for the name Klebsiella mobilis Bascomb et al. 1971 (Approved Lists 1980).

    PubMed

    Tindall, B J; Sutton, G; Garrity, G M

    2017-02-01

    Enterobacter aerogenes Hormaeche and Edwards 1960 (Approved Lists 1980) and Klebsiella mobilis Bascomb et al. 1971 (Approved Lists 1980) were placed on the Approved Lists of Bacterial Names and were based on the same nomenclatural type, ATCC 13048. Consequently they are to be treated as homotypic synonyms. However, the names of homotypic synonyms at the rank of species normally are based on the same epithet. Examination of the Rules of the International Code of Nomenclature of Bacteria in force at the time indicates that the epithet mobilis in Klebsiella mobilis Bascomb et al. 1971 (Approved Lists 1980) was illegitimate at the time the Approved Lists were published and according to the Rules of the current International Code of Nomenclature of Prokaryotes continues to be illegitimate.

  3. Lipopolysaccharide-specific bacteriophage for Klebsiella pneumoniae C3.

    PubMed Central

    Tomás, J M; Jofre, J T

    1985-01-01

    Bacteriophage FC3-1 is one of several specific bacteriophages of Klebsiella pneumoniae C3 isolated in our laboratory. Unlike receptors for other Klebsiella phages, the bacteriophage FC3-1 receptor was shown to be lipopolysaccharide, specifically the polysaccharide fraction (O-antigen and core region). We concluded that capsular polysaccharide, outer membrane proteins, and lipid A were not involved in phage binding. Mutants resistant to this phage were isolated and were found to be devoid of lipopolysaccharide O-antigen by several criteria but to contain capsular material serologically identical to that of the wild type. The polysaccharide fraction was concluded to be the primary phage receptor, indicating that it is available to the phage. Images PMID:3888963

  4. Klebsiella pneumoniae necrotizing fasciitis in a Latin American male.

    PubMed

    Persichino, Jon; Tran, Richard; Sutjita, Made; Kim, Daniel

    2012-11-01

    Necrotizing fasciitis, caused by Klebsiella pneumoniae, is a rare and life-threatening bacterial infection. Most documented cases have been reported from Asia, particularly associated with diabetes mellitus. The prevalence of this infection in the USA is rare, especially among persons of non-Asian descent and those without travel to Asia. We report a case of disseminated necrotizing fasciitis, caused by K. pneumoniae, in a Latin American male with diabetes mellitus. Given our review of the literature, this is the only case report, to our knowledge, of a Latin American patient with Klebsiella necrotizing fasciitis in the USA. This case may reflect the geographical spread and emergence of K. pneumoniae infection in the USA. Clinicians need to be aware of the possible relationship between this organism and necrotizing fasciitis in persons of Latin American descent with diabetes mellitus.

  5. Isolation and characterization of Klebsiella pneumoniae unencapsulated mutants

    SciTech Connect

    Benedi, V.J.; Ciurana, B.; Tomas, J.M.

    1989-01-01

    Klebsiella pneumoniae mutants were obtained after UV irradiation and negative selection with anticapsular serum. Unencapsulation, rather than expression of a structurally altered capsule, was found in the mutants. The mutant strains showed no alterations in their outer membrane proteins and lipopolysaccharide, and a great similarity with the wild type in the properties tested (serum resistance, antimicrobial sensitivity, and lipopolysaccharide-specific bacteriophage sensitivity), with the exception of a higher cell surface hydrophobicity and resistance to bacteriophage FC3-9.

  6. Draft Genome Sequence of Klebsiella pneumoniae AWD5

    PubMed Central

    Rajkumari, Jina; Singha, L. Paikhomba

    2017-01-01

    ABSTRACT Here, we report the draft genome sequence of Klebsiella pneumoniae strain AWD5, isolated from an automobile workshop in India. The de novo assembly resulted in a 4,807,409 bp genome containing 25 rRNA genes, 81 tRNAs, and 4,636 coding sequences (CDS). It carries important genes for polyaromatic hydrocarbon degradation and benzoate degradation. PMID:28153891

  7. Gram-Negative Bacteria Produce Membrane Vesicles Which Are Capable of Killing Other Bacteria

    PubMed Central

    Li, Zusheng; Clarke, Anthony J.; Beveridge, Terry J.

    1998-01-01

    Naturally produced membrane vesicles (MVs), isolated from 15 strains of gram-negative bacteria (Citrobacter, Enterobacter, Escherichia, Klebsiella, Morganella, Proteus, Salmonella, and Shigella strains), lysed many gram-positive (including Mycobacterium) and gram-negative cultures. Peptidoglycan zymograms suggested that MVs contained peptidoglycan hydrolases, and electron microscopy revealed that the murein sacculi were digested, confirming a previous modus operandi (J. L. Kadurugamuwa and T. J. Beveridge, J. Bacteriol. 174:2767–2774, 1996). MV-sensitive bacteria possessed A1α, A4α, A1γ, A2α, and A4γ peptidoglycan chemotypes, whereas A3α, A3β, A3γ, A4β, B1α, and B1β chemotypes were not affected. Pseudomonas aeruginosa PAO1 vesicles possessed the most lytic activity. PMID:9765585

  8. Bacteria Counter

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Science Applications, Inc.'s ATP Photometer makes a rapid and accurate count of the bacteria in a body fluid sample. Instrument provides information on the presence and quantity of bacteria by measuring the amount of light emitted by the reaction between two substances. Substances are ATP adenosine triphosphate and luciferase. The reactants are applied to a human body sample and the ATP Photometer observes the intensity of the light emitted displaying its findings in a numerical output. Total time lapse is usually less than 10 minutes, which represents a significant time savings in comparison of other techniques. Other applications are measuring organisms in fresh and ocean waters, determining bacterial contamination of foodstuffs, biological process control in the beverage industry, and in assay of activated sewage sludge.

  9. Antimicrobial resistance temporal trend of Klebsiella pneumoniae isolated from blood

    PubMed Central

    Gavriliu, LC; Benea, OE; Benea, S

    2016-01-01

    Background. According to the European Antimicrobial Resistance Surveillance Network, Romania reports an increasing number of resistant Klebsiella pneumoniae strains from invasive infections every year. Material and Method. We analyzed the antimicrobial susceptibility of Klebsiella pneumoniae strains isolated from blood in 2010 and 2015 in “Matei Bals” National Institute of Infectious Diseases, in order to identify any significant changes in the last five years. Results. We identified 18 strains in 2010 and 37 strains in 2015. Although the resistance to aminopenicillin-betalactamase inhibitors association, piperacillin-tazobactam, third generation cephalosporins, fluoroquinolones, gentamicin, amikacin and the combined resistance decreased between these two time frames, this evolution was statistically non-significant. The same was noticed for the increased resistance rates to carbapenems. Conclusions. Antimicrobial resistance of Klebsiella pneumoniae may become a major problem for the public health and the hospital-acquired infections control. Therefore, it needs further monitoring and efforts must be made in order to limit the increase of the resistance. PMID:27928448

  10. Klebsiella sp. strain C2A isolated from olive oil mill waste is able to tolerate and degrade tannic acid in very high concentrations.

    PubMed

    Pepi, Milva; Cappelli, Serena; Hachicho, Nancy; Perra, Guido; Renzi, Monia; Tarabelli, Alessandro; Altieri, Roberto; Esposito, Alessandro; Focardi, Silvano E; Heipieper, Hermann J

    2013-06-01

    Four bacterial strains capable of growing in the presence of tannic acid as sole carbon and energy source were isolated from olive mill waste mixtures. 16S rRNA gene sequencing assigned them to the genus Klebsiella. The most efficient strain, Klebsiella sp. strain C2A, was able to degrade 3.5 g L(-1) tannic acid within 35 h with synthesizing gallic acid as main product. The capability of Klebsiella sp. strain C2A to produce tannase was evidenced at high concentrations of tannic acid up to 50 g L(-1) . The bacteria adapted to the toxicity of tannic acids by an increase in the membrane lipid fatty acids degree of saturation, especially in the presence of concentrations higher than 20 g L(-1) . The highly tolerant and adaptable bacterial strain characterized in this study could be used in bioremediation processes of wastes rich in polyphenols such as those derived from olive mills, winery or tanneries.

  11. Evolution of β-lactams resistance in Gram-negative bacteria in Tunisia.

    PubMed

    Chouchani, Chedly; Marrakchi, Rim; El Salabi, Allaaeddin

    2011-08-01

    Antimicrobial resistance is a major health problem worldwide, but marked variations in the resistance profiles of bacterial pathogens are found between countries and in different patient settings. In Tunisia, the strikingly high prevalence of resistance of bacteria to penicillins and cephalorosporins drugs including fourth generation in clinical isolates of Gram negative bacteria has been reported. During 30 years, the emerging problem of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolates is substantial, and some unique enzymes have been found. Recently, evidence that Gram-negative bacteria are resistant to nearly all available antimicrobial agents, including carbapenems, have emerged.

  12. Distribution of CTX-M group I and group III β-lactamases produced by Escherichia coli and klebsiella pneumoniae in Lahore, Pakistan.

    PubMed

    Abrar, Samyyia; Vajeeha, Ayesha; Ul-Ain, Noor; Riaz, Saba

    2017-02-01

    Extended-spectrum-lactamases (ESBLs) of the CTX-M type is worrisome issue in many countries of the world from past decade. But little is known about CTX-M beta-lactamase producing bacteria in Pakistan. Therefore, this study was carried out to investigate the distribution of CTX-M beta-lactamase producing E. coli and Klebsiella pneumoniae using phenotypic and molecular techniques. A total of 638 E. coli and 338 Klebsiella pneumoniae were isolated from patients attending two hospitals and one diagnostic Centre in Pakistan during 2013-2015. ESBL production was screened by double disc synergism, combination disc (cefotaxime and ceftazidime with clavulanic acid) and E-test. These strains were further characterized by PCR (CTX-M I, CTX-M III) and sequencing. After ribotyping of strains accession numbers were obtained. These isolates were highly resistant to cephalosporins, ceftazidime, cefotaxime, aztreonam, and cefuroxime but susceptible to carbapenems, sulfzone, amikacin and tazocin. Multiple antibiotic resistances index (MAR) revealed that 51% of E. coli strains fell in the range of 0.61-0.7 and 39% of Klebsiella pneumoniae strains fell in the range of 0.71-0.8. 64% Double disc synergism (DDS), 76.4% combination disc (CD), 74% E-test showed ESBL positivity in strains. In E. coli ESBL genes blaCTX-M-I and blaCTX-M-III were detected in 212 (72.1%) and 25 (8.5%) respectively. In Klebsiella pneumoniae ESBL genes blaCTX-M-I and blaCTX-M-III were detected in 89 (82.4%) and 10 (9.2%). Combination of both genes blaCTX-M-I and blaCTX-M-III were found in 16 (5.4%) of E. coli strains and 5 (4.6%) of Klebsiella pneumoniae strains. Sequencing revealed that CTXM-15 was predominately present in the CTX-M-I group. The prevalence of ESBL producing E. coli and Klebsiella pneumoniae isolates was high and the majority of them positive for blaCTX-M-I as compared to blaCTX-M-III. These findings highlight the need to further investigate the epidemiology of other CTX-M beta

  13. Endocarditis Due to Rare and Fastidious Bacteria

    PubMed Central

    Brouqui, P.; Raoult, D.

    2001-01-01

    The etiologic diagnosis of infective endocarditis is easily made in the presence of continuous bacteremia with gram-positive cocci. However, the blood culture may contain a bacterium rarely associated with endocarditis, such as Lactobacillus spp., Klebsiella spp., or nontoxigenic Corynebacterium, Salmonella, Gemella, Campylobacter, Aeromonas, Yersinia, Nocardia, Pasteurella, Listeria, or Erysipelothrix spp., that requires further investigation to establish the relationship with endocarditis, or the blood culture may be uninformative despite a supportive clinical evaluation. In the latter case, the etiologic agents are either fastidious extracellular or intracellular bacteria. Fastidious extracellular bacteria such as Abiotrophia, HACEK group bacteria, Clostridium, Brucella, Legionella, Mycobacterium, and Bartonella spp. need supplemented media, prolonged incubation time, and special culture conditions. Intracellular bacteria such as Coxiella burnetii cannot be isolated routinely. The two most prevalent etiologic agents of culture-negative endocarditis are C. burnetti and Bartonella spp. Their diagnosis is usually carried out serologically. A systemic pathologic examination of excised heart valves including periodic acid-Schiff (PAS) staining and molecular methods has allowed the identification of Whipple's bacillus endocarditis. Pathologic examination of the valve using special staining, such as Warthin-Starry, Gimenez, and PAS, and broad-spectrum PCR should be performed systematically when no etiologic diagnosis is evident through routine laboratory evaluation. PMID:11148009

  14. Modeling Meropenem Treatment, Alone and in Combination with Daptomycin, for KPC-Producing Klebsiella pneumoniae Strains with Unusually Low Carbapenem MICs

    PubMed Central

    Gagetti, P.; Pasteran, F.; Martinez, M. P.; Fatouraei, M.; Gu, J.; Fernandez, R.; Paz, L.; Rose, W. E.

    2016-01-01

    Klebsiella pneumoniae strains producing K. pneumoniae carbapenemase (KPC) cause serious infections in debilitated and immunocompromised patients and are associated with prolonged hospital stays and increased mortality rates. Daptomycin is a lipopeptide used against Staphylococcus aureus infection and considered inactive against Gram-negative bacteria. We investigated the effectiveness of a daptomycin-meropenem combination by synergy kill curve and a pharmacokinetic/pharmacodynamic model. The combination may represent a novel therapeutic strategy against infections caused by KPC-producing K. pneumoniae strains. PMID:27216067

  15. [Microbiological characteristics and detection of capsular forms of bacteria of the intestinal group in confectionery produced at the candy-chocolate factories].

    PubMed

    Kuvaeva, I B; Troshina, M Iu

    1988-01-01

    Five types of confectionery and its semifinished products were investigated for contamination with Klebsiella, mesophilic aerobic and elective anaerobic, coliform bacteria, E. coli, etc. after a long-term storage. E. coli and St. aureus were not detected after inoculation on 1 g of the product; mold fungi were identified only in singular samples, their level did not exceed 20 CFU/g; the level of mesophilic aerobic and elective anaerobic bacteria varied from several hundreds to 3000-5500 CFU/g; coliform bacteria were identified in the amounts from 11 to 100 CFU/g. The identification of coliform bacteria has evidenced the presence of Enterobacter aerogenes and Kl. pneumoniae in the products investigated. Klebsiella were detected in 28-30% of the samples analyzed, their level did not exceed 100 CFU/g. The authors have proved the necessity of microbiological control of starting material, semifinished and finished confectionery products for the above bacteria.

  16. Bacteria in surface infections of neonates.

    PubMed

    Ghosh, S; Chatterjee, B D; Chakraborty, C K; Chakravarty, A; Khatua, S P

    1995-04-01

    A bacteriological work on surface infections was done among live births (study group I) and neonates admitted in hospital (study group II). Out of 134 cases of conjunctivitis in group I Gram-negative bacilli predominated (48.5%) with Escherichia coli accounting for 29 (14.9%) cases, Klebsiella species 15 (11.2%) cases, Citrobacter freundii 3 (2.2%) cases, Pseudomons aeruginosa 18 (13.4%) cases and Aeromonas hydrophila 3 (2.2%) amongst pure isolates (73.9%). Gonococcus was noted in 2 (1.5%) cases. In group II, 41.7% were Staphylococcus aureus in pure growth (75%), compared to only 9.0% in group I. Skin infections were caused by both Staphylococcus aureus and Staphylococcus epidermidis. Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were the principal insolates from umbilical sepsis. Pseudomonas aeruginosa was isolated as pure growth from local site of noma neonatorum. Anaerobic cultures were negative in all except in 2 cases of umbilical sepsis with tetanus neonatorum revealing Clostridium tetani which however proved to be non-toxigenic. Blood cultures were positive in 4 out of 14 cases bearing 50% correlation with bacteria from surface infections. A source study established partial correlation with the cases of pseudomonas conjunctivitis. Phage typing of Staphylococcus aureus and biochemical typing failed to detect any definite marker of clinical entities, except that the skin infections were caused by group III phages predominantly (65.0%).

  17. Assessment of the In Vitro Activity of Ceftazidime-Avibactam against Multidrug-Resistant Klebsiella spp. Collected in the INFORM Global Surveillance Study, 2012 to 2014

    PubMed Central

    Hackel, Meredith; Hoban, Daryl J.; Biedenbach, Douglas J.; Bouchillon, Samuel K.; de Jonge, Boudewijn L. M.; Stone, Gregory G.

    2016-01-01

    Increasing resistance in Gram-negative bacilli, including Klebsiella spp., has reduced the utility of broad-spectrum cephalosporins. Avibactam, a novel non-β-lactam β-lactamase inhibitor, protects β-lactams from hydrolysis by Gram-negative bacteria that produce extended-spectrum β-lactamases (ESBLs) and serine carbapenemases, including Ambler class A and/or class C and some class D enzymes. In this analysis, we report the in vitro activity of ceftazidime-avibactam and comparators against multidrug-resistant (MDR) Klebsiella spp. from the 2012-2014 INFORM surveillance study. Isolates collected from 176 sites were sent to a central laboratory for confirmatory identification and tested for susceptibility to ceftazidime-avibactam and comparator agents, including ceftazidime alone. A total of 2,821 of 10,998 (25.7%) Klebsiella species isolates were classified as MDR, based on resistance to three or more classes of antimicrobials. Among the MDR isolates, 99.4% had an ESBL screen-positive phenotype, and 27.4% were not susceptible to meropenem as an example of a carbapenem. Ceftazidime-avibactam was highly active against MDR isolates, including ESBL-positive and serine carbapenemase-producing isolates, with MIC50/90 values of 0.5/2 μg/ml and 96.6% of all MDR isolates and ESBL-positive MDR isolates inhibited at the FDA breakpoint (MIC value of ≤8 μg/ml). Ceftazidime-avibactam did not inhibit isolates producing class B enzymes (metallo-β-lactamases) either alone or in combination with other enzymes. These in vitro results support the continued investigation of ceftazidime-avibactam for the treatment of MDR Klebsiella species infections. PMID:27216054

  18. Extended-Spectrum β-Lactamase (ESBL)-Producing Klebsiella pneumoniae in Bulk Tank Milk from Dairy Farms in Indonesia.

    PubMed

    Sudarwanto, Mirnawati; Akineden, Ömer; Odenthal, Sabrina; Gross, Madeleine; Usleber, Ewald

    2015-07-01

    Bulk tank milk from 80 dairy farms located in the West Java Region of Indonesia was analyzed for the presence of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. Isolates from seven dairy farms were ESBL positive, and all were identified as Klebsiella pneumoniae. The isolates showed ESBL-characteristic antibiotic resistance patterns. Further analysis revealed that all K. pneumoniae isolates harbored the blaSHV gene, and two isolates were additionally positive for the blaTEM-1 and blaCTX-M-15 genes. Isolates from different farms were clonally diverse according to macrorestriction analysis. The results indicate that the relatively high frequency of ESBL-producing K. pneumoniae in bulk tank milk implies the risk that milk is both a source of local exposure and a vector contributing to the supraregional spread of antibiotic-resistant bacteria by trade.

  19. First Report of bla CTX-M-15-Type ESBL-Producing Klebsiella pneumoniae in Wild Migratory Birds in Pakistan.

    PubMed

    Raza, Shahbaz; Mohsin, Mashkoor; Madni, Waqas Ahmed; Sarwar, Fatima; Saqib, Muhammad; Aslam, Bilal

    2017-01-11

    We investigated wild migratory birds faecal swabs for extended-spectrum β-lactamases-producing Klebsiella pneumoniae (ESBL-K. pneumoniae) from wetland habitats in Pakistan. ESBL-K. pneumoniae were analysed for MDR phenotype, ESBL genotype and genetic diversity. A total of 13 (8.6%) ESBL-K. pneumoniae were recovered. Of these, 8 (61%) isolates were MDR. DNA sequencing confirmed bla CTX-M-15 as the dominant ESBL genotype. BOX-PCR fingerprints showed most of the isolates are unrelated. This study is the first to report the wildlife contamination of CTX-M-15-producing K. pneumoniae in Pakistan. Due to long-range migration, these birds could be responsible for trans-boundary spread of multidrug-resistant bacteria.

  20. Population Screening Using Sewage Reveals Pan-Resistant Bacteria in Hospital and Community Samples

    PubMed Central

    Mileguir, Fernando; Azar, Roberto; Smollan, Gill; Belausov, Natasha; Rahav, Galia; Shamiss, Ari; Mendelson, Ella; Keller, Nathan

    2016-01-01

    The presence of pan-resistant bacteria worldwide possesses a threat to global health. It is difficult to evaluate the extent of carriage of resistant bacteria in the population. Sewage sampling is a possible way to monitor populations. We evaluated the presence of pan-resistant bacteria in Israeli sewage collected from all over Israel, by modifying the pour plate method for heterotrophic plate count technique using commercial selective agar plates. This method enables convenient and fast sewage sampling and detection. We found that sewage in Israel contains multiple pan-resistant bacteria including carbapenemase resistant Enterobacteriacae carrying blaKPC and blaNDM-1, MRSA and VRE. blaKPC carrying Klebsiella pneumonia and Enterobacter cloacae were the most common Enterobacteriacae drug resistant bacteria found in the sewage locations we sampled. Klebsiella pneumonia, Enterobacter spp., Escherichia coli and Citrobacter spp. were the 4 main CRE isolated from Israeli sewage and also from clinical samples in our clinical microbiology laboratory. Hospitals and Community sewage had similar percentage of positive samplings for blaKPC and blaNDM-1. VRE was found to be more abundant in sewage in Israel than MRSA but there were more locations positive for MRSA and VRE bacteria in Hospital sewage than in the Community. Therefore, our upgrade of the pour plate method for heterotrophic plate count technique using commercial selective agar plates can be a useful tool for routine screening and monitoring of the population for pan-resistant bacteria using sewage. PMID:27780222

  1. Antibiofilm efficacy of silver nanoparticles against biofilm of extended spectrum β-lactamase isolates of Escherichia coli and Klebsiella pneumoniae

    NASA Astrophysics Data System (ADS)

    Ansari, Mohammad Azam; Khan, Haris M.; Khan, Aijaz A.; Cameotra, Swaranjit Singh; Pal, Ruchita

    2014-10-01

    The ability of bacteria to develop antibiotic resistance and colonize abiotic surfaces by forming biofilms is a major cause of medical implant-associated infections and results in prolonged hospitalization periods and patient mortality. Different approaches have been used for preventing biofilm-related infections in health care settings. Many of these methods have their own demerits that include chemical-based complications; emergent antibiotic-resistant strains, and so on. Silver nanoparticles (AgNPs) are renowned for their influential antimicrobial activity. We demonstrate the biofilm formation by extended spectrum β-lactamases-producing Escherichia coli and Klebsiella spp. by direct visualization applying tissue culture plate, tube, and Congo red agar methods. Double fluorescent staining for confocal laser scanning microscopy (CLSM) consisted of propidium iodide staining to detect bacterial cells and concanavalin A-fluorescein isothiocyanate staining to detect the exopolysaccharides matrix were used. Scanning electron microscopy observations clearly indicate that AgNPs reduced the surface coverage by E. coli and Klebsiella spp. thus prevent the biofilm formations. Double-staining technique using CLSM provides the visual evidence that AgNPs arrested the bacterial growth and prevent the exopolysaccharides formation. The AgNPs-coated surfaces effectively restricted biofilm formation of the tested bacteria. In our study, we could demonstrate the complete antibiofilm activity AgNPs at a concentration as low as 50 μg/ml. Our findings suggested that AgNPs can be exploited towards the development of potential antibacterial coatings for various biomedical and environmental applications. These formulations can be used for the treatment of drug-resistant bacterial infections caused by biofilms, at much lower nanosilver loading with higher efficiency.

  2. Inhibitory potential of Buffalo (Bubalus bubalis) colostrum immunoglobulin G on Klebsiella pneumoniae.

    PubMed

    L S, Mamatha Bhanu; Nishimura, S-I; H S, Aparna

    2016-07-01

    The unique components of colostrum like free oligosaccharides and glycoconjugates are known to offer resistance to enzymatic digestion in the gastrointestinal tract and have the ability to inhibit the localized adherence of enteropathogens to the digestive tract of the neonates. In this context, we have evaluated the in vitro effect of buffalo colostrum immunoglobulin G on human pathogen Klebsiella pneumoniae, a predominant multidrug resistant pathogen associated with nasocomial infections. The investigation revealed growth inhibitory potential of immunoglobulin G in a dose dependent manner supported by scanning electron microscopic studies. The N-glycan enriched fraction of immunoglobulin G after PNGase treatment was found more effective, comparable to ampicillin than native immunoglobulin G supporting the fact that colostrum derived oligosaccharides is crucial and act as ideal substrates for undesirable and pathogenic bacteria. The MALDI TOF/TOF analysis confirmed the glycostructures of abundant N-glycans of immunoglobulin G exerting antibacterial activity. The proteomic analysis revealed variations between control and treated cells and expression of chemotaxis-CheY protein (14kDa) was evidenced in response to immunoglobulin G treatment. Hence, it would be interesting to investigate the mode of inhibition of multidrug-resistant K. pneumoniae by buffalo colostrum immunoglobulin G with the identification of a newly expressed signalling protein.

  3. Preliminary investigation of a mice model of Klebsiella pneumoniae subsp. ozaenae induced pneumonia.

    PubMed

    Renois, Fanny; Jacques, Jérôme; Guillard, Thomas; Moret, Hélène; Pluot, Michel; Andreoletti, Laurent; de Champs, Christophe

    2011-11-01

    In the present study, we comparatively assessed the pathophysiological mechanisms developed during lung infection of BALB/C female mice infected by an original wild type Klebsiella pneumoniae subsp. ozaenae strain (CH137) or by a referent subspecies K. pneumoniae. subsp. pneumoniae strain (ATCC10031). The mice infected with 2.10⁶ CFU K. p. subsp. pneumoniae (n = 10) showed transient signs of infection and all of them recovered. All of those infected with 1.10⁶ CFU K. p. subsp. ozaenae (n = 10) developed pneumonia within 24 h and died between 48 and 72 h. Few macrophages, numerous polymorphonuclear cells and lymphocytes were observed in their lungs in opposite to K. p. subsp. pneumoniae. In bronchoalveolar lavage, a significant increase in MIP-2, IL-6, KC and MCP-1 levels was only observed in K. p. subsp. ozaenae infected mice whereas high levels of TNF-α were evidenced with the two subspecies. Our findings indicated a lethal effect of a wild type K. p. subsp. ozaenae strain by acute pneumonia reflecting an insufficient alveolar macrophage response. This model might be of a major interest to comparatively explore the pathogenicity of K. p. subsp ozaenae strains and to further explore the physiopathological mechanisms of gram-negative bacteria induced human pneumonia.

  4. Therapeutic potential of bacteriophage in treating Klebsiella pneumoniae B5055-mediated lobar pneumonia in mice.

    PubMed

    Chhibber, Sanjay; Kaur, Sandeep; Kumari, Seema

    2008-12-01

    Klebsiella pneumoniae causes infections in humans especially in immunocompromised patients. About 80 % of nosocomial infections caused by K. pneumoniae are due to multidrug-resistant strains. The emergence of antibiotic-resistant bacterial strains necessitates the exploration of alternative antibacterial therapies, which led our group to study the ability of bacterial viruses (known as bacteriophages or simply phages) to treat mice challenged with K. pneumoniae. Phage SS specific for K. pneumoniae B5055 was isolated and characterized, and its potential as a therapeutic agent was evaluated in an experimental model of K. pneumoniae-mediated lobar pneumonia in mice. Mice were challenged by intranasal (i.n.) inoculation with bacteria (10(8) c.f.u. ml(-1)). A single intraperitoneal injection of 10(10) p.f.u. ml(-1) phage administered immediately after i.n. challenge was sufficient to rescue 100 % of animals from K. pneumoniae-mediated respiratory infections. Administration of the phage preparation 3 h prior to i.n. bacterial challenge provided significant protection in infected mice, while even 6 h delay of phage administration after the induction of infection rendered the phage treatment ineffective. The results of this study therefore suggest that the timing of starting the phage therapy after initiation of infection significantly contributes towards the success of the treatment.

  5. Emergence of Klebsiella pneumoniae clinical isolates producing KPC-2 carbapenemase in Cuba

    PubMed Central

    Quiñones, D; Hart, M; Espinosa, F; Garcia, S; Carmona, Y; Ghosh, S; Urushibara, N; Kawaguchiya, M; Kobayashi, N

    2014-01-01

    The emergence of Klebsiella pneumoniae producing carbapenemase (KPC) has now become a global concern. As a part of a nationwide multicentre surveillance study in Cuba, three K. pneumoniae clinical isolates resistant to carbapenems were detected for a 1-month period (September to October 2011). PCR and sequence analysis revealed that the three strains harboured blaKPC-2. They showed resistance or intermediate susceptibility to expanded-spectrum cephalosporins, other β-lactams, a β-lactam/β-lactamase inhibitor combination, and gentamicin. Two strains were susceptible only to colistin, whereas the other strain showing colistin resistance was susceptible to fluoroquinolones. These blaKPC-2-positive K. pneumoniae strains were classified into ST1271 (CC29), a novel clone harbouring blaKPC-2, and were revealed to be genetically identical by PCR-based DNA fingerprinting. The three patients infected with the KPC-producing K. pneumoniae had common risk factors, and had no overseas travel experience outside Cuba, suggesting local acquisition of the resistant pathogen. This is the first report of a KPC-producing K. pneumoniae in Cuba. Although detection of KPC in Enterobacteriaceae is still rare in Cuba, our finding indicated that KPC-producing bacteria are a global concern and highlighted the need to identify these microorganisms in clinical laboratories. PMID:25356357

  6. Biofilms from Klebsiella pneumoniae: Matrix Polysaccharide Structure and Interactions with Antimicrobial Peptides

    PubMed Central

    Benincasa, Monica; Lagatolla, Cristina; Dolzani, Lucilla; Milan, Annalisa; Pacor, Sabrina; Liut, Gianfranco; Tossi, Alessandro; Cescutti, Paola; Rizzo, Roberto

    2016-01-01

    Biofilm matrices of two Klebsiella pneumoniae clinical isolates, KpTs101 and KpTs113, were investigated for their polysaccharide composition and protective effects against antimicrobial peptides. Both strains were good biofilm producers, with KpTs113 forming flocs with very low adhesive properties to supports. Matrix exopolysaccharides were isolated and their monosaccharide composition and glycosidic linkage types were defined. KpTs101 polysaccharide is neutral and composed only of galactose, in both pyranose and furanose ring configurations. Conversely, KpTs113 polysaccharide is anionic due to glucuronic acid units, and also contains glucose and mannose residues. The susceptibility of the two strains to two bovine cathelicidin antimicrobial peptides, BMAP-27 and Bac7(1–35), was assessed using both planktonic cultures and biofilms. Biofilm matrices exerted a relevant protection against both antimicrobials, which act with quite different mechanisms. Similar protection was also detected when antimicrobial peptides were tested against planktonic bacteria in the presence of the polysaccharides extracted from KpTs101 and KpTs113 biofilms, suggesting sequestering adduct formation with antimicrobials. Circular dichroism experiments on BMAP-27 in the presence of increasing amounts of either polysaccharide confirmed their ability to interact with the peptide and induce an α-helical conformation. PMID:27681920

  7. Carbapenemase-producing Klebsiella pneumoniae in the Czech Republic in 2011.

    PubMed

    Hrabák, J; Papagiannitsis, C C; Študentová, V; Jakubu, V; Fridrichová, M; Zemlickova, H

    2013-11-07

    Carbapenemase-producing Enterobacteriaceae and Pseudomonas spp. are increasingly reported in many countries all over the world. Due to the resistance of those bacteria to almost all antibiotics (e.g.beta-lactams, aminoglycosides, fluoroquinolones),treatment options are seriously limited. In the Czech Republic, the incidence of carbapenemase-producing Enterobacteriaceae seems to be low, restricted to only three cases detected between 2009 and 2010.Here, we describe molecular typing of 15 carbapenemase-producing Klebsiella pneumoniae isolates identified in the Czech Republic during 2011. Five VIM-1-producing isolates belonging to sequence type (ST)11 and one VIM-4-producing isolate of ST1029 have been detected. blaVIM-1 and blaVIM-4 as a part of class 1 integrons were chromosomally located or carried by a plasmid belonging to A/C replicon type (blaVIM-4). KPC-3-producing isolates of ST512, recovered from six patients, caused an outbreak. Three more isolates producing KPC-2 enzyme belonged to ST258. Both blaKPCgenes were part of the Tn4401a transposon carried on plasmids of the pKpQIL type. The isolates were resistant to all antibiotics tested except colistin and/or gentamicin.Four of these 15 strains were recovered from patients repatriated to the Czech Republic from Greece and Italy. This is the first report of outbreaks caused by carbapenemase-producing Enterobacteriaceae in the Czech Republic.

  8. Part of respiratory nitrate reductase of Klebsiella aerogenes is intimately associated with the peptidoglycan.

    PubMed

    Abraham, P R; Wientjes, F B; Nanninga, N; Van't Riet, J

    1987-02-01

    Lysozyme digestion and sonication of sodium dodecyl sulfate (SDS)-purified Klebsiella aerogenes murein sacculi resulted in the quantitative release of both subunits of nitrate reductase, as well as a number of other cytoplasmic membrane polypeptides (5.2%, by weight, of the total membrane proteins). Similar results were obtained after lysozyme digestion of SDS-prepared peptidoglycan fragments, which excluded the phenomenon of simple trapping of the polypeptides by the surrounding peptidoglycan matrix. About 28% of membrane-bound nitrate reductase appears to be tightly associated with the peptidoglycan. Additional evidence for this association was demonstrated by positive immunogold labeling of SDS-murein sacculi and thin sections of plasmolyzed bacteria. Qualitative amino acid analysis of trypsin-treated sacculi, a tryptic product of holo-nitrate reductase, and amino- and carboxypeptidase digests of both nitrate reductase subunits indicated the possible existence of a terminal anchoring peptide containing the following amino acids: (Gly)n, Trp, Ser, Pro, Ile, Leu, Phe, Cys, Tyr, Asp, and Lys.

  9. Biofilms from Klebsiella pneumoniae: Matrix Polysaccharide Structure and Interactions with Antimicrobial Peptides.

    PubMed

    Benincasa, Monica; Lagatolla, Cristina; Dolzani, Lucilla; Milan, Annalisa; Pacor, Sabrina; Liut, Gianfranco; Tossi, Alessandro; Cescutti, Paola; Rizzo, Roberto

    2016-08-10

    Biofilm matrices of two Klebsiella pneumoniae clinical isolates, KpTs101 and KpTs113, were investigated for their polysaccharide composition and protective effects against antimicrobial peptides. Both strains were good biofilm producers, with KpTs113 forming flocs with very low adhesive properties to supports. Matrix exopolysaccharides were isolated and their monosaccharide composition and glycosidic linkage types were defined. KpTs101 polysaccharide is neutral and composed only of galactose, in both pyranose and furanose ring configurations. Conversely, KpTs113 polysaccharide is anionic due to glucuronic acid units, and also contains glucose and mannose residues. The susceptibility of the two strains to two bovine cathelicidin antimicrobial peptides, BMAP-27 and Bac7(1-35), was assessed using both planktonic cultures and biofilms. Biofilm matrices exerted a relevant protection against both antimicrobials, which act with quite different mechanisms. Similar protection was also detected when antimicrobial peptides were tested against planktonic bacteria in the presence of the polysaccharides extracted from KpTs101 and KpTs113 biofilms, suggesting sequestering adduct formation with antimicrobials. Circular dichroism experiments on BMAP-27 in the presence of increasing amounts of either polysaccharide confirmed their ability to interact with the peptide and induce an α-helical conformation.

  10. Inhibition of Klebsiella pneumoniae DnaB helicase by the flavonol galangin.

    PubMed

    Chen, Cheng-Chieh; Huang, Cheng-Yang

    2011-01-01

    Klebsiella pneumoniae is a ubiquitous opportunistic pathogen that colonizes at the mucosal surfaces in humans and causes severe diseases. Many clinical strains of K. pneumoniae are highly resistant to antibiotics. Here, we used fluorescence quenching to show that the flavonols galangin, myricetin, quercetin, and kaempferol, bearing different numbers of hydroxyl substituent on the aromatic rings, may inhibit dNTP binding of the primary replicative DnaB helicase of K. pneumoniae (KpDnaB), an essential component of the cellular replication machinery critical for bacterial survival. The binding affinity of KpDnaB to dNTPs varies in the following order: dCTP ~ dGTP > dTTP > dATP. Addition of 10 μM galangin significantly decreased the binding ability of KpDnaB to dATP, whereas the binding affinity of KpDnaB to dGTP that was almost unaffected. Our analyses suggest that these flavonol compounds may be used in the development of new antibiotics that target K. pneumoniae and other bacteria.

  11. Chemical composition and antibacterial activity of Lavandula coronopifolia essential oil against antibiotic-resistant bacteria.

    PubMed

    Ait Said, L; Zahlane, K; Ghalbane, I; El Messoussi, S; Romane, A; Cavaleiro, C; Salgueiro, L

    2015-01-01

    The aim of this study was to analyse the composition of the essential oil (EO) of Lavandula coronopifolia from Morocco and to evaluate its in vitro antibacterial activity against antibiotic-resistant bacteria isolated from clinical infections. The antimicrobial activity was assessed by a broth micro-well dilution method using multiresistant clinical isolates of 11 pathogenic bacteria: Klebsiella pneumoniae subsp. pneumoniae, Klebsiella ornithinolytica, Escherichia coli, Enterobacter cloacae, Enterobacter aerogenes, Providencia rettgeri, Citrobacter freundii, Hafnia alvei, Salmonella spp., Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus. The main compounds of the oil were carvacrol (48.9%), E-caryophyllene (10.8%) and caryophyllene oxide (7.7%). The oil showed activity against all tested strains with minimal inhibitory concentration (MIC) values ranging between 1% and 4%. For most of the strains, the MIC value was equivalent to the minimal bactericidal concentration value, indicating a clear bactericidal effect of L. coronopifolia EO.

  12. Intrathecal administration of colistin for meningitis due to New Delhi metallo-β-lactamase 1(NDM-1)-producing Klebsiella pneumoniae.

    PubMed

    Inamasu, Joji; Ishikawa, Kiyohito; Oheda, Motoki; Nakae, Shunsuke; Hirose, Yuichi; Yoshida, Shunji

    2016-03-01

    Infection by bacteria carrying New Delhi metallo-β-lactamase 1 (NDM-1) is becoming a global health problem. We report a case of meningitis caused by NDM-1-producing Klebsiella pneumoniae, for which intrathecal administration of colistin was curative. A previously healthy 38-year-old Japanese man, who lived in Hyderabad, India, suddenly collapsed and was brought to a local hospital. He was diagnosed with subarachnoid hemorrhage and underwent emergency surgery which included partial skull removal. Approximately 1 month after surgery, he was repatriated to Japan and was admitted to our institution with information that he had been treated for multi-drug resistant Acinetobacter infection with colistin. A week after admission, he developed aspiration pneumonia due to NDM-1-producing K. pneumoniae, which was successfully treated by intravenous (IV) administration of colistin. Subsequently, he underwent a surgical procedure to repair his skull defect. He developed high-grade fever and altered mental status on postoperative day 2. NDM-1-producing K. pneumoniae was identified in the cerebrospinal fluid, establishing the diagnosis of meningitis. Although IV colistin was only partially effective, intrathecal colistin (10 mg daily by lumbar puncture for 14 days) successfully eradicated the meningitis. Because of economic globalization, NDM-1-producing bacteria may be brought to Japan by those who are repatriated after sustaining critical illnesses and being treated in foreign countries. This report may provide useful information on the treatment of central nervous system infection by NDM-1-producing bacteria.

  13. Effect of a Metalloantibiotic Produced by Pseudomonas aeruginosa on Klebsiella pneumoniae Carbapenemase (KPC)-producing K. pneumoniae.

    PubMed

    Kerbauy, Gilselena; Vivan, Ana C P; Simões, Glenda C; Simionato, Ane S; Pelisson, Marsileni; Vespero, Eliana C; Costa, Silvia F; Andrade, Celia G T de J; Barbieri, Daiane M; Mello, João C P; Morey, Alexandre T; Yamauchi, Lucy M; Yamada-Ogatta, Sueli F; de Oliveira, Admilton G; Andrade, Galdino

    2016-01-01

    Multidrug-resistant organisms (MDRO) are a great problem in hospitals, where thousands of people are infected daily, with the occurrence of high mortality rates, especially in infections caused by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-producing Kpn). The challenge is to find new compounds that can control KPC producing-Kpn infections. The aim of this study was to evaluate the antibiotic activity of the F3d fraction produced by the Pseudomonas aeruginosa LV strain against clinical isolates of KPC-producing Kpn. The results showed that the minimum inhibitory concentration of F3d (62.5 µg mL(-1)), containing an organic metallic compound, killed planktonic cells of KPC-producing Kpn strains after 30 min of incubation. At the same concentration, this fraction also showed an inhibitory effect against biofilm of these bacteria after 24 h of incubation. Treatment with the F3d fraction caused pronounced morphological alterations in both planktonic and biofilm cells of the bacteria. The inhibitory effect of the F3d fraction seems to be more selective for the bacteria than the host cells, indicating its potential in the development of new drugs for the treatment of infections caused by KPC-producing Kpn and other MDRO.

  14. ECOLOGICAL FACTORS INFLUENCING THE RELATIONSHIPS BETWEEN KLEBSIELLA AND SHIGELLA IN MIXED CULTURE.

    PubMed

    HENTGES, D J; FULTON, M

    1964-03-01

    Hentges, David J. (Loyola University, Chicago, Ill.), and MacDonald Fulton. Ecological factors influencing the relationships between Klebsiella and Shigella in mixed cultures. J. Bacteriol. 87:527-535. 1964.-Viable-cell counts of Shigella flexneri and Klebsiella (Aerobacter aerogenes) in pure and mixed culture were made during growth under predetermined conditions of temperature, pH, oxygen supply, and nutrient supply. In pure culture, environmental changes had marked effects on the Shigella populations. Klebsiella populations were not affected except at 44 C or when aerated; under these conditions, the populations were smaller. In nonaerated mixed culture, under different conditions of temperature, pH, and nutrient supply, Klebsiella interfered with the multiplication of Shigella. Exponential growth of Shigella was interrupted at about the time Klebsiella populations attained a maximal size. In contrast, the presence of Klebsiella in an aerated mixture had little or no effect on Shigella multiplication because Klebsiella failed to attain a maximal population. Different environmental conditions resulted in different Klebsiella to Shigella ratios in mixed cultures. When conditions were favorable for Shigella multiplication, as shown by pure culture controls, the proportion of Shigella in the mixture was generally greater than when conditions were unfavorable.

  15. Draft Genome Sequence of Klebsiella pneumoniae Strain AS Isolated from Zhejiang Provincial Hospital of TCM, China

    PubMed Central

    Yang, Xue-Jing; Wang, Sai; Hou, Jia-Hui

    2016-01-01

    Klebsiella pneumoniae is a Gram-negative, nonmotile, encapsulated, lactose-fermenting, facultative anaerobic, rod-shaped bacterium. Here we present draft genome assemblies of Klebsiella pneumoniae AS, which was isolated in China. The genomic information will provide a better understanding of the physiology, adaptation, and evolution of K. pneumoniae. PMID:27660770

  16. Fatal sepsis caused by an unusual Klebsiella species that was misidentified by an automated identification system.

    PubMed

    Seki, Masafumi; Gotoh, Kazuyoshi; Nakamura, Shota; Akeda, Yukihiro; Yoshii, Tadashi; Miyaguchi, Shinichi; Inohara, Hidenori; Horii, Toshihiro; Oishi, Kazunori; Iida, Tetsuya; Tomono, Kazunori

    2013-05-01

    This is a description of fatal sepsis caused by infection with Klebsiella variicola, which is an isolate genetically related to Klebsiella pneumoniae. The patient's condition was incorrectly diagnosed as common sepsis caused by K. pneumoniae, which was identified using an automated identification system, but next-generation sequencing and the non-fermentation of adonitol finally identified the cause of sepsis as K. variicola.

  17. CTX-M-12 β-Lactamase in a Klebsiella pneumoniae Clinical Isolate in Colombia

    PubMed Central

    Villegas, Maria Virginia; Correa, Adriana; Perez, Federico; Zuluaga, Tania; Radice, Marcela; Gutkind, Gabriel; Casellas, José María; Ayala, Juan; Lolans, Karen; Quinn, John P.

    2004-01-01

    We describe the detection of the CTX-M-12 β-lactamase from a clinical isolate of Klebsiella pneumoniae in Colombia. Screening of nosocomial Klebsiella spp. and Escherichia coli isolates from a network of teaching hospitals revealed the presence of CTX-M enzymes in multiple cities. This is the first description of CTX-M in Colombia. PMID:14742223

  18. CTX-M-12 beta-lactamase in a Klebsiella pneumoniae clinical isolate in Colombia.

    PubMed

    Villegas, Maria Virginia; Correa, Adriana; Perez, Federico; Zuluaga, Tania; Radice, Marcela; Gutkind, Gabriel; Casellas, José María; Ayala, Juan; Lolans, Karen; Quinn, John P

    2004-02-01

    We describe the detection of the CTX-M-12 beta-lactamase from a clinical isolate of Klebsiella pneumoniae in Colombia. Screening of nosocomial Klebsiella spp. and Escherichia coli isolates from a network of teaching hospitals revealed the presence of CTX-M enzymes in multiple cities. This is the first description of CTX-M in Colombia.

  19. An Outbreak of Infections Caused by a Klebsiella pneumoniae ST11 Clone Coproducing Klebsiella pneumoniae Carbapenemase-2 and RmtB in a Chinese Teaching Hospital

    PubMed Central

    Li, Jun; Zou, Ming-Xiang; Wang, Hai-Chen; Dou, Qing-Ya; Hu, Yong-Mei; Yan, Qun; Liu, Wen-En

    2016-01-01

    Background: Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae bacteria, which cause serious disease outbreaks worldwide, was rarely detected in Xiangya Hospital, prior to an outbreak that occurred from August 4, 2014, to March 17, 2015. The aim of this study was to analyze the epidemiology and molecular characteristics of the K. pneumoniae strains isolated during the outbreak. Methods: Nonduplicate carbapenem-resistant K. pneumoniae isolates were screened for blaKPC-2 and multiple other resistance determinants using polymerase chain reaction. Subsequent studies included pulsed-field gel electrophoresis (PFGE), multilocus sequence typing, analysis of plasmids, and genetic organization of blaKPC-2 locus. Results: Seventeen blaKPC-2-positive K. pneumoniae were identified. A wide range of resistant determinants was detected. Most isolates (88.2%) coharbored blaKPC-2 and rmtB in addition to other resistance genes, including blaSHV-1, blaTEM-1, and aac(3)-IIa. The blaKPC-2 and rmtB genes were located on the conjugative IncFIB-type plasmid. Genetic organization of blaKPC-2 locusin most strains was consistent with that of the plasmid pKP048. Four types (A1, A2, A3, and B) were detected by PFGE, and Type A1, an ST11, was the predominant PFGE type. A novel K. pneumoniae sequence type (ST1883) related to ST11 was discovered. Conclusions: These isolates in our study appeared to be clonal and ST11 K. pneumoniae was the predominant clone attributed to the outbreak. Coharbing of blaKPC-2 and rmtB, which were located on a transferable plasmid, in clinical K. pneumoniae isolates may lead to the emergence of a new pattern of drug resistance. PMID:27569227

  20. Delay in Human Neutrophil Constitutive Apoptosis after Infection with Klebsiella pneumoniae Serotype K1

    PubMed Central

    Lee, Chen-Hsiang; Chuah, Seng-Kee; Tai, Wei-Chen; Chang, Chia-Chi; Chen, Fang-Ju

    2017-01-01

    Klebsiella pneumoniae serotype K1 is a major cause of invasive syndrome defined by liver abscess with metastatic infections at other body sites. This culprit is known to be resistant to neutrophil phagocytosis and bactericidal activity. We hypothesized that K. pneumoniae serotype K1 might regulate neutrophil apoptosis and enhance the survival of the infected neutrophils that might serve as a vector for dissemination of the bacteria. Two serotypes of K. pneumoniae, KP-M1 isolated from a patient with liver abscess and DT-X (an acapsular mutant strain of KP-M1), were used to infect human neutrophils. The infected neutrophils were examined for their cytotoxicity, annexin V staining, proteins, DNA fragmentation, cytokine production, and viability that are involved in apoptosis. We found that KP-M1 was not destroyed and the ingested bacteria survived within neutrophils. While the uninfected neutrophils became apoptotic within 10 h, the neutrophils infected with KP-M1 could survive up to 24 h post infection. Constitutive apoptosis of KP-M1-infected neutrophils was significantly delayed compared to that of DT-X-infected or uninfected neutrophils (p < 0.01). KP-M1 modulated the anti-apoptotic effects by down-regulating the ratio of Bax to Bcl-2 and Mcl-1, and then delayed caspase-3 activation in the neutrophils, which was accompanied by inducing the anti-apoptotic cytokine, IL-8. These data suggest that K. pneumoniae serotype K1 can prolong the lifespan of infected neutrophils by delaying constitutive apoptosis within the first several hours of infection.

  1. Ovine pulmonary surfactant induces killing of Pasteurella haemolytica, Escherichia coli, and Klebsiella pneumoniae by normal serum.

    PubMed Central

    Brogden, K A

    1992-01-01

    Pulmonary surfactant has been shown to play an increasingly important role in bacterial clearance at the alveolar surface in the lung. This study describes a bactericidal mechanism in which ovine pulmonary surfactant induces killing of Pasteurella haemolytica by normal serum. To demonstrate killing, six bacterial species were incubated first with pulmonary surfactant for 60 min at 37 degrees C and then with serum for an additional 60 min at 37 degrees C. P. haemolytica type A1 strains 82-25 and L101, a P. haemolytica type 2 strain, Escherichia coli, and Klebsiella pneumoniae were susceptible and Pasteurella multocida, Serratia marcescens, and Pseudomonas aeruginosa were not susceptible to killing by ovine pulmonary surfactant and normal serum. No bacteria incubated with bovine pulmonary surfactant were killed by normal serum. Although the species origin of pulmonary surfactant was selective, the species origin of serum was not. P. haemolytica incubated with ovine pulmonary surfactant was killed by fetal calf serum, gnotobiotic calf serum, pooled normal sheep serum, pooled normal rabbit serum, and pooled guinea pig serum. Ultrastructurally, killed P. haemolytica suspensions contained dead cells and cells distorted with vacuoles between the cytoplasmic membrane and the cytoplasm. The mechanism of killing did not correlate with concentrations of complement or lysozyme or titers of residual antibody in either the pulmonary surfactant or the serum, and killing was reduced by preincubation of surfactant with P. haemolytica lipopolysaccharide. Preliminary characterization of both surfactant and serum implicate a low-molecular-weight proteinaceous component in the surfactant and serum albumin in the serum. This mechanism may help clear certain gram-negative bacteria from the lungs of sheep as a part of the pulmonary innate defense system. Images PMID:1452351

  2. Introduction of bacteriophage Mu into bacteria of various genera and intergeneric gene transfer by RP4::Mu.

    PubMed

    Murooka, Y; Takizawa, N; Harada, T

    1981-01-01

    The host range of coliphage Mu was greatly expanded to various genera of gram-negative bacteria by using the hybrid plasmic RP4::Mu cts, which is temperature sensitive and which confers resistance to ampicillin, kanamycin, and tetracycline. These drug resistance genes were transferred from Escherichia coli to members of the general Klebsiella, Enterobacter, Citrobacter, Salmonella, Proteus, Erwinia, Serratia, Alcaligenes, Agrobacterium, Rhizobium, Pseudomonas, Acetobacter, and Bacillus. Mu phage was produced by thermal induction from the lysogens of all these drug-resistant bacteria except Bacillus. Mu phage and RP4 or the RP4::Mu plasmid were used to create intergeneric recombinant strains by transfer of some genes, including the arylsulfatase gene, between Klebsiella aerogenes and E. coli. Thus, genetic analysis and intergeneric gene transfer are possible in these RP4::Mu-sensitive bacteria.

  3. Klebsiella pneumoniae carrying bla NDM-1 gene in orthopedic practice.

    PubMed

    Gupta, Varsha; Bansal, Neha; Gupta, Ravi; Chander, Jagdish

    2014-09-01

    Emergence and spread of carbapenemases in Enterobacteriaceae is a cause of concern worldwide, the latest threat being New Delhi metallo-β-lactamase (NDM-1). This report is of an orthopedic case with fracture femur managed with internal fixation and bone grafting, who subsequently developed secondary infection with Klebsiella pneumoniae harboring bla NDM-1 gene. Minimum inhibitory concentration (MIC) of imipenem was ≥8 μg/ml by E-test, suggestive of carbapenemase production. Phenotypic and further genotypic detection confirmed the presence of bla NDM-1 gene. The isolate remained susceptible only to tigecycline, colistin, and polymyxin B.

  4. Klebsiella pneumoniae pharyngitis mimicking malignancy: a diagnostic dilemma.

    PubMed

    Yeh, C-F; Li, W-Y; Hsu, Y-B

    2014-12-01

    Acute pharyngitis is a common disease. However, acute pharyngitis caused by Klebsiella pneumoniae with a gross appearance mimicking hypopharyngeal malignancy has never previously been reported. We report the case of a 57-year-old man with a right hypopharyngeal tumor which was disclosed by fiberoptic laryngoscopy and computed tomography scan. However, both the frozen and final pathologies showed no evidence of malignant cells, and a bacterial culture revealed the growth of K. pneumoniae. The hypopharyngeal lesion completely regressed after 2 weeks of antibiotic treatment. Clinicians should perform biopsy along with tissue culture for tumor-like lesions because infectious agents can lead to lesions with malignancy-like appearance.

  5. Modulation of respiratory dendritic cells during Klebsiella pneumonia infection

    PubMed Central

    2013-01-01

    Background Klebsiella pneumoniae is a leading cause of severe hospital-acquired respiratory tract infections and death but little is known regarding the modulation of respiratory dendritic cell (DC) subsets. Plasmacytoid DC (pDC) are specialized type 1 interferon producing cells and considered to be classical mediators of antiviral immunity. Method By using multiparameter flow cytometry analysis we have analysed the modulation of respiratory DC subsets after intratracheal Klebsiella pneumonia infection. Results Data indicate that pDCs and MoDC were markedly elevated in the post acute pneumonia phase when compared to mock-infected controls. Analysis of draining mediastinal lymph nodes revealed a rapid increase of activated CD103+ DC, CD11b+ DC and MoDC within 48 h post infection. Lung pDC identification during bacterial pneumonia was confirmed by extended phenotyping for 120G8, mPDCA-1 and Siglec-H expression and by demonstration of high Interferon-alpha producing capacity after cell sorting. Cytokine expression analysis of ex vivo-sorted respiratory DC subpopulations from infected animals revealed elevated Interferon-alpha in pDC, elevated IFN-gamma, IL-4 and IL-13 in CD103+ DC and IL-19 and IL-12p35 in CD11b+ DC subsets in comparison to CD11c+ MHC-class IIlow cells indicating distinct functional roles. Antigen-specific naive CD4+ T cell stimulatory capacity of purified respiratory DC subsets was analysed in a model system with purified ovalbumin T cell receptor transgenic naive CD4+ responder T cells and respiratory DC subsets, pulsed with ovalbumin and matured with Klebsiella pneumoniae lysate. CD103+ DC and CD11b+ DC subsets represented the most potent naive CD4+ T helper cell activators. Conclusion These results provide novel insight into the activation of respiratory DC subsets during Klebsiella pneumonia infection. The detection of increased respiratory pDC numbers in bacterial pneumonia may indicate possible novel pDC functions with respect to lung repair

  6. First report of KPC-producing Klebsiella pneumoniae in Croatia.

    PubMed

    Bedenić, Branka; Mazzariol, Annarita; Plečko, Vanda; Bošnjak, Zrinka; Barl, Petra; Vraneš, Jasmina; Cornaglia, Giuseppe

    2012-08-01

    In February 2011, a 78-year-old male patient was admitted to Clinical Hospital Center Zagreb with subdural haematoma. Klebsiella pneumoniae with reduced susceptibility to carbapenems was isolated. PCR revealed the presence of bla(KPC), bla(TEM), and bla(SHV) genes. Sequencing of bla(KPC) gene identified K. pneumoniae carbapenemase (KPC)-2 beta-lactamase. The strain belonged to ST37 clone by multilocus sequence typing. Infection control efforts limited the spread of KPC-producing clone of K. pneumoniae in our hospital so far. To our knowledge, this is the first report of a KPC-producing K. pneumoniae in Croatia.

  7. The Link Between Klebsiella and Ankylosing Spondylitis in Worldwide Geographical Locations.

    PubMed

    Rashid, Taha; Ebringer, Alan; Wilson, Clyde

    2016-01-01

    Ankylosing spondylitis (AS) is a world-wide chronic inflammatory disease of the axial skeleton most likely caused by a microbial factor in genetically susceptible individuals. Over the last 40 years extensive data has been produced which shows that the majority of patients with AS possess the HLA-B27 genetic marker. Significantly elevated levels of Klebsiella antibodies have been demonstrated in 1556 AS patients in 16 different countries with various geographical locations. Other evidence for the link between Klebsiella and AS include increased fecal isolation rates of Klebsiella microbes in AS patients together with shared molecular and immunological cross-reactivity features existing between Klebsiella antigens and HLA-B27 and collagens I, III and IV. Anti-Klebsiella measures could possibly be included with the currently used medical treatment in the management of patients with AS.

  8. Susceptibility of Austrian Clinical Klebsiella and Enterobacter Isolates Linked to Patient-Related Data

    PubMed Central

    Badura, Alexandra; Pregartner, Gudrun; Holzer, Judith C.; Feierl, Gebhard; Grisold, Andrea J.

    2016-01-01

    The aim of the study was to analyze the antimicrobial susceptibility of Austrian clinical Klebsiella sp. and Enterobacter sp. isolates linked to patient-related data over a time period from 1998 to 2014. The main findings of this study were (i) a marked difference of antibiotic susceptibility rates between different infection sites for both Klebsiella sp. and Enterobacter sp., (ii) significantly greater percentages of resistant isolates among both Klebsiella sp. and Enterobacter sp. in male patients compared to female patients and (iii) significantly greater percentages of resistant isolates among both Klebsiella sp. and Enterobacter sp. from hospital-derived samples compared to samples from the community. In conclusion, our statistical data analysis clearly indicated a strong association of patient-related data and Klebsiella sp. and Enterobacter sp. susceptibility profiles. PMID:26903953

  9. Mannose-inhibitable adhesins and T3-T7 receptors of Klebsiella pneumoniae inhibit phagocytosis and intracellular killing by human polymorphonuclear leukocytes.

    PubMed Central

    Pruzzo, C; Debbia, E; Satta, G

    1982-01-01

    It has recently been shown that Klebsiella pneumoniae strains adhere to human epithelial cells and that adherence is mediated by mannose-inhibitable adhesins which are also receptors for coliphages T3 and T7. We have now found that Klebsiella strain K59, which adheres to human epithelial cells and carries the receptors for coliphages T3 and T7, adheres to human polymorphonuclear leukocytes (PMN) at 4 degrees C. Strains KRTT1 and KRTT2, which are spontaneous mutants unable to adsorb coliphages T3 and T7 and adhere to human epithelial cells, at this temperature did not adhere to PMN. Adherence of K59 cells to PMN at 4 degrees C was inhibited by D-mannose, by UV-inactivated T7 phages, and by pepsin-digested anti-K59 antibodies absorbed with KRTT1 cells. At 37 degrees C the number of PMN with KRTT bacteria associated was fourfold higher than at 4 degrees C. On the contrary, the number of PMN with K59 bacteria associated at this temperature was fourfold lower than at 4 degrees C. Phagocytosis and intracellular killing experiments performed at 37 degrees C showed that KRTT1 and KRTT2 were phagocytized and killed at a higher rate than K59. After blocking of the mannose-inhibitable adhesins and T3-T7 receptors (MIAT) by D-mannose, UV-inactivated bacteriophage T7, or specific antibodies, K59 cells became more sensitive to phagocytosis and intracellular killing at 37 degrees C. K59 cells lysogenic for prophage AP3 were approximately as sensitive to phagocytosis and intracellular killing by human PMN as strains KRTT1 and KRTT2. Unencapsulated Klebsiella strains isolated from clinical specimens were found to carry MIAT most often. Four such strains were found much more resistant to phagocytosis and intracellular killing than their spontaneous mutants resistant to bacteriophages T3 and T7. PMID:7047402

  10. High isolation rates of multidrug-resistant bacteria from water and carpets of mosques

    PubMed Central

    Mohamed Ali, Mostafa Mohamed; Alemary, Fuoad; Alrtail, Amna; Rzeg, Moftah M.; Albakush, Abdulla M.; Ghenghesh, Khalifa Sifaw

    2014-01-01

    Objective There is little information regarding the isolation of antimicrobial-resistant potentially pathogenic bacteria from water and carpets of mosques worldwide. The objective of the present investigation is to determine the bacteriological quality of water and carpets of mosques in Elkhomes city in Libya. Methods Potentially pathogenic bacteria were isolated from water samples (n=44) and dust samples from carpets (n=50) of 50 mosques in Elkhomes city, Libya, using standard bacteriological procedures. Susceptibility of isolated bacteria to antimicrobial agents was determined by the disc-diffusion method. Results Of the water samples examined, 12 (27.3%) were positive for Escherichia coli, 10 (22.7%) for Klebsiella spp., and 15 (34.1%) for other enteric bacteria. Of the dust samples of carpets examined, 6 (12%) were positive for E. coli, 33 (66%) for Klebsiella spp., and 30 (60%) for Staphylococcus spp. Multidrug resistance (MDR, resistance to three or more antimicrobial groups) was found among 48.7% (19/37) and 46.9% (30/64) of the examined enterobacteria from water and carpets, respectively, and among 66.7% (20/30) of Staphylococcus spp. from carpets. In addition, methicillin-resistant Staphylococcus aureus (MRSA) was isolated from a carpet of one mosque. Conclusion Presence of multidrug-resistant potentially pathogenic bacteria in examined water and carpets indicate that mosques as communal environments may play a role in the spread of multidrug-resistant bacteria in the community and pose a serious health risk to worshipers. PMID:25128691

  11. Nitrogen fixation by immobilized NIF derepressed Klebsiella pneumoniae cells

    SciTech Connect

    Venkatasubramanian, K.; Toda, Y.

    1980-01-01

    In vitro production of ammonia through biological means poses a number of challenges. The organisms should be able to accumulate considerable concentrations of ammonia in the medium. Secondly, nonphotosynthetic organisms must be supplied with high-energy substrates to carry out the fixation reaction. Thirdly, the organisms must be kept in a viable state to produce ammonia over long periods of time. In this article, preliminary results on the production of ammonia by a mutant strain of Klebsiella pneumoniae in continuous reactor systems are discussed. Continuous production of ammonia becomes feasible through the immobilization of the whole microbial cells and then through the use of the resulting catalyst system in a flow-through reactor. The rationale for immobilizing microbial cells and the advantages of such an approach over traditional fermentation processes are briefly described as they relate to the microbial production of ammonia. The microbial cells can be immobilized in such a way that their viability is still maintained in the immobilized state. This, in turn, obviates addition of cofactors, which is often an expensive step associated with immobilized multi-enzyme systems. Reconstituted bovine-hide collagen as the carrier matrix for fixing the cells was the carrier of choice for our work on immobilized Klebsiella cells. Polyacrylamide gels were examined as an alternate carrier matrix but results from this were found to be inferior to those collagen immobilized cell system.

  12. Modulation of Candida albicans attachment to human epithelial cells by bacteria and carbohydrates.

    PubMed Central

    Centeno, A; Davis, C P; Cohen, M S; Warren, M M

    1983-01-01

    The effects of carbohydrates (mannose and dextrose). Escherichia coli 07KL. and Klebsiella pneumoniae on Candida albicans attachment to epithelial cells was studied. Dextrose had no effect on yeast attachment to epithelial cells. Conversely, mannose significantly decreased both yeast and piliated bacterial attachment (E. coli 07KL, heavily piliated K. pneumoniae) whereas having no effect on nonpiliated K. pneumoniae attachment to epithelial cells. The number of yeasts attaching to epithelial cells was enhanced by preincubation of epithelial cells with piliated strains of bacteria, whereas preincubation with nonpiliated strains of bacteria had no effect on yeast attachment. Scanning electron microscopy showed that piliated bacteria and yeasts were juxtaposed on the epithelial cell surface. These data suggest that certain piliated strains of bacteria can enhance C. albicans attachment to epithelial cells and that type 1 pili of bacteria can be a factor in the enhanced attachment of C. albicans to epithelial cells. Images PMID:6132878

  13. Multidrug-resistant bacteria among patients with ventilatorassociated pneumonia in an emergency intensive care unit, Egypt.

    PubMed

    Azzab, Magda M; El-Sokkary, Rehab H; Tawfeek, Mohamed M; Gebriel, Manar G

    2017-02-01

    Ventilator-associated pneumonia (VAP) is the most common hospital-acquired infection among mechanically ventilated patients. Our objectives were to determine the incidence of VAP, isolate multidrug-resistant bacteria, identify the most prevalent resistant strains and identify their antibiotic susceptibility pattern. The VAP rate was calculated. The isolated microbes were identified and tested for antibiotic susceptibilities. The minimum inhibitory concentrations were determined of imipenem, meropenem and ertapenem for Klebsiella isolates. Klebsiella isolates resistant to carbapenems were tested for the presence of the blaKPC gene. The VAP incidence density rate was 48.8 incidences/1 000 ventilator days. The most common Gram-positive organism was Staphylococcus aureus, of which 86.6% of isolates were resistant to cefoxitin , but 100% were sensitive to teicoplanin, linezolid and tigecycline. The most common Gram-negative bacillus was Klebsiella, of which 94.6% of isolates were resistant to cefotaxime, 70.2% to imipenem, and 64.9% to ertapenem, but 100% were sensitive to colistin and 94.6% were sensitive to tigecycline. Of the carbapenem-resistant Klebsiella strains, 23.1% had the blaKPC gene. The high rates of VAP and the high rates of resistance among isolated organisms point to improper implementation of infection control programmes.

  14. Establishment of Experimental Murine Peritonitis Model with Hog Gastric Mucin for Carbapenem-Resistant Gram-Negative Bacteria

    PubMed Central

    Park, Chulmin; Chun, Hye-Sun; Byun, Ji-Hyun; Cho, Sung-Yeon

    2017-01-01

    Animal models are essential to studies of infectious diseases. The use of mice to test bacterial infection has been extensively reported. However, methods applied to clinical isolates, particularly for carbapenem-resistant bacteria, must be tailored according to the infection models and bacteria used. In this study, we infected 6-week-old female BALB/c mice intraperitoneally with different strains of resistant bacteria plus 3% hog gastric mucin. This method was found to be efficient and readily applicable for investigation of carbapenem-resisant Gram-negative pathogens (e.g., Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii) detected in Korea. PMID:28271653

  15. Mechanisms of polymyxin resistance: acquired and intrinsic resistance in bacteria

    PubMed Central

    Olaitan, Abiola O.; Morand, Serge; Rolain, Jean-Marc

    2014-01-01

    Polymyxins are polycationic antimicrobial peptides that are currently the last-resort antibiotics for the treatment of multidrug-resistant, Gram-negative bacterial infections. The reintroduction of polymyxins for antimicrobial therapy has been followed by an increase in reports of resistance among Gram-negative bacteria. Some bacteria, such as Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii, develop resistance to polymyxins in a process referred to as acquired resistance, whereas other bacteria, such as Proteus spp., Serratia spp., and Burkholderia spp., are naturally resistant to these drugs. Reports of polymyxin resistance in clinical isolates have recently increased, including acquired and intrinsically resistant pathogens. This increase is considered a serious issue, prompting concern due to the low number of currently available effective antibiotics. This review summarizes current knowledge concerning the different strategies bacteria employ to resist the activities of polymyxins. Gram-negative bacteria employ several strategies to protect themselves from polymyxin antibiotics (polymyxin B and colistin), including a variety of lipopolysaccharide (LPS) modifications, such as modifications of lipid A with phosphoethanolamine and 4-amino-4-deoxy-L-arabinose, in addition to the use of efflux pumps, the formation of capsules and overexpression of the outer membrane protein OprH, which are all effectively regulated at the molecular level. The increased understanding of these mechanisms is extremely vital and timely to facilitate studies of antimicrobial peptides and find new potential drugs targeting clinically relevant Gram-negative bacteria. PMID:25505462

  16. Absorption Coefficient Imaging by Near-Field Scanning Optical Microscopy in Bacteria

    NASA Astrophysics Data System (ADS)

    de Paula, Ana M.; Chaves, Claudilene R.; Silva, Haroldo B.; Weber, Gerald

    2003-06-01

    We present a method for obtaining a position-dependent absorption coefficient from near-field scanning optical transmission microscopy. We show that the optical transmission intensity can be combined with the topography, resulting into an absorption coefficient that simplifies the analysis of different materials within a sample. The method is tested with the dye rhodamine 6G, and we show some analysis in biological samples such as bacteria Klebsiella pneumoniae and Pseudomonas aeruginosa . The calculated absorption coefficient images show important details of the bacteria, in particular for P. aeruginosa , in which membrane vesicles are clearly seen.

  17. Effect of solar radiation and predacious microorganisms on survival of fecal and other bacteria.

    PubMed Central

    McCambridge, J; McMeekin, T A

    1981-01-01

    The effect of solar radiation and predacious microorganisms on the survival of bacteria of fecal and plant origin was studied. The decline in the numbers of Escherichia coli cells in estuarine water samples was found to be significantly greater in the presence of both naturally occurring microbial predators and solar radiation than when each of these factors was acting independently. The effect of solar radiation on microbial predators was negligible, whereas the susceptibility of bacteria to light-induced decay varied from one organism to another, as follows: Klebsiella pneumoniae greater than E. coli greater than Salmonella typhimurium, Streptococcus faecium, Enterobacter aerogenes, Erwinia herbicola. PMID:7020590

  18. Bacteria, biofilm and honey: a study of the effects of honey on 'planktonic' and biofilm-embedded chronic wound bacteria.

    PubMed

    Merckoll, Patricia; Jonassen, Tom Øystein; Vad, Marie Elisabeth; Jeansson, Stig L; Melby, Kjetil K

    2009-01-01

    Chronically infected wounds are a costly source of suffering. An important factor in the failure of a sore to heal is the presence of multiple species of bacteria, living cooperatively in highly organized biofilms. The biofilm protects the bacteria from antibiotic therapy and the patient's immune response. Honey has been used as a wound treatment for millennia. The components responsible for its antibacterial properties are now being elucidated. The study aimed to determine the effects of different concentrations of 'Medihoney' therapeutic honey and Norwegian Forest Honey 1) on the real-time growth of typical chronic wound bacteria; 2) on biofilm formation; and 3) on the same bacteria already embedded in biofilm. Reference strains of MRSE, MRSA, ESBL Klebsiella pneumoniae and Pseudomonas aeruginosa were incubated with dilution series of the honeys in microtitre plates for 20 h. Growth of the bacteria was assessed by measuring optical density every 10 min. Growth curves, biofilm formation and minimum bactericidal concentrations are presented. Both honeys were bactericidal against all the strains of bacteria. Biofilm was penetrated by biocidal substances in honey. Reintroduction of honey as a conventional wound treatment may help improve individual wound care, prevent invasive infections, eliminate colonization, interrupt outbreaks and thereby preserve current antibiotic stocks.

  19. Back To Bacteria.

    ERIC Educational Resources Information Center

    Flannery, Maura C.

    1997-01-01

    Explores new research about bacteria. Discusses bacterial genomes, archaea, unusual environments, evolution, pathogens, bacterial movement, biofilms, bacteria in the body, and a bacterial obsession. Contains 29 references. (JRH)

  20. Acute lung inflammation in Klebsiella pneumoniae B5055-induced pneumonia and sepsis in BALB/c mice: a comparative study.

    PubMed

    Kumar, Vijay; Chhibber, Sanjay

    2011-10-01

    Lungs play an important role in the body's defense against a variety of pathogens, but this network of immune system-mediated defense can be deregulated during acute pulmonary infections. The present study compares acute lung inflammation occurring during Klebsiella pneumoniae B5055-induced pneumonia and sepsis in BALB/c mice. Pneumonia was induced by intranasal instillation of bacteria (10(4) cfu), while sepsis was developed by placing the fibrin-thrombin clot containing known amount of bacteria (10(2) cfu) into the peritoneal cavity of animals. Mice with sepsis showed 100% mortality within five post-infection days, whereas all the animals with pneumonia survived. In animals suffering from K. pneumoniae B5055-induced pneumonia, all the inflammatory parameters (TNF-α, IL-1α, MPO, MDA, and NO) were found to be maximum till third post-infection day, after that, a decline was observed, whereas in septic animals, all the above-mentioned markers of inflammation kept on increasing. Histopathological study showed presence of alternatively activated alveolar macrophages (or foam cells) in lungs of mice with pneumonia after third post-infection day, which might have contributed to the induction of resolution of inflammation, but no such observation was made in lungs of septic mice. Hence, during pneumonia, controlled activation of macrophages may lead to resolution of inflammation.

  1. Photodynamic inactivation of Klebsiella pneumoniae biofilms and planktonic cells by 5-aminolevulinic acid and 5-aminolevulinic acid methyl ester.

    PubMed

    Liu, Chengcheng; Zhou, Yingli; Wang, Li; Han, Lei; Lei, Jin'e; Ishaq, Hafiz Muhammad; Nair, Sean P; Xu, Jiru

    2016-04-01

    The treatment of Klebsiella pneumoniae, particularly extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae, is currently a great challenge. Photodynamic antimicrobial chemotherapy is a promising approach for killing antibiotic-resistant bacteria. The aim of this study was to evaluate the capacity of 5-aminolevulinic acid (5-ALA) and its derivative 5-ALA methyl ester (MAL) in the presence of white light to cause photodynamic inactivation (PDI) of K. pneumoniae planktonic and biofilm cells. In the presence of white light, 5-ALA and MAL inactivated planktonic cells in a concentration-dependent manner. Biofilms were also sensitive to 5-ALA and MAL-mediated PDI. The mechanisms by which 5-ALA and MAL caused PDI of ESBL-producing K. pneumonia were also investigated. Exposure of K. pneumonia to light in the presence of either 5-ALA or MAL induced cleavage of genomic DNA and the rapid release of intracellular biopolymers. Intensely denatured cytoplasmic contents and aggregated ribosomes were also detected by transmission electron microscopy. Scanning electron microscopy showed that PDI of biofilms caused aggregated bacteria to detach and that the bacterial cell envelope was damaged. This study provides insights into 5-ALA and MAL-mediated PDI of ESBL-producing K. pneumoniae.

  2. N-glycosylated proteins are involved in efficient internalization of Klebsiella pneumoniae by cultured human epithelial cells.

    PubMed Central

    Fumagalli, O; Tall, B D; Schipper, C; Oelschlaeger, T A

    1997-01-01

    Klebsiella pneumoniae obtained from patients with urinary tract infections is able to invade cultured human epithelial cells. The internalization process is dependent upon both microfilaments and microtubules. To better understand the interaction of these invasive bacteria with the host cell receptor(s), bladder, lung, and ileocecal epithelial cells were infected with K. pneumoniae in the presence of various lectins possessing multiple glycan specificities. It was found that the N-acetylglucosamine (GlcNAc)-specific lectins concanavalin A, Datura stramonium agglutinin, and wheat germ agglutinin significantly inhibited the invasion of K. pneumoniae into these cells but did not interfere with the internalization of an invasive strain of Salmonella typhimurium. Conversely, internalization of K. pneumoniae but not S. typhimurium was also significantly inhibited when the bacteria were pretreated with GlcNAc or chitin hydrolysate, a GlcNAc polymer, prior to the gentamicin invasion assay. Other carbohydrates such as glucose, galactose, mannose, fucose, and N-acetylneuraminic acid had no inhibitory effects on K. pneumoniae uptake. Furthermore, internalization of K. pneumoniae but not S. typhimurium by HCT8 cells was also significantly inhibited when eukaryotic protein glycosylation was interrupted by tunicamycin or when host N-linked surface glycans were removed by pretreatment with N-glycosidase F. These studies suggest that a N-glycosylated protein receptor is involved in the internalization of K. pneumoniae by human epithelial cells in vitro. The results also indicate that internal GlcNAc residues might be a carbohydrate component of the receptor. PMID:9353018

  3. Ethanol production from glycerol-containing biodiesel waste by Klebsiella variicola shows maximum productivity under alkaline conditions.

    PubMed

    Suzuki, Toshihiro; Nishikawa, Chiaki; Seta, Kohei; Shigeno, Toshiya; Nakajima-Kambe, Toshiaki

    2014-05-25

    Biodiesel fuel (BDF) waste contains large amounts of crude glycerol as a by-product, and has a high alkaline pH. With regard to microbial conversion of ethanol from BDF-derived glycerol, bacteria that can produce ethanol at alkaline pH have not been reported to date. Isolation of bacteria that shows maximum productivity under alkaline conditions is essential to effective production of ethanol from BDF-derived glycerol. In this study, we isolated the Klebsiella variicola TB-83 strain, which demonstrated maximum ethanol productivity at alkaline pH. Strain TB-83 showed effective usage of crude glycerol with maximum ethanol production at pH 8.0-9.0, and the culture pH was finally neutralized by formate, a by-product. In addition, the ethanol productivity of strain TB-83 under various culture conditions was investigated. Ethanol production was more efficient with the addition of yeast extract. Strain TB-83 produced 9.8 g/L ethanol (0.86 mol/mol glycerol) from cooking oil-derived BDF waste. Ethanol production from cooking oil-derived BDF waste was higher than that of new frying oil-derived BDF and pure-glycerol. This is the first report to demonstrate that the K. variicola strain TB-83 has the ability to produce ethanol from glycerol at alkaline pH.

  4. Distinct but Spatially Overlapping Intestinal Niches for Vancomycin-Resistant Enterococcus faecium and Carbapenem-Resistant Klebsiella pneumoniae

    PubMed Central

    Caballero, Silvia; Carter, Rebecca; Ke, Xu; Sušac, Bože; Leiner, Ingrid M.; Kim, Grace J.; Miller, Liza; Ling, Lilan; Manova, Katia; Pamer, Eric G.

    2015-01-01

    Antibiotic resistance among enterococci and γ-proteobacteria is an increasing problem in healthcare settings. Dense colonization of the gut by antibiotic-resistant bacteria facilitates their spread between patients and also leads to bloodstream and other systemic infections. Antibiotic-mediated destruction of the intestinal microbiota and consequent loss of colonization resistance are critical factors leading to persistence and spread of antibiotic-resistant bacteria. The mechanisms underlying microbiota-mediated colonization resistance remain incompletely defined and are likely distinct for different antibiotic-resistant bacterial species. It is unclear whether enterococci or γ-proteobacteria, upon expanding to high density in the gut, confer colonization resistance against competing bacterial species. Herein, we demonstrate that dense intestinal colonization with vancomycin-resistant Enterococcus faecium (VRE) does not reduce in vivo growth of carbapenem-resistant Klebsiella pneumoniae. Reciprocally, K. pneumoniae does not impair intestinal colonization by VRE. In contrast, transplantation of a diverse fecal microbiota eliminates both VRE and K. pneumoniae from the gut. Fluorescence in situ hybridization demonstrates that VRE and K. pneumoniae localize to the same regions in the colon but differ with respect to stimulation and invasion of the colonic mucus layer. While VRE and K. pneumoniae occupy the same three-dimensional space within the gut lumen, their independent growth and persistence in the gut suggests that they reside in distinct niches that satisfy their specific in vivo metabolic needs. PMID:26334306

  5. Distinct but Spatially Overlapping Intestinal Niches for Vancomycin-Resistant Enterococcus faecium and Carbapenem-Resistant Klebsiella pneumoniae.

    PubMed

    Caballero, Silvia; Carter, Rebecca; Ke, Xu; Sušac, Bože; Leiner, Ingrid M; Kim, Grace J; Miller, Liza; Ling, Lilan; Manova, Katia; Pamer, Eric G

    2015-09-01

    Antibiotic resistance among enterococci and γ-proteobacteria is an increasing problem in healthcare settings. Dense colonization of the gut by antibiotic-resistant bacteria facilitates their spread between patients and also leads to bloodstream and other systemic infections. Antibiotic-mediated destruction of the intestinal microbiota and consequent loss of colonization resistance are critical factors leading to persistence and spread of antibiotic-resistant bacteria. The mechanisms underlying microbiota-mediated colonization resistance remain incompletely defined and are likely distinct for different antibiotic-resistant bacterial species. It is unclear whether enterococci or γ-proteobacteria, upon expanding to high density in the gut, confer colonization resistance against competing bacterial species. Herein, we demonstrate that dense intestinal colonization with vancomycin-resistant Enterococcus faecium (VRE) does not reduce in vivo growth of carbapenem-resistant Klebsiella pneumoniae. Reciprocally, K. pneumoniae does not impair intestinal colonization by VRE. In contrast, transplantation of a diverse fecal microbiota eliminates both VRE and K. pneumoniae from the gut. Fluorescence in situ hybridization demonstrates that VRE and K. pneumoniae localize to the same regions in the colon but differ with respect to stimulation and invasion of the colonic mucus layer. While VRE and K. pneumoniae occupy the same three-dimensional space within the gut lumen, their independent growth and persistence in the gut suggests that they reside in distinct niches that satisfy their specific in vivo metabolic needs.

  6. Multidrug-Resistant Bacteria Isolated from Surface Water in Bassaseachic Falls National Park, Mexico

    PubMed Central

    Delgado-Gardea, Ma. Carmen E.; Tamez-Guerra, Patricia; Gomez-Flores, Ricardo; Zavala-Díaz de la Serna, Francisco Javier; Eroza-de la Vega, Gilberto; Nevárez-Moorillón, Guadalupe Virginia; Pérez-Recoder, María Concepción; Sánchez-Ramírez, Blanca; González-Horta, María del Carmen; Infante-Ramírez, Rocío

    2016-01-01

    Bacterial pathogens are a leading cause of waterborne disease, and may result in gastrointestinal outbreaks worldwide. Inhabitants of the Bassaseachic Falls National Park in Chihuahua, Mexico show seasonal gastroenteritis problems. This aim of this study was to detect enteropathogenic microorganisms responsible for diarrheal outbreaks in this area. In 2013, 49 surface water samples from 13 selected sampling sites along the Basaseachi waterfall and its main rivers, were collected during the spring, summer, autumn, and winter seasons. Fecal and total coliform counts were determined using standard methods; the AutoScan-4 system was used for identification of isolates and the antibiotic resistance profile by challenging each organism using 21 antibiotics. Significant differences among seasons were detected, where autumn samples resulted in the highest total (p < 0.05) and fecal (p < 0.001) coliform counts, whereas the lowest total coliform counts were recorded in spring. Significant differences between sampling sites were observed, where samples from sites 6, 8, and 11 had the highest total coliform counts (p < 0.009), whereas samples from site 9 exhibited the lowest one. From the microbiological analysis, 33 bacterial isolates from 13 different sites and four sampling seasons were selected; 53% of isolates were resistant to at least one antibiotic, and 15% exhibited a multidrug resistance (MDB) phenotype. MDB were identified as Klebsiella oxytoca (two out of four identified isolates), Escherichia coli (2/7), and Enterobacter cloacae (1/3). In addition, some water-borne microorganisms exhibited resistance to cefazoline, cefuroxime, ampicillin, and ampicillin-sulbactam. The presence of these microorganisms near rural settlements suggests that wastewater is the contamination source, providing one possible transmission mechanism for diarrheal outbreaks. PMID:27322297

  7. Multidrug-Resistant Bacteria Isolated from Surface Water in Bassaseachic Falls National Park, Mexico.

    PubMed

    Delgado-Gardea, Ma Carmen E; Tamez-Guerra, Patricia; Gomez-Flores, Ricardo; Zavala-Díaz de la Serna, Francisco Javier; Eroza-de la Vega, Gilberto; Nevárez-Moorillón, Guadalupe Virginia; Pérez-Recoder, María Concepción; Sánchez-Ramírez, Blanca; González-Horta, María Del Carmen; Infante-Ramírez, Rocío

    2016-06-16

    Bacterial pathogens are a leading cause of waterborne disease, and may result in gastrointestinal outbreaks worldwide. Inhabitants of the Bassaseachic Falls National Park in Chihuahua, Mexico show seasonal gastroenteritis problems. This aim of this study was to detect enteropathogenic microorganisms responsible for diarrheal outbreaks in this area. In 2013, 49 surface water samples from 13 selected sampling sites along the Basaseachi waterfall and its main rivers, were collected during the spring, summer, autumn, and winter seasons. Fecal and total coliform counts were determined using standard methods; the AutoScan-4 system was used for identification of isolates and the antibiotic resistance profile by challenging each organism using 21 antibiotics. Significant differences among seasons were detected, where autumn samples resulted in the highest total (p < 0.05) and fecal (p < 0.001) coliform counts, whereas the lowest total coliform counts were recorded in spring. Significant differences between sampling sites were observed, where samples from sites 6, 8, and 11 had the highest total coliform counts (p < 0.009), whereas samples from site 9 exhibited the lowest one. From the microbiological analysis, 33 bacterial isolates from 13 different sites and four sampling seasons were selected; 53% of isolates were resistant to at least one antibiotic, and 15% exhibited a multidrug resistance (MDB) phenotype. MDB were identified as Klebsiella oxytoca (two out of four identified isolates), Escherichia coli (2/7), and Enterobacter cloacae (1/3). In addition, some water-borne microorganisms exhibited resistance to cefazoline, cefuroxime, ampicillin, and ampicillin-sulbactam. The presence of these microorganisms near rural settlements suggests that wastewater is the contamination source, providing one possible transmission mechanism for diarrheal outbreaks.

  8. Cockroaches as carriers of bacteria in multi-family dwellings.

    PubMed Central

    Cloarec, A.; Rivault, C.; Fontaine, F.; Le Guyader, A.

    1992-01-01

    The potential risk of bacterial dissemination due to the presence of cockroaches (Blattella germanica, Blattellidae) in low-income flats was investigated. Cockroaches can carry a great variety of bacterial species; we identified 30 different species from 52 different flats. Klebsiella oxycytoca, K. pneumoniae and Enterobacter cloacae were the most frequently found. Pathogenic and potentially pathogenic bacteria represented 54% of all the bacterial identifications. Bacteria were carried either on the cuticle or in the gut. Contamination through external contact is sufficient to insure bacterial diffusion. There was a very low level of overlap estimated by Pianka's index (a) between the bacterial flora of neighbouring blocks of flats, and (b) between bacterial flora of different flats in the same block. PMID:1468532

  9. Correlation between antimicrobial resistance and virulence in Klebsiella pneumoniae.

    PubMed

    Hennequin, C; Robin, F

    2016-03-01

    Klebsiella pneumoniae is responsible for a wide range of infections, including urinary tract infections, pneumonia, bacteremia, and liver abscesses. In addition to susceptible clinical isolates involved in nosocomial infections, multidrug-resistant (MDR) and hypervirulent (hvKP) strains have evolved separately in distinct clonal groups. The rapid geographic spread of these isolates is of particular concern. However, we still know little about the virulence of K. pneumoniae except for hvKP, whose secrets are beginning to be revealed. The treatment of K. pneumoniae infections is threatened by the emergence of antimicrobial resistance. The dissemination of resistance is associated with genetic mobile elements, such as plasmids that may also carry virulence determinants. A proficient pathogen should be virulent, resistant to antibiotics, and epidemic. However, the interplay between resistance and virulence is poorly understood. Here, we review current knowledge on the topic.

  10. Metabolism of benzonitrile and butyronitrile by Klebsiella pneumoniae

    SciTech Connect

    Nawaz, M.S.; Heinze, T.M.; Cerniglia, C.E. )

    1992-01-01

    A strain of Klebsiella pneumoniae that used aliphatic nitriles as the sole source of nitrogen was adapted to benzonitrile as the sole source of carbon and nitrogen. Gas chromatographic and mass spectral analyses of culture filtrates indicated that K. pneumoniae metabolized 8.4 mM benzonitrile to 4.0 mM benzoic acid and 2.7 mM ammonia. In addition, butyronitrile was metabolized to butyramide and ammonia. The isolate also degraded mixtures of benzonitrile and aliphatic nitriles. Cell extracts contained nitrile hydratase and amidase activities. The enzyme activities were higher with butyronitrile and butyramide than with benzonitrile and benzamide, and amidase activities were twofold higher than nitrile hydratase activities. K. pneumoniae appears promising for the bioremediation of sites contaminated with aliphatic and aromatic nitriles.

  11. Antibiotic Resistance Related to Biofilm Formation in Klebsiella pneumoniae

    PubMed Central

    Vuotto, Claudia; Longo, Francesca; Balice, Maria Pia; Donelli, Gianfranco; Varaldo, Pietro E.

    2014-01-01

    The Gram-negative opportunistic pathogen, Klebsiella pneumoniae, is responsible for causing a spectrum of community-acquired and nosocomial infections and typically infects patients with indwelling medical devices, especially urinary catheters, on which this microorganism is able to grow as a biofilm. The increasingly frequent acquisition of antibiotic resistance by K. pneumoniae strains has given rise to a global spread of this multidrug-resistant pathogen, mostly at the hospital level. This scenario is exacerbated when it is noted that intrinsic resistance to antimicrobial agents dramatically increases when K. pneumoniae strains grow as a biofilm. This review will summarize the findings about the antibiotic resistance related to biofilm formation in K. pneumoniae. PMID:25438022

  12. Phagocytic and chemiluminescent responses of mouse peritoneal macrophages to living and killed Salmonella typhimurium and other bacteria

    SciTech Connect

    Tomita, T.; Blumenstock, E.; Kanegasaki, S.

    1981-06-01

    In the presence of luminol, resident as well as thioglycolate-induced and immunized macrophages emitted chemiluminescence more efficiently when the cells were exposed to living Salmonella typhimurium than when they were exposed to the same bacterium killed by ultraviolet light or heat. This phenomenon was observed whether or not the bacterium was opsonized. The different response to living and killed bacteria was also found with Escherichia coli, Pseudomonas aeruginosa, Proteus morganii, and Enterobacter aerogenes, but not with Shigella sonnei, Klebsiella pneumoniae, and Propionibacterium acnes. The results suggest that macrophages respond better to living, motile bacteria than to nonmotile or killed bacteria. The experimental results obtained with motility mutants of S. typhimurium, E. coli, and P. aeruginosa confirm that macrophages exposed to the motile bacteria emit chemiluminescence more efficiently and ingest the motile bacteria at a much faster rate than the nonmotile bacteria.

  13. Identification of Klebsiella capsule synthesis loci from whole genome data

    PubMed Central

    Wick, Ryan R.; Gorrie, Claire; Jenney, Adam; Follador, Rainer; Thomson, Nicholas R.

    2016-01-01

    Klebsiella pneumoniae is a growing cause of healthcare-associated infections for which multi-drug resistance is a concern. Its polysaccharide capsule is a major virulence determinant and epidemiological marker. However, little is known about capsule epidemiology since serological typing is not widely accessible and many isolates are serologically non-typeable. Molecular typing techniques provide useful insights, but existing methods fail to take full advantage of the information in whole genome sequences. We investigated the diversity of the capsule synthesis loci (K-loci) among 2503 K. pneumoniae genomes. We incorporated analyses of full-length K-locus nucleotide sequences and also clustered protein-encoding sequences to identify, annotate and compare K-locus structures. We propose a standardized nomenclature for K-loci and present a curated reference database. A total of 134 distinct K-loci were identified, including 31 novel types. Comparative analyses indicated 508 unique protein-encoding gene clusters that appear to reassort via homologous recombination. Extensive intra- and inter-locus nucleotide diversity was detected among the wzi and wzc genes, indicating that current molecular typing schemes based on these genes are inadequate. As a solution, we introduce Kaptive, a novel software tool that automates the process of identifying K-loci based on full locus information extracted from whole genome sequences (https://github.com/katholt/Kaptive). This work highlights the extensive diversity of Klebsiella K-loci and the proteins that they encode. The nomenclature, reference database and novel typing method presented here will become essential resources for genomic surveillance and epidemiological investigations of this pathogen. PMID:28348840

  14. Evaluation of Biofilm Formation Among Klebsiella pneumoniae Isolates and Molecular Characterization by ERIC-PCR

    PubMed Central

    Seifi, Kimia; Kazemian, Hossein; Heidari, Hamid; Rezagholizadeh, Fereshteh; Saee, Yasaman; Shirvani, Fariba; Houri, Hamidreza

    2016-01-01

    Background: Klebsiella pneumoniae is among the most frequently recovered etiologic agents from nosocomial infections. This opportunistic pathogen can generate a thick layer of biofilm as one of its important virulence factors, enabling the bacteria to attach to living or abiotic surfaces, which contributes to drug resistance. Objectives: The resistance of biofilm-mediated infections to effective chemotherapy has adverse effects on patient outcomes and survival. Therefore, the aim of the present study was to evaluate the biofilm-formation capacity of clinical K. pneumoniae isolates and to perform a molecular characterization using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) to determine the dominant biofilm-producing genotype. Patients and Methods: In the present study, 94 K. pneumoniae isolates were obtained from two hospitals in Tehran, Iran. Biofilm formation was assayed by a modified procedure, then ERIC-PCR was carried out. Results: The distributions of the clinical specimens used in this study were 61.7% from urine, 18.1% from wounds, 11.7% from sputum, and 8.5% from blood. Among these isolates, 33% formed fully established biofilms, 52.1% were categorized as moderately biofilm-producing, 8.5% formed weak biofilms, and 6.4% were non-biofilm-producers. Genotyping of K. pneumoniae revealed 31 different ERIC types. Biofilm-formation ability in a special ERIC type was not observed. Conclusions: Our results indicated that an enormous proportion of K. pneumoniae isolated from sputum and surgical-wound swabs produced fully established biofilms. It is reasonable to assume the existence of a relationship between the site of infection and the formation of biofilm. A high level of genetic diversity among the K. pneumoniae strains was observed. PMID:27099694

  15. Interhospital spread of NDM-7-producing Klebsiella pneumoniae belonging to ST437 in Spain.

    PubMed

    Seara, Nieves; Oteo, Jesús; Carrillo, Raquel; Pérez-Blanco, Verónica; Mingorance, Jesús; Gómez-Gil, Rosa; Herruzo, Rafael; Pérez-Vázquez, María; Astray, Jenaro; García-Rodríguez, Julio; Ruiz-Velasco, Luis Moisés; Campos, José; de Burgos, Carmen; Ruiz-Carrascoso, Guillermo

    2015-08-01

    This study describes an interhospital spread of carbapenem-resistant Klebsiella pneumoniae (CRKP) producing NDM-7 carbapenemase that started in December 2013 in Madrid, Spain. NDM-7-producing CRKP were isolated from urine, rectal swabs or blood samples from seven patients admitted to three different hospitals (Hospital Universitario La Paz, Hospital de Cantoblanco and Hospital Central de la Cruz Roja). The isolates were resistant to all antimicrobials tested except colistin and fosfomycin. One blood isolate was susceptible to minocycline and tigecycline but was resistant to fosfomycin. All isolates were closely related by pulsed-field gel electrophoresis (PFGE) and DiversiLab(®) analysis and belonged to multilocus sequence typing (MLST) sequence type 437. In addition, blaNDM-7, blaTEM-1, blaCTX-M-15 and aac(3)-IIa were identified. Family contacts of the index case were negative for NDM-producing bacteria. The outbreak occurred in two separate waves and the cases associated with Hospital de Cantoblanco had been admitted to the same room. Environmental samples from the trap of a sink and a shower in this room were positive for NDM-7-producing CRKP. To our knowledge, this is the first reported worldwide outbreak of NDM-7-producing CRKP. No relationship with the Indian continent, the Balkans or the Middle East could be established. Frequent transfer of aged or chronically ill patients between the facilities involved may have favoured the spread of NDM-7-producing CRKP. The spread of the second wave in Hospital de Cantoblanco probably occurred as a result of transmission from an environmental reservoir.

  16. Identification of Outer Membrane and Exoproteins of Carbapenem-Resistant Multilocus Sequence Type 258 Klebsiella pneumoniae

    PubMed Central

    Brinkworth, Amanda J.; Hammer, Carl H.; Olano, L. Renee; Kobayashi, Scott D.; Chen, Liang; Kreiswirth, Barry N.; DeLeo, Frank R.

    2015-01-01

    Carbapenem-resistant Klebsiella pneumoniae strains have emerged as a cause of life-threatening infections in susceptible individuals (e.g., transplant recipients and critically ill patients). Strains classified as multilocus sequence type (ST) 258 are among the most prominent causes of carbapenem-resistant K. pneumoniae infections worldwide, but the basis for the success of this lineage remains incompletely determined. To gain a more comprehensive view of the molecules potentially involved in the success of ST258, we used a proteomics approach to identify surface-associated and culture supernatant proteins produced by ST258. Protein samples were prepared from varied culture conditions in vitro, and were analyzed by a combination of two-dimensional electrophoresis and liquid chromatography followed by tandem mass spectrometry (LC-MS/MS). We identified a total of 193 proteins in outer membrane preparations from bacteria cultured in Luria-Bertani broth (LB) or RPMI 1640 tissue culture media (RPMI). Compared with LB, several iron-acquisition proteins, including IutA, HmuR, HmuS, CirA, FepA, FitA, FoxA, FhuD, and YfeX, were more highly expressed in RPMI. Of the 177 proteins identified in spent media, only the fimbrial subunit, MrkA, was predicted to be extracellular, a finding that suggests few proteins (or a limited quantity) are freely secreted by ST258. Notably, we discovered 203 proteins not reported in previous K. pneumoniae proteome studies. In silico modeling of proteins with unknown function revealed several proteins with beta-barrel transmembrane structures typical of porins, as well as possible host-interacting proteins. Taken together, these findings contribute several new targets for the mechanistic study of drug-resistance and pathogenesis by ST258 K. pneumoniae isolates. PMID:25893665

  17. Plasmid Dynamics in KPC-Positive Klebsiella pneumoniae during Long-Term Patient Colonization

    PubMed Central

    Park, Morgan; Deming, Clayton; Thomas, Pamela J.; Young, Alice C.; Coleman, Holly; Sison, Christina; Weingarten, Rebecca A.; Lau, Anna F.; Dekker, John P.; Palmore, Tara N.; Frank, Karen M.

    2016-01-01

    ABSTRACT Carbapenem-resistant Klebsiella pneumoniae strains are formidable hospital pathogens that pose a serious threat to patients around the globe due to a rising incidence in health care facilities, high mortality rates associated with infection, and potential to spread antibiotic resistance to other bacterial species, such as Escherichia coli. Over 6 months in 2011, 17 patients at the National Institutes of Health (NIH) Clinical Center became colonized with a highly virulent, transmissible carbapenem-resistant strain of K. pneumoniae. Our real-time genomic sequencing tracked patient-to-patient routes of transmission and informed epidemiologists’ actions to monitor and control this outbreak. Two of these patients remained colonized with carbapenemase-producing organisms for at least 2 to 4 years, providing the opportunity to undertake a focused genomic study of long-term colonization with antibiotic-resistant bacteria. Whole-genome sequencing studies shed light on the underlying complex microbial colonization, including mixed or evolving bacterial populations and gain or loss of plasmids. Isolates from NIH patient 15 showed complex plasmid rearrangements, leaving the chromosome and the blaKPC-carrying plasmid intact but rearranging the two other plasmids of this outbreak strain. NIH patient 16 has shown continuous colonization with blaKPC-positive organisms across multiple time points spanning 2011 to 2015. Genomic studies defined a complex pattern of succession and plasmid transmission across two different K. pneumoniae sequence types and an E. coli isolate. These findings demonstrate the utility of genomic methods for understanding strain succession, genome plasticity, and long-term carriage of antibiotic-resistant organisms. PMID:27353756

  18. Polymyxin B in combination with meropenem against carbapenemase-producing Klebsiella pneumoniae: pharmacodynamics and morphological changes.

    PubMed

    Sharma, Rajnikant; Patel, Saloni; Abboud, Cely; Diep, John; Ly, Neang S; Pogue, Jason M; Kaye, Keith S; Li, Jian; Rao, Gauri G

    2017-02-01

    Combination therapy provides a useful therapeutic approach to overcome resistance until new antibiotics become available. In this study, the pharmacodynamics, including the morphological effects, of polymyxin B (PMB) and meropenem alone and in combination against KPC-producing Klebsiella pneumoniae clinical isolates was examined. Ten clinical isolates were obtained from patients undergoing treatment for mediastinitis. KPCs were identified and MICs were measured using microbroth dilution. Time-kill studies were conducted over 24 h with PMB (0.5-16 mg/L) and meropenem (20-120 mg/L) alone or in combination against an initial inoculum of ca. 10(6) CFU/mL. Scanning electron microscopy (SEM) was employed to analyse changes in bacterial morphology after treatment, and the log change method was used to quantify the pharmacodynamic effect. All isolates harboured the blaKPC-2 gene and were resistant to meropenem (MICs ≥8 mg/L). Clinically relevant PMB concentrations (0.5, 1.0 and 2.0 mg/L) in combination with meropenem were synergistic against all isolates except BRKP28 (polymyxin- and meropenem-resistant, both MICs >128 mg/L). All PMB and meropenem concentrations in combination were bactericidal against polymyxin-susceptible isolates with meropenem MICs ≤16 mg/L. SEM revealed extensive morphological changes following treatment with PMB in combination with meropenem compared with the changes observed with each individual agent. Additionally, morphological changes decreased with increasing resistance profiles of the isolate, i.e. increasing meropenem MIC. These antimicrobial effects may not only be a summation of the effects due to each antibiotic but also a result of differential action that likely inhibits protective mechanisms in bacteria.

  19. Inhibition of Klebsiella β-Lactamases (SHV-1 and KPC-2) by Avibactam: A Structural Study

    PubMed Central

    Papp-Wallace, Krisztina M.; Bonomo, Robert A.; van den Akker, Focco

    2015-01-01

    β-Lactamase inhibition is an important clinical strategy in overcoming β-lactamase-mediated resistance to β-lactam antibiotics in Gram negative bacteria. A new β-lactamase inhibitor, avibactam, is entering the clinical arena and promising to be a major step forward in our antibiotic armamentarium. Avibactam has remarkable broad-spectrum activity in being able to inhibit classes A, C, and some class D β-lactamases. We present here structural investigations into class A β-lactamase inhibition by avibactam as we report the crystal structures of SHV-1, the chromosomal penicillinase of Klebsiella pneumoniae, and KPC-2, an acquired carbapenemase found in the same pathogen, complexed with avibactam. The 1.80 Å KPC-2 and 1.42 Å resolution SHV-1 β-lactamase avibactam complex structures reveal avibactam covalently bonded to the catalytic S70 residue. Analysis of the interactions and chair-shaped conformation of avibactam bound to the active sites of KPC-2 and SHV-1 provides structural insights into recently laboratory-generated amino acid substitutions that result in resistance to avibactam in KPC-2 and SHV-1. Furthermore, we observed several important differences in the interactions with amino acid residues, in particular that avibactam forms hydrogen bonds to S130 in KPC-2 but not in SHV-1, that can possibly explain some of the different kinetic constants of inhibition. Our observations provide a possible reason for the ability of KPC-2 β-lactamase to slowly desulfate avibactam with a potential role for the stereochemistry around the N1 atom of avibactam and/or the presence of an active site water molecule that could aid in avibactam desulfation, an unexpected consequence of novel inhibition chemistry. PMID:26340563

  20. Characterization of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae from Riyadh, Saudi Arabia.

    PubMed

    Al-Qahtani, Ahmed A; Al-Agamy, Mohamed H; Ali, Mohamed S; Al-Ahdal, Mohammad N; Aljohi, Mohammad A; Shibl, Atef M

    2014-06-01

    The objectives of this study were to determine the prevalences, genotypes, and clonal relationships of extended-spectrum beta-lactamase (ESBL)-producing strains in 98 Klebsiella pneumoniae isolates from Riyadh. The prevalence of ESBLs in these strains was 37·75%. All isolates that were confirmed to have ESBLs were completely resistant to amoxicillin/clavulanate, aztreonam, cefotaxime, ceftazidime, cefoxitin, and gentamicin and were susceptible to tigecycline, colistin, and imipenem. In total, 16·6, 77, and 91·6% of isolates were resistant to amikacin, ciprofloxacin, and piperacillin/tazobactam, respectively. The prevalences of isolates producing the beta-lactamases SHV, CTX-M, and TEM were 91·9, 86·5, and 54·05%, respectively. The most frequent ESBL gene detected was blaCTX-M-15, which was observed in 75% of isolates. Other frequent ESBL genes were blaSHV-12 (29·73% of isolates) and blaSHV-5 (5·4% of isolates); additionally, blaCTX-M-3, blaCTX-M-27, blaCTX-M-57, and blaCTX-M-82 were each detected in one isolate. Pulsed-field gel electrophoresis (PFGE) analysis revealed the presence of diverse and unrelated clones. The high prevalence of ESBL producers among the strains examined in our study was not due to the spread of a single clone of bacteria. Clone A was detected in six isolates, indicating intra-hospital spread. Our study documented a high prevalence of the CTX-M-15 product in K. pneumoniae and demonstrated that SHV-12 was also highly prevalent. This study represents the first report of CTX-M-3, CTX-M-27, CTX-M-57, and CTX-M-82 beta-lactamases in K. pneumoniae isolates from Saudi Arabia.

  1. Presence of Nitrogen Fixing Klebsiella pneumoniae in the gut of the Formosan Subterranean Termite (Coptotermes formosanus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A gram-negative facultative anaerobic enteric bacterium, Klebsiella pneumoniae was isolated from the hindgut of the Formosan subterranean termite (FST). It was characterized using, Fatty acid methyl ester (FAME) analysis, BIOLOG assay, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-...

  2. Complete Genome Sequence of Carbapenem-Resistant Klebsiella pneumoniae Strain 1756, Isolated from a Pus Specimen

    PubMed Central

    Kao, Cheng-Yen; Yan, Jing-Jou; Lin, Yu-Chun; Zheng, Po-Xing

    2017-01-01

    ABSTRACT Carbapenem-resistant Klebsiella pneumoniae strain 1756 was isolated from a pus specimen from a Taiwanese patient. Here, the complete genome sequence of strain 1756 is presented. PMID:28360152

  3. Draft Genome Sequence of Klebsiella pneumoniae subsp. pneumoniae ATCC 9621.

    PubMed

    Poehlein, Anja; Najdenski, Hristo; Simeonova, Diliana D

    2017-03-23

    We present here the 5.561-Mbp assembled draft genome sequence of Klebsiella pneumoniae subsp. pneumoniae ATCC 9621, a phosphite- and organophosphonate-assimilating Gammaproteobacterium. The genome harbors 5,179 predicted protein-coding genes.

  4. Ferric ammonium citrate decomposition--a taxonomic tool for gram-negative bacteria.

    PubMed

    Szentmihályi, A; Lányi, B

    1986-01-01

    The iron uptake test of Szabó and Vandra has been modified and used for the differentiation of Gram-negative bacteria. Nutrient agar containing 20 g per litre of ferric ammonium citrate was distributed into narrow tubes and solidified so as to form butts and slants. Considering the localization of the rusty-brown coloration produced after seeding and incubation, 2367 strains were classified into four groups. (1) Unchanged medium: Escherichia coli, Shigella spp., Yersinia spp., Hafnia alvei and Morganella morganii 100% each, Klebsiella spp., 50%, Enterobacter cloacae 37%, Proteus vulgaris 59%, Acinetobacter spp. 42%, Pseudomonas fluorescens 19%, some other bacteria 2-12%. (2) Rusty-brown slant, unchanged butt: Salmonella subgenera II, III and IV 98%, Citrobacter freundii 65%, E. cloacae 55%, P. vulgaris 41%, Proteus mirabilis 98%, Providencia rettgeri 100%, urease-negative Providencia 96%, Acinetobacter spp. 58%, Pseudomonas aeruginosa 100%, P. fluorescens 81%, UFP (unclassified fluorescent pseudomonads) 100%, other Pseudomonas spp. 55%. (3) Unchanged slant, brown butt: S. typhi 88%, Salmonella subgenus I 3%, Klebsiella spp. 31%, some other bacteria 2-3%. (4) Rusty-brown slant, brown butt: Salmonella subgenus I 75%, C. freundii 20%, Klebsiella spp. 12%, some other bacteria 1-5%. Colour reactions in ferric ammonium citrate agar are associated with the accumulation of ferric hydroxide: bacteria giving positive reactions on the slant took up as an average, 63 times more iron than those with negative test. The localization of colour reaction correlated partly with aerobic and anaerobic citrate utilization or decomposition in Simmons' minimal and in Kauffmann's peptone water medium.

  5. Genome Sequence of Klebsiella pneumoniae Bacteriophage PMBT1 Isolated from Raw Sewage

    PubMed Central

    Brinks, Erik; Fiedler, Gregor; Hüsing, Christina; Cho, Gyu-Sung; Hoeppner, Marc P.; Heller, Knut J.; Neve, Horst; Franz, Charles M. A. P.

    2017-01-01

    ABSTRACT A bacteriophage virulent for extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae strain 182 was isolated from sewage. The double-stranded DNA (dsDNA) genome showed high similarity to the genomes of other Klebsiella pneumoniae phages. It comprises 175,206 bp with a mol% G+C content of 41.9 and contains 276 putative open reading frames (ORFs) and one tRNA. PMID:28232430

  6. A multiple antibiotic and serum resistant oligotrophic strain, Klebsiella pneumoniae MB45 having novel dfrA30, is sensitive to ZnO QDs

    PubMed Central

    2011-01-01

    Background The aim of this study was to describe a novel trimethoprim resistance gene cassette, designated dfrA30, within a class 1 integron in a facultatively oligotrophic, multiple antibiotic and human serum resistant test strain, MB45, in a population of oligotrophic bacteria isolated from the river Mahananda; and to test the efficiency of surface bound acetate on zinc oxide quantum dots (ZnO QDs) as bactericidal agent on MB45. Methods Diluted Luria broth/Agar (10-3) media was used to cultivate the oligotrophic bacteria from water sample. Multiple antibiotic resistant bacteria were selected by employing replica plate method. A rapid assay was performed to determine the sensitivity/resistance of the test strain to human serum. Variable region of class 1 integron was cloned, sequenced and the expression of gene coding for antibiotic resistance was done in Escherichia coli JM 109. Identity of culture was determined by biochemical phenotyping and 16S rRNA gene sequence analyses. A phylogenetic tree was constructed based on representative trimethoprim resistance-mediating DfrA proteins retrieved from GenBank. Growth kinetic studies for the strain MB45 were performed in presence of varied concentrations of ZnO QDs. Results and conclusions The facultatively oligotrophic strain, MB45, resistant to human serum and ten antibiotics trimethoprim, cotrimoxazole, ampicillin, gentamycin, netilmicin, tobramycin, chloramphenicol, cefotaxime, kanamycin and streptomycin, has been identified as a new strain of Klebsiella pneumoniae. A novel dfr gene, designated as dfrA30, found integrated in class 1 integron was responsible for resistance to trimethoprim in Klebsiella pneumoniae strain MB45. The growth of wild strain MB45 was 100% arrested at 500 mg/L concentration of ZnO QDs. To our knowledge this is the first report on application of ZnO quantum dots to kill multiple antibiotics and serum resistant K. pneumoniae strain. PMID:21595893

  7. Coliform Bacteria and Nitrogen Fixation in Pulp and Paper Mill Effluent Treatment Systems

    PubMed Central

    Gauthier, Francis; Neufeld, Josh D.; Driscoll, Brian T.; Archibald, Frederick S.

    2000-01-01

    The majority of pulp and paper mills now biotreat their combined effluents using activated sludge. On the assumption that their wood-based effluents have negligible fixed N, and that activated-sludge microorganisms will not fix significant N, these mills routinely spend large amounts adding ammonia or urea to their aeration tanks (bioreactors) to permit normal biomass growth. N2 fixation in seven Eastern Canadian pulp and paper mill effluent treatment systems was analyzed using acetylene reduction assays, quantitative nitrogenase (nifH) gene probing, and bacterial isolations. In situ N2 fixation was undetectable in all seven bioreactors but was present in six associated primary clarifiers. One primary clarifier was studied in greater detail. Approximately 50% of all culturable cells in the clarifier contained nifH, of which >90% were Klebsiella strains. All primary-clarifier coliform bacteria growing on MacConkey agar were identified as klebsiellas, and all those probed contained nifH. In contrast, analysis of 48 random coliform isolates from other mill water system locations showed that only 24 (50%) possessed the nifH gene, and only 13 (27%) showed inducible N2-fixing activity. Thus, all the pulp and paper mill primary clarifiers tested appeared to be sites of active N2 fixation (0.87 to 4.90 mg of N liter−1 day−1) and a microbial community strongly biased toward this activity. This may also explain why coliform bacteria, especially klebsiellas, are indigenous in pulp and paper mill water systems. PMID:11097883

  8. Adherence of bacteria to heart valves in vitro.

    PubMed

    Gould, K; Ramirez-Ronda, C H; Holmes, R K; Sanford, J P

    1975-12-01

    The abilities of 14 strains of aerobic gram-positive cocci and gram-negative bacilli to adhere in vitro to human or canine aortic valve leaflets were compared. 2-mm sections of excised valve leaflets were obtained by punch biopsy and were incubated under standardized conditions in suspensions of bacteria. Valve sections were subsequently washed and homogenized, and quantitative techniques were used to determine the proportions of bacteria from the initial suspensions that had adhered to the valve sections. Comparable results were obtained when these adherence ratios were determined by two independent methods based either on measurements of bacterial viability or of radioactivity in 51Cr-labeled bacteria. For each bacterial strain, the adherence ratio was constant over a wide range of concentrations of bacteria in the incubation medium. Strains of enterococci, viridans streptococci, coagulase-positive and coagulase-negative staphylococci and Pseudomonas aeruginosa (adherence ratios 0.003-0.017) were found to adhere more readily to valve sections than strains of Escherichia coli and Klebsiella pneumoniae (adherence ratios 0.00002-0.00004). The organisms that most frequently cause bacterial endocarditis were found to adhere best to heart valves in vitro, suggesting that the ability to adhere to valvular endothelium may be an important or essential charcteristic of bacteria that cause endocarditis in man.

  9. Receptor for Advanced Glycation End Products (RAGE) Serves a Protective Role during Klebsiella pneumoniae - Induced Pneumonia.

    PubMed

    Achouiti, Ahmed; de Vos, Alex F; van 't Veer, Cornelis; Florquin, Sandrine; Tanck, Michael W; Nawroth, Peter P; Bierhaus, Angelika; van der Poll, Tom; van Zoelen, Marieke A D

    2016-01-01

    Klebsiella species is the second most commonly isolated gram-negative organism in sepsis and a frequent causative pathogen in pneumonia. The receptor for advanced glycation end products (RAGE) is expressed on different cell types and plays a key role in diverse inflammatory responses. We here aimed to investigate the role of RAGE in the host response to Klebsiella (K.) pneumoniae pneumonia and intransally inoculated rage gene deficient (RAGE-/-) and normal wild-type (Wt) mice with K. pneumoniae. Klebsiella pneumonia resulted in an increased pulmonary expression of RAGE. Furthermore, the high-affinity RAGE ligand high mobility group box-1 was upregulated during K. pneumoniae pneumonia. RAGE deficiency impaired host defense as reflected by a worsened survival, increased bacterial outgrowth and dissemination in RAGE-/- mice. RAGE-/- neutrophils showed a diminished phagocytosing capacity of live K. pneumoniae in vitro. Relative to Wt mice, RAGE-/- mice demonstrated similar lung inflammation, and slightly elevated-if any-cytokine and chemokine levels and unchanged hepatocellular injury. In addition, RAGE-/- mice displayed an unaltered response to intranasally instilled Klebsiella lipopolysaccharide (LPS) with respect to pulmonary cell recruitment and local release of cytokines and chemokines. These data suggest that (endogenous) RAGE protects against K. pneumoniae pneumonia. Also, they demonstrate that RAGE contributes to an effective antibacterial defense during K. pneumoniae pneumonia, at least partly via its participation in the phagocytic properties of professional granulocytes. Additionally, our results indicate that RAGE is not essential for the induction of a local and systemic inflammatory response to either intact Klebsiella or Klebsiella LPS.

  10. Bacteriocins active against multi-resistant gram negative bacteria implicated in nosocomial infections.

    PubMed

    Ghodhbane, Hanen; Elaidi, Sabrine; Sabatier, Jean-Marc; Achour, Sami; Benhmida, Jeannette; Regaya, Imed

    2015-01-01

    Multiresistant Gram-negative bacteria are the prime mover of nosocomial infections. Some are naturally resistant to antibiotics, their genetic makes them insensitive to certain families of antibiotics and they transmit these resistors to their offspring. Moreover, when bacteria are subjected to antibiotics, they eventually develop resistance against drugs to which they were previously sensitive. In recent years, many bacteriocins active against gram-negative bacteria have been identified proving their efficacy in treating infections. While further investigation remains necessary before the possibilities for bacteriocins in clinical practice can be described more fully, this review provides an overview of bacteriocins acting on the most common infectious gram negative bacteria (Klebsiella, Acinetobacter, Pseudomonas aeruginosa and E. coli).

  11. Report on a transborder spread of carbapenemase-producing bacteria by a patient injured during Euromaidan, Ukraine.

    PubMed

    Hrabák, J; Študentová, V; Adámková, V; Šemberová, L; Kabelíková, P; Hedlová, D; Čurdová, M; Zemlickova, H; Papagiannitsis, C C

    2015-11-01

    Spread of carbapenemase-producing bacteria has been described all over the world. This phenomenon may be accelerated by many factors, including wars and natural disasters. In this report, we described an NDM-1-producing Klebsiella pneumonia ST11 recovered from a patient injured during the Maidan revolution in Ukraine. To our knowledge, this is the first report of a carbapenemase-producing Enterobacteriaceae in Ukraine and one of several reports describing wound colonization/infection of humans injured during war.

  12. Structural and Functional Characterization of Aerobactin Synthetase IucA from a Hypervirulent Pathotype of Klebsiella pneumoniae

    SciTech Connect

    Bailey, Daniel C.; Drake, Eric J.; Grant, Thomas D.; Gulick, Andrew M.

    2016-06-28

    Iron is a vital mineral nutrient required by virtually all life forms to prosper; pathogenic bacteria are no exception. Despite the abundance of iron within the human host, highly regulated iron physiology can result in exceedingly low levels of iron bioavailable to prospective invading bacteria. To combat this scarcity of iron, many pathogenic bacteria have acquired specific and efficient iron acquisition systems, which allow them to thrive in iron-deficient host environments. One of the more prominent bacterial iron acquisition systems involves the synthesis, secretion, and reuptake of small-molecule iron chelators known as siderophores. Aerobactin, a citrate-hydroxamate siderophore originally isolated nearly 50 years ago, is produced by a number of pathogenic Gram-negative bacteria. Aerobactin has recently been demonstrated to play a pivotal role in mediating the enhanced virulence of a particularly invasive pathotype of Klebsiella pneumoniae (hvKP). Toward further understanding of this key virulence factor, we report the structural and functional characterization of aerobactin synthetase IucA from a strain of hvKP. The X-ray crystal structures of unliganded and ATP-bound forms of IucA were solved, forming the foundation of our structural analysis. Small angle X-ray scattering (SAXS) data suggest that, unlike its closest structurally characterized homologues, IucA adopts a tetrameric assembly in solution. Finally, we employed activity assays to investigate the substrate specificity and determine the apparent steady-state kinetic parameters of IucA.

  13. Fe(III) oxides accelerate microbial nitrate reduction and electricity generation by Klebsiella pneumoniae L17.

    PubMed

    Liu, Tongxu; Li, Xiaomin; Zhang, Wei; Hu, Min; Li, Fangbai

    2014-06-01

    Klebsiella pneumoniae L17 is a fermentative bacterium that can reduce iron oxide and generate electricity under anoxic conditions, as previously reported. This study reveals that K. pneumoniae L17 is also capable of dissimilatory nitrate reduction, producing NO2(-), NH4(+), NO and N2O under anoxic conditions. The presence of Fe(III) oxides (i.e., α-FeOOH, γ-FeOOH, α-Fe2O3 and γ-Fe2O3) significantly accelerates the reduction of nitrate and generation of electricity by K. pneumoniae L17, which is similar to a previous report regarding another fermentative bacterium, Bacillus. No significant nitrate reduction was observed upon treatment with Fe(2+) or α-FeOOH+Fe(2+), but a slight facilitation of nitrate reduction and electricity generation was observed upon treatment with L17+Fe(2+). This result suggests that aqueous Fe(II) or mineral-adsorbed Fe(II) cannot reduce nitrate abiotically but that L17 can catalyze the reduction of nitrate and generation of electricity in the presence of Fe(II) (which might exist as cell surface-bound Fe(II)). To rule out the potential effect of Fe(II) produced by L17 during microbial iron reduction, treatments with the addition of TiO2 or Al2O3 instead of Fe(III) oxides also exhibited accelerated microbial nitrate reduction and electricity generation, indicating that cell-mineral sorption did account for the acceleration effect. However, the acceleration caused by Fe(III) oxides is only partially attributed to the cell surface-bound Fe(II) and cell-mineral sorption but may be driven by the iron oxide conduction band-mediated electron transfer from L17 to nitrate or an electrode, as proposed previously. The current study extends the diversity of bacteria of which nitrate reduction and electricity generation can be facilitated by the presence of iron oxides and confirms the positive role of Fe(III) oxides on microbial nitrate reduction and electricity generation by particular fermentative bacteria in anoxic environments.

  14. Comparative analysis of diguanylate cyclase and phosphodiesterase genes in Klebsiella pneumoniae

    PubMed Central

    2012-01-01

    Background Klebsiella pneumoniae can be found in environmental habitats as well as in hospital settings where it is commonly associated with nosocomial infections. One of the factors that contribute to virulence is its capacity to form biofilms on diverse biotic and abiotic surfaces. The second messenger Bis-(3’-5’)-cyclic dimeric GMP (c-di-GMP) is a ubiquitous signal in bacteria that controls biofilm formation as well as several other cellular processes. The cellular levels of this messenger are controlled by c-di-GMP synthesis and degradation catalyzed by diguanylate cyclase (DGC) and phophodiesterase (PDE) enzymes, respectively. Many bacteria contain multiple copies of these proteins with diverse organizational structure that highlight the complex regulatory mechanisms of this signaling network. This work was undertaken to identify DGCs and PDEs and analyze the domain structure of these proteins in K. pneumoniae. Results A search for conserved GGDEF and EAL domains in three sequenced K. pneumoniae genomes showed that there were multiple copies of GGDEF and EAL containing proteins. Both single domain and hybrid GGDEF proteins were identified: 21 in K. pneumoniae Kp342, 18 in K. pneumoniae MGH 78578 and 17 in K. pneumoniae NTUH-K2044. The majority had only the GGDEF domain, most with the GGEEF motif, and hybrid proteins containing both GGDEF and EAL domains were also found. The I site for allosteric control was identified only in single GGDEF domain proteins and not in hybrid proteins. EAL-only proteins, containing either intact or degenerate domains, were also identified: 15 in Kp342, 15 in MGH 78578 and 10 in NTUH-K2044. Several input sensory domains and transmembrane segments were identified, which together indicate complex regulatory circuits that in many cases can be membrane associated. Conclusions The comparative analysis of proteins containing GGDEF/EAL domains in K. pneumoniae showed that most copies were shared among the three strains and that some

  15. Characterization of Siphoviridae phage Z and studying its efficacy against multidrug-resistant Klebsiella pneumoniae planktonic cells and biofilm.

    PubMed

    Jamal, Muhsin; Hussain, Tahir; Das, Chythanya Rajanna; Andleeb, Saadia

    2015-04-01

    Biofilm has many serious consequences for public health and is a major virulence factor contributing to the chronicity of infections. The aim of the current study was to isolate and characterize a bacteriophage that inhibits multidrug-resistant Klebsiella pneumonia (M) in planktonic form as well as biofilm. This phage, designated bacteriophage Z, was isolated from wastewater. Its adsorption rate to its host bacterium was significantly enhanced by MgCl2 and CaCl2. It has a wide range of pH and heat stability. From its one-step growth, latent time and burst size were determined to be 24 min and about 320 virions per cell, respectively. As analysed by transmission electron microscopy, phage Z had an icosahedral head of width 76±10 nm, length 92±14 nm and icosahedron side 38 nm, and a non-contractile tail 200±15 nm long and 14-29 nm wide. It belongs to the family Siphoviridae in the order Caudovirales. Six structural proteins ranging from 18 to 65 kDa in size were revealed by SDS-PAGE. The genome was found to comprise double-stranded DNA with an approximate size of 36 kb. Bacteria were grown in suspension and as biofilms to compare the susceptibility of both phenotypes to the phage lytic action. Phage Z was effective in reducing biofilm biomass after 24 and 48 h, showing more than twofold and threefold reduction, respectively. Biofilm cells and stationary-phase planktonic bacteria were killed at a lower rate than exponential-phase planktonic bacteria.

  16. The optimization of biohydrogen production by bacteria using residual glycerol from biodiesel synthesis.

    PubMed

    Costa, Janaina B; Rossi, Daniele M; De Souza, Elisangela A; Samios, Dimitrios; Bregalda, Fernanda; do Carmo Ruaro Peralba, Maria; Flores, Simone H; Ayub, Marco Antônio Z

    2011-01-01

    In this research the production of hydrogen by Klebsiella pneumoniae BLb01 using residual glycerol discharged from a biodiesel fuel production plant was investigated. Klebsiella pneumoniae BLb01 was isolated from a bacteria-rich sludge of an upflow anaerobic sludge blanket reactor (UASB) of a soybean processing plant. A Plackett-Burman design (P-B) and Response Surface Methodology (RSM) were employed to determine the optimal condition for enhanced hydrogen production. The maximal hydrogen production, which was 45.0 mol % and with 98% of glycerol degradation, was achieved with the optimized medium with the following composition: 30 g L(-1) glycerol; 3 g L(-1) yeast ex tract 3 g L(-1) K(2)HPO(4); 1 g L(-1) KH(2)PO(4); temperature 39°C and pH 9.0. These results show the ability of this new strain of effectively converting residual glycerol into value-added energy products.

  17. Epidemiology of Escherichia coli, Klebsiella species, and Proteus mirabilis strains producing extended-spectrum β-lactamases from clinical samples in the Kinki Region of Japan.

    PubMed

    Nakamura, Tatsuya; Komatsu, Masaru; Yamasaki, Katsutoshi; Fukuda, Saori; Miyamoto, Yugo; Higuchi, Takeshi; Ono, Tamotsu; Nishio, Hisaaki; Sueyoshi, Noriyuki; Kida, Kenji; Satoh, Kaori; Toda, Hirofumi; Toyokawa, Masahiro; Nishi, Isao; Sakamoto, Masako; Akagi, Masahiro; Nakai, Isako; Kofuku, Tomomi; Orita, Tamaki; Wada, Yasunao; Zikimoto, Takuya; Koike, Chihiro; Kinoshita, Shohiro; Hirai, Itaru; Takahashi, Hakuo; Matsuura, Nariaki; Yamamoto, Yoshimasa

    2012-04-01

    In the present study, nonduplicate, clinical isolates of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, Klebsiella spp, and Proteus mirabilis were collected during a 10-year period from 2000 to 2009 at several hospitals in the Kinki region, Japan. The detection rate of E coli markedly increased from 0.24% to 7.25%. The detection rate of Klebsiella pneumoniae increased from 0% to 2.44% and that of P mirabilis from 6.97% to 12.85%. The most frequently detected genotypes were the CTX-M9 group for E coli, the CTX-M2 group for K pneumoniae, and the CTX-M2 group for P mirabilis. E coli clone O25:H4-ST131 producing CTX-M-15, which is spreading worldwide, was first detected in 2007. The most common replicon type of E coli was the IncF type, particularly FIB, detected in 466 strains (69.7%). Of the K pneumoniae strains, 47 (55.3%) were of the IncN type; 77 P mirabilis strains (96.3%) were of the IncT type. In the future, the surveillance of various resistant bacteria, mainly ESBL-producing Enterobacteriaceae, should be expanded to prevent their spread.

  18. Pneumonia and bacteremia in a golden-headed lion tamarin (Leontopithecus chrysomelas) caused by Klebsiella pneumoniae subsp. pneumoniae during a translocation program of free-ranging animals in Brazil.

    PubMed

    Bueno, Marina G; Iovine, Renata O; Torres, Luciana N; Catão-Dias, José L; Pissinatti, Alcides; Kierulff, Maria C M; Carvalho, Vania M

    2015-05-01

    Klebsiella pneumoniae is an important emerging pathogen in humans, particularly the invasive hypermucoviscosity (HMV) phenotype. In addition, the organism is an important public health concern because of nosocomial infections and antimicrobial resistance. Nonhuman primates in captivity are susceptible to Klebsiella, particularly when a stress factor is involved. Infections vary depending on the species but can cause significant morbidity and mortality in these animals. The objective of this study was to describe a case of bronchopneumonia and bacteremia caused by Klebsiella pneumoniae in a free-ranging golden-headed lion tamarin (Leontopithecus chrysomelas) caught and maintained in quarantine during a translocation program for conservation purposes. An adult male, that had showed emaciation and apathy, was clinically examined and, despite being provided supportive therapy, died 2 days after onset of clinical signs. At postmortem examination, generalized bilateral pneumonia and pericarditis were observed. Tissue samples were fixed in 10% formalin for histology, and pulmonary tissues and cardiac blood were collected for microbiologic diagnostic procedures. Bacteria that were shown to be HMV K. pneumoniae subsp. pneumoniae strains were isolated from the pulmonary fluids and cardiac blood in pure cultures. Severe bronchopneumonia was the main pathological finding. The consequences of the confirmed presence of the HMV phenotype of K. pneumoniae subsp. pneumoniae in this wildlife species for human, animal, and ecosystem health should be determined. These results demonstrate the importance of quarantine and potential pathogen screening during wildlife translocation procedures.

  19. Bacteria isolated from amoebae/bacteria consortium

    DOEpatents

    Tyndall, R.L.

    1995-05-30

    New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

  20. Bacteria isolated from amoebae/bacteria consortium

    DOEpatents

    Tyndall, Richard L.

    1995-01-01

    New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

  1. Preparation of Membrane Models of Gram-Negative Bacteria and Their Interaction with Antimicrobial Peptides Studied by CD and NMR.

    PubMed

    Hicks, Rickey

    2017-01-01

    The antibiotic activity of antimicrobial peptides is generally derived via some type of disruption of the cell membrane(s). The most common models used to mimic the properties of bacterial membranes consist of mixtures of various zwitterionic and anionic phospholipids. This approach works reasonably well for Gram-positive bacteria. However, since the membranes of Gram-negative bacteria contain lipopolysaccharides, as well as zwitterionic and anionic phospholipids, a more complex model is required to simulate the outer membrane of Gram-negative bacteria. Herein we present a protocol for the preparation of models of the outer membranes of the Gram-negative bacteria Klebsiella pneumoniae and Pseudomonas aeruginosa. This protocol can be used to prepare models of other Gram-negative bacteria provided the strain-specific lipopolysaccharides are available.

  2. Biochemical parameters of glutamine synthetase from Klebsiella aerogenes.

    PubMed Central

    Bender, R A; Janssen, K A; Resnick, A D; Blumenberg, M; Foor, F; Magasanik, B

    1977-01-01

    The glutamine synthetase (GS) from Klebsiella aerogenes is similar to that from Escherichia coli in several respects: (i) it is repressed by high levels of ammonia in the growth medium; (ii) its biosynthetic activity is greatly reduced by adenylylation; and (iii) adenylylation lowers the pH optimum and alters the response of the enzymes to various inhibitors in the gamma-glutamyl transferase (gammaGT) assay. There are, however, several important differences: (i) the isoactivity point for the adenylylated and non-adenylylated forms in the gammaGT assay occurs at pH 7.55 in K. aerogenes and at pH 7.15 in E. coli; (ii) the non-adenylylated form of the GS from K. aerogenes is stimulated by 60 mM MgCl2 in the gammaGT assay at pH 7.15. A biosynthetic reaction assay that correlates well with number of non-adenylylated enzyme subunits, as determined by the method of Mg2+ inhibition of the gammaGT assay, is described. Finally, we have found that it is necessary to use special methods to harvest growing cells to prevent changes in the adenylylation state of GS from occurring during harvesting. PMID:14104

  3. Klebsiella pneumoniae FimK Promotes Virulence in Murine Pneumonia.

    PubMed

    Rosen, David A; Hilliard, Julia K; Tiemann, Kristin M; Todd, Elizabeth M; Morley, S Celeste; Hunstad, David A

    2016-02-15

    Klebsiella pneumoniae, a chief cause of nosocomial pneumonia, is a versatile and commonly multidrug-resistant human pathogen for which further insight into pathogenesis is needed. We show that the pilus regulatory gene fimK promotes the virulence of K. pneumoniae strain TOP52 in murine pneumonia. This contrasts with the attenuating effect of fimK on urinary tract virulence, illustrating that a single factor may exert opposing effects on pathogenesis in distinct host niches. Loss of fimK in TOP52 pneumonia was associated with diminished lung bacterial burden, limited innate responses within the lung, and improved host survival. FimK expression was shown to promote serum resistance, capsule production, and protection from phagocytosis by host immune cells. Finally, while the widely used K. pneumoniae model strain 43816 produces rapid dissemination and death in mice, TOP52 caused largely localized pneumonia with limited lethality, thereby providing an alternative tool for studying K. pneumoniae pathogenesis and control within the lung.

  4. Structure of 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae

    SciTech Connect

    Michalska, Karolina; Cuff, Marianne E.; Tesar, Christine; Feldmann, Brian; Joachimiak, Andrzej

    2011-08-01

    The crystal structure of 2-oxo-3-deoxygalactonate kinase from the De Ley–Doudoroff pathway of galactose metabolism has been determined at 2.1 Å resolution. In most organisms, efficient d-galactose utilization requires the highly conserved Leloir pathway that converts d-galactose to d-glucose 1-phosphate. However, in some bacterial and fungal species alternative routes of d-galactose assimilation have been identified. In the so-called De Ley–Doudoroff pathway, d-galactose is metabolized into pyruvate and d-glyceraldehyde 3-phosphate in five consecutive reactions carried out by specific enzymes. The penultimate step in this pathway involves the phosphorylation of 2-oxo-3-deoxygalactonate to 2-oxo-3-deoxygalactonate 6-phosphate catalyzed by 2-oxo-3-deoxygalactonate kinase, with ATP serving as a phosphoryl-group donor. Here, a crystal structure of 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae determined at 2.1 Å resolution is reported, the first structure of an enzyme from the De Ley–Doudoroff pathway. Structural comparison indicates that the enzyme belongs to the ASKHA (acetate and sugar kinases/hsc70/actin) family of phosphotransferases. The protein is composed of two α/β domains, each of which contains a core common to all family members. Additional elements introduced between conserved structural motifs define the unique features of 2-oxo-3-deoxygalactonate kinase and possibly determine the biological function of the protein.

  5. Epidemiology of Carbapenem Resistant Klebsiella pneumoniae Infections in Mediterranean Countries

    PubMed Central

    Girmenia, Corrado; Serrao, Alessandra; Canichella, Martina

    2016-01-01

    Infections by Carbapenem-Resistant Enterobacteriaceae (CRE), in particular, carbapenem-resistant Klebsiella pneumoniae (CRKp), are a significant public health challenge worldwide. Resistance to carbapenems in enterobacteriaceae is linked to different mechanisms, including the production of the various types of enzymes like KPC, VIM, IMP, NDM, and OXA-48. Despite several attempts to control the spread of these infections at the local and national level, the epidemiological situation for CRKp had worsened in the last years in the Mediterranean area. The rate and types of CRKp isolates greatly differ in the various Mediterranean countries. KPC-producing K. pneumoniae is diffused particularly in the European countries bordering the Mediterranean Sea and is endemic in Greece and Italy. On the contrary, OXA-48-producing K. pneumoniae is endemic in Turkey and Malta and diffused at inter-regional level particularly in some North African and Middle East countries. The spread of these multiresistant pathogens in the world and the Mediterranean countries has been related to various epidemiological factors including the international transfer of patients coming from endemic areas. PMID:27441063

  6. Screening haematology patients for carbapenem-resistant Klebsiella pneumoniae

    PubMed Central

    Kilgour, Elizabeth; Dunn, Caroline; Thomas, Linda; Fox, Richard; Mitchell, Lindsay; Paterson, Pamela

    2013-01-01

    Following a cluster of haematology patients with carbapenem-resistant Klebsiella pneumoniae (CRKP) septicaemia, we initiated screening for rectal carriage of CRKP and multidrug-resistant K. pneumoniae (MDRKP) in this patient group. Haematology inpatients submit a rectal swab once weekly. When plated onto chromogenic Brilliance™ UTI Agar (Oxoid), and incubated overnight with a 10 µg ertapenem disc (Oxoid), K. pneumoniae is identified and semi-automated antibiotic susceptibility testing is performed using the Vitek 2 analyser (Biomerieux). When no zone of inhibition occurs, immediate intervention through patient isolation and enhanced environmental cleaning can be instigated to control further spread while empirical antibiotic prescribing is adapted to take account of identified resistances. Over 2 years, six patients with CRKP and 20 patients with MDRKP were identified. These isolates were resistant to first-line empirical treatment choices for neutropenic sepsis and presented a clinical risk of treatment failure for sepsis post cytotoxic chemotherapy. We describe how this rectal screening methodology was developed and how the results influenced appropriate antibiotic prescribing, patient placement in single rooms and the cleaning of the ward environment to prevent person-to-person transmission of MDRKP and CRKP.

  7. Structure of 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae

    PubMed Central

    Michalska, Karolina; Cuff, Marianne E.; Tesar, Christine; Feldmann, Brian; Joachimiak, Andrzej

    2011-01-01

    In most organisms, efficient d-galactose utilization requires the highly conserved Leloir pathway that converts d-galactose to d-glucose 1-phosphate. However, in some bacterial and fungal species alternative routes of d-galactose assimilation have been identified. In the so-called De Ley–Doudoroff pathway, d-galactose is metabolized into pyruvate and d-­glyceraldehyde 3-phosphate in five consecutive reactions carried out by specific enzymes. The penultimate step in this pathway involves the phosphorylation of 2-oxo-3-deoxygalactonate to 2-oxo-3-deoxygalactonate 6-phosphate catalyzed by 2-­oxo-3-deoxygalactonate kinase, with ATP serving as a phosphoryl-group donor. Here, a crystal structure of 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae determined at 2.1 Å resolution is reported, the first structure of an enzyme from the De Ley–Doudoroff pathway. Structural comparison indicates that the enzyme belongs to the ASKHA (acetate and sugar kinases/hsc70/actin) family of phosphotransferases. The protein is composed of two α/β domains, each of which contains a core common to all family members. Additional elements introduced between conserved structural motifs define the unique features of 2-oxo-3-deoxygalactonate kinase and possibly determine the biological function of the protein. PMID:21795809

  8. Purification and properties of dihydroxyacetone kinase from Klebsiella pneumoniae.

    PubMed Central

    Johnson, E A; Burke, S K; Forage, R G; Lin, E C

    1984-01-01

    Dihydroxyacetone (DHA) kinase of Klebsiella pneumoniae, a gene product of the dha regulon responsible for fermentative dissimilation of glycerol and DHA, was purified 120-fold to a final specific activity of 10 mumol X min-1 X mg of protein-1 at 30 degrees C. The enzyme, a dimer of a 53,000 +/- 5,000-dalton polypeptide, is highly specific for DHA (Km, ca.4 microM). Glycerol is not a substrate at 1 mM and is not an inhibitor even at 100 mM. The enzyme is not inhibited by 5 mM fructose-1,6-diphosphate. Ca2+ gives a higher enzyme activity than Mg2+ as a cationic cofactor. Escherichia coli glycerol kinase acts on both glycerol and DHA and is allosterically inhibited by fructose-1,6-diphosphate. Antibodies raised against E. coli glycerol kinase cross-reacted with K. pneumoniae glycerol kinase but not with K. pneumoniae DHA kinase. Images PMID:6090436

  9. Klebsiella pneumoniae 1,3-propanediol:NAD+ oxidoreductase.

    PubMed Central

    Johnson, E A; Lin, E C

    1987-01-01

    Fermentative utilization of glycerol, a more reduced carbohydrate than aldoses and ketoses, requires the disposal of the two extra hydrogen atoms. This is accomplished by sacrificing an equal quantity of glycerol via an auxiliary pathway initiated by glycerol dehydratase. The product, 3-hydroxypropionaldehyde, is then reduced by 1,3-propanediol NAD+:oxidoreductase (1,3-propanediol dehydrogenase; EC 1.1.1.202), resulting in the regeneration of NAD+ from NADH. The pathway for the assimilation of glycerol is initiated by an NAD-linked dehydrogenase. In Klebsiella pneumoniae the two pathways are encoded by the dha regulon which is inducible only anaerobically. In this study 1,3-propanediol:NAD+ oxidoreductase was purified from cells grown anaerobically on glycerol. The enzyme was immunochemically distinct from the NAD-linked glycerol dehydrogenase and was an octamer or hexamer of a polypeptide of 45,000 +/- 3,000 daltons. When tested as a dehydrogenase, only 1,3-propanediol served as a substrate; no activity was detected with ethanol, 1-propanol, 1,2-propanediol, glycerol, or 1,4-butanediol. The enzyme was inhibited by chelators of divalent cations. An enzyme preparation inhibited by alpha,alpha'-dipyridyl was reactivated by the addition of Fe2+ or Mn2+ after removal of the chelator by gel filtration. As for glycerol dehydrogenase, 1,3-propanediol oxidoreductase is apparently inactivated by oxidation during aerobic metabolism, under which condition the enzyme becomes superfluous. Images PMID:3553154

  10. CRYSTAL STRUCTURE ANALYSIS OF A PUTATIVE OXIDOREDUCTASE FROM KLEBSIELLA PNEUMONIAE

    SciTech Connect

    Baig, M.; Brown, A.; Eswaramoorthy, S.; Swaminathan, S.

    2009-01-01

    Klebsiella pneumoniae, a gram-negative enteric bacterium, is found in nosocomial infections which are acquired during hospital stays for about 10% of hospital patients in the United States. The crystal structure of a putative oxidoreductase from K. pneumoniae has been determined. The structural information of this K. pneumoniae protein was used to understand its function. Crystals of the putative oxidoreductase enzyme were obtained by the sitting drop vapor diffusion method using Polyethylene glycol (PEG) 3350, Bis-Tris buffer, pH 5.5 as precipitant. These crystals were used to collect X-ray data at beam line X12C of the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory (BNL). The crystal structure was determined using the SHELX program and refi ned with CNS 1.1. This protein, which is involved in the catalysis of an oxidation-reduction (redox) reaction, has an alpha/beta structure. It utilizes nicotinamide adenine dinucleotide phosphate (NADP) or nicotine adenine dinucleotide (NAD) to perform its function. This structure could be used to determine the active and co-factor binding sites of the protein, information that could help pharmaceutical companies in drug design and in determining the protein’s relationship to disease treatment such as that for pneumonia and other related pathologies.

  11. Bacteria Inactivation During Lithotripsy

    NASA Astrophysics Data System (ADS)

    del Sol Quintero, María; Mora, Ulises; Gutiérrez, Jorge; Mues, Enrique; Castaño, Eduardo; Fernández, Francisco; Loske, Achim M.

    2006-09-01

    The influence of extracorporeal and intracorporeal lithotripsy on the viability of bacteria contained inside artificial kidney stones was investigated in vitro. Two different bacteria were exposed to the action of one extracorporeal shock wave generator and four intracorporeal lithotripters.

  12. Protein secretion in Pseudomonas aeruginosa: the xcpA gene encodes an integral inner membrane protein homologous to Klebsiella pneumoniae secretion function protein PulO.

    PubMed Central

    Bally, M; Ball, G; Badere, A; Lazdunski, A

    1991-01-01

    xcp mutations have pleiotropic effects on the secretion of proteins in Pseudomonas aeruginosa PAO. The nucleotide sequence of a 1.2-kb DNA fragment that complements the xcp-1 mutation has been determined. Sequence analysis shows the xcpA gene product to be a 31.8-kDa polypeptide, with a highly hydrophobic character. This is consistent with a localization in the cytoplasmic membrane in P. aeruginosa, determined after specific expression of the xcpA gene under control of the T7 phi 10 promoter. A very strong homology was found between XcpA and PulO, a membrane protein required for pullulanase secretion in Klebsiella pneumoniae. This suggests the existence of a signal sequence-dependent secretion process common to these two unrelated gram-negative bacteria. Images PMID:1898929

  13. Fatal infection in human flora-associated piglets caused by the opportunistic pathogen Klebsiella pneumoniae from an apparently healthy human donor.

    PubMed

    Wei, Hua; Shen, Jian; Pang, Xiaoyan; Ding, Dezhong; Zhang, Yan; Zhang, Baorang; Lu, Haifeng; Wang, Tingting; Zhang, Chenhong; Hua, Xiuguo; Cui, Li; Zhao, Liping

    2008-07-01

    Seventeen out of 24 human flora-associated (HFA) piglets died after oral administration of whole fecal flora from an apparently healthy human donor. The bacteria isolated from the organs of the infected piglets were identified as Klebsiella pneumoniae by bacteriological and biochemical tests and 16S rRNA gene sequence analysis. The identical K. pneumoniae strain was also isolated from the donor's fecal flora. All three neonatal piglets inoculated with K. pneumoniae from the donor's fecal flora developed severe diarrhea, with 2 eventually dying. This strongly suggests that the opportunistic pathogen K. pneumoniae from the human donor caused the fatal infection in the HFA piglets. The results underscore the importance of safety evaluation of the human donor's fecal flora for HFA piglet development.

  14. Antibiotic-producing bacteria from stag beetle mycangia.

    PubMed

    Miyashita, Atsushi; Hirai, Yuuki; Sekimizu, Kazuhisa; Kaito, Chikara

    2015-02-01

    The search for new antibiotics or antifungal agents is crucial for the chemotherapies of infectious diseases. The limited resource of soil bacteria makes it difficult to discover such new drug candidate. We, therefore, focused on another bacterial resource than soil bacteria, the microbial flora of insect species. In the present study, we isolated 40 strains of bacteria and fungi from the mycangia of three species of stag beetle, Dorcus hopei binodulosus, Dorcus rectus, and Dorcus titanus pilifer. We identified those species with their ribosomal DNA sequences, and revealed that Klebsiella spp. are the most frequent symbiont in the stag beetle mycangia. We examined whether these microorganisms produce antibiotics against a Gram-negative bacterium, Escherichia coli, a Gram-positive bacterium, Staphylococcus aureus, or a fungus, Cryptococcus neoformans. Culture supernatants from 33, 29, or 18 strains showed antimicrobial activity against E. coli, S. aureus, or C. neoformans, respectively. These findings suggest that bacteria present in the mycangia of stag beetles are useful resources for screening novel antibiotics.

  15. Insect Antimicrobial Peptide Complexes Prevent Resistance Development in Bacteria

    PubMed Central

    Chernysh, Sergey; Gordya, Natalia; Suborova, Tatyana

    2015-01-01

    In recent decades much attention has been paid to antimicrobial peptides (AMPs) as natural antibiotics, which are presumably protected from resistance development in bacteria. However, experimental evolution studies have revealed prompt resistance increase in bacteria to any individual AMP tested. Here we demonstrate that naturally occurring compounds containing insect AMP complexes have clear advantage over individual peptide and small molecule antibiotics in respect of drug resistance development. As a model we have used the compounds isolated from bacteria challenged maggots of Calliphoridae flies. The compound isolated from blow fly Calliphora vicina was found to contain three distinct families of cell membrane disrupting/permeabilizing peptides (defensins, cecropins and diptericins), one family of proline rich peptides and several unknown antimicrobial substances. Resistance changes under long term selective pressure of the compound and reference antibiotics cefotaxime, meropenem and polymyxin B were tested using Escherichia coli, Klebsiella pneumonia and Acinetobacter baumannii clinical strains. All the strains readily developed resistance to the reference antibiotics, while no signs of resistance growth to the compound were registered. Similar results were obtained with the compounds isolated from 3 other fly species. The experiments revealed that natural compounds containing insect AMP complexes, in contrast to individual AMP and small molecule antibiotics, are well protected from resistance development in bacteria. Further progress in the research of natural AMP complexes may provide novel solutions to the drug resistance problem. PMID:26177023

  16. Fungi outcompete bacteria under increased uranium concentration in culture media.

    PubMed

    Mumtaz, Saqib; Streten-Joyce, Claire; Parry, David L; McGuinness, Keith A; Lu, Ping; Gibb, Karen S

    2013-06-01

    As a key part of water management at the Ranger Uranium Mine (Northern Territory, Australia), stockpile (ore and waste) runoff water was applied to natural woodland on the mine lease in accordance with regulatory requirements. Consequently, the soil in these Land Application Areas (LAAs) presents a range of uranium concentrations. Soil samples were collected from LAAs with different concentrations of uranium and extracts were plated onto LB media containing no (0 ppm), low (3 ppm), medium (250 ppm), high (600 ppm) and very high (1500 ppm) uranium concentrations. These concentrations were similar to the range of measured uranium concentrations in the LAAs soils. Bacteria grew on all plates except for the very high uranium concentrations, where only fungi were recovered. Identifications based on bacterial 16S rRNA sequence analysis showed that the dominant cultivable bacteria belonged to the genus Bacillus. Members of the genera Paenibacillus, Lysinibacillus, Klebsiella, Microbacterium and Chryseobacterium were also isolated from the LAAs soil samples. Fungi were identified by sequence analysis of the intergenic spacer region, and members of the genera Aspergillus, Cryptococcus, Penicillium and Curvularia were dominant on plates with very high uranium concentrations. Members of the Paecilomyces and Alternaria were also present but in lower numbers. These findings indicate that fungi can tolerate very high concentrations of uranium and are more resistant than bacteria. Bacteria and fungi isolated at the Ranger LAAs from soils with high concentrations of uranium may have uranium binding capability and hence the potential for uranium bioremediation.

  17. Klebsiella spp as a 1, 3-propanediol producer: the metabolic engineering approach.

    PubMed

    Celińska, E

    2012-09-01

    Klebsiella spp are one of the best natural producers of 1,3-propanediol (1,3-PD). However, their usage in the biotechnological production of the diol is limited, since the species belong to the second hazard group. Nevertheless, multiple advantageous traits of Klebsiella spp justify the international effort devoted to develop a biotechnological process of 1,3-PD production with these microorganisms. Apart from the process engineering approach aiming at improvement of 1,3-PD production by Klebsiella spp, plethora of metabolic engineering approaches have been reported. Different strategies have been undertaken to genetically improve Klebsiella strains and provide them with the ability to synthesize 1,3-PD more efficiently. These include over-expression of both homologous and heterologous genes of the 1,3-PD synthesis pathway, protein and cofactor engineering, deletion of the genes involved in by-products formation. This review provides an overview of the initial and most recent reports on the metabolic engineering of Klebsiella spp with the aim of improvement of 1,3-PD biosynthesis.

  18. Pleuritis and suppurative pneumonia associated with a hypermucoviscosity phenotype of Klebsiella pneumoniae in California sea lions (Zalophus californianus).

    PubMed

    Jang, Spencer; Wheeler, Liz; Carey, Roberta B; Jensen, Bette; Crandall, Claudia M; Schrader, Kimmi N; Jessup, David; Colegrove, Kathleen; Gulland, Frances M D

    2010-02-24

    The aim of this study is to document the isolation of a hypermucoviscosity (HMV) phenotype of Klebsiella pneumoniae from 25 cases of suppurative pneumonia and pleuritis and two cases of abscesses in California sea lions (Zalophus californianus) from the central California coast, representing the first report of this zoonotic pathogen from the marine environment and only the second report in non-humans. Animals died 2h to 4 days after first being observed sick on beaches. Clinical signs varied from dyspnoea to coma. Gross post-mortem examination of 25 cases revealed fibrinous pleuritis, copious pus in the pleural cavity and suppurative bronchopneumonia. K. pneumoniae isolates obtained from lung and pleural swabs and the hepatic and subcuticular abscesses were highly mucoid on blood agar culture media and were positive to the "string test". Twenty-one of the 27 isolates were examined by PCR and all were positive for rmpA and K2wyz and negative for K1magA genes. Although pneumonia and pleuritis have previously commonly been observed in marine mammals, their association with pure cultures of a zoonotic bacteria, K. pneumoniae HMV phenotype, has not. This report provides further evidence of the role marine mammals play as sentinels of health risks to humans from coastal waters.

  19. Identification of a capsular variant and characterization of capsular acetylation in Klebsiella pneumoniae PLA-associated type K57

    PubMed Central

    Hsu, Chun-Ru; Liao, Chun-Hsing; Lin, Tzu-Lung; Yang, Han-Ru; Yang, Feng-Ling; Hsieh, Pei-Fang; Wu, Shih-Hsiung; Wang, Jin-Town

    2016-01-01

    Klebsiella pneumoniae can cause community-acquired pyogenic liver abscess (PLA). Capsular polysaccharide (CPS) is important for its virulence. Among 79 capsular (K) types discovered thus far, K57 is often associated with PLA. Here, we report the identification of a K57 variant. Cps gene locus sequencing revealed differences between the K57 reference strain 4425/51 (Ref-K57) and a variant, the PLA isolate A1142. While Ref-K57 cps contained orf13 encoding a putative acetyltransferase, the insertion of a putative transposase-encoding gene at this position was detected in A1142. This variation was detected in other K57 clinical strains. Biochemical analyses indicated that A1142 was deficient in CPS acetylation. Genetic replacement and complementation verified that orf13 was responsible for CPS acetylation. Acetylation increased CPS immunoreactivity to antiserum and enhanced K. pneumoniae induction of pro-inflammatory cytokines through JNK and MAPK signaling. While acetylation diminished the serum resistance of bacteria, it promoted adhesion to intestinal epithelial cells possibly via increasing production of type I fimbriae. In conclusion, acetylation-mediated capsular variation in K57 was observed. Capsular acetylation contributed to the variety and antigenic diversity of CPS, influenced its biological activities, and was involved in K. pneumoniae-host interactions. These findings have implications for vaccine design and pathogenicity of K. pneumoniae. PMID:27550826

  20. Construction of intergeneric hybrids using bacteriophage P1CM: transfer of the Klebsiella aerogenes ribitol dehydrogenase gene to Escherichia coli.

    PubMed

    Rigby, P W; Gething, M J; Hartley, B S

    1976-02-01

    Study of many of the interesting properties of Klebsiella aerogenes is limited by the lack of a well-characterized genetic system for this organism. Our investigations of the evolution of the enzyme ribitol dehydrogenase (EC 1.1.1.56) in K. aerogenes would be greatly facilitated by the availability of such a system, and we here report two approaches to developing one. We have isolated mutants sensitive to the coliphage P1, which will efficiently tranduce genetic markers between such sensitive strains and which will thus make detailed mapping studies possible. Derivatives of K. aerogenes lysogenic for P1 can be readily isolated by using the specialized transducing particle P1CMclr100. Bacteria lysogenic for this phage are chloramphenicol resistant and temperature sensitive. Phage particles produced by temperature induction of such lysogens can be used to transfer K. aerogenes genes to the natural host of P1 phage. Escherichia coli. We have used this method to prepare derivatives of E. coli K-12 carrying the K. aerogenes genes conferring the ability to metabolize the pentitols ribitol and D-arabitol. We have shown that these E. coli-K. aerogenes hybrids synthesize a ribitol dehydrogenase with the properties of the K. aerogenes enzyme and have mapped the position of the transferred gene on the E. coli chromosome. The ramifications of this methodology are discussed.

  1. Effect of antimicrobial peptides on colistin-susceptible and colistin-resistant strains of Klebsiella pneumoniae and Enterobacter asburiae.

    PubMed

    Kádár, Béla; Kocsis, Béla; Kristof, Katalin; Tóth, Ákos; Szabó, Dóra

    2015-12-01

    In this study susceptibility to different antimicrobial peptides was investigated on colistin-susceptible and colistin-resistant identical pulsotype strains of KPC-2 producing Klebsiella pneumoniae ST258 as well as colistin-susceptible and colistin-resistant Enterobacter asburiae strains isolated from clinical samples. In our test, bacteria were exposed to 50 mg/ml lactoferrin, lysozyme and protamine - cationic antimicrobial peptides belonging to innate immune system and having structural similarity to polymyxins - in separate reactions. After 18 hours incubation of colonies were counted. 40% of colistin-resistant K. pneumoniae strains and 97% of colistin-susceptible counterpart strains were lysed by protamine whereas 87% and 100% colony forming unit decrease by lysozyme was seen, respectively. In the case of colistin-resistant E. asburiae strains 1 log10 cell count increase were observed after treatment with lysozyme and 1.56 log10 after lactoferrin exposure compared to the initial number whereas the colistin-susceptible showed no relevant cell count increase. Our findings suggest that acquired colistin-resistance in Enterobacteriaceae is associated with tolerance against antimicrobial peptides.

  2. Occurrence of bacteriophages infecting Aeromonas, Enterobacter, and Klebsiella in water and association with contamination sources in Thailand.

    PubMed

    Wangkahad, Bencharong; Bosup, Suchada; Mongkolsuk, Skorn; Sirikanchana, Kwanrawee

    2015-06-01

    The co-residence of bacteriophages and their bacterial hosts in humans, animals, and environmental sources directed the use of bacteriophages to track the origins of the pathogenic bacteria that can be found in contaminated water. The objective of this study was to enumerate bacteriophages of Aeromonas caviae (AecaKS148), Enterobacter sp. (EnspKS513), and Klebsiella pneumoniae (KlpnKS648) in water and evaluate their association with contamination sources (human vs. animals). Bacterial host strains were isolated from untreated wastewater in Bangkok, Thailand. A double-layer agar technique was used to detect bacteriophages. All three bacteriophages were detected in polluted canal samples, with likely contamination from human wastewater, whereas none was found in non-polluted river samples. AecaKS148 was found to be associated with human fecal sources, while EnspKS513 and KlpnKS648 seemed to be equally prevalent in both human and animal fecal sources. Both bacteriophages were also present in polluted canals that could receive contamination from other fecal sources or the environment. In conclusion, all three bacteriophages were successfully monitored in Bangkok, Thailand. This study provided an example of bacteriophages for potential use as source identifiers of pathogen contamination. The results from this study will assist in controlling sources of pathogen contamination, especially in developing countries.

  3. S-thanatin functionalized liposome potentially targeting on Klebsiella pneumoniae and its application in sepsis mouse model

    PubMed Central

    Fan, Xiaobo; Fan, Juxiang; Wang, Xiyong; Wu, Pengpeng; Wu, Guoqiu

    2015-01-01

    S-thanatin (Ts) was a short antimicrobial peptide with selective antibacterial activity. In this study, we aimed to design a drug carrier with specific bacterial targeting potential. The positively charged Ts was modified onto the liposome surface by linking Ts to the constituent lipids via a PEG linker. The benefits of this design were evaluated by preparing a series of liposomes and comparing their biological effects in vitro and in vivo. The particle size and Zeta potential of the constructed liposomes were measured with a Zetasizer Nano ZS system and a confocal laser scanning microscope. The in vitro drug delivery potential was evaluated by measuring the cellular uptake of encapsulated levofloxacin using HPLC. Ts-linked liposome or its conjugates with quantum dots favored bacterial cells, and increased the bacterial uptake of levofloxacin. In antimicrobial assays, the Ts and levofloxacin combination showed a synergistic effect, and Ts-LPs-LEV exhibited excellent activity against the quality control stain Klebsiella pneumoniae ATCC 700603 and restored the susceptibility of multidrug-resistant K. pneumoniae clinical isolates to levofloxacin in vitro. Furthermore, Ts-LPs-LEV markedly reduced the lethality rate of the septic shock and resulted in rapid bacterial clearance in mouse models receiving clinical multidrug resistant (MDR) isolates. These results suggest that the Ts-functionalized liposome may be a promising antibiotic delivery system for clinical infectious disorders caused by MDR bacteria, in particular the sepsis related diseases. PMID:26578959

  4. Effects of the hindlimb-unloading model of spaceflight conditions on resistance of mice to infection with Klebsiella pneumoniae

    NASA Technical Reports Server (NTRS)

    Belay, Tesfaye; Aviles, Hernan; Vance, Monique; Fountain, Kimberly; Sonnenfeld, Gerald

    2002-01-01

    BACKGROUND: It has been well documented in several studies that many immunologic parameters are altered in experimental animals and human subjects who have flown in space. However, it is not fully known whether these immunologic changes could result in increased susceptibility to infection. Hindlimb (antiorthostatic) unloading of rodents has been used successfully to simulate some of the effects of spaceflight on physiologic systems. OBJECTIVE: The objective of this study was to determine the effect of hindlimb unloading on the outcome of Klebsiella pneumoniae infection in mice. METHODS: Hindlimb-unloaded, hindlimb-restrained, and control mice were intraperitoneally infected with one 50% lethal dose of K pneumoniae 2 days after suspension. Mortality and bacterial load in several organs were compared among the groups. RESULTS: Unloaded mice showed significantly increased mortality and reduced mean time to death compared with that seen in the control groups. Kinetics of bacterial growth with smaller infective doses revealed that control mice were able to clear bacteria from the organs after 30 hours. In contrast, unloaded mice had continued bacterial growth at the same time point. CONCLUSION: The results of this study suggest that hindlimb unloading might enhance the dissemination of K pneumoniae, leading to increased mortality. The complex physiologic changes observed during hindlimb unloading, including stress, have a key role in the pathophysiology of this infection.

  5. Community spread of extended-spectrum β-lactamase-producing Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis: a long-term study in Japan.

    PubMed

    Chong, Yong; Shimoda, Shinji; Yakushiji, Hiroko; Ito, Yoshikiyo; Miyamoto, Toshihiro; Kamimura, Tomohiko; Shimono, Nobuyuki; Akashi, Koichi

    2013-07-01

    Community-acquired infections caused by extended-spectrum β-lactamase (ESBL)-producing bacteria, particularly CTX-M-producing Escherichia coli, are a rising concern worldwide. There are few data from Japan on the acquisition of ESBLs in the community or the influx of these bacteria into hospitals. Therefore, we examined the prevalence of ESBL carriage in outpatients, in order to estimate the spread of ESBLs in community settings. We analysed bacterial isolates from outpatient samples at our institution over a 9-year period from 2003 to 2011, with respect to epidemiological data on ESBL-producing bacteria and their genotypic features. Out of 5137 isolates, 321 (6.3 %) were ESBL producers, including E. coli, Klebsiella pneumoniae and Proteus mirabilis. The detection rates of the ESBL-producing isolates gradually increased and reached 14.3, 8.7 and 19.6 % for E. coli, K. pneumoniae and P. mirabilis strains, respectively, in 2011. Genotyping analysis showed that many of the strains produced multiple β-lactamases, including TEM, SHV and CTX-M, rather than just CTX-M. The CTX-M-9 group was dominant among the CTX-M genotypes; further, the CTX-M-1 and M-2 groups were also detected (~30 %). This is believed to be the first report from Japan showing a definite increase in ESBL detection in outpatients. In addition, our findings suggest the simultaneous community spread of diverse ESBL genotypes, not an expansion of particular ESBL genes.

  6. Antibodies to Klebsiella pneumoniae, Escherichia coli and Proteus mirabilis in the sera of ankylosing spondylitis patients with/without iritis and enthesitis.

    PubMed

    Mäki-Ikola, O; Lehtinen, K; Toivanen, P; Granfors, K

    1995-05-01

    IgM, IgG and IgA class serum antibodies against the whole Klebsiella pneumoniae, Escherichia coli and Proteus mirabilis bacteria, as well as against K. pneumoniae and E. coli lipopolysaccharides (LPSs) were studied earlier in the sera of 98 patients with ankylosing spondylitis (AS) and in 102 healthy blood donors by enzyme immunoassay. In this study the patients were divided into groups according to the clinical picture, i.e. presence or absence of iritis and enthesitis. The previous major finding of increased IgA class antibody levels against the whole K. pneumoniae bacteria in AS patients when compared to the healthy controls was not specifically associated with any single patient group in the present study. However, the patients with iritis had higher levels of IgA class antibodies to LPS of K. pneumoniae and E. coli when compared to the patients without iritis. In addition, the patients without enthesitis had higher level of IgG class antibodies against whole K. pneumoniae bacteria compared to the patients with enthesitis. The increased IgA class antibody levels against K. pneumoniae and E. coli LPS in AS patients with iritis may reflect an inflammatory process in the gut area. Furthermore, there were certain other differences in the immunological parameters between the AS patients with and without iritis or enthesitis and the possibility that they reflect different mechanisms involved in the disease processes cannot be excluded.

  7. Properties of Klebsiella phage P13 and associated exopolysaccharide depolymerase

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Li, Guiyang; Mo, Zhaolan; Chai, Zihan; Shang, Anqi; Mou, Haijin

    2013-11-01

    The bacteriophage P13 that infects Klebsiella serotype K13 contains a heat-stable depolymerase capable of effective degradation of exopolysaccharide (EPS) produced by this microorganism. In this study, the titer of phage P13, initially 2.0 × 107 pfu mL-1, was found increasing 20 min after infection and reached 5.0 × 109 pfu mL-1 in 60 min. Accordingly, the enzyme activity of depolymerase approached the maximum 60 min after infection. Treatment at 70°C for 30 min inactivated all the phage, but retained over 90% of the depolymerase activity. Addition of acetone into the crude phage lysate led to precipitation of the protein, with a marked increase in bacterial EPS degradation activity and a rapid drop in the titer of phage. After partial purification by acetone precipitation and ultrafiltration centrifugation, the enzyme was separated from the phage particles, showing two components with enzyme activity on Q-Sepharose Fast Flow. The soluble enzyme had an optimum degradation activity at 60°C and pH 6.5. Transmission electron microscopy demonstrated that the phage P13 particles were spherical with a diameter of 50 nm and a short stumpy tail. It was a doublestrand DNA virus consisting of a nucleic acid molecule of 45976 bp. This work provides an efficient purification operation including thermal treatment and ultrafiltration centrifugation, to dissociate depolymerase from phage particles. The characterization of phage P13 and associated EPS depolymerase is beneficial for further application of this enzyme.

  8. The nac (nitrogen assimilation control) gene from Klebsiella aerogenes.

    PubMed Central

    Schwacha, A; Bender, R A

    1993-01-01

    The Klebsiella aerogenes nac gene, whose product is necessary for nitrogen regulation of a number of operons, was identified and its DNA sequence determined. The nac sequence predicted a protein a 305 amino acids with a strong similarity to members of the LysR family of regulatory proteins, especially OxyR from Escherichia coli. Analysis of proteins expressed in minicells showed that nac is a single-gene operon whose product has an apparent molecular weight of about 32 kDa as measured in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Immediately downstream from nac is a two-gene operon, the first gene of which encodes another member of the LysR family. Upstream from nac is a tRNAAsn gene transcribed divergently from nac. About 60 bp upstream from the nac open reading frame lies a sequence nearly identical to the consensus for sigma 54-dependent promoters, with the conserved GG and GC nucleotides at -26 and -14 relative to the start of transcription. About 130 bp farther upstream (at -153 relative to the start of transcription) is a sequence nearly identical to the transcriptional activator NTRC-responsive enhancer consensus. Another weaker NTRC-binding site is located adjacent to this site (at -133 relative to the start of transcription). Thus, we propose that nac is transcribed by RNA polymerase carrying sigma 54 in response to the nitrogen regulatory (NTR) system. A transposon located between the promoter and the nac ORF prevented NTR-mediated expression of nac, supporting this identification of the promoter sequence. The insertion of over 5 kb of transposon DNA between the enhancer and its target promoter had only a weak effect on enhancer-mediated regulation, suggesting that enhancers may be able to act at a considerable distance on the bacterial chromosome. Images PMID:8458853

  9. Emergence of OXA-48-Producing Klebsiella pneumoniae in Taiwan.

    PubMed

    Ma, Ling; Wang, Jann-Tay; Wu, Tsu-Lan; Siu, L Kristopher; Chuang, Yin-Ching; Lin, Jung-Chung; Lu, Min-Chi; Lu, Po-Liang

    2015-01-01

    The isolation of OXA-48-producing Enterobacteriaceae has increased dramatically in Mediterranean countries in the past 10 years, and has recently emerged in Asia. Between January 2012 and May 2014, a total of 760 carbapenem non-susceptible Klebsiella pneumoniae (CnSKP) isolates were collected during a Taiwan national surveillance. Carbapenemases were detected in 210 CnSKP isolates (27.6%), including 162 KPC-2 (n = 1), KPC-3, KPC-17, and NDM-1 (n = 1 each), OXA-48 (n = 4), IMP-8 (n = 18), and VIM-1 (n = 24). The four blaOXA-48 CnSKP isolates were detected in late 2013. Herein we report the emergence OXA-48-producing K. pneumoniae isolates in Taiwan. PFGE analysis revealed that the four isolates belonged to three different pulsotypes. Three isolates harboured blaCTX-M genes and belonged to MLST type ST11. In addition, the plasmids belonged to the incompatibility group, IncA/C. One isolate belonged to ST116 and the plasmid incompatibility group was non-typeable. The sequence upstream of the blaOXA-48 gene in all four isolates was identical to pKPOXA-48N1, a blaOXA-48-carrying plasmid. This is the first report of OXA-48-producing Enterobacteriaceae in Taiwan and the second report to identify blaOXA-48 on an IncA/C plasmid in K. pneumoniae. Given that three isolates belong to the same pandemic clone (ST11) and possess the IncA/C plasmid and similar plasmid digestion profile that indicated the role of clonal spread or plasmid for dissemination of blaOXA-48 gene, the emergence of OXA-48-producing K. pneumoniae in Taiwan is of great concern.

  10. CXCR1/CXCR2 antagonism is effective in pulmonary defense against Klebsiella pneumoniae infection.

    PubMed

    Wei, Jing; Peng, Jing; Wang, Bing; Qu, Hong; Wang, Shiyi; Faisal, Aziz; Cheng, Jia-Wei; Gordon, John R; Li, Fang

    2013-01-01

    Klebsiella pneumoniae-associated pathology is largely mediated by neutrophilic inflammation. In this study, we administered Klebsiella pneumoniae to experimental guinea pig groups and the ELR-CXC chemokine antagonist CXCL8(3-72), ceftazidime, and dexamethasone to different groups, respectively. After 24 h, we assessed the animal's pulmonary inflammatory levels, including gross histopathology, airway neutrophilia, lung myeloperoxidase levels, expressions of CXCL8 and TNF, and airway bacterial loads. Compared with ceftazidime and dexamethasone treatments, the administration of the ELR-CXC chemokine antagonist CXCL8(3-72) alone was more effective than other methods, although it did not markedly attenuate the bacterial load. These results suggest new methods for the treatment of Klebsiella pneumoniae pathology.

  11. Fatal cross infection by carbapenem resistant Klebsiella in two liver transplant recipients

    PubMed Central

    Mathers, Amy J.; Cox, Heather L.; Bonatti, Hugo; Kitchel, Brandon; Brassinga, Ann Karen C.; Wispelwey, Brian; Sawyer, Robert G.; Pruett, Timothy L.; Hazen, Kevin C.; Patel, Jean B.; Sifri, Costi D.

    2010-01-01

    Members of the family Enterobacteriaceae including Klebsiella have re-emerged as major pathogens in solid organ transplantation. The recent appearance and dissemination of carbapenemase-producing Enterobacteriaceae in Europe and the northeastern United States represents a major challenge to the treatment of enteric gram-negative bacterial infections in immunocompromised patients; however, few reports have detailed the outcomes of such infections. Here we report two cases of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella infections in orthotopic liver transplant recipients, which were the index case and initial secondary case for an outbreak of KPC-producing Enterobacteriaceae in our institution. In both instances, the pathogens were initially misidentified as being carbapenem sensitive, the infections recurred after cessation of directed therapy, and the patients ultimately succumbed to their infections. PMID:19254325

  12. Gastrointestinal colonization with ESBL-producing Klebsiella in preterm babies--is vancomycin to blame?

    PubMed

    Ofek-Shlomai, N; Benenson, S; Ergaz, Z; Peleg, O; Braunstein, R; Bar-Oz, B

    2012-04-01

    In this study, we examine the possible association between treatment with vancomycin and colonization with extended-spectrum beta-lactamase (ESBL)-producing Klebsiella in our neonatal intensive care unit (NICU). Variables compared between newborns which developed rectal colonization and those who did not include: gestational age, birth weight, gender, and total length of hospital stay until positive stool culture or discharge, treatment with vancomycin, and positive blood culture for coagulase-negative Staphylococcus. We found that lower birth weight, younger gestational age, and treatment with vancomycin were statistically significant risk factors for gastrointestinal colonization with ESBL-producing Klebsiella. When applying a multivariate model, treatment with vancomycin, both for a full 10-day course and for a short 3-day empirical treatment, remained statistically significant. Treatment with vancomycin is a risk factor for gastrointestinal colonization with ESBL-producing Klebsiella in premature babies.

  13. Silent destruction of aortic and mitral valve by Klebsiella pneumoniae endocarditis

    PubMed Central

    Srinivas, K H; Sharma, Rajni; Agrawal, Navin; Manjunath, C N

    2013-01-01

    Klebsiella endocarditis rarely affects the native valve especially in the immunocompromised and the elderly. We report a case of Klebsiella endocarditis in a 60-year-old man who had a nidus of infection on the aortic valve which led to severe aortic regurgitation. This possibly spread to the anterior mitral leaflet (AML) leading to AML perforation therefore causing moderate mitral regurgitation. The reason for this suspicion was that there was perforation of the AML in the absence of vegetation. Noteworthy is that he was asymptomatic apart from generalised fatigue. This case draws our attention to the nature of Klebsiella valvular affection due to the fact that it had bitten the aortic and mitral valve silently and compelled the patient to undergo double valve replacement without having a prolonged duration of symptomatic illness thereby calling for high suspicion especially in individuals in the extremes of ages where the symptoms are less-guiding than the signs. PMID:24057412

  14. Construction and expression of recombinant plasmids encoding type 1 fimbriae of a urinary Klebsiella pneumoniae isolate.

    PubMed Central

    Purcell, B K; Clegg, S

    1983-01-01

    The type 1 fimbriae of Klebsiella pneumoniae have been implicated as important virulence factors in mediating Klebsiella urinary infections. The chromosomally encoded fimbrial genes were cloned by a cosmid cloning technique. Further subcloning was performed with the cloning vehicles pBR322 and pACYC184, and a recombinant plasmid containing the fimbrial genes was constructed. After transformation by this plasmid, both Escherichia coli and Salmonella typhimurium were shown to express fimbriae which reacted with Klebsiella fimbrial antiserum. The approximate location of the relevant genes on the chimeric plasmid was determined by insertion of the transposable element Tn5. Hemagglutination-negative phenotypes were used to estimate the minimum size of the DNA fragment necessary to encode fimbrial biosynthesis and expression. The size of the coding region of this fragment was found to be 5.5 kilobase pairs. PMID:6132874

  15. Longitudinal Characterization of Acinetobacter baumannii-calcoaceticus Complex, Klebsiella pneumoniae, and Methicillin-Resistant Staphylococcus aureus Colonizing and Infecting Combat Casualties

    DTIC Science & Technology

    2012-01-01

    Brief report Longitudinal characterization of Acinetobacter baumannii-calcoaceticus complex, Klebsiella pneumoniae , and methicillin-resistant...resistant Acinetobacter baumannii-calcoaceticus complex Klebsiella pneumoniae Methicillin-resistant Staphylococcus aureus MRSA Drug-resistant...Acinetobacter baumannii-calcoaceticus complex, Klebsiella pneumoniae , and methicillin- resistant Staphylococcus aureus colonize and infect combat casualties

  16. In Silico Analysis of Usher Encoding Genes in Klebsiella pneumoniae and Characterization of Their Role in Adhesion and Colonization

    PubMed Central

    Khater, Fida; Balestrino, Damien; Charbonnel, Nicolas; Dufayard, Jean François; Brisse, Sylvain; Forestier, Christiane

    2015-01-01

    Chaperone/usher (CU) assembly pathway is used by a wide range of Enterobacteriaceae to assemble adhesive surface structures called pili or fimbriae that play a role in bacteria-host cell interactions. In silico analysis revealed that the genome of Klebsiella pneumoniae LM21 harbors eight chromosomal CU loci belonging to γκп and ϭ clusters. Of these, only two correspond to previously described operons, namely type 1 and type 3-encoding operons. Isogenic usher deletion mutants of K. pneumoniae LM21 were constructed for each locus and their role in adhesion to animal (Intestine 407) and plant (Arabidopsis thaliana) cells, biofilm formation and murine intestinal colonization was investigated. Type 3 pili usher deleted mutant was impaired in all assays, whereas type 1 pili usher deleted mutant only showed attenuation in adhesion to plant cells and in intestinal colonization. The LM21ΔkpjC mutant was impaired in its capacity to adhere to Arabidopsis cells and to colonize the murine intestine, either alone or in co-inoculation experiments. Deletion of LM21kpgC induced a significant decrease in biofilm formation, in adhesion to animal cells and in colonization of the mice intestine. The LM21∆kpaC and LM21∆kpeC mutants were only attenuated in biofilm formation and the adhesion abilities to Arabidopsis cells, respectively. No clear in vitro or in vivo effect was observed for LM21∆kpbC and LM21∆kpdC mutants. The multiplicity of CU loci in K. pneumoniae genome and their specific adhesion pattern probably reflect the ability of the bacteria to adhere to different substrates in its diverse ecological niches. PMID:25751658

  17. Multiplex real-time PCR assay for detection and classification of Klebsiella pneumoniae carbapenemase gene (bla KPC) variants.

    PubMed

    Chen, Liang; Mediavilla, José R; Endimiani, Andrea; Rosenthal, Marnie E; Zhao, Yanan; Bonomo, Robert A; Kreiswirth, Barry N

    2011-02-01

    Carbapenem resistance mediated by plasmid-borne Klebsiella pneumoniae carbapenemases (KPC) is an emerging problem of significant clinical importance in Gram-negative bacteria. Multiple KPC gene variants (bla(KPC)) have been reported, with KPC-2 (bla(KPC-2)) and KPC-3 (bla(KPC-3)) associated with epidemic outbreaks in New York City and various international settings. Here, we describe the development of a multiplex real-time PCR assay using molecular beacons (MB-PCR) for rapid and accurate identification of bla(KPC) variants. The assay consists of six molecular beacons and two oligonucleotide primer pairs, allowing for detection and classification of all currently described bla(KPC) variants (bla(KPC-2) to bla(KPC-11)). The MB-PCR detection limit was 5 to 40 DNA copies per reaction and 4 CFU per reaction using laboratory-prepared samples. The MB-PCR probes were highly specific for each bla(KPC) variant, and cross-reactivity was not observed using DNA isolated from several bacterial species. A total of 457 clinical Gram-negative isolates were successfully characterized by our MB-PCR assay, with bla(KPC-3) and bla(KPC-2) identified as the most common types in the New York/New Jersey metropolitan region. The MB-PCR assay described herein is rapid, sensitive, and specific and should be useful for understanding the ongoing evolution of carbapenem resistance in Gram-negative bacteria. As novel bla(KPC) variants continue to emerge, the MB-PCR assay can be modified in response to epidemiologic developments.

  18. [A new rapid antibiotic susceptibility test for enteric bacteria using a color change method].

    PubMed

    Kocagöz, T; Hayran, M; Kocagöz, S

    1988-01-01

    The rapid antibiotic susceptibility tests that have been developed so far cannot be used in daily work, because of their many difficulties and disadvantages. We have developed a new antibiotic susceptibility test for enteric bacteria which gives the result in 4 hours, easy to perform and inexpensive. This method depends upon the mechanism which detects the acid formed by the bacteria, by the change of the color of the pH indicator in the medium. The susceptibility of 110 different isolates of enteric bacteria (E. coli, Klebsiella, Salmonella, Shigella, Proteus, Enterobacter) to ampicillin, amikacin, trimethoprim-sulfamethoxazole, cephradine, cefazolin, erythromycin, gentamicin, and ofloxacin is examined by this new "Rapid Color Change Test" and disc diffusion method. For most organisms tested, there was a good correlation between the results of the two methods. The overall agreement is found to be 91.43%.

  19. Inactivation of bacteria via photosensitization of vitamin K3 by UV-A light.

    PubMed

    Xu, Fei; Vostal, Jaroslav G

    2014-09-01

    This study investigated inactivation of bacteria with ultraviolet light A irradiation in combination with vitamin K3 as a photosensitizer. Six bacteria including Bacillus cereus, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Klebsiella pneumoniae, and Escherichia coli suspended in vitamin K3 aqueous solution were exposed to ultraviolet light A. Five of six bacteria, with the exception of Pseudomonas aeruginosa, were reduced by eight logs with 1600 μM of vitamin K3 and 5.8 J cm(-2) UV-A irradiation. Pseudomonas aeruginosa was reduced by four logs under these conditions. Reactive oxygen species including singlet oxygen, hydroxyl radical and superoxide anion radical were generated in vitamin K3 aqueous solution under UV-A irradiation. These results suggest that vitamin K3 and UV-A irradiation may be effective for bacterial inactivation in environmental and medical applications.

  20. Harvesting energy of interaction between bacteria and bacteriophage in a membrane-less fuel cell.

    PubMed

    Gupta, Ragini; Bekele, Wasihun; Ghatak, Animangsu

    2013-11-01

    When a fuel and oxidant flow in laminar contact through a micro-fluidic channel, a sharp interface appears between the two liquids, which eliminate the need of a proton exchange membrane. This principle has been used to generate potential in a membrane-less fuel cell. This study use such a cell to harvest energy of interaction between a bacteria having negative charge on its surface and a bacteriophage with positive and negative charges on its tail and head, respectively. When Klebsiella pneumoniae (Kp6) and phage (P-Kp6) are pumped through a fuel cell fitted with two copper electrodes placed at its two sides, interaction between these two charged species at the interface results in a constant open circuit potential which varies with concentration of charged species but gets generated for both specific and non-specific bacteria and phage system. Oxygenation of bacteria or phage however diminishes the potential unlike in conventional microbial fuel cells.

  1. Diverse endophytic bacteria isolated from a leguminous tree Conzattia multiflora grown in Mexico.

    PubMed

    Wang, En Tao; Tan, Zhi Yuan; Guo, Xian Wu; Rodríguez-Duran, Rolando; Boll, Gisela; Martínez-Romero, Esperanza

    2006-10-01

    Conzattia multiflora is a leguminous tree present only in Mexico and Guatemala. There is no record about its symbiotic or pathogenic microbes. In this study, we found that numerous bacteria with 10(4)-10(6) individuals per gram of fresh epidermis were distributed in the tissue of this plant. All the bacteria isolated from the Conzattia epidermis were Gram-negative, facultative anaerobic rods and formed yellow or colorless colonies. They were identified as endophytes by inoculation tests. Some of the bacteria could significantly promote the growth of Conzattia seedlings. Nine different groups were defined by PCR-based RFLP, which were classified as Pantoea, Erwinia, Salmonella, Enterobacter, Citrobacter and Klebsiella by the phylogenetic analysis of 16S rRNA genes. The existence of plant-borne lineages of Salmonella indicates that the unexplored plants may harbor some unknown microbes.

  2. Isolation of bacteria with antibiotic resistance from household cockroaches (Periplaneta americana and Blattella germanica).

    PubMed

    Pai, Hsiu-Hua; Chen, Wei-Chen; Peng, Chien-Fang

    2005-03-01

    Cockroaches may harbor and disseminate microorganisms to the environment. In this study, Periplaneta americana and Blattella germanica were collected from 40 households in Kaohsiung City and Kaohsiung County, Taiwan. Cockroach infestation was found in 50% of the studied households and 226 cockroaches (123 P. americana and 103 B. germanica) collected by trapping. P. americana was more often found in the kitchen (70.7%) whereas B. germanica in the storage room (51.5%) and kitchen (36.9%). There was no significant difference between the percentages of P. americana (99.9%) and B. germanica (98.0%) carrying bacteria. A total of 25 species of bacteria was isolated from P. americana and only 21 from B. germanica. Antibiotic resistance was found in Staphylococcus aureus, Enterococcus species, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Serratia marcescens, and Proteus species isolated from the cockroaches. These findings suggest a potential role of cockroaches in the transmission of pathogenic bacteria with antibiotic resistance in households.

  3. Surveillance of Carbapenem-Resistant Klebsiella pneumoniae: Tracking Molecular Epidemiology and Outcomes through a Regional Network

    PubMed Central

    Perez, Federico; Rudin, Susan D.; Cober, Eric; Hanrahan, Jennifer; Ziegler, Julie; Webber, Raymond; Fox, Jacqueline; Mason, Pamela; Richter, Sandra S.; Cline, Marianne; Hall, Geraldine S.; Kaye, Keith S.; Jacobs, Michael R.; Kalayjian, Robert C.; Salata, Robert A.; Segre, Julia A.; Conlan, Sean; Evans, Scott; Fowler, Vance G.

    2014-01-01

    Carbapenem resistance in Gram-negative bacteria is on the rise in the United States. A regional network was established to study microbiological and genetic determinants of clinical outcomes in hospitalized patients with carbapenem-resistant (CR) Klebsiella pneumoniae in a prospective, multicenter, observational study. To this end, predefined clinical characteristics and outcomes were recorded and K. pneumoniae isolates were analyzed for strain typing and resistance mechanism determination. In a 14-month period, 251 patients were included. While most of the patients were admitted from long-term care settings, 28% of them were admitted from home. Hospitalizations were prolonged and complicated. Nonsusceptibility to colistin and tigecycline occurred in isolates from 7 and 45% of the patients, respectively. Most of the CR K. pneumoniae isolates belonged to repetitive extragenic palindromic PCR (rep-PCR) types A and B (both sequence type 258) and carried either blaKPC-2 (48%) or blaKPC-3 (51%). One isolate tested positive for blaNDM-1, a sentinel discovery in this region. Important differences between strain types were noted; rep-PCR type B strains were associated with blaKPC-3 (odds ratio [OR], 294; 95% confidence interval [CI], 58 to 2,552; P < 0.001), gentamicin nonsusceptibility (OR, 24; 95% CI, 8.39 to 79.38; P < 0.001), amikacin susceptibility (OR, 11.0; 95% CI, 3.21 to 42.42; P < 0.001), tigecycline nonsusceptibility (OR, 5.34; 95% CI, 1.30 to 36.41; P = 0.018), a shorter length of stay (OR, 0.98; 95% CI, 0.95 to 1.00; P = 0.043), and admission from a skilled-nursing facility (OR, 3.09; 95% CI, 1.26 to 8.08; P = 0.013). Our analysis shows that (i) CR K. pneumoniae is seen primarily in the elderly long-term care population and that (ii) regional monitoring of CR K. pneumoniae reveals insights into molecular characteristics. This work highlights the crucial role of ongoing surveillance of carbapenem resistance determinants. PMID:24798270

  4. Surveillance of carbapenem-resistant Klebsiella pneumoniae: tracking molecular epidemiology and outcomes through a regional network.

    PubMed

    van Duin, David; Perez, Federico; Rudin, Susan D; Cober, Eric; Hanrahan, Jennifer; Ziegler, Julie; Webber, Raymond; Fox, Jacqueline; Mason, Pamela; Richter, Sandra S; Cline, Marianne; Hall, Geraldine S; Kaye, Keith S; Jacobs, Michael R; Kalayjian, Robert C; Salata, Robert A; Segre, Julia A; Conlan, Sean; Evans, Scott; Fowler, Vance G; Bonomo, Robert A

    2014-07-01

    Carbapenem resistance in Gram-negative bacteria is on the rise in the United States. A regional network was established to study microbiological and genetic determinants of clinical outcomes in hospitalized patients with carbapenem-resistant (CR) Klebsiella pneumoniae in a prospective, multicenter, observational study. To this end, predefined clinical characteristics and outcomes were recorded and K. pneumoniae isolates were analyzed for strain typing and resistance mechanism determination. In a 14-month period, 251 patients were included. While most of the patients were admitted from long-term care settings, 28% of them were admitted from home. Hospitalizations were prolonged and complicated. Nonsusceptibility to colistin and tigecycline occurred in isolates from 7 and 45% of the patients, respectively. Most of the CR K. pneumoniae isolates belonged to repetitive extragenic palindromic PCR (rep-PCR) types A and B (both sequence type 258) and carried either blaKPC-2 (48%) or blaKPC-3 (51%). One isolate tested positive for blaNDM-1, a sentinel discovery in this region. Important differences between strain types were noted; rep-PCR type B strains were associated with blaKPC-3 (odds ratio [OR], 294; 95% confidence interval [CI], 58 to 2,552; P < 0.001), gentamicin nonsusceptibility (OR, 24; 95% CI, 8.39 to 79.38; P < 0.001), amikacin susceptibility (OR, 11.0; 95% CI, 3.21 to 42.42; P < 0.001), tigecycline nonsusceptibility (OR, 5.34; 95% CI, 1.30 to 36.41; P = 0.018), a shorter length of stay (OR, 0.98; 95% CI, 0.95 to 1.00; P = 0.043), and admission from a skilled-nursing facility (OR, 3.09; 95% CI, 1.26 to 8.08; P = 0.013). Our analysis shows that (i) CR K. pneumoniae is seen primarily in the elderly long-term care population and that (ii) regional monitoring of CR K. pneumoniae reveals insights into molecular characteristics. This work highlights the crucial role of ongoing surveillance of carbapenem resistance determinants.

  5. Growth of bacteria in enteral feeding solutions.

    PubMed

    Anderton, A

    1985-08-01

    Solutions of Clinifeed ISO, Triosorbon, Vivonex Standard (full- and half-strength) and Vivonex HN were experimentally contaminated with two strains each of Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella aerogenes, Escherichia coli and Enterobacter cloacae at concentrations of 10(2)-10(3) organisms/ml. Samples were incubated at 4, 25 or 37 degrees C and viable counts were made at 0, 4, 8 and 24 h. No increase in numbers of any of the organisms was observed in any of the feeds during 24 h at 4 degrees C. All organisms multiplied rapidly in Clinifeed ISO and in Triosorbon at 25 and 37 degrees C. There was less rapid growth in half-strength Vivonex Standard at 25 degrees C, although at 37 degrees C all strains multiplied rapidly except for the two S. aureus strains, the growth of which was inhibited in half-strength Vivonex Standard at both 25 and 37 degrees C. In full-strength Vivonex Standard at 25 degrees C, only P. aeruginosa showed any increase in numbers during 24 h, whereas P. aeruginosa, K. aerogenes and E. cloacae all multiplied at 37 degrees C. None of the test organisms multiplied in full strength Vivonex HN at any of the temperatures studied. The results of the study show that bacteria survive and may multiply even in feeds with low pH and high osmolarity, and emphasise the importance of strict hygiene during the preparation and handling of all enteral feeds.

  6. [Study of Rapid Species Identification of Bacteria in Water].

    PubMed

    Wang, Jiu-yue; Zhao, Nan-jing; Duan, Jing-bo; Fang, Li; Meng, De-shuo; Yang, Rui-fang; Xiao, Xue; Liu, Jian-guo; Liu, Wen-qing

    2015-09-01

    Multi-wavelength ultraviolet visible (UV-Vis) transmission spectra of bacteria combined the forward scattering and absorption properties of microbes, contains substantial information on size, shape, and the other chemical, physiological character of bacterial cells, has the bacterial species specificity, which can be applied to rapid species identification of bacterial microbes. Four different kinds of bacteria including Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Klebsiella pneumonia which were commonly existed in water were researched in this paper. Their multi-wavelength UV-Vis transmission spectra were measured and analyzed. The rapid identification method and model of bacteria were built which were based on support vector machine (SVM) and multi-wavelength UV-Vis transmission spectra of the bacteria. Using the internal cross validation based on grid search method of the training set for obtaining the best penalty factor C and the kernel parameter g, which the model needed. Established the bacteria fast identification model according to the optimal parameters and one-against-one classification method included in LibSVM. Using different experimental bacteria strains of transmission spectra as a test set of classification accuracy verification of the model, the analysis results showed that the bacterial rapid identification model built in this paper can identification the four kinds bacterial which chosen in this paper as the accuracy was 100%, and the model also can identified different subspecies of E. coli test set as the accuracy was 100%, proved the model had a good stability in identification bacterial species. In this paper, the research results of this study not only can provide a method for rapid identification and early warning of bacterial microbial in drinking water sources, but also can be used as the microbes identified in biomedical a simple, rapid and accurate means.

  7. Identification and characterization of the fis operon in enteric bacteria.

    PubMed

    Beach, M B; Osuna, R

    1998-11-01

    The small DNA binding protein Fis is involved in several different biological processes in Escherichia coli. It has been shown to stimulate DNA inversion reactions mediated by the Hin family of recombinases, stimulate integration and excision of phage lambda genome, regulate the transcription of several different genes including those of stable RNA operons, and regulate the initiation of DNA replication at oriC. fis has also been isolated from Salmonella typhimurium, and the genomic sequence of Haemophilus influenzae reveals its presence in this bacteria. This work extends the characterization of fis to other organisms. Very similar fis operon structures were identified in the enteric bacteria Klebsiella pneumoniae, Serratia marcescens, Erwinia carotovora, and Proteus vulgaris but not in several nonenteric bacteria. We found that the deduced amino acid sequences for Fis are 100% identical in K. pneumoniae, S. marcescens, E. coli, and S. typhimurium and 96 to 98% identical when E. carotovora and P. vulgaris Fis are considered. The deduced amino acid sequence for H. influenzae Fis is about 80% identical and 90% similar to Fis in enteric bacteria. However, in spite of these similarities, the E. carotovora, P. vulgaris, and H. influenzae Fis proteins are not functionally identical. An open reading frame (ORF1) preceding fis in E. coli is also found in all these bacteria, and their deduced amino acid sequences are also very similar. The sequence preceding ORF1 in the enteric bacteria showed a very strong similarity to the E. coli fis P region from -53 to +27 and the region around -116 containing an ihf binding site. Both beta-galactosidase assays and primer extension assays showed that these regions function as promoters in vivo and are subject to growth phase-dependent regulation. However, their promoter strengths vary, as do their responses to Fis autoregulation and integration host factor stimulation.

  8. Genomic Characterization of Two KPC-Producing Klebsiella Isolates Collected in 1997 in New York City.

    PubMed

    Eilertson, Brandon; Chen, Liang; Chavda, Kalyan D; Kreiswirth, Barry N

    2017-04-01

    Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae have now become a global public health threat. However, the origin of this pandemic and the characterization of pre-2003 blaKPC-harboring plasmids remain unknown. Here we used next-generation sequencing to characterize two KPC-2-producing K. pneumoniae and Kmichiganensis isolates collected from a New York City hospital in 1997. Although identified in two different Klebsiella species, the blaKPC-2 gene was harbored by Tn4401b transposons on two highly similar IncN plasmids.

  9. Understanding the patterns of antibiotic susceptibility of bacteria causing urinary tract infection in West Bengal, India

    PubMed Central

    Saha, Sunayana; Nayak, Sridhara; Bhattacharyya, Indrani; Saha, Suman; Mandal, Amit K.; Chakraborty, Subhanil; Bhattacharyya, Rabindranath; Chakraborty, Ranadhir; Franco, Octavio L.; Mandal, Santi M.; Basak, Amit

    2014-01-01

    Urinary tract infection (UTI) is one of the most common infectious diseases at the community level. In order to assess the adequacy of empirical therapy, the susceptibility of antibiotics and resistance pattern of bacteria responsible for UTI in West Bengal, India, were evaluated throughout the period of 2008–2013. The infection reports belonging to all age groups and both sexes were considered. Escherichia coli was the most abundant uropathogen with a prevalence rate of 67.1%, followed by Klebsiella spp. (22%) and Pseudomonas spp. (6%). Penicillin was least effective against UTI-causing E. coli and maximum susceptibility was recorded for the drugs belonging to fourth generation cephalosporins. Other abundant uropathogens, Klebsiella spp., were maximally resistant to broad-spectrum penicillin, followed by aminoglycosides and third generation cephalosporin. The antibiotic resistance pattern of two principal UTI pathogens, E. coli and Klebsiella spp. in West Bengal, appears in general to be similar to that found in other parts of the Globe. Higher than 50% resistance were observed for broad-spectrum penicillin. Fourth generation cephalosporin and macrolides seems to be the choice of drug in treating UTIs in Eastern India. Furthermore, improved maintenance of infection incident logs is needed in Eastern Indian hospitals in order to facilitate regular surveillance of the occurrence of antibiotic resistance patterns, since such levels continue to change. PMID:25278932

  10. Understanding the patterns of antibiotic susceptibility of bacteria causing urinary tract infection in West Bengal, India.

    PubMed

    Saha, Sunayana; Nayak, Sridhara; Bhattacharyya, Indrani; Saha, Suman; Mandal, Amit K; Chakraborty, Subhanil; Bhattacharyya, Rabindranath; Chakraborty, Ranadhir; Franco, Octavio L; Mandal, Santi M; Basak, Amit

    2014-01-01

    Urinary tract infection (UTI) is one of the most common infectious diseases at the community level. In order to assess the adequacy of empirical therapy, the susceptibility of antibiotics and resistance pattern of bacteria responsible for UTI in West Bengal, India, were evaluated throughout the period of 2008-2013. The infection reports belonging to all age groups and both sexes were considered. Escherichia coli was the most abundant uropathogen with a prevalence rate of 67.1%, followed by Klebsiella spp. (22%) and Pseudomonas spp. (6%). Penicillin was least effective against UTI-causing E. coli and maximum susceptibility was recorded for the drugs belonging to fourth generation cephalosporins. Other abundant uropathogens, Klebsiella spp., were maximally resistant to broad-spectrum penicillin, followed by aminoglycosides and third generation cephalosporin. The antibiotic resistance pattern of two principal UTI pathogens, E. coli and Klebsiella spp. in West Bengal, appears in general to be similar to that found in other parts of the Globe. Higher than 50% resistance were observed for broad-spectrum penicillin. Fourth generation cephalosporin and macrolides seems to be the choice of drug in treating UTIs in Eastern India. Furthermore, improved maintenance of infection incident logs is needed in Eastern Indian hospitals in order to facilitate regular surveillance of the occurrence of antibiotic resistance patterns, since such levels continue to change.

  11. Chromosomal Integration of the Klebsiella pneumoniae Carbapenemase Gene, blaKPC, in Klebsiella Species Is Elusive but Not Rare.

    PubMed

    Mathers, Amy J; Stoesser, Nicole; Chai, Weidong; Carroll, Joanne; Barry, Katie; Cherunvanky, Anita; Sebra, Robert; Kasarskis, Andrew; Peto, Tim E; Walker, A Sarah; Sifri, Costi D; Crook, Derrick W; Sheppard, Anna E

    2017-03-01

    Carbapenemase genes in Enterobacteriaceae are mostly described as being plasmid associated. However, the genetic context of carbapenemase genes is not always confirmed in epidemiological surveys, and the frequency of their chromosomal integration therefore is unknown. A previously sequenced collection of blaKPC-positive Enterobacteriaceae from a single U.S. institution (2007 to 2012; n = 281 isolates from 182 patients) was analyzed to identify chromosomal insertions of Tn4401, the transposon most frequently harboring blaKPC Using a combination of short- and long-read sequencing, we confirmed five independent chromosomal integration events from 6/182 (3%) patients, corresponding to 15/281 (5%) isolates. Three patients had isolates identified by perirectal screening, and three had infections which were all successfully treated. When a single copy of blaKPC was in the chromosome, one or both of the phenotypic carbapenemase tests were negative. All chromosomally integrated blaKPC genes were from Klebsiella spp., predominantly K. pneumoniae clonal group 258 (CG258), even though these represented only a small proportion of the isolates. Integration occurred via IS15-ΔI-mediated transposition of a larger, composite region encompassing Tn4401 at one locus of chromosomal integration, seen in the same strain (K. pneumoniae ST340) in two patients. In summary, we identified five independent chromosomal integrations of blaKPC in a large outbreak, demonstrating that this is not a rare event. blaKPC was more frequently integrated into the chromosome of epidemic CG258 K. pneumoniae lineages (ST11, ST258, and ST340) and was more difficult to detect by routine phenotypic methods in this context. The presence of chromosomally integrated blaKPC within successful, globally disseminated K. pneumoniae strains therefore is likely underestimated.

  12. Chromosomal Integration of the Klebsiella pneumoniae Carbapenemase Gene, blaKPC, in Klebsiella Species Is Elusive but Not Rare

    PubMed Central

    Chai, Weidong; Carroll, Joanne; Barry, Katie; Cherunvanky, Anita; Sebra, Robert; Kasarskis, Andrew; Peto, Tim E.; Walker, A. Sarah; Sifri, Costi D.; Crook, Derrick W.; Sheppard, Anna E.

    2016-01-01

    ABSTRACT Carbapenemase genes in Enterobacteriaceae are mostly described as being plasmid associated. However, the genetic context of carbapenemase genes is not always confirmed in epidemiological surveys, and the frequency of their chromosomal integration therefore is unknown. A previously sequenced collection of blaKPC-positive Enterobacteriaceae from a single U.S. institution (2007 to 2012; n = 281 isolates from 182 patients) was analyzed to identify chromosomal insertions of Tn4401, the transposon most frequently harboring blaKPC. Using a combination of short- and long-read sequencing, we confirmed five independent chromosomal integration events from 6/182 (3%) patients, corresponding to 15/281 (5%) isolates. Three patients had isolates identified by perirectal screening, and three had infections which were all successfully treated. When a single copy of blaKPC was in the chromosome, one or both of the phenotypic carbapenemase tests were negative. All chromosomally integrated blaKPC genes were from Klebsiella spp., predominantly K. pneumoniae clonal group 258 (CG258), even though these represented only a small proportion of the isolates. Integration occurred via IS15-ΔI-mediated transposition of a larger, composite region encompassing Tn4401 at one locus of chromosomal integration, seen in the same strain (K. pneumoniae ST340) in two patients. In summary, we identified five independent chromosomal integrations of blaKPC in a large outbreak, demonstrating that this is not a rare event. blaKPC was more frequently integrated into the chromosome of epidemic CG258 K. pneumoniae lineages (ST11, ST258, and ST340) and was more difficult to detect by routine phenotypic methods in this context. The presence of chromosomally integrated blaKPC within successful, globally disseminated K. pneumoniae strains therefore is likely underestimated. PMID:28031204

  13. Polysaccharide-producing bacteria isolated from paper machine slime deposits.

    PubMed

    Rättö, M; Suihko, M-L; Siika-aho, M

    2005-03-01

    Development of novel enzymatic methods for slime deposit control in paper mills requires knowledge of polysaccharide-producing organisms and the polysaccharide structures present in deposits. In this work, 27 polysaccharide-producing bacteria were isolated from slime samples collected from different parts of a paper machine. Most of the isolates produced polysaccharides in liquid culture and nine of them were selected for production of polysaccharides for characterisation. The selected isolates belonged to seven different genera: Bacillus, Brevundimonas, Cytophaga, Enterobacter, Klebsiella, Paenibacillus and Starkeya. Using ribotyping, partial 16S rDNA sequencing, physiological tests and fatty acid analysis, four of the nine isolates: Bacillus cereus, Brevundimonas vesicularis, K. pneumoniae and P. stellifer were identified to the species level. Production of polysaccharides by the selected isolates varied between 0.07 and 1.20 g L(-1), the highest amount being produced by B. vesicularis. The polysaccharides were heteropolysaccharides with varying proportions of galactose, glucose mannose, rhamnose fucose and uronic acids.

  14. The role of surveillance systems in confronting the global crisis of antibiotic-resistant bacteria

    PubMed Central

    Perez, Federico; Villegas, Maria Virginia

    2015-01-01

    Purpose of Review It is widely accepted that infection control, advanced diagnostics, and novel therapeutics are crucial to mitigate the impact of antibiotic-resistant bacteria. The role of global, national and regional surveillance systems as part of the response to the challenge posed by antibiotic resistance is not sufficiently highlighted. We provide an overview of contemporary surveillance programs, with emphasis on Gram-negative bacteria. Recent Findings The World Health Organization and public health agencies in Europe and the United States recently published comprehensive surveillance reports. These highlight the emergence and dissemination of carbapenem-resistant Enterobacteriaceae (CRE) and other multidrug resistant Gram-negative bacteria. In Israel, public health action to control CRE, especially Klebsiella pneumoniae carbapenemase (KPC) producing-Klebsiella pneumoniae, has advanced together with a better understanding of its epidemiology. Surveillance models adapted to the requirements and capacities of each country are in development. Summary Robust surveillance systems are essential to combat antibiotic resistance, and need to emphasize a “One Health” approach. Refinements in surveillance will come from advances in bioinformatics and genomics that permit the integration of global and local information about antibiotic consumption in humans and animals, molecular mechanisms of resistance, and bacterial genotyping. PMID:26098505

  15. Survival of freeze-dried bacteria.

    PubMed

    Miyamoto-Shinohara, Yukie; Sukenobe, Junji; Imaizumi, Takashi; Nakahara, Toro

    2008-02-01

    The aim of this study was to investigate the survival of freeze-dried bacterial species stored at the International Patent Organism Depository (IPOD) and to elucidate the characteristics affecting survival. Bacterial strains were freeze-dried, sealed in ampoules under a vacuum (<1 Pa), and stored in the dark at 5 degrees C. The survival of a variety of species following storage for up to 20 years was analyzed. The survival of freeze-dried species was analyzed in terms of two stages, freeze-drying and storing. Nonmotile genera showed relatively high survival after freeze-drying. Motile genera with peritrichous flagella showed low survival rates after freeze-drying. Vibrio and Aeromonas, which produce numerous flagella, showed very low survival rates. In Lactobacillus, non-trehalose-fermenting species showed better survival rates after freeze-drying than did fermenting species, and those species with teichoic acid in the cell wall showed lower survival rates during storage than species with teichoic acid in the cell membrane. Human pathogenic species of Corynebacterium, Bacillus, Streptococcus, and Klebsiella showed lower survival rates during storage than nonpathogenic species within the same genus. Among Pseudomonas species, P. chlororaphis, the only species tested that forms levan from sucrose, showed the lowest survival rate during storage in the genus. Survival rates of Gram-negative species during storage tended to be lower than those of Gram-positive species, though Chryseobacterium meningosepticum had stable survival during storage. The conclusion is that smooth cell surfaces (i.e., no flagella) and lack of trehalose outside the cytoplasm improved survival rates after freeze-drying. Because desiccation is important for survival during storage, the presence of extracellular polysaccharides or teichoic acids is disadvantageous for long-term survival. The lower survival rates of freeze-dried Gram-negative bacteria compared with those of Gram-positive bacteria

  16. Genomics of Probiotic Bacteria

    NASA Astrophysics Data System (ADS)

    O'Flaherty, Sarah; Goh, Yong Jun; Klaenhammer, Todd R.

    Probiotic bacteria from the Lactobacillus and Bifidobacterium species belong to the Firmicutes and the Actinobacteria phylum, respectively. Lactobacilli are members of the lactic acid bacteria (LAB) group, a broadly defined family of microorganisms that ferment various hexoses into primarily lactic acid. Lactobacilli are typically low G + C gram-positive species which are phylogenetically diverse, with over 100 species documented to date. Bifidobacteria are heterofermentative, high G + C content bacteria with about 30 species of bifidobacteria described to date.

  17. Salmonellae and other enteropathogenic bacteria in the intestines of wall geckos in Nigeria.

    PubMed

    Gugnani, H C; Oguike, J U; Sakazaki, R

    1986-01-01

    The aerobic bacterial flora of the intestine of 150 wall geckos (Hemidactylus brookei) was investigated. A variety of bacteria was recovered including 35 isolates of Salmonella and several other species of Enterobacteriaceae, viz. Shigella sonnei - 2, Edwardsiella tarda - 4, Enterobacter spp - 8, Citrobacter freudii - 3, Serratia marcescens - 3, Proteus spp - 35, Klebsiella pneumoniae - 13, and Escherichia coli - 17, isolates. Eight Salmonella serotypes were identified, the predominant ones being S. hvittingfoss and S. typhimurium. The significance of these findings for the spread of human enteropathogens is discussed.

  18. Chlorine resistance patterns of bacteria from two drinking water distribution systems.

    PubMed Central

    Ridgway, H F; Olson, B H

    1982-01-01

    The relative chlorine sensitivities of bacteria isolated from chlorinated and unchlorinated drinking water distribution systems were compared by two independent methods. One method measured the toxic effect of free chlorine on bacteria, whereas the other measured the effect of combined chlorine. Bacteria from the chlorinated system were more resistant to both the combined and free forms of chlorine than those from the unchlorinated system, suggesting that there may be selection for more chlorine-tolerant microorganisms in chlorinated waters. Bacteria retained on the surfaces of 2.0-microns Nuclepore membrane filters were significantly more resistant to free chlorine compared to the total microbial population recovered on 0.2-micron membrane filters, presumably because aggregated cells or bacteria attached to suspended particulate matter exhibit more resistance than unassociated microorganisms. In accordance with this hypothesis, scanning electron microscopy of suspended particulate matter from the water samples revealed the presence of attached bacteria. The most resistant microorganisms were able to survive a 2-min exposure to 10 mg of free chlorine per liter. These included gram-positive spore-forming bacilli, actinomycetes, and some micrococci. The most sensitive bacteria were readily killed by chlorine concentrations of 1.0 mg liter-1 or less, and included most gram-positive micrococci, Corynebacterium/Arthrobacter, Klebsiella, Pseudomonas/Alcaligenes, Flavobacterium/Moraxella, and Acinetobacter. Images PMID:7149722

  19. Factors influencing inactivation of Klebsiella pneumoniae by chlorine and chloramine.

    PubMed

    Goel, Sudha; Bouwer, Edward J

    2004-01-01

    Inactivation of Klebsiella pneumoniae cultures by chlorine and chloramine was evaluated under different growth conditions by varying nutrient media dilution, concentrations of essential inorganic nutrients (FeCl3, MgSO4, phosphate, and ammonium salts), and temperature. All inactivation assays were performed at room temperature (22-23 degrees C) and near neutral pH (7.2-7.5). C*T(99.9) values for chlorine increased >20-fold and for chloramine increased 2.6-fold when cells were grown in 100-fold diluted nutrient broth (2NB) solutions (final TOC of 35-40 mg/L). Background levels of Mg: 6.75 x 10(-2) mM and Fe: 3.58 x 10(-5) mM or high levels of FeCl3 (0.01 mM) and MgSO4 (1 mM) during growth resulted in the highest resistances to chlorine with C*T(99.9) values of 13.06 (+/-0.91) and 13.78 (+/-1.97) mg-min/L, respectively. Addition of low levels of FeCl3 (0.001 mM) and MgSO4 (0.1 mM) to K. pneumoniae cultures during growth resulted in the lowest bacterial resistances to inactivation; C*T(99.9) values ranged from 0.28 (+/-0.06) to 1.88 (+/-0.53)mg-min/L in these cultures. Increase in growth temperature from 22.5 degrees C to 35 degrees C for unamended 2NB cultures resulted in a 42-fold decrease in C*T(99.9) values for chlorine. A similar change in temperature resulted in no significant change in C*T(99.9) values for chloramine. These results indicate that inactivation of K. pneumoniae cultures by chlorine was highly sensitive to changes in growth conditions unlike inactivation by chloramine.

  20. Molecular Epidemiology of Colonizing and Infecting Isolates of Klebsiella pneumoniae

    PubMed Central

    Martin, Rebekah M.; Cao, Jie; Brisse, Sylvain; Passet, Virginie; Wu, Weisheng; Zhao, Lili; Malani, Preeti N.; Rao, Krishna

    2016-01-01

    ABSTRACT Klebsiella pneumoniae is among the most common causes of hospital-acquired infections and has emerged as an urgent threat to public health due to carbapenem antimicrobial resistance. K. pneumoniae commonly colonizes hospitalized patients and causes extraintestinal infections such as urinary tract infection, bloodstream infection (septicemia), and pneumonia. If colonization is an intermediate step before infection, then detection and characterization of colonizing isolates could enable strategies to prevent or empirically treat K. pneumoniae infections in hospitalized patients. However, the strength of the association between colonization and infection is unclear. To test the hypothesis that hospitalized patients become infected with their colonizing strain, 1,765 patients were screened for rectal colonization with K. pneumoniae, and extraintestinal isolates from these same patients were collected over a 3-month period in a cohort study design. The overall colonization prevalence was 23.0%. After adjustment for other patient factors, colonization was significantly associated with subsequent infection: 21 of 406 (5.2%) colonized patients later had extraintestinal infection, compared to 18 of 1,359 (1.3%) noncolonized patients (adjusted odds ratio [OR], 4.01; 95% confidence interval, 2.08 to 7.73; P < 0.001). Despite a high diversity of colonizing isolates, 7/7 respiratory, 4/4 urinary, and 2/5 bloodstream isolates from colonized patients matched the patient corresponding rectal swab isolates, based on wzi capsular typing, multilocus sequence typing (MLST), and whole-genome sequence analysis. These results suggest that K. pneumoniae colonization is directly associated with progression to extraintestinal infection. IMPORTANCE K. pneumoniae commonly infects hospitalized patients, and these infections are increasingly resistant to carbapenems, the antibiotics of last resort for life-threatening bacterial infections. To prevent and treat these infections, we

  1. Immunogenic properties of Klebsiella pneumoniae type 2 capsular polysaccharide.

    PubMed Central

    Robert, A; Jouin, H; Fournier, J M

    1986-01-01

    The immunoprotective activity of Klebsiella pneumoniae K2 cell surface preparations and purified capsular polysaccharide was tested in mice. The 50% protective dose (PD50), expressed as capsular polysaccharide content, was 2 ng for cell surface preparations and 50 ng for purified capsular polysaccharide. Both preparations lost their immunoprotective activity after alkali treatment. Immune sera were raised in rabbits immunized with cell surface preparations. The precipitating and hemagglutinating capacity of these antisera was tested against either purified capsular polysaccharide or alkali-treated capsular polysaccharide. No difference was observed between the reactivity of the antisera against each antigen. The protective activity of these sera was tested on mice in passive transfer experiments, before and after absorption with either purified capsular polysaccharide or alkali-treated capsular polysaccharide. The sera lost their protective activity after absorption with purified capsular polysaccharide and after absorption with alkali-treated capsular polysaccharide. These experiments show that the difference in immunoprotective activity of cell surface preparations, purified capsular polysaccharide, and alkali-treated capsular polysaccharide is not due to a difference in their antigenic determinants. Cell surface preparations and purified capsular polysaccharide were fractionated by gel filtration on Sepharose 4B and by ultracentrifugation on cesium chloride density gradients. Three forms of capsular polysaccharide have been characterized. (i) A form of capsular polysaccharide with a very high protective activity (PD50 = 2 ng) that copurified with protein and lipopolysaccharide and was characterized by a low coefficient of distribution (Kd = 0.20) and a low density (1.5 to 1.6 g/cm3). (ii) A form of capsular polysaccharide with an intermediate protective activity (PD50 = 50 ng), contamined by less than 3% protein and 1% lipopolysaccharide, with a Kd of 0.35, and

  2. Regulation of anaerobic citrate metabolism in Klebsiella pneumoniae.

    PubMed

    Bott, M; Meyer, M; Dimroth, P

    1995-11-01

    Three enzymes are specifically required for uptake and catabolism of citrate by Klebsiella pneumoniae under anaerobic conditions: a Na+ -dependent citrate carrier (CitS), citrate lyase (CitDEF), and the Na+ pump oxaloacetate decarboxylase (OadGAB). The corresponding genes are clustered on the chromosome, with the citCDEFG genes located upstream and divergent to the citS-oadGAB genes. We found that expression of citS from its native promoter in Escherichia coli requires the DNA region downstream of oadB. Nucleotide sequence analysis of this region revealed the presence of two adjacent genes, citA and citB. By sequence similarity, the predicted CitA and CitB proteins were identified as members of the two-component regulatory systems. The sensor kinase CitA contained, in the N-terminal half, two putative transmembrane helices which enclosed a presumably periplasmic domain of about 130 amino acids. The C-terminal half of the response regulator CitB harboured a helix-turn-helix motif typical of DNA-binding proteins. K. pneumoniae citB null mutants were unable to grow anaerobically with citrate as the sole carbon and energy source (Cit- phenotype). When cultivated anaerobically with citrate plus glycerol, all of the citrate-specific fermentation enzymes were synthesized in the wild type, but not in the citB mutants. This showed that citS, oadGAB and citDEF required the CitB protein for expression and therefore are part of a regulon. In the wild type, synthesis of CitS, oxaloacetate decarboxylase and citrate lyase was dependent on the presence of citrate, sodium ions and a low oxygen tension. In a citA null mutant which expressed citB constitutively at high levels, none of these signals was required for the formation of the citrate fermentation enzymes. This result suggested that citrate, Na+, and oxygen exerted their regulatory effects via the CitA/CitB system. In the presence of these signals, the citAB gene products induced their own synthesis. The positive

  3. Osteomyelitis due to multiple carbapenemase-producing Gram-negative bacteria: The first case report of a GES-13-producing Pseudomonas aeruginosa isolate in Canada.

    PubMed

    Sepehri, Shadi; Poliquin, Guillaume; Alfattoh, Nora; Boyd, David; Mulvey, Michael; Denisuik, Andrew; Fanella, Sergio; Karlowsky, James; Walkty, Andrew

    2014-07-01

    A case of osteomyelitis in an infant following a burn injury sustained in Pakistan caused by a GES-13-producing Pseudomonas aeruginosa (the first reported in Canada) and an OXA-48 producing Klebsiella pneumoniae is described. The present case serves to highlight the importance of international travel as a risk factor for infection with carbapenemase-producing bacteria and the challenges in the laboratory detection of these organisms.

  4. Clinical and pulmonary thin-section CT findings in acute Klebsiella pneumoniae pneumonia.

    PubMed

    Okada, Fumito; Ando, Yumiko; Honda, Koichi; Nakayama, Tomoko; Kiyonaga, Maki; Ono, Asami; Tanoue, Shuichi; Maeda, Toru; Mori, Hiromu

    2009-04-01

    The aim of this study was to assess the clinical and pulmonary thin-section CT findings in patients with acute Klebsiella pneumoniae pneumonia. We retrospectively evaluated thin-section CT examinations performed between January 1991 and December 2007 from 962 patients with acute Klebsiella pneumoniae pneumonia. Seven hundred and sixty-four cases with concurrent infectious diseases were excluded. Thus, our study group comprised 198 patients (118 male, 80 female; age range 18-97 years, mean age 61.5). Underlying diseases and clinical findings were assessed. Parenchymal abnormalities were evaluated along with the presence of enlarged lymph nodes and pleural effusion. CT findings in patients with acute Klebsiella pneumoniae pneumonia consisted mainly of ground-glass attenuation (100%), consolidation (91.4%), and intralobular reticular opacity (85.9%), which were found in the periphery (96%) of both sides of the lungs (72.2%) and were often associated with pleural effusion (53%). The underlying conditions in patients with Klebsiella pneumoniae pneumonia were alcoholism or smoking habit.

  5. Role of triggering receptor expressed on myeloid cells-1/3 in Klebsiella-derived pneumosepsis.

    PubMed

    Hommes, Tijmen J; Dessing, Mark C; Veer, Cornelis van 't; Florquin, Sandrine; Colonna, Marco; de Vos, Alex F; van der Poll, Tom

    2015-11-01

    Triggering receptor expressed on myeloid cells (TREM)-1 and -2 can affect Toll-like receptor-mediated activation of immune cells. Klebsiella pneumoniae is a common cause of pneumonia-derived sepsis. Here we studied the role of TREM-1/3 and TREM-2 in the host response during Klebsiella pneumonia. Macrophages lacking either TREM-1/3 or TREM-2 were tested for their responsiveness toward K. pneumoniae and for their capacity to internalize this pathogen in vitro. TREM-1/3- and TREM-2-deficient mice were infected with K. pneumoniae via the airways, and their responses were compared with those in wild-type mice. TREM-1/3-deficient macrophages produced lower cytokine levels upon exposure to K. pneumoniae, whereas TREM-2-deficient macrophages released higher cytokine concentrations. TREM-2-deficient, but not TREM-1/3-deficient, macrophages showed a reduced capacity to phagocytose K. pneumoniae. TREM-1/3-deficient mice showed an impaired host defense during Klebsiella pneumonia, as reflected by worsened survival and increased bacterial growth and dissemination. In contrast, TREM-2 deficiency did not affect disease outcome. Although TREM-1/3 and TREM-2 influence macrophage responsiveness to K. pneumoniae in vitro, only TREM-1/3 contribute to the host response during Klebsiella pneumonia in vivo, serving a protective role.

  6. [Predominance and evolution of BLA(SHV) genes in Tunisian hospital isolates of Klebsiella pneumoniae].

    PubMed

    Ben-Hamouda, T; Ben-Mahrez, K

    2005-01-01

    Extended-spectrum beta-lactamases (ESBLs)produced by clinical strains of Klebsiella pneumoniae were investigated, using isoelectric-focusing and DNA amplification followed by sequencing. A predominance of SHV variants was found. Sequencing identified the genes for the SHV-2a and -12 enzymes, suggesting direct evolution of SHV-12 from SHV-2a.

  7. Neonatal Klebsiella Septicaemia in Ibadan: Implications for Neonatal Care in Developing Countries.

    ERIC Educational Resources Information Center

    Omokhodion, S. I.; And Others

    1993-01-01

    The antecedent events, clinical features, prevalence, and complications of neonatal Klebsiella septicaemia in 73 infants admitted to a special care baby unit in Nigeria are retrospectively reviewed and compared with those of 72 infants who had no risk factors for sepsis admitted to the same unit during the same period. A nosocomial acquisition of…

  8. Draft Genome Sequences of Three Hypervirulent Carbapenem-Resistant Klebsiella pneumoniae Isolates from Bacteremia

    PubMed Central

    Shankar, Chaitra; Nabarro, Laura E. B.; Devanga Ragupathi, Naveen Kumar; Muthuirulandi Sethuvel, Dhiviya Prabaa; Daniel, Jones Lionel Kumar; Doss C, George Priya

    2016-01-01

    Hypervirulent Klebsiella pneumoniae strains have been increasingly reported worldwide, and there is emergence of carbapenem resistance among them. Here, we report the genome sequences of three carbapenem-resistant hypervirulent K. pneumoniae isolates isolated from bacteremic patients at a tertiary-care center in South India. PMID:27932638

  9. Non-clostridial gas gangrene caused by Klebsiella pneumoniae: a case report.

    PubMed

    Li, C M; Chen, P L; Ho, Y R

    2001-01-01

    A 45-y-old man was hospitalized due to pain and swelling of the right leg for 3 d. Bullae developed with gas formation involving multiple compartments of the entire limb 46 h later. Klebsiella pneumoniae was recovered from blood and surgical specimens. The patient died on Day 8 despite amputation and antibiotic therapy.

  10. Complete genome sequence of a Klebsiella pneumoniae strain isolated from a known cotton insect boll vector

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Klebsiella pneumoniae (associated with bacterial pneumonia) was previously isolated from Nezara viridula, a significant vector of cotton boll-rot pathogens. We provide the first annotated genome sequence of the cotton opportunistic strain K. pneumoniae 5-1. This data provides guidance to study the...

  11. Klebsiella pneumoniae Strains Producing Extended-Spectrum β-Lactamases in Spain: Microbiological and Clinical Features▿

    PubMed Central

    de Alegría, C. Ruiz; Rodríguez-Baño, J.; Cano, M. E.; Hernández-Bello, J. R.; Calvo, J.; Román, E.; Díaz, M. A.; Pascual, A.; Martínez-Martínez, L.

    2011-01-01

    Extended-spectrum β-lactamases (ESBL) of the CTX-M, SHV, and TEM families were recognized in 76 (67%), 31 (27%), and 6 (5%) isolates, respectively, among 162 ESBL-producing Klebsiella pneumoniae (ESBL-Kp) strains obtained in a multicenter study in Spain. Predisposing factors for ESBL-Kp acquisition included invasive procedures, mechanical ventilation, and previous antimicrobial use. PMID:21191059

  12. Klebsiella pneumoniae strains producing extended-spectrum beta-lactamases in Spain: microbiological and clinical features.

    PubMed

    Ruiz de Alegría, C; Rodríguez-Baño, J; Cano, M E; Hernández-Bello, J R; Calvo, J; Román, E; Díaz, M A; Pascual, A; Martínez-Martínez, L

    2011-03-01

    Extended-spectrum β-lactamases (ESBL) of the CTX-M, SHV, and TEM families were recognized in 76 (67%), 31 (27%), and 6 (5%) isolates, respectively, among 162 ESBL-producing Klebsiella pneumoniae (ESBL-Kp) strains obtained in a multicenter study in Spain. Predisposing factors for ESBL-Kp acquisition included invasive procedures, mechanical ventilation, and previous antimicrobial use.

  13. Genome Sequence of Klebsiella quasipneumoniae subsp. similipneumoniae MB373, an Effective Bioremediator

    PubMed Central

    Aslam, Fozia; Thomas, Torsten

    2016-01-01

    Klebsiella quasipneumoniae subsp. similipneumoniae MB373 was isolated from effluent of the Hattar Industrial Estate, Haripur, Pakistan. K. quasipneumoniae subsp. similipneumoniae has few cultivated/characterized members so far. Whole-genome sequencing revealed its potential for metal and toxin resistance, which further elucidated various enzymatic processes for the degradation of xenobiotics, illuminating its bioremediation applications. PMID:27688323

  14. High-level resistance to cefotaxime and ceftazidime in Klebsiella pneumoniae isolates from Cleveland, Ohio.

    PubMed Central

    Thomson, K S; Sanders, C C; Washington, J A

    1991-01-01

    Two isolates of Klebsiella pneumoniae possessing both TEM-1 and SHV-2 beta-lactamases were isolated from patients at the Cleveland Clinic in 1988. The beta-lactamases were discriminated and identified by using substrate hydrolysis data and an isoelectric focusing procedure in which the gel was overlaid with beta-lactamase inhibitors. Images PMID:1854155

  15. Draft Genome Sequence of Klebsiella pneumoniae subsp. pneumoniae ATCC 9621

    PubMed Central

    Najdenski, Hristo

    2017-01-01

    ABSTRACT We present here the 5.561-Mbp assembled draft genome sequence of Klebsiella pneumoniae subsp. pneumoniae ATCC 9621, a phosphite- and organophosphonate-assimilating Gammaproteobacterium. The genome harbors 5,179 predicted protein-coding genes. PMID:28336608

  16. Necrotizing fasciitis caused by hypermucoviscous Klebsiella pneumoniae in a Filipino female in North America.

    PubMed

    Ng, Daniel; Frazee, Brad

    2015-01-01

    Necrotizing fasciitis caused by Klebsiella pneumoniae has been described in Southeast Asia, but has only recently begun to emerge in North America. The hypermucoviscous strain of K. pneumoniae is a particularly virulent strain known to cause devastatingly invasive infections, including necrotizing fasciitis. Here we present the first known case of necrotizing fasciitis caused by hypermucoviscous K. pneumoniae in North America.

  17. Immunoproteomic to Analysis the Pathogenicity Factors in Leukopenia Caused by Klebsiella Pneumonia Bacteremia

    PubMed Central

    Liu, Haiyan; Cheng, Zhongle; Song, Wen; Wu, Wenyong; Zhou, Zheng

    2014-01-01

    Incidences of leukopenia caused by bacteremia have increased significantly and it is associated with prolonged hospital stay and increased cost. Immunoproteomic is a promising method to identify pathogenicity factors of different diseases. In the present study, we used immunoproteomic to analysis the pathogenicity factors in leukopenia caused by Klebsiella Pneumonia bacteremia. Approximately 40 protein spots localized in the 4 to 7 pI range were detected on two-dimensional electrophoresis gels, and 6 differentially expressed protein spots between 10 and 170 kDa were identified. Pathogenicity factors including S-adenosylmethionine synthetase, pyruvate dehydrogenase, glutathione synthetase, UDP-galactose-4-epimerase, acetate kinase A and elongation factor tu (EF-Tu). In validation of the pathogenicity factor, we used western blotting to show that Klebsiella pneumonia had higher (EF-Tu) expression when they accompanied by leukopenia rather than leukocytosis. Thus, we report 6 pathogenicity factors of leukopenia caused by Klebsiella pneumonia bacteremia, including 5 housekeeping enzymes and EF-Tu. We suggest EF-Tu could be a potential pathogenicity factor for leukopenia caused by Klebsiella pneumonia. PMID:25330314

  18. Phenotypic and molecular characterization of multidrug resistant Klebsiella pneumoniae isolated from a university teaching hospital, China.

    PubMed

    Du, Jikun; Li, Peipei; Liu, Helu; Lü, Dongyue; Liang, Hong; Dou, Yuhong

    2014-01-01

    The multidrug-resistant rate of Klebsiella pneumoniae has risen rapidly worldwide. To better understand the multidrug resistance situation and molecular characterization of Klebsiella pneumoniae, a total of 153 Klebsiella pneumoniae isolates were collected, and drug susceptibility test was performed to detect its susceptibility patterns to 13 kinds of antibiotics. Phenotypic tests for carbapenemases ESBLs and AmpC enzyme-producing strains were performed to detect the resistance phenotype of the isolates. Then PCR amplification and sequencing analysis were performed for the drug resistance determinants. The results showed that 63 strains harbored bla CTX-M gene, and 14 strains harbored bla DHA gene. Moreover, there were 5 strains carrying bla KPC gene, among which 4 strains carried bla CTX-M, bla DHA and bla KPC genes, and these 4 strains were also resistant to imipenem. Our data indicated that drug-resistant Klebsiella pneumoniae were highly prevalent in the hospital. Thus it is warranted that surveillance of epidemiology of those resistant isolates should be a cause for concern, and appropriate drugs should be chosen.

  19. Liver Abscess Caused by Infection with Community-Acquired Klebsiella quasipneumoniae subsp. quasipneumoniae.

    PubMed

    Breurec, Sebastien; Melot, Benedicte; Hoen, Bruno; Passet, Virginie; Schepers, Kinda; Bastian, Sylvaine; Brisse, Sylvain

    2016-03-01

    We report a case of pyogenic liver abscess caused by community-acquired Klebsiella quasipneumoniae subsp. quasipneumoniae. The infecting isolate had 2 prominent features of hypervirulent K. pneumoniae strains: the capsular polysaccharide synthesis region for K1 serotype and the integrative and conjugative element ICEKp1, which encodes the virulence factors yersiniabactin, salmochelin, and RmpA.

  20. Intestinal Decontamination of Multidrug-resistant Klebsiella pneumoniae After Recurrent Infections in an Immunocompromised Host

    PubMed Central

    Kronman, Matthew P.; Zerr, Danielle M.; Qin, Xuan; Englund, Janet; Cornell, Cathy; Sanders, Jean E.; Myers, Jeffrey; Rayar, Jaipreet; Berry, Jessica E.; Adler, Amanda L.; Weissman, Scott J.

    2014-01-01

    Multidrug-resistant (MDR) Enterobacteriaceae infections are associated with increased morbidity. We describe a 20-year-old hematopoietic cell transplantation recipient with recurrent MDR Klebsiella pneumoniae infection, prolonged intestinal colonization, and subsequent intestinal decontamination. Further study should evaluate stool surveillance, molecular typing, and fecal microbiota transplantation for patients with intestinal MDR Enterobacteriaceae carriage. PMID:25041704

  1. Complete Genome Sequence of KPC-Producing Klebsiella pneumoniae Strain CAV1193

    PubMed Central

    Sebra, Robert; Kasarskis, Andrew; Deikus, Gintaras; Anson, Luke; Walker, A. Sarah; Peto, Tim E.; Crook, Derrick W.

    2016-01-01

    Carbapenem resistance in Klebsiella pneumoniae, frequently conferred by the blaKPC gene, is a major public health threat. We sequenced a blaKPC-containing strain of K. pneumoniae belonging to the emergent lineage ST941, in order to better understand the evolution of blaKPC within this species. PMID:26823590

  2. Complete Genome Sequence of KPC-Producing Klebsiella pneumoniae Strain CAV1193.

    PubMed

    Sheppard, Anna E; Stoesser, Nicole; Sebra, Robert; Kasarskis, Andrew; Deikus, Gintaras; Anson, Luke; Walker, A Sarah; Peto, Tim E; Crook, Derrick W; Mathers, Amy J

    2016-01-28

    Carbapenem resistance in Klebsiella pneumoniae, frequently conferred by the blaKPC gene, is a major public health threat. We sequenced a blaKPC-containing strain of K. pneumoniae belonging to the emergent lineage ST941, in order to better understand the evolution of blaKPC within this species.

  3. Draft Genome Sequence of a Klebsiella pneumoniae Strain (New Sequence Type 2357) Carrying Tn3926

    PubMed Central

    Mi, Zu-huang; Wang, Chun-xin; Zhu, Jian-ming

    2016-01-01

    We present the draft genome sequence of a Klebsiella pneumoniae carbapenemase–producing sequence type 2357 (ST2357) strain, NB60, which contains drug-resistant genes encoding resistance to beta-lactams, fluoroquinolones, aminoglycosides, trimethoprim-sulfamethoxazole, colistin, macrolides, and tetracycline. Strain NB60 was isolated from human blood, making it an important tool for studying K. pneumoniae pathogenesis. PMID:27660779

  4. Phenotypic and Molecular Characterization of Multidrug Resistant Klebsiella pneumoniae Isolated from a University Teaching Hospital, China

    PubMed Central

    Liu, Helu; Lü, Dongyue; Liang, Hong; Dou, Yuhong

    2014-01-01

    The multidrug-resistant rate of Klebsiella pneumoniae has risen rapidly worldwide. To better understand the multidrug resistance situation and molecular characterization of Klebsiella pneumoniae, a total of 153 Klebsiella pneumoniae isolates were collected, and drug susceptibility test was performed to detect its susceptibility patterns to 13 kinds of antibiotics. Phenotypic tests for carbapenemases ESBLs and AmpC enzyme-producing strains were performed to detect the resistance phenotype of the isolates. Then PCR amplification and sequencing analysis were performed for the drug resistance determinants. The results showed that 63 strains harbored blaCTX-M gene, and 14 strains harbored blaDHA gene. Moreover, there were 5 strains carrying blaKPC gene, among which 4 strains carried blaCTX-M, blaDHA and blaKPC genes, and these 4 strains were also resistant to imipenem. Our data indicated that drug-resistant Klebsiella pneumoniae were highly prevalent in the hospital. Thus it is warranted that surveillance of epidemiology of those resistant isolates should be a cause for concern, and appropriate drugs should be chosen. PMID:24740167

  5. Novel VIM metallo-beta-lactamase variant, VIM-24, from a Klebsiella pneumoniae isolate from Colombia.

    PubMed

    Montealegre, Maria Camila; Correa, Adriana; Briceño, David F; Rosas, Natalia C; De La Cadena, Elsa; Ruiz, Sory J; Mojica, Maria F; Camargo, Ruben Dario; Zuluaga, Ivan; Marin, Adriana; Quinn, John P; Villegas, Maria Virginia

    2011-05-01

    We report the emergence of a novel VIM variant (VIM-24) in a Klebsiella pneumoniae isolate in Colombia. The isolate displays MICs for carbapenems below the resistance breakpoints, posing a real challenge for its detection. The blaVIM-24 gene was located within a class 1 integron carried on a large plasmid. Further studies are needed to clarify its epidemiological and clinical impact.

  6. Genome Sequence of OXA-48 Carbapenemase-Producing Klebsiella pneumoniae KpO3210

    PubMed Central

    Wesselink, Jan-Jaap; López-Camacho, Elena; de la Peña, Santiago; Ramos-Ruiz, Ricardo; Ruiz-Carrascoso, Guillermo; Lusa-Bernal, Silvia; Fernández-Soria, Victor M.; Gómez-Gil, Rosa

    2012-01-01

    Klebsiella pneumoniae KpO3210 is a OXA-48 carbapenemase-producing isolate obtained from a blood culture in the context of an outbreak in Hospital Universitario La Paz (Madrid, Spain) in 2010. It belongs to the major clone detected during the outbreak and is resistant to all beta-lactams and to several other antibiotics. PMID:23209233

  7. Prevalence of antimicrobial resistance in Escherichia coli and Klebsiella spp. in rural South India.

    PubMed

    Sekar, Ramalingam; Mythreyee, Manoharan; Srivani, Seetharaman; Amudhan, Murugesan

    2016-06-01

    The emergence and dissemination of antimicrobial resistance (AMR) is an important public health problem as resistant organisms cause difficult-to-treat infections. In this study, the prevalence of AMR in Escherichia coli and Klebsiella spp. in rural South India was examined in order to aid empirical therapy. A cross-sectional prospective study was conducted during the period from January 2012 to December 2014. Routine clinical isolates of E. coli and Klebsiella spp. were tested for antimicrobial susceptibility to β-lactams, aminoglycosides, fluoroquinolones, tetracyclines, colistin and nitrofurantoin by the Kirby-Bauer disk diffusion method and the data were documented and analyzed with one per patient analysis using WHONET software. A total of 2292 non-duplicate clinical isolates were recovered during the study period, including 1338 E. coli and 954 Klebsiella spp. The prevalence of AMR in the total isolates was as follows: amikacin, 17.3%; ertapenem, 14.4%; doripenem, 4.5%; colistin, 13.2%; and tigecycline, 4.1%. The study results indicate a high prevalence of carbapenem resistance in Klebsiella spp. especially from pus and urinary isolates, whilst the prevalence of aztreonam and fluoroquinolone resistance was very high in E. coli.

  8. Phenotypic and genotypic characterization of Klebsiella pneumonia recovered from nonhuman primates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Klebsiella pneumoniae is a zoonotic, Gram-negative member of the family Enterobacteriaceae and is the causative agent of nosocomial septicemic, pneumonic, and urinary tract infections. Recently, pathogenic strains of K. pneumoniae sharing a hypermucoviscosity (HMV) phenotype have been attributed to ...

  9. Bleach vs. Bacteria

    MedlinePlus

    ... Inside Life Science > Bleach vs. Bacteria Inside Life Science View All Articles | Inside Life Science Home Page Bleach vs. Bacteria By Sharon Reynolds ... For Proteins, Form Shapes Function This Inside Life Science article also appears on LiveScience . Learn about related ...

  10. Some bacteria are beneficial!

    USGS Publications Warehouse

    McMahon, Peter B.

    1995-01-01

    Most people would agree that bacteria usually spell trouble where the quality of drinking water is con cerned. However, recent studies conducted by the U.S. Geological Survey (USGS) under the National Water-Quality Assessment (NAWQA) program have shown that some bacteria can improve the quality of water.

  11. Bacteria turn tiny gears

    SciTech Connect

    2009-01-01

    Swarms of bacteria turn two 380-micron long gears, opening the possibility of building hybrid biological machines at the microscopic scale. Read more at Wired: http://www.wired.com/wiredscience/2009/12/bacterial-micro-machine/#more-15684 or Scientific American: http://www.scientificamerican.com/article.cfm?id=brownian-motion-bacteria

  12. [Epidemiological features of multidrug resistant bacteria isolated from urine samples at the Mohammed V Military Teaching Hospital in Rabat, Morocco].

    PubMed

    Zohoun, A; Ngoh, E; Bajjou, T; Sekhsokh, Y; Elhamzaoui, S

    2010-08-01

    Hospital-acquired multidrug resistant bacteria infections are a serious public health issue causing increased morbidity, mortality and care cost. These risks underscore the need for health care institutions to maintain active panels to monitor, prevent, and manage hospital-acquired infections. The purpose of this study was to assess the epidemiology of urinary tract infection involving multidrug resistant bacteria at the Microbiology Laboratory of the Mohammed-V Military Teaching Hospital in Rabat. Study was carried out retrospectively on bacteria isolated from 10,243 urinary samples collected from January 1 to December 31, 2008. A total of 1,439 non-redundant bacteria (14.1%) meeting the criteria of urinary infection were identified. One hundred and three of the 1,439 bacteria isolated (7%) were multidrug resistant. Multidrug-resistant bacteria were more common in in-patients (63.1%). Mean patient age was 53.8 +/- 18.2 and the M/F sex ratio was 2.2. The most common multi-drug resistant bacteria were Enterobacteria producing extended spectrum bêta-lactamase (54.4% including 40.8% of Klebsiella pneumonia) and non-fermenting bacteria (45.6% including 26.2% of Pseudomonas aeruginosa. and 19.4% of Acinetobacter baumannii. These bacteria were resistant to the most commonly used antibiotics but remained highly sensitive to colistin, imipenem and amikacin.

  13. Klebsiella pneumonia, a Microorganism that Approves the Non-linear Responses to Antibiotics and Window Theory after Exposure to Wi-Fi 2.4 GHz Electromagnetic Radiofrequency Radiation

    PubMed Central

    Taheri, M.; Mortazavi, S. M. J.; Moradi, M.; Mansouri, Sh.; Nouri, F.; Mortazavi, S. A. R.; Bahmanzadegan, F.

    2015-01-01

    Background Drug resistance is widely believed to be an increasingly serious threat to global public health. We have previously reported that short term exposure of microorganisms to diagnostic ultrasound waves could significantly alter their sensitivity to antibiotics. In our previous studies, Klebsiella pneumoniae showed major differences in the sensitivity to antibiotics in exposed and non-exposed samples. This study was aimed at investigating the alteration of antibiotic resistance of Klebsiella pneumonia, after exposure to Wi-Fi 2.4 GHz electromagnetic radiofrequency radiation. Materials and Methods In this in vitro study, three replicate agar plates were used for each test. The antibiotic susceptibility test was carried out using disc diffusion method on Mueller Hinton agar plates and the inhibition zones in both control and exposed groups were measured. A common Wi-Fi router was used in this study as the radiofrequency exposure source. Irradiated samples were exposed to Wi-Fi radiofrequency radiation for 3, 4.5 and 8 hours. Results Statistically significant variations of sensitivity to antibiotics were found for all studied antibiotics after 4.5 hours of RF exposure, compared to non-exposed bacteria. Interestingly, the mean diameters of the inhibition zones after 3 hours of exposure were less than those exposed for 4.5 hours. Following this rise in the sensitivity to antibiotics, a fall was observed in the bacteria exposed for 8 hours for all studied antibiotics. Conclusion The findings of this study show a statistically significant rise in the sensitivity of Klebsiella pneumoniae to different antibiotics after 4.5 hours of exposure to 2.4 GHz Wi-Fi radiation, followed by a fall after 8 hours of exposure. These observations can be interpreted by the concept of non-linearity in the responses of Klebsiella pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency radiation. As in this study a minimum level of effect was needed for the

  14. Modeling Klebsiella pneumoniae pathogenesis by infection of the wax moth Galleria mellonella.

    PubMed

    Insua, José Luis; Llobet, Enrique; Moranta, David; Pérez-Gutiérrez, Camino; Tomás, Anna; Garmendia, Junkal; Bengoechea, José A

    2013-10-01

    The implementation of infection models that approximate human disease is essential for understanding pathogenesis at the molecular level and for testing new therapies before they are entered into clinical stages. Insects are increasingly being used as surrogate hosts because they share, with mammals, essential aspects of the innate immune response to infections. We examined whether the larva of the wax moth Galleria mellonella could be used as a host model to conceptually approximate Klebsiella pneumoniae-triggered pneumonia. We report that the G. mellonella model is capable of distinguishing between pathogenic and nonpathogenic Klebsiella strains. Moreover, K. pneumoniae infection of G. mellonella models some of the known features of Klebsiella-induced pneumonia, i.e., cell death associated with bacterial replication, avoidance of phagocytosis by phagocytes, and the attenuation of host defense responses, chiefly the production of antimicrobial factors. Similar to the case for the mouse pneumonia model, activation of innate responses improved G. mellonella survival against subsequent Klebsiella challenge. Virulence factors necessary in the mouse pneumon