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1

Stenotrophomonas maltophilia in Lower Respiratory Tract Infections  

PubMed Central

Background: Stenotrophomonas maltophilia infection is gaining importance as an important cause of nosocomial pneumonia due to its characteristic inherent resistance to many broad- spectrum antibiotics. In this study we evaluated the demographic, clinical and microbiological profile of patients with lower respiratory tract infection due to Stenotrophomonas maltophilia. Materials and Methods: A retrospective analysis of 33 patients diagnosed with Stenotrophomonas maltophilia lower respiratory tract infections during a period of two years from 2012 - 2013 was done. Results: The predominant predisposing factor observed was mechanical ventilation in 17(51.5%) cases. Fluoroquinolones were the most effective antibiotic (26;78.8%) followed by trimethoprim-sulfamethoxazole (24;72.7%). Among the 19 patients treated with proper antibiotic, 13(68.4%) showed clinical improvement. Among the 14 patients who did not receive appropriate antibiotic for Stenotrophomonas maltophilia infection, 8(57.1%) showed improvement. Two (6%) had blood culture positive for Stenotrophomonas maltophilia. Mortality rate was 21.2%. Conclusion: Stenotrophomonas maltophilia is emerging as an important nosocomial pathogen with increased risk in patients on mechanical ventilation in ICU. Empiric therapy should include agents active against S.maltophilia such as newer flouroquinolones and trimethoprim-sulfamethoxazole. PMID:25653948

Vishwanath, Shashidhar; Gupta, Ashu

2014-01-01

2

Stenotrophomonas maltophilia: an Emerging Global Opportunistic Pathogen  

PubMed Central

Summary: Stenotrophomonas maltophilia is an emerging multidrug-resistant global opportunistic pathogen. The increasing incidence of nosocomial and community-acquired S. maltophilia infections is of particular concern for immunocompromised individuals, as this bacterial pathogen is associated with a significant fatality/case ratio. S. maltophilia is an environmental bacterium found in aqueous habitats, including plant rhizospheres, animals, foods, and water sources. Infections of S. maltophilia can occur in a range of organs and tissues; the organism is commonly found in respiratory tract infections. This review summarizes the current literature and presents S. maltophilia as an organism with various molecular mechanisms used for colonization and infection. S. maltophilia can be recovered from polymicrobial infections, most notably from the respiratory tract of cystic fibrosis patients, as a cocolonizer with Pseudomonas aeruginosa. Recent evidence of cell-cell communication between these pathogens has implications for the development of novel pharmacological therapies. Animal models of S. maltophilia infection have provided useful information about the type of host immune response induced by this opportunistic pathogen. Current and emerging treatments for patients infected with S. maltophilia are discussed. PMID:22232370

2012-01-01

3

Stenotrophomonas maltophilia: Complicating treatment of ESBL UTI.  

PubMed

Stenotrophomonas maltophilia (S. maltophilia) is a gram-negative bacillus emerging as an opportunistic, nosocomial pathogen associated with a high mortality rate. The organism has been shown to survive several biocides used in the hospital setting. Hospital water sources can serve as a reservoir for S. maltophilia. The transmission of S. maltophilia to susceptible individuals may occur through direct contact with the source or through the hands of health care personnel. S. maltophilia is usually resistant to third-generation cephalosporins, aminoglycosides and antipseudomonal penicillins. These microorganisms are intrinsically resistant to carbapenems, and exposure to these agents has been linked to selection of S. maltophilia. There have also been reports of the organism developing resistance to trimethoprim-sulfamethoxazole (TMP-SMX), which was initially considered as the drug of choice for S. maltophillia infections. We describe a case of nosocomial urinary tract infection (UTI) due to S. maltophilia in a diabetic patient, which the patient developed during treatment with meropenem for UTI due to Klebsiella pneumonia that was resistant to TMP-SMX. PMID:25789262

Kumar, Simit; Bandyopadhyay, Maitreyi; Chatterjee, Mitali; Banerjee, Parthajit; Poddar, Sumon; Banerjee, Debarati

2015-01-01

4

Stenotrophomonas maltophilia: Complicating treatment of ESBL UTI  

PubMed Central

Stenotrophomonas maltophilia (S. maltophilia) is a gram-negative bacillus emerging as an opportunistic, nosocomial pathogen associated with a high mortality rate. The organism has been shown to survive several biocides used in the hospital setting. Hospital water sources can serve as a reservoir for S. maltophilia. The transmission of S. maltophilia to susceptible individuals may occur through direct contact with the source or through the hands of health care personnel. S. maltophilia is usually resistant to third-generation cephalosporins, aminoglycosides and antipseudomonal penicillins. These microorganisms are intrinsically resistant to carbapenems, and exposure to these agents has been linked to selection of S. maltophilia. There have also been reports of the organism developing resistance to trimethoprimsulfamethoxazole (TMPSMX), which was initially considered as the drug of choice for S. maltophillia infections. We describe a case of nosocomial urinary tract infection (UTI) due to S. maltophilia in a diabetic patient, which the patient developed during treatment with meropenem for UTI due to Klebsiella pneumonia that was resistant to TMPSMX.

Kumar, Simit; Bandyopadhyay, Maitreyi; Chatterjee, Mitali; Banerjee, Parthajit; Poddar, Sumon; Banerjee, Debarati

2015-01-01

5

Heavy Metal Tolerance in Stenotrophomonas maltophilia  

PubMed Central

Stenotrophomonas maltophilia is an aerobic, non-fermentative Gram-negative bacterium widespread in the environment. S. maltophilia Sm777 exhibits innate resistance to multiple antimicrobial agents. Furthermore, this bacterium tolerates high levels (0.1 to 50 mM) of various toxic metals, such as Cd, Pb, Co, Zn, Hg, Ag, selenite, tellurite and uranyl. S. maltophilia Sm777 was able to grow in the presence of 50 mM selenite and 25 mM tellurite and to reduce them to elemental selenium (Se0) and tellurium (Te0) respectively. Transmission electron microscopy and energy dispersive X-ray analysis showed cytoplasmic nanometer-sized electron-dense Se0 granules and Te0 crystals. Moreover, this bacterium can withstand up to 2 mM CdCl2 and accumulate this metal up to 4% of its biomass. The analysis of soluble thiols in response to ten different metals showed eightfold increase of the intracellular pool of cysteine only in response to cadmium. Measurements by Cd K-edge EXAFS spectroscopy indicated the formation of Cd-S clusters in strain Sm777. Cysteine is likely to be involved in Cd tolerance and in CdS-clusters formation. Our data suggest that besides high tolerance to antibiotics by efflux mechanisms, S. maltophilia Sm777 has developed at least two different mechanisms to overcome metal toxicity, reduction of oxyanions to non-toxic elemental ions and detoxification of Cd into CdS. PMID:18253487

Pages, Delphine; Rose, Jerome; Conrod, Sandrine; Cuine, Stephane; Carrier, Patrick; Heulin, Thierry; Achouak, Wafa

2008-01-01

6

Community-acquired Stenotrophomonas maltophilia infections: a systematic review  

Microsoft Academic Search

Stenotrophomonas maltophilia is a pathogen that causes infections mainly in immunocompromised patients. However, community-acquired S. maltophilia infections have been occasionally reported. The objective of this paper was to collect and evaluate the available published\\u000a data referring to community-acquired S. maltophilia infections. We searched PubMed, the Cochrane Library, and Scopus for articles providing data for patients with community-acquired\\u000a S. maltophilia infections.

M. E. Falagas; A. C. Kastoris; E. K. Vouloumanou; G. Dimopoulos

2009-01-01

7

Structure of Aminodeoxychorismate Synthase from Stenotrophomonas maltophilia  

PubMed Central

PabB, aminodeoxychorismate synthase, is the chorismic acid binding component of the heterodimeric PabAB complex that converts chorismic acid to 4-amino-4-deoxychorismate, a precursor of p-aminobenzoate and folic acid in microorganisms. The second component, a glutamine amidotransferase subunit, PabA, generates ammonia that is channeled to the PabB active site where it attacks the C4 carbon of a chorismate derived intermediate that is covalently bound, through C2, to an active site lysine residue. The presence of a PIKGT motif was, until recently, believed to be discriminate PabB enzymes from the closely related enzyme anthranilate synthase, which typically contains a PIAGT active site motif and does not form a covalent enzyme-substrate intermediate with chorismate. A subclass of PabB enzymes that employ an alternative mechanism requiring two equivalents of ammonia from glutamine and that feature a noncovalently bound 2-amino-2-deoxyisochorismate intermediate was recently identified. Here we report the 2.25 crystal structure of PabB from the emerging pathogen Stenotrophomonas maltophilia. It is the first reported structure of a PabB that features the PIAGT motif. Surprisingly, no dedicated pabA is evident in the genome of S. maltophilia suggesting that another cellular amidotransferase is able to fulfill the role of PabA in this organism. Evaluation of the ammonia-dependent aminodeoxychorismate synthase activity of S. maltophilia PabB alone revealed that it is virtually inactive. However, in the presence of a heterologous PabA surrogate, typical levels of activity were observed using either glutamine or ammonia as the nitrogen source. Additionally, the structure suggests that a key segment of the polypeptide can remodel itself to interact with a nonspecialized or shared amidotransferase partner in vivo. The structure and mass spectral analysis further suggest that S. maltophilia PabB, like Escherichia coli PabB, binds tryptophan in a vestigial regulatory site. The observation that the binding site is unoccupied in the crystal structure, however, suggests the affinity may be low relative to E. coli PabB. PMID:23230967

Bera, Asim K.; Atanasova, Vesna; Dhanda, Anjali; Ladner, Jane E.; Parsons, James F.

2012-01-01

8

Stenotrophomonas maltophilia: an emerging pathogen in dialysis units.  

PubMed

Infection is an important cause of morbidity and mortality among patients with end stage renal disease. Stenotrophomonas maltophilia is an unusual yet emerging pathogen in dialysis units. We performed a systematic PubMed/Medline and Scopus review of peer-reviewed English papers on S. maltophilia infections among patients undergoing chronic dialysis, with regard to vascular accesses, systemic infections and environment contaminations. Moreover, we suggest a treatment algorithm to preserve the patient and the permanent dialysis catheters. PMID:25102909

De Mauri, Andreana; Torreggiani, Massimo; Chiarinotti, Doriana; Andreoni, Stefano; Molinari, Gianlorenzo; De Leo, Martino

2014-11-01

9

Microbiological and Clinical Aspects of Infection Associated with Stenotrophomonas maltophilia  

PubMed Central

The gram-negative bacterium Stenotrophomonas maltophilia is increasingly recognized as an important cause of nosocomial infection. Infection occurs principally, but not exclusively, in debilitated and immunosuppressed individuals. Management of S. maltophilia-associated infection is problematic because many strains of the bacterium manifest resistance to multiple antibiotics. These difficulties are compounded by methodological problems in in vitro susceptibility testing for which there are, as yet, no formal guidelines. Despite its acknowledged importance as a nosocomial pathogen, little is known of the epidemiology of S. maltophilia, and although it is considered an environmental bacterium, its sources and reservoirs are often not readily apparent. Molecular typing systems may contribute to our knowledge of the epidemiology of S. maltophilia infection, thus allowing the development of strategies to interrupt the transmission of the bacterium in the hospital setting. Even less is known of pathogenic mechanisms and putative virulence factors involved in the natural history of S. maltophilia infection and this, coupled with difficulties in distinguishing colonization from true infection, has fostered the view that the bacterium is essentially nonpathogenic. This article aims to review the current taxonomic status of S. maltophilia, and it discusses the laboratory identification of the bacterium. The epidemiology of the organism is considered with particular reference to nosocomial outbreaks, several of which have been investigated by molecular typing techniques. Risk factors for acquisition of the bacterium are also reviewed, and the ever-expanding spectrum of clinical syndromes associated with S. maltophilia is surveyed. Antimicrobial resistance mechanisms, pitfalls in in vitro susceptibility testing, and therapy of S. maltophilia infections are also discussed. PMID:9457429

Denton, Miles; Kerr, Kevin G.

1998-01-01

10

Stenotrophomonas maltophilia endogenous endophthalmitis: clinical presentation, antibiotic susceptibility, and outcomes  

PubMed Central

Objective To describe clinical presentation, antibiotic susceptibility, and outcomes in patients with Stenotrophomonas maltophilia endogenous endophthalmitis. Design Retrospective case series. Participants Four eyes of four patients with S. maltophilia endogenous endophthalmitis. Methods Retrospective chart review of culture-positive S. maltophilia endogenous endophthalmitis treated at L V Prasad Eye Institute, Hyderabad, India, between January 2007 and December 2012, was done. Collected information included demographic, clinical, and microbiology data. Results These four patients with S. maltophilia endogenous endophthalmitis cases accounted for 0.47% (4/836) of total bacterial endophthalmitis cases treated in this period. All patients were from a rural setting and younger than 40 years. Two of the four patients had a history of immune compromise or hospitalization. The visual acuity at presentation was less than 20/320 in all patients. Common presenting features were severe anterior and posterior segment inflammation and hypopyon. All patients underwent vitrectomy with injection of intravitreal antibiotics and dexamethasone. Direct microscopy of the vitreous sample was positive in all cases. All isolates were sensitive to fluoroquinolones and chloramphenicol; sensitivity to aminoglycosides and third-generation cephalosporins was highly variable. The final visual acuity was 20/80 or more in three patients. The time to presentation did not seem to influence the visual or anatomical outcome. Conclusion S. maltophilia is a rare cause of endogenous endophthalmitis and usually occurs in young and apparently healthy individuals. Clinical presentation is moderate to severe, and recovery is variable. Fourth-generation fluoroquinolones and chloramphenicol were the most sensitive antibiotics against S. maltophilia in this series of patients. PMID:25170244

Chhablani, Jay; Sudhalkar, Aditya; Jindal, Animesh; Das, Taraprasad; Motukupally, Swapna R; Sharma, Savitri; Pathengay, Avinash; Flynn, Harry W

2014-01-01

11

Dengue co-infection in a blood stream infection caused by Stenotrophomonas maltophilia: A case report.  

PubMed

Stenotrophomonas maltophilia (S. maltophilia) is an emerging opportunistic bacterial pathogen with resistance to several commonly used antibiotics. Owing to its multidrug resistance (MDR), management of S. maltophilia blood stream infection (BSI) is challenging and requires the selection of appropriate antibiotic therapy. The presence of thrombocytopenia and shock are independent risk factors associated with increased mortality in patients with S. maltophilia BSI. We describe an unusual case of S. maltophilia BSI in a middle-age female complicated by dengue fever. We highlight the importance of early recognition of both dengue and S. maltophilia infection in management of such cases. PMID:25550715

Srirangaraj, Sreenivasan; Kali, Arunava; Vijayan, Sivaranjini

2014-01-01

12

Multiple degradation pathways of phenanthrene by Stenotrophomonas maltophilia C6  

PubMed Central

Stenotrophomonas maltophilia strain C6, capable of utilizing phenanthrene as a sole source of carbon and energy, was isolated from creosote-contaminated sites at Hilo, Hawaii. Twenty-two metabolites of phenanthrene, covering from dihydrodiol to protocatechuic acid, were isolated and characterized. Phenanthrene was degraded via an initial dioxygenation on 1,2-, 3,4-, and 9,10-C, where the 3,4-dioxygenation and subsequent metabolisms were most dominant. The metabolic pathways were further branched by ortho- and meta-cleavage of phenanthrenediols to produce 1-hydroxy-2-naphthoic acid, 2-hydroxy-1-naphthoic acid, and naphthalene-1,2-dicarboxylic acid. These intermediates were then transformed to naphthalene-1,2-diol. 1-Hydroxy-2-naphthoic acid was also degraded via a direct ring cleavage. Naphthalene-1,2-diol underwent primarily ortho-cleavage to produce trans-2-carboxycinnamic acid and then to form phthalic acid, 4,5-dihydroxyphthalic acid and protocatechuic acid. Accumulation of salicylic acid in prolonged incubation indicated that a limited extent of meta-cleavage of naphthalene-1, 2-diol also occurred. This is the first study of detailed phenanthrene metabolic pathways by Stenotrophomonas maltophilia. PMID:23539472

Gao, Shumei; Seo, Jong-Su; Wang, Jun; Keum, Young-Soo; Li, Jianqiang; Li, Qing X.

2013-01-01

13

Molecular epidemiology of Burkholderia cepacia, Stenotrophomonas maltophilia , and Alcaligenes xylosoxidans in a cystic fibrosis center  

Microsoft Academic Search

Burkholderia cepacia, Stenotrophomonas maltophilia, andAlcaligenes xylosoxidans have been isolated with increasing frequency from the sputum of patients with cystic fibrosis in a pediatric hospital. In 199495, 27 of 120 patients were persistently colonized, 17 withBurkholderia cepacia, eight withAlcaligenes xylosoxidans, and five withStenotrophomonas maltophilia. Genotyping of 220 clinical isolates revealed that most of theBurkholderia cepacia strains were clonally related, suggesting either

H. Vu-Thien; D. Moissenet; M. Valcin; C. Dulot; G. Tournier; A. Garbarg-Chenon

1996-01-01

14

Molecular characterization of 2-chlorobiphenyl degrading Stenotrophomonas maltophilia GS-103.  

PubMed

The catabolic potential of transformer oil contaminated soil bacteria in aerobic degradation of polychlorinated biphenyls (PCB) were assessed. Transformer oil contaminated soil sample was subjected to microcosm enrichment experiments (PAS medium/biphenyl as sole carbon source). PCB-degrading activity of the enrichment cultures in PAS medium with the addition of 2-chlorobiphenyl were analysed by GC-MS indicated that, although the isolates differed in PCB-degrading capabilities, all of the enrichment cultures expressed activity toward at least some of the lower chlorinated congeners. Biphenyl-utilizing bacteria isolated from the most active PCB-degrading mixed cultures showed little taxonomic diversity and identified as Stenotrophomonas maltophilia GS-103. PMID:23801320

Somaraja, P K; Gayathri, D; Ramaiah, N

2013-08-01

15

Antibiotic combinations significantly more active than monotherapy in an in vitro infection model of Stenotrophomonas maltophilia  

Microsoft Academic Search

The goal of this study was to investigate clinical doses of trimethoprimsulfamethoxazole (TMPSMX) alone and in combination against Stenotrophomonas maltophilia in an in vitro pharmacodynamic infection model. A 1-compartment model was established using 4 clinical isolates of S. maltophilia susceptible to TMPSMX and susceptible or intermediately susceptible to at least one other agent (ie, ceftazidime, ciprofloxacin, gentamicin, tobramycin). Antibiotics alone

Sheryl A. Zelenitsky; Harris Iacovides; Robert E. Ariano; Godfrey K. M. Harding

2005-01-01

16

Enhanced Degradation of TNT by Genome-Shuffled Stenotrophomonas maltophilia OK5  

Microsoft Academic Search

In this study, the enhanced degradation of TNT using cultures of genome-shuffled Stenotrophomonas maltophilia OK-5 mt-3 has been examined and the proteome of shuffled strain was compared to the wild-type OK-5 strain. Genome shuffling\\u000a of S. maltophilia OK-5 was used to achieve a rapid enhancement of TNT degradation. The initial mutant population was generated by NTG treatment\\u000a and UV irradiation.

Bheong-Uk Lee; Yun-Seok Cho; Sung-Chul Park; Kye-Heon Oh

2009-01-01

17

Functional characterization of the RNA chaperone Hfq in the opportunistic human pathogen Stenotrophomonas maltophilia.  

PubMed

Hfq is an RNA-binding protein known to regulate a variety of cellular processes by interacting with small RNAs (sRNAs) and mRNAs in prokaryotes. Stenotrophomonas maltophilia is an important opportunistic pathogen affecting primarily hospitalized and immunocompromised hosts. We constructed an hfq deletion mutant (?hfq) of S. maltophilia and compared the behaviors of wild-type and ?hfq S. maltophilia cells in a variety of assays. This revealed that S. maltophilia Hfq plays a role in biofilm formation and cell motility, as well as susceptibility to antimicrobial agents. Moreover, Hfq is crucial for adhesion to bronchial epithelial cells and is required for the replication of S. maltophilia in macrophages. Differential RNA sequencing analysis (dRNA-seq) of RNA isolated from S. maltophilia wild-type and ?hfq strains showed that Hfq regulates the expression of genes encoding flagellar and fimbrial components, transmembrane proteins, and enzymes involved in different metabolic pathways. Moreover, we analyzed the expression of several sRNAs identified by dRNA-seq in wild-type and ?hfq S. maltophilia cells grown in different conditions on Northern blots. The accumulation of two sRNAs was strongly reduced in the absence of Hfq. Furthermore, based on our dRNA-seq analysis we provide a genome-wide map of transcriptional start sites in S. maltophilia. PMID:22923593

Roscetto, Emanuela; Angrisano, Tiziana; Costa, Valerio; Casalino, Mariassunta; Frstner, Konrad U; Sharma, Cynthia M; Di Nocera, Pier Paolo; De Gregorio, Eliana

2012-11-01

18

Susceptibility of Stenotrophomonas maltophilia clinical strains in China to antimicrobial combinations.  

PubMed

We aimed to investigate the activity levels of several combinations of antimicrobials against Stenotrophomonas maltophilia. In this study, the antimicrobial susceptibility of S. maltophilia clinical isolates was determined, and the synergistic activity of three pairs of antimicrobial combinations was evaluated by the fractional inhibitory concentration index (FICI). The antimicrobial susceptibility in vitro against 83 S. maltophilia strains was greater for minocycline (807%) than for trimethoprim-sulfamethoxazole (518%), and levofloxacin (506%). The rate of resistance was highest for ticarcillin-clavulanate and ceftazidime (638%) and resistance to trimethoprim-sulfamethoxazole (TMP-SMX) was 482%. All three combinations were tested against susceptible isolates. Two of the combinations, TMP-SMX+ceftazidime and levofloxacin+ceftazidime were more effective than the combination of TMP-SMX+levofloxacin. We recommend acquiring more clinical data in order to explore combination therapy, which is a promising treatment of S. maltophilia infections. PMID:24588423

Hu, Li-Fen; Gao, Li-Ping; Ye, Ying; Chen, Xi; Zhou, Xiang-Tian; Yang, Hai-Fei; Liiu, Yan-Yan; Mei, Qing; Li, Jia-Bin

2014-10-01

19

Highly efficient transformation of Stenotrophomonas maltophilia S21, an environmental isolate from soil, by electroporation.  

PubMed

Stenotrophomonas maltophilia is an emerging opportunistic pathogen, which also exhibits potential of wide applications in industry, environment and agriculture. An efficient transformation method for S. maltophilia would be convenient to its genetic studies. In this report, we focused on developing an efficient transformation protocol for S. maltophilia. Gene transfer by three different methods (chemical transformation, conjugation and electroporation) indicated that electroporation was the most efficient method to transform S. maltophilia S21. Then, the entire electroporation process from competent-cell preparation to post-pulse incubation was optimized to get higher efficiencies. Utilizing competent cells prepared at optical density (600 nm) of 1.0, the maximal transformation efficiency of S. maltophilia S21 reached 1.53 10(8) transformants/?g of pBBR1MCS DNA at a field strength of 18 kV/cm, a time constant of 4.8 ms (200 ?), a DNA amount of 100 ng and a cell concentration of 2.4 10(8) CFU/ml after 3 h incubation. Moreover, we successfully transformed the other four isolates of S. maltophilia using this protocol. To date, this is the first report about electroporation of S. maltophilia and it will facilitate the further study of this species. PMID:25300664

Ye, Xing; Dong, Hongling; Huang, Yu-Ping

2014-12-01

20

Stenotrophomonas maltophilia and Vermamoeba vermiformis relationships: bacterial multiplication and protection in amoebal-derived structures.  

PubMed

Stenotrophomonas maltophilia, a bacteria involved in healthcare-associated infections, can be found in hospital water systems. Other microorganisms, such as Free Living amoebae (FLA), are also at times recovered in the same environment. Amongst these protozoa, many authors have reported the presence of Vermamoeba vermiformis. We show here that this amoeba enhances S. maltophilia growth and harbors the bacteria in amoebal-derived structures after 28 days in harsh conditions. These results highlight the fact that particular attention should be paid to the presence of FLA in hospital water systems, because of their potential implication in survival and growth of pathogenic bacterial species. PMID:25463386

Cateau, Estelle; Maisonneuve, Elodie; Peguilhan, Samuel; Quellard, Nathalie; Hechard, Yann; Rodier, Marie-Helene

2014-12-01

21

Structure of the O2O antigen of Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia  

Microsoft Academic Search

The O-antigen polymer recovered from the reference strain for Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia serogroup O2O, by mild acid hydrolysis of the lipopolysaccharide, was found to contain d-rhamnose and d-mannose. By means of chemical degradations and NMR studies, the repeating-unit of the polymer was deduced to be a linear tetrasaccharide with the structure shown. ?-?-d-Manp-(1?3)-?d-Rhap-(1?2)-?d-Rhap-(1?

Angela M. Winn; Stephen G. Wilkinson

1996-01-01

22

Characterization of Maltocin P28, a Novel Phage Tail-Like Bacteriocin from Stenotrophomonas maltophilia  

PubMed Central

Stenotrophomonas maltophilia is an important global opportunistic pathogen for which limited therapeutics are available because of the emergence of multidrug-resistant strains. A novel bacteriocin, maltocin P28, which is produced by S. maltophilia strain P28, may be the first identified phage tail-like bacteriocin from S. maltophilia. Maltocin P28 resembles a contractile but nonflexible phage tail structure based on electron microscopy, and it is sensitive to trypsin, proteinase K, and heat. SDS-PAGE analysis of maltocin P28 revealed two major protein bands of approximately 43 and 20 kDa. The N-terminal amino acid residues of these two major subunits were sequenced, and the maltocin P28 gene cluster was located on the S. maltophilia P28 chromosome. Our sequence analysis results indicate that this maltocin gene cluster consists of 23 open reading frames (ORFs), and that its gene organization is similar to that of the P2 phage genome and R2 pyocin gene cluster. ORF17 and ORF18 encode the two major structural proteins, which correspond to gpFI (tail sheath) and gpFII (tail tube) of P2 phage, respectively. We found that maltocin P28 had bactericidal activity against 38 of 81 tested S. maltophilia strains. Therefore, maltocin P28 is a promising therapeutic substitute for antibiotics for S. maltophilia infections. PMID:23835182

Liu, Jian; Chen, Peng; Zheng, Congyi

2013-01-01

23

Stenotrophomonas Maltophilia Endophthalmitis Caused by Surgical Equipment Contamination: an Emerging Nosocomial Infection  

PubMed Central

Purpose: We report three cases of Stenotrophomonas maltophilia endophthalmitis after uneventful extracapsular cataract extraction with intraocular lens implantation-related to surgical equipment contamination. Case report: All patients developed acute, culture-positive endophthalmitis in a period ranging from 2 to 13 days. Cultures from vitreous tap, as well as those obtained from the hand-piece of the irrigation-aspiration system, revealed S. maltophilia as the causing infectious agent. All patients received intravitreal antibiotic treatment as initial therapy, nevertheless, visual disturbance continued to be present, hence pars plana vitrectomy was required. Conclusion: Contamination of surgical-reusable equipment should be considered in addition to the well-known risk factors associated with development of endophthalmitis by S. maltophilia. PMID:25667741

Williams, Maria A.; Gramajo, Ana L.; Colombres, Gustavo A.; Caeiro, Juan P.; Jurez, Claudio P.; Luna, Jos D.

2014-01-01

24

Virulence of environmental Stenotrophomonas maltophilia serologically cross-reacting with Shigella-specific antisera.  

PubMed

This research involved an environmental strain of Stenotrophomonas maltophilia which has been reported to produce serological cross-reactivity with Shigella dysenteriae type 8 specific antisera. Since clinical diagnosis of shigellosis is largely based on culture and serology, the investigation was aimed at in vivo and in vitro virulence comparison between the culturally similar environmental S. maltophilia isolate and the reference S. dysenteriae strains. The findings of this study revealed the absence of virulent genes of Shigella sp. like ipaH, virA and stx1 and characteristic invasive large plasmid in the test isolate. The Western blot analysis revealed that serological cross-reactivity of Stenotrophomonas maltophilia was due to certain protein component(s) in its outer membrane. The isolate was capable of producing extracellular protease, exhibited alpha hemolysis and was negative for hemagglutinating assay. The isolate gave negative reaction with rabbit ileal loop and Sereny tests. The S. maltophilia isolate did not possess any enterotoxic or invasive property as that of virulent S. dysenteriae strains. Further characterizations and adequate genetic manipulations of this environmental isolate may contribute to the development of a potential vaccine candidate for shigellosis. PMID:21313916

Bonny, T S; Azmuda, N; Khan, S I; Birkeland, N K; Rahman, M Z

2010-10-01

25

Stenotrophomonas maltophilia Infection Among Young Children in a Cardiac Intensive Care Unit: A Single Institution Experience.  

PubMed

Stenotrophomonas maltophilia can present as bacteremia, respiratory tract infection, urinary tract infection, soft tissue and wound infections, bone and joint infections, meningitis, and endocarditis especially in immunosuppressed patients and those with underlying medical conditions. The incidence and impact of S. maltophilia in young children with heart disease are poorly defined. A single center retrospective observational study was conducted in infants <180days of age with positive S. maltophilia cultures over a period of 5years. The overall incidence for S. maltophilia infection was 0.8% (n=32/3656). Among 32 identified infants, there were 47 episodes of S. maltophilia infection 66% of infants had prior exposure to broad spectrum antibiotics. 97% of positive isolates were susceptible to trimethoprim/sulfamethoxazole and 91% to levofloxacin as well as ticarcillin/clavulanate. Ventilator-free days and absolute lymphocyte count prior to acquiring infection were significantly lower in non-survivors than in survivors. 100% of survivors had clearance of positive cultures compared to 50% in non-survivors (p<0.05). The crude all-cause mortality rate was 37.5%. All non-survivors had increased length of ICU stay and duration of mechanical ventilation and had delayed clearance of infection and required longer duration of treatment. PMID:25293429

Arthur, Ciji; Tang, Xinyu; Romero, Jose R; Gossett, Jeffrey G; Harik, Nada; Prodhan, Parthak

2015-03-01

26

Genotypic and Phenotypic Relationships between Clinical and Environmental Isolates of Stenotrophomonas maltophilia  

PubMed Central

While the gram-negative bacterium Stenotrophomonas maltophilia is used in biotechnology (e.g., for biological control of plant pathogens and for bioremediation), the number of S. maltophilia diseases in humans has dramatically increased in recent years. A total of 40 S. maltophilia isolates from clinical and environmental sources (plant associated and water) was investigated to determine the intraspecies diversity of the group and to determine whether or not the strains could be grouped based on the source of isolation. The isolates were investigated by phenotypic profiling (enzymatic and metabolic activity and antibiotic resistance patterns) and by molecular methods such as temperature-gradient gel electrophoresis of the 16S rRNA gene fragment, PCR fingerprinting with BOX primers, and pulsed-field gel electrophoresis (PFGE) after digestion with DraI. Results of the various methods revealed high intraspecies diversity. PFGE was the most discriminatory method for typing S. maltophilia when compared to the other molecular methods. The environmental strains of S. maltophilia were highly resistant to antibiotics, and the resistance profile pattern of the strains was not dependent on their source of isolation. Computer-assisted cluster analysis of the phenotypic and genotypic features did not reveal any clustering patterns for either clinical or environmental isolates. PMID:10523559

Berg, Gabriele; Roskot, Nicolle; Smalla, Kornelia

1999-01-01

27

Stenotrophomonas maltophilia Infections in a General Hospital: Patient Characteristics, Antimicrobial Susceptibility, and Treatment Outcome  

PubMed Central

Introduction Stenotrophomonas maltophilia is acquiring increasing importance as a nosocomial pathogen. Methods We retrospectively studied the characteristics and outcome of patients with any type of S. maltophilia infection at the University Hospital of Heraklion, Crete, Greece, between 1/200512/2010. S. maltophilia antimicrobial susceptibility was tested with the agar dilution method. Prognostic factors for all-cause in-hospital mortality were assessed with multivariate logistic regression. Results Sixty-eight patients (median age: 70.5 years; 64.7% males) with S. maltophilia infection, not related to cystic fibrosis, were included. The 68 patients were hospitalized in medical (29.4%), surgical (26.5%), hematology/oncology departments (23.5%), or the intensive care units (ICU; 20.6%). The most frequent infection types were respiratory tract (54.4%), bloodstream (16.2%), skin/soft tissue (10.3%), and intra-abdominal (8.8%) infection. The S. maltophilia-associated infection was polymicrobial in 33.8% of the cases. In vitro susceptibility was higher to colistin (91.2%), trimethoprim/sulfamethoxazole and netilmicin (85.3% each), and ciprofloxacin (82.4%). The empirical and the targeted treatment regimens were microbiologically appropriate for 47.3% and 63.6% of the 55 patients with data available, respectively. Most patients received targeted therapy with a combination of agents other than trimethoprim/sulfamethoxazole. The crude mortality and the mortality and the S. maltophilia infection-related mortality were 14.7% and 4.4%, respectively. ICU hospitalization was the only independent prognostic factor for mortality. Conclusion S. maltophilia infection in a general hospital can be associated with a good prognosis, except for the patients hospitalized in the ICU. Combination reigmens with fluoroquinolones, colistin, or tigecycline could be alternative treatment options to trimethoprim/sulfamethoxazole. PMID:22624022

Samonis, George; Karageorgopoulos, Drosos E.; Maraki, Sofia; Levis, Panagiotis; Dimopoulou, Dimitra; Spernovasilis, Nikolaos A.; Kofteridis, Diamantis P.; Falagas, Matthew E.

2012-01-01

28

SmeOP-TolCSm efflux pump contributes to the multidrug resistance of Stenotrophomonas maltophilia.  

PubMed

A five-gene cluster, tolCSm-pcm-smeRo-smeO-smeP, of Stenotrophomonas maltophilia was characterized. The presence of smeOP and smeRo-pcm-tolCSm operons was verified by reverse transcription (RT)-PCR. Both operons were negatively regulated by the TetR-type transcriptional regulator SmeRo, as demonstrated by quantitative RT-PCR and a promoter-fusion assay. SmeO and SmeP were associated with TolCSm (the TolC protein of S. maltophilia) for the assembly of a resistance-nodulation-cell-division (RND)-type pump. The compounds extruded by SmeOP-TolCSm mainly included nalidixic acid, doxycycline, amikacin, gentamicin, erythromycin, leucomycin, carbonyl cyanide 3-chlorophenylhydrazone, crystal violet, sodium dodecyl sulfate, and tetrachlorosalicylanilide. PMID:24395237

Lin, Cheng-Wen; Huang, Yi-Wei; Hu, Rouh-Mei; Yang, Tsuey-Ching

2014-01-01

29

The sul1 Gene in Stenotrophomonas maltophilia With High-Level Resistance to Trimethoprim/Sulfamethoxazole  

PubMed Central

Emerging resistance to trimethoprim/sulfamethoxazole (SXT) poses a serious threat to the treatment of Stenotrophomonas maltophilia infections. We determined the prevalence and molecular characteristics of acquired SXT resistance in recent clinical S. maltophilia isolates obtained from Korea. A total of 252 clinical isolates of S. maltophilia were collected from 10 university hospitals in Korea between 2009 and 2010. Antimicrobial susceptibility was determined by using the CLSI agar dilution method. The sul1, sul2, and sul3 genes, integrons, insertion sequence common region (ISCR) elements, and dfrA genes were detected using PCR. The presence of the sul1 gene and integrons was confirmed through sequence analysis. Among the 32 SXT-resistant isolates, sul1 was detected in 23 isolates (72%), all of which demonstrated high-level resistance (?64 mg/L) to SXT. The sul1 gene (varying in size and structure) was linked to class 1 integrons in 15 of the 23 isolates (65%) harboring this gene. None of the SXT-susceptible isolates or the SXT-resistant isolates with a minimum inhibitory concentration of 4 and 8 mg/L were positive for sul1. Moreover, the sul2, sul3, and dfrA genes or the ISCR elements were not detected. The sul1 gene may play an important role in the high-level SXT resistance observed in S. maltophilia. PMID:25729729

Chung, Hae-Sun; Kim, Kyeongmi; Hong, Sang Sook; Lee, Kyungwon; Chong, Yunsop

2015-01-01

30

The sul1 Gene in Stenotrophomonas maltophilia With High-Level Resistance to Trimethoprim/Sulfamethoxazole.  

PubMed

Emerging resistance to trimethoprim/sulfamethoxazole (SXT) poses a serious threat to the treatment of Stenotrophomonas maltophilia infections. We determined the prevalence and molecular characteristics of acquired SXT resistance in recent clinical S. maltophilia isolates obtained from Korea. A total of 252 clinical isolates of S. maltophilia were collected from 10 university hospitals in Korea between 2009 and 2010. Antimicrobial susceptibility was determined by using the CLSI agar dilution method. The sul1, sul2, and sul3 genes, integrons, insertion sequence common region (ISCR) elements, and dfrA genes were detected using PCR. The presence of the sul1 gene and integrons was confirmed through sequence analysis. Among the 32 SXT-resistant isolates, sul1 was detected in 23 isolates (72%), all of which demonstrated high-level resistance (?64 mg/L) to SXT. The sul1 gene (varying in size and structure) was linked to class 1 integrons in 15 of the 23 isolates (65%) harboring this gene. None of the SXT-susceptible isolates or the SXT-resistant isolates with a minimum inhibitory concentration of 4 and 8 mg/L were positive for sul1. Moreover, the sul2, sul3, and dfrA genes or the ISCR elements were not detected. The sul1 gene may play an important role in the high-level SXT resistance observed in S. maltophilia. PMID:25729729

Chung, Hae-Sun; Kim, Kyeongmi; Hong, Sang Sook; Hong, Seong Geun; Lee, Kyungwon; Chong, Yunsop

2015-03-01

31

Stenotrophomonas maltophilia Induced Post-Cataract-Surgery Endophthalmitis: Outbreak Investigation and Clinical Courses of 26 Patients  

Microsoft Academic Search

\\u000a Abstract\\u000a \\u000a \\u000a Background:\\u000a \\u000a Stenotrophomonas maltophilia, a microorganism which colonizes plastic material, is a rare causative agent of iatrogenic endophthalmitis.\\u000a \\u000a \\u000a \\u000a \\u000a Patients and Methods:\\u000a A cluster of 26 cases of acute post-cataract-surgery endophthalmitis (PE) was identified. An outbreak investigation was performed.\\u000a Information was abstracted from patients charts and questionnaires sent to patients and their general practitioners. Vision\\u000a was examined before, during, as

S. Horster; L. Bader; U. Seybold; I. Eschler; K. G. Riedel; J. R. Bogner

2009-01-01

32

Chronic dacryocystitis secondary to Stenotrophomonas maltophilia and Staphylococcus aureus mixed infection.  

PubMed

A 40-year-old woman with a history of recurrent attacks of dacryocystitis for 2?years developed a lacrimal sac abscess. ?-Lactam antibiotics, considered the first-line treatment for dacryocystitis, were ineffective. She underwent dacryocystorhinostomy. Cultures from the lacrimal sac demonstrated the presence of Stenotrophomonas maltophilia and methicillin-sensitive Staphylococcus aureus, both of which are sensitive to trimethoprim-sulfamethoxazole. This rare and antibiotic-resistant bacterial species should be considered in atypical cases of dacryocystitis, and appropriate antibiotics should be started immediately. PMID:24951597

Comez, Arzu Taskiran; Koklu, Asiye; Akcali, Alper

2014-01-01

33

Facile biosynthesis of phosphate capped gold nanoparticles by a bacterial isolate Stenotrophomonas maltophilia  

NASA Astrophysics Data System (ADS)

We report intracellular biosynthesis of gold nanoparticles (GNPs) by a strain Stenotrophomonas maltophilia (AuRed02) isolated from the soil samples of Singhbhum gold mines, India. An aqueous solution of gold chloride was reduced to metallic gold in a suspension of disrupted cell mass of AuRed02, which progressively turns into cherry red within 8 h of incubation at 25 C. The optical spectrum showed the plasmon resonance at 530 nm and analysis by transmission electron microscopy and dynamic light scattering confirmed the formation of around 40 nm GNPs. Zeta potential and Fourier transform infrared measurements confirmed GNPs are capped by negatively charged phosphate groups of NADP.

Nangia, Yogesh; Wangoo, Nishima; Sharma, Saurabh; Wu, Jin-Song; Dravid, Vinayak; Shekhawat, G. S.; Raman Suri, C.

2009-06-01

34

Comparison of two multimetal resistant bacterial strains: Enterobacter sp. YSU and Stenotrophomonas maltophilia ORO2.  

PubMed

The Y-12 plant in Oak Ridge, TN, which manufactured nuclear weapons during World War II and the Cold War, contaminated East Fork Poplar Creek with heavy metals. The multimetal resistant bacterial strain, Stenotrophomonas maltophilia Oak Ridge strain O2 (S. maltophilia O2), was isolated from East Fork Poplar Creek. Sequence analysis of 16s rDNA suggested that our working strain of S. maltophilia O2 was a strain of Enterobacter. Phylogenetic tree analysis and biochemical tests confirmed that it belonged to an Enterobacter species. This new strain was named Enterobacter sp. YSU. Using a modified R3A growth medium, R3A-Tris, the Hg(II), Cd(II), Zn(II), Cu(II), Au(III), Cr(VI), Ag(I), As(III), and Se(IV) MICs for a confirmed strain of S. maltophilia O2 were 0.24, 0.33, 5, 5, 0.25, 7, 0.03, 14, and 40 mM, respectively, compared to 0.07, 0.24, 0.8, 3, 0.05, 0.4, 0.08, 14, and 40 mM, respectively, for Enterobacter sp. YSU. Although S. maltophilia O2 was generally more metal resistant than Enterobacter sp. YSU, in comparison to Escherichia coli strain HB101, Enterobacter sp. YSU was resistant to Hg(II), Cd(II), Zn(II), Au(III), Ag(I), As(III), and Se(IV). By studying metal resistances in these two strains, it may be possible to understand what makes one microorganism more metal resistant than another microorganism. This work also provided benchmark MICs that can be used to evaluate the metal resistance properties of other bacterial isolates from East Fork Poplar Creek and other metal contaminated sites. PMID:19688378

Holmes, Andrew; Vinayak, Anubhav; Benton, Cherise; Esbenshade, Aaron; Heinselman, Carlisle; Frankland, Daniel; Kulkarni, Samatha; Kurtanich, Adrienne; Caguiat, Jonathan

2009-11-01

35

The contribution of class 1 integron to antimicrobial resistance in Stenotrophomonas maltophilia.  

PubMed

Two hundred clinical isolates of Stenotrophomonas maltophilia were examined for the presence of class 1 integron and for the susceptibility to 12 different antimicrobials and detergents. The prevalence of class 1 integron in S. maltophilia isolates was 11%. The class 1 integron-positive isolates exhibited a higher resistance to kanamycin, tobramycin, and trimethoprim-sulfamethoxazole (SXT) than the class 1 integron-negative ones. Polymerase chain reaction (PCR), amplifying the variable region of the class 1 integron, showed the existence of six different amplicon sizes, indicating that there are at least six different class 1 integrons distributed in the 23 class 1 integron-positive isolates. Sequence analysis of six representative PCR amplicons revealed that qacK, aac(6')-Ib', qacK-aac(6')-Ib, qacK-aac(6')-Ib-aac(6')-Ib, and qacL-aadB-cmlA-aadA2 were identified in the 550-, 800-, 1,200-, 1,800, and 3,600-bp amplicons, respectively. The sequence analysis of the 150-bp PCR amplicon demonstrated no additional resistance-associated genes except the basic genetic elements of class 1 integron. The impact of class 1 integron acquisition on the antimicrobials susceptibility was assayed by isogenic integron deletion mutant construction and the susceptibility test. The most significant contribution of the class 1 integron acquisition to S. maltophilia is the increased resistance to SXT. PMID:25243757

Huang, Yi-Wei; Hu, Rouh-Mei; Lin, Yi-Tsung; Huang, Hsin-Hui; Yang, Tsuey-Ching

2015-02-01

36

Infections Caused by Stenotrophomonas maltophilia in Recipients of Hematopoietic Stem Cell Transplantation  

PubMed Central

Stenotrophomonas maltophilia (S. maltophilia) is a globally emerging Gram-negative bacillus that is widely spread in environment and hospital equipment. Recently, the incidence of infections caused by this organism has increased, particularly in patients with hematological malignancy and in recipients of hematopoietic stem cell transplantation (HSCT) having neutropenia, mucositis, diarrhea, central venous catheters or graft versus host disease and receiving intensive cytotoxic chemotherapy, immunosuppressive therapy, or broad-spectrum antibiotics. The spectrum of infections in HSCT recipients includes pneumonia, urinary tract and surgical site infection, peritonitis, bacteremia, septic shock, and infection of indwelling medical devices. The organism exhibits intrinsic resistance to many classes of antibiotics including carbapenems, aminoglycosides, most of the third-generation cephalosporins, and other ?-lactams. Despite the increasingly reported drug resistance, trimethoprim-sulfamethoxazole is still the drug of choice. However, the organism is still susceptible to ticarcillin-clavulanic acid, tigecycline, fluoroquinolones, polymyxin-B, and rifampicin. Genetic factors play a significant role not only in evolution of drug resistance but also in virulence of the organism. The outcome of patients having S. maltophilia infections can be improved by: using various combinations of novel therapeutic agents and aerosolized aminoglycosides or colistin, prompt administration of in vitro active antibiotics, removal of possible sources of infection such as infected indwelling intravascular catheters, and application of strict infection control measures. PMID:25202682

Al-Anazi, Khalid Ahmed; Al-Jasser, Asma M.

2014-01-01

37

A Highly Thermostable Xylanase from Stenotrophomonas maltophilia: Purification and Partial Characterization  

PubMed Central

Seven xylanolytic bacterial strains were isolated from saw-dust dump soil. The bacterial strain X6 was selected on the basis of the highest xylanase activity with no cellulase contamination. It was identified as Stenotrophomonas maltophilia by biochemical tests and 16S rRNA gene sequencing approach. Xylanase production studies by S. maltophilia on different commercial xylans and agro-industrial residues suggested that wheat bran was the best carbon source for xylanase production (26.4 0.6?IU/mL). The studies with inorganic and organic nitrogen sources suggested yeast extract as the best support for xylanase production (25 0.6?IU/mL). Maximum xylanase production was observed at initial medium pH = 8.0 (23.8 0.4?IU/mL) with production at pH = 7.0 and pH = 9.0 being almost comparable. Xylanase produced by S. maltophilia was purified to homogeneity using ammonium sulfate precipitation, gel filtration, and ion exchange chromatography. The final purification was 5.43-fold with recovery of 19.18%. The molecular weight of the purified xylanase protein was ~142?kDa. Both crude and purified xylanase had good stability at pH = 9.0 and 80C with activity retention greater than 90% after 30?min incubation. The enzyme stability at high temperature and alkaline pH make it potentially effective for industrial applications. PMID:24416589

Kumar, Sharad; Singh, Sudheer Kumar

2013-01-01

38

Genotyping of Environmental and Clinical Stenotrophomonas maltophilia Isolates and their Pathogenic Potential  

PubMed Central

Stenotrophomonas maltophilia is a highly versatile species with useful biotechnological potential but also with pathogenic properties. In light of possible differences in virulence characteristics, knowledge about genomic subgroups is therefore desirable. Two different genotyping methods, rep-PCR fingerprinting and partial gyrB gene sequencing were used to elucidate S. maltophilia intraspecies diversity. Rep-PCR fingerprinting revealed the presence of 12 large subgroups, while gyrB gene sequencing distinguished 10 subgroups. For 8 of them, the same strain composition was shown with both typing methods. A subset of 59 isolates representative for the gyrB groups was further investigated with regards to their pathogenic properties in a virulence model using Dictyostelium discoideum and Acanthamoeba castellanii as host organisms. A clear tendency towards accumulation of virulent strains could be observed for one group with A. castellanii and for two groups with D. discoideum. Several virulent strains did not cluster in any of the genetic groups, while other groups displayed no virulence properties at all. The amoeba pathogenicity model proved suitable in showing differences in S. maltophilia virulence. However, the model is still not sufficient to completely elucidate virulence as critical for a human host, since several strains involved in human infections did not show any virulence against amoeba. PMID:22110692

Adamek, Martina; Overhage, Jrg; Bathe, Stephan; Winter, Josef; Fischer, Reinhard; Schwartz, Thomas

2011-01-01

39

Dipeptidyl Aminopeptidase IV from Stenotrophomonas maltophilia Exhibits Activity against a Substrate Containing a 4-Hydroxyproline Residue?  

PubMed Central

The crystal structure of dipeptidyl aminopeptidase IV from Stenotrophomonas maltophilia was determined at 2.8- resolution by the multiple isomorphous replacement method, using platinum and selenomethionine derivatives. The crystals belong to space group P43212, with unit cell parameters a = b = 105.9 and c = 161.9 . Dipeptidyl aminopeptidase IV is a homodimer, and the subunit structure is composed of two domains, namely, N-terminal ?-propeller and C-terminal catalytic domains. At the active site, a hydrophobic pocket to accommodate a proline residue of the substrate is conserved as well as those of mammalian enzymes. Stenotrophomonas dipeptidyl aminopeptidase IV exhibited activity toward a substrate containing a 4-hydroxyproline residue at the second position from the N terminus. In the Stenotrophomonas enzyme, one of the residues composing the hydrophobic pocket at the active site is changed to Asn611 from the corresponding residue of Tyr631 in the porcine enzyme, which showed very low activity against the substrate containing 4-hydroxyproline. The N611Y mutant enzyme was generated by site-directed mutagenesis. The activity of this mutant enzyme toward a substrate containing 4-hydroxyproline decreased to 30.6% of that of the wild-type enzyme. Accordingly, it was considered that Asn611 would be one of the major factors involved in the recognition of substrates containing 4-hydroxyproline. PMID:18820015

Nakajima, Yoshitaka; Ito, Kiyoshi; Toshima, Tsubasa; Egawa, Takashi; Zheng, Heng; Oyama, Hiroshi; Wu, Yu-Fan; Takahashi, Eiji; Kyono, Kiyoshi; Yoshimoto, Tadashi

2008-01-01

40

Spectroscopic identification of AZT derivative obtained from biotransformation of AZT by Stenotrophomonas maltophilia  

NASA Astrophysics Data System (ADS)

The 3'-azido-2',3'-dideoxy-?-ribosylthymine (AZT, Zidovudine) is a cytostatic antivirial drug worldwide used in AIDS treatment or, in combination with other antiproliferative drugs, in treatment of cancer. About 30-40% of AZT is metabolised by conjunction with glucuronic acid in liver and about 70% is eliminated untouched by urinary system. In this work a possible fate of the AZT in the environment is studied. To this end, a product of AZT biotransformation by an environmental strain, Stenotrophomonas maltophilia, (aerobic, Gram(-) rod, common in soil and water) is found and isolated by HPLC and TLC techniques and identified by NMR and mass spectroscopy. All the molecular spectroscopy methods confirm presence of the product, which is AZT molecule hydroxylated in the position 2' of the deoxyribose ring.

Kruszewska, Hanna; Chmielowiec, Urszula; Bednarek, El?bieta; Witowska-Jarosz, Janina; Dobrowolski, Jan Cz.; Misicka, Aleksandra

2003-06-01

41

Stenotrophomonas maltophilia with histopathological features mimicking cutaneous gamma/delta T-cell lymphoma.  

PubMed

We report a case of cutaneous Stenotrophomonas maltophilia infection which presented with clinical and histopathological findings that mimicked a gamma/delta (??) T-cell lymphoma. In this case, tissue culture of the biopsy specimen was key to determining the diagnosis and allowing appropriate treatment with oral trimethoprim-sulfamethoxazole and topical silvadene. A prompt complete resolution of lesions was observed following antibiotic treatment, with no recurrence of disease over the last 5 years, supporting an infectious rather than malignant etiology. In our patient, radiation therapy was indicated based on the misdiagnosis of ?? T-cell lymphoma, which was supported both clinically and histopathologically. However, tissue culture in this case avoided unnecessary radiation exposure and highlights the role of tissue culture in the evaluation of the biopsy of an undiagnosed cutaneous lesion. PMID:25462188

Kash, Natalie; Vin, Harina; Danialan, Richard; Prieto, Victor G; Duvic, Madeleine

2015-01-01

42

Draft Genome Sequence of Stenotrophomonas maltophilia Strain B418, a Promising Agent for Biocontrol of Plant Pathogens and Root-Knot Nematode.  

PubMed

Stenotrophomonas maltophilia strain B418 was isolated from a barley rhizosphere in China. This bacterium exhibits broad-spectrum inhibitory activities against plant pathogens and root-knot nematode along with growth-promoting effects. Here, we present the draft genome sequence of S.maltophilia B418. PMID:25700397

Wu, Yuanzheng; Wang, Yilian; Li, Jishun; Hu, Jindong; Chen, Kai; Wei, Yanli; Bazhanov, Dmitry P; Bazhanova, Alesia A; Yang, Hetong

2015-01-01

43

In vitro efficacy of high-dose tobramycin against Burkholderia cepacia complex and Stenotrophomonas maltophilia isolates from cystic fibrosis patients.  

PubMed

Burkholderia cepacia complex and Stenotrophomonas maltophilia infections are associated with poor clinical outcomes in persons with cystic fibrosis (CF). The MIC50 based on planktonic growth and the biofilm concentration at which 50% of the isolates tested are inhibited (BIC50) of tobramycin were measured for 180 B. cepacia complex and 101 S. maltophilia CF isolates and were 100 ?g/ml for both species. New inhalation devices that deliver high tobramycin levels to the lung may be able to exceed these MICs. PMID:25348526

Ratjen, Anina; Yau, Yvonne; Wettlaufer, Jillian; Matukas, Larissa; Zlosnik, James E A; Speert, David P; LiPuma, John J; Tullis, Elizabeth; Waters, Valerie

2015-01-01

44

A Polysaccharide Lyase from Stenotrophomonas maltophilia with a Unique, pH-regulated Substrate Specificity*  

PubMed Central

Polysaccharide lyases (PLs) catalyze the depolymerization of anionic polysaccharides via a ?-elimination mechanism. PLs also play important roles in microbial pathogenesis, participating in bacterial invasion and toxin spread into the host tissue via degradation of the host extracellular matrix, or in microbial biofilm formation often associated with enhanced drug resistance. Stenotrophomonas maltophilia is a Gram-negative bacterium that is among the emerging multidrug-resistant organisms associated with chronic lung infections as well as with cystic fibrosis patients. A putative alginate lyase (Smlt1473) from S. maltophilia was heterologously expressed in Escherichia coli, purified in a one-step fashion via affinity chromatography, and activity as well as specificity determined for a range of polysaccharides. Interestingly, Smlt1473 catalyzed the degradation of not only alginate, but poly-?-d-glucuronic acid and hyaluronic acid as well. Furthermore, the pH optimum for enzymatic activity is substrate-dependent, with optimal hyaluronic acid degradation at pH 5, poly-?-d-glucuronic acid degradation at pH 7, and alginate degradation at pH 9. Analysis of the degradation products revealed that each substrate was cleaved endolytically into oligomers comprised predominantly of even numbers of sugar groups, with lower accumulation of trimers and pentamers. Collectively, these results imply that Smlt1473 is a multifunctional PL that exhibits broad substrate specificity, but utilizes pH as a mechanism to achieve selectivity. PMID:24257754

MacDonald, Logan C.; Berger, Bryan W.

2014-01-01

45

Modulation of FAD-dependent monooxygenase activity from aromatic compounds-degrading Stenotrophomonas maltophilia strain KB2.  

PubMed

The purpose of this study was purification and characterization of phenol monooxygenase from Stenotrophomonas maltophilia strain KB2, enzyme that catabolises phenol and its derivatives through the initial hydroxylation to catechols. The enzyme requires NADH and FAD as a cofactors for activity, catalyses hydroxylation of a wide range of monocyclic phenols, aromatic acids and dihydroxylated derivatives of benzene except for catechol. High activity of this monooxygenase was observed in cell extract of strain KB2 grown on phenol, 2-methylphenol, 3-metylphenol or 4-methylphenol. Ionic surfactants as well as cytochrome P450 inhibitors or 1,4-dioxane, acetone and n-butyl acetate inhibited the enzyme activity, while non-ionic surfactants, chloroethane, ethylbenzene, ethyl acetate, cyclohexane, and benzene enhanced it. These results indicate that the phenol monooxygenase from Stenotrophomonas maltophilia strain KB2 holds great potential for bioremediation. PMID:21927719

Wojcieszy?ska, Danuta; Gre?, Izabela; Hupert-Kocurek, Katarzyna; Guzik, Urszula

2011-01-01

46

Antibiogram of Stenotrophomonas maltophilia Isolated From Nkonkobe Municipality, Eastern Cape Province, South Africa  

PubMed Central

Background: Assessment of resistance genes is imperative, as they become disseminated to bacterial flora in plants and to the indigenous bacterial community, and thus ultimately contributes to the clinical problems of antibiotic resistant pathogens. Objectives: The research was to assess the antibiotic characteristics and incidence of sul3 genes of Stenotrophomonas maltophilia isolates recovered from rhizospheres plant in Nkonkobe Municipality. Materials and Methods: Identification and assessment of resistance genes (sul2 and sul3 genes) were carried out using polymerase chain reaction (PCR). Analytical profile index (API) was used for biochemical characterization for identification before the PCR. Antibiotic susceptibility test was carried out using the approved guidelines and standards of Clinical Laboratory Standard Institute (CLSI). Results: A total of 125 isolates were identified, composed of 120 (96%) from grass root rhizosphere and 5 (4%) from soil butternut root rhizosphere. In vitro antibiotic susceptibility tests showed varying resistances to meropenem (8.9%), cefuroxime (95.6 %), ampicillin-sulbactam (53.9%), ceftazidime (10.7%), cefepime (29.3 %), minocycline (2.2%), kanamycin (56.9%), ofloxacin (2.9%), levofloxacin (1.3%), moxifloxacin (2.8%), ciprofloxacin (24.3%), gatifloxacin (1.3%), polymyxin B (2.9 %), cotrimoxazole (26.1%), trimethoprim (98.6%) and aztreonam (58%). The isolates were susceptible to the fluoroquinolones (74.3-94.7%), polymycin (97.1%) and meropenem (88.1%). The newest sulphonamide resistance gene, sul3, was detected among the trimethoprim-sulfamethoxazole (cotrimoxazole)-resistant isolates, while the most frequent sulphonamide-resistant gene in animal source isolates, sul2, was not. Conclusions: The commensal S. maltophilia isolates in the Nkonkobe Municipality environment harbored the resistant gene sul3 as clinical counterparts, especially from the perspective of reservoirs of antibiotic resistance determinants. PMID:25789125

Adegoke, Anthony Ayodeji; Okoh, Anthony I.

2014-01-01

47

Aflatoxin B(1) degradation by Stenotrophomonas maltophilia and other microbes selected using coumarin medium.  

PubMed

Aflatoxin B(1) (AFB(1)) is one of the most harmful mycotoxins in animal production and food industry. A safe, effective and environmentally sound detoxification method is needed for controlling this toxin. In this study, 65 samples were screened from various sources with vast microbial populations using a newly developed medium containing coumarin as the sole carbon source. Twenty five single-colony bacterial isolates showing AFB(1) reduction activity in a liquid culture medium were selected from the screen. Isolate 35-3, obtained from tapir feces and identified to be Stenotrophomonas maltophilia, reduced AFB(1) by 82.5% after incubation in the liquid medium at 37 degrees C for 72 h. The culture supernatant of isolate 35-3 was able to degrade AFB(1) effectively, whereas the viable cells and cell extracts were far less effective. Factors influencing AFB(1) degradation by the culture supernatant were investigated. Activity was reduced to 60.8% and 63.5% at 20 degrees C and 30 degrees C, respectively, from 78.7% at 37 degrees C. The highest degradation rate was 84.8% at pH 8 and the lowest was only 14.3% at pH 4.0. Ions Mg(2+) and Cu(2+) were activators for AFB(1) degradation, however ion Zn(2+) was a strong inhibitor. Treatments with proteinase K, proteinase K plus SDS and heating significantly reduced or eradicated the degradation activity of the culture supernatant. The results indicated that the degradation of AFB(1) by S. maltophilia 35-3 was enzymatic and could have a great potential in industrial applications. PMID:19325817

Guan, Shu; Ji, Cheng; Zhou, Ting; Li, Junxia; Ma, Qiugang; Niu, Tiangui

2008-08-01

48

A Stenotrophomonas maltophilia Multilocus Sequence Typing Scheme for Inferring Population Structure?  

PubMed Central

Stenotrophomonas maltophilia is an opportunistic, highly resistant, and ubiquitous pathogen. Strains have been assigned to genogroups using amplified fragment length polymorphism. Hence, isolates of environmental and clinical origin predominate in different groups. A multilocus sequence typing (MLST) scheme was developed using a highly diverse selection of 70 strains of various ecological origins from seven countries on all continents including strains of the 10 previously defined genogroups. Sequence data were assigned to 54 sequence types (ST) based on seven loci. Indices of association for all isolates and clinical isolates of 2.498 and 2.562 indicated a significant linkage disequilibrium, as well as high congruence of tree topologies from different loci. Potential recombination events were detected in one-sixth of all ST. Calculation of the mean divergence between and within predicted clusters confirmed previously defined groups and revealed five additional groups. Consideration of the different ecological origins showed that 18 out of 31 respiratory tract isolates, including 12 out of 19 isolates from cystic fibrosis (CF) patients, belonged to genogroup 6. In contrast, 16 invasive strains isolated from blood cultures were distributed among nine different genogroups. Three genogroups contained isolates of strictly environmental origin that also featured high sequence distances to other genogroups, including the S. maltophilia type strain. On the basis of this MLST scheme, isolates can be assigned to the genogroups of this species in order to further scrutinize the population structure of this species and to unravel the uneven distribution of environmental and clinical isolates obtained from infected, colonized, or CF patients. PMID:19251858

Kaiser, Sabine; Biehler, Klaus; Jonas, Daniel

2009-01-01

49

The Impact of spgM, rpfF, rmlA Gene Distribution on Biofilm Formation in Stenotrophomonas maltophilia  

PubMed Central

Background Stenotrophomonas maltophilia is emerging as one of the most frequently found bacteria in chronic pulmonary infection. Biofilm is increasingly recognized as a contributing factor to disease pathogenesis. In the present study, a total of 37 isolates of S. maltophilia obtained from chronic pulmonary infection patients were evaluated to the relationship between biofilm production and the relative genes expression. Methods The clonal relatedness of isolates was determined by pulse-field gel electrophoresis. Biofilm formation assays were performed by crystal violet assay, and confirmed by Electron microscopy analysis and CLSM analysis. PCR was employed to learn gene distribution and expression. Results Twenty-four pulsotypes were designated for 37 S. maltophilia isolates, and these 24 pulsotypes exhibited various levels of biofilm production, 8 strong biofilm-producing S. maltophilia strains with OD492 value above 0.6, 14 middle biofilm-producing strains with OD492 average value of 0.4 and 2 weak biofilm-producing strains with OD492 average value of 0.19. CLSM analysis showed that the isolates from the early stage of chronic infection enable to form more highly structured and multilayered biofim than those in the late stage. The prevalence of spgM, rmlA, and rpfF genes was 83.3%, 87.5%, and 50.0% in 24 S. maltophilia strains, respectively, and the presence of rmlA, spgM or rpfF had a close relationship with biofilm formation but did not significantly affect the mean amount of biofilm. Significant mutations of spgM and rmlA were found in both strong and weak biofilm-producing strains. Conclusion Mutations in spgM and rmlA may be relevant to biofilm formation in the clinical isolates of S. maltophilia. PMID:25285537

Zhuo, Chao; Zhao, Qian-yu; Xiao, Shu-nian

2014-01-01

50

The complete genome, comparative and functional analysis of Stenotrophomonas maltophilia reveals an organism heavily shielded by drug resistance determinants  

PubMed Central

Background Stenotrophomonas maltophilia is a nosocomial opportunistic pathogen of the Xanthomonadaceae. The organism has been isolated from both clinical and soil environments in addition to the sputum of cystic fibrosis patients and the immunocompromised. Whilst relatively distant phylogenetically, the closest sequenced relatives of S. maltophilia are the plant pathogenic xanthomonads. Results The genome of the bacteremia-associated isolate S. maltophilia K279a is 4,851,126 bp and of high G+C content. The sequence reveals an organism with a remarkable capacity for drug and heavy metal resistance. In addition to a number of genes conferring resistance to antimicrobial drugs of different classes via alternative mechanisms, nine resistance-nodulation-division (RND)-type putative antimicrobial efflux systems are present. Functional genomic analysis confirms a role in drug resistance for several of the novel RND efflux pumps. S. maltophilia possesses potentially mobile regions of DNA and encodes a number of pili and fimbriae likely to be involved in adhesion and biofilm formation that may also contribute to increased antimicrobial drug resistance. Conclusion The panoply of antimicrobial drug resistance genes and mobile genetic elements found suggests that the organism can act as a reservoir of antimicrobial drug resistance determinants in a clinical environment, which is an issue of considerable concern. PMID:18419807

Crossman, Lisa C; Gould, Virginia C; Dow, J Maxwell; Vernikos, Georgios S; Okazaki, Aki; Sebaihia, Mohammed; Saunders, David; Arrowsmith, Claire; Carver, Tim; Peters, Nicholas; Adlem, Ellen; Kerhornou, Arnaud; Lord, Angela; Murphy, Lee; Seeger, Katharine; Squares, Robert; Rutter, Simon; Quail, Michael A; Rajandream, Mari-Adele; Harris, David; Churcher, Carol; Bentley, Stephen D; Parkhill, Julian; Thomson, Nicholas R; Avison, Matthew B

2008-01-01

51

Cloning and characterization of SmeT, a repressor of the Stenotrophomonas maltophilia multidrug efflux pump SmeDEF.  

PubMed

We report on the cloning of the gene smeT, which encodes the transcriptional regulator of the Stenotrophomonas maltophilia efflux pump SmeDEF. SmeT belongs to the TetR and AcrR family of transcriptional regulators. The smeT gene is located upstream from the structural operon of the pump genes smeDEF and is divergently transcribed from those genes. Experiments with S. maltophilia and the heterologous host Escherichia coli have demonstrated that SmeT is a transcriptional repressor. S1 nuclease mapping has demonstrated that expression of smeT is driven by a single promoter lying close to the 5' end of the gene and that expression of smeDEF is driven by an unique promoter that overlaps with promoter PSMET: The level of expression of smeT is higher in smeDEF-overproducing S. maltophilia strain D457R, which suggests that SmeT represses its own expression. Band-shifting assays have shown that wild-type strain S. maltophilia D457 contains a cellular factor(s) capable of binding to the intergenic smeT-smeD region. That cellular factor(s) was absent from smeDEF-overproducing S. maltophilia strain D457R. The sequence of smeT from D457R showed a point mutation that led to a Leu166Gln change within the SmeT protein. This change allowed overexpression of both smeDEF and smeT in D457R. It was noteworthy that expression of wild-type SmeT did not fully complement the smeT mutation in D457R. This suggests that the wild-type protein is not dominant over the mutant SmeT. PMID:12384340

Snchez, Patricia; Alonso, Ana; Martinez, Jose L

2002-11-01

52

Stenotrophomonas maltophilia Virulence and Specific Variations in Trace Elements during Acute Lung Infection: Implications in Cystic Fibrosis  

PubMed Central

Metal ions are necessary for the proper functioning of the immune system, and, therefore, they might have a significant influence on the interaction between bacteria and host. Ionic dyshomeostasis has been recently observed also in cystic fibrosis (CF) patients, whose respiratory tract is frequently colonized by Stenotrophomonas maltophilia. For the first time, here we used an inductively mass spectrometry method to perform a spatial and temporal analysis of the pattern of changes in a broad range of major trace elements in response to pulmonary infection by S. maltophilia. To this, DBA/2 mouse lungs were comparatively infected by a CF strain and by an environmental one. Our results showed that pulmonary ionomic profile was significantly affected during infection. Infected mice showed increased lung levels of Mg, P, S, K, Zn, Se, and Rb. To the contrary, Mn, Fe, Co, and Cu levels resulted significantly decreased. Changes of element concentrations were correlated with pulmonary bacterial load and markers of inflammation, and occurred mostly on day 3 post-exposure, when severity of infection culminated. Interestingly, CF strain significantly more virulent than the environmental one in our murine model - provoked a more significant impact in perturbing pulmonary metal homeostasis. Particularly, exposure to CF strain exclusively increased P and K levels, while decreased Fe and Mn ones. Overall, our data clearly indicate that S. maltophilia modulates pulmonary metal balance in a concerted and virulence-dependent manner highlighting the potential role of the element dyshomeostasis during the progression of S. maltophilia infection, probably exacerbating the harmful effects of the loss of CF transmembrane conductance regulator function. Further investigations are required to understand the biological significance of these alterations and to confirm they are specifically caused by S. maltophilia. PMID:24586389

Crocetta, Valentina; Consalvo, Ada; Zappacosta, Roberta; Di Ilio, Carmine; Di Bonaventura, Giovanni

2014-01-01

53

Prevalence and detection of Stenotrophomonas maltophilia carrying metallo-?-lactamase blaL1 in Beijing, China  

PubMed Central

Intrinsic ?-lactam resistance in Stenotrophomonas maltophilia is caused by blaL1 and/or blaL2, a kind of metallo-?-lactamase with a broad substrate spectrum including carbapenems. A rapid and sensitive molecular method for the detection of blaL1 in clinical samples is needed to guide therapeutic treatment. In present study, we first described a loop-mediated isothermal amplification (LAMP) method for the rapid detection of blaL1 in clinical samples by using two methods including a chromogenic method using calcein/Mn2+ complex and the real-time turbidity monitoring to assess the reaction. Then dissemination of L1-producing S. maltophilia was investigated from ICU patients in three top hospital in Beijing, China. The results showed that both methods detected the target DNA within 60 min under isothermal conditions (65C). The detection limit of LAMP was 3.79 pg/?l DNA, and its sensitivity 100-fold greater than that of conventional PCR. All 21 test strains except for S. maltophilia were negative for blaL1, indicative of the high-specificity of the primers for the blaL1. A total of 22 L1-positive isolates were identified for LAMP-based surveillance of blaL1 from 105 ICU patients with clinically suspected multi-resistant infections. The sequences of these blaL1 genes were conservative with only a few sites mutated, and the strains had highly resistant to ?-lactam antibiotics. The MLST recovered that 22 strains belonged to seven different S. maltophilia sequence types (STs). Furthermore, co-occurrence of blaL1 and blaL2 genes were detected in all of isolates. Strikingly, S. maltophilia DCPS-01 was recovered to contain blaL1, blaL2, and blaNDM-1 genes, possessing an ability to hydrolyse all ?-lactams antibiotics. Our data showed the diversity types of S. maltophilia carrying blaL1 and co-occurrence of many resistant genes in the clinical strains signal an ongoing and fast evolution of S. maltophilia resulting from their wide spread in the respiratory infections, and therefore will be difficult to control. PMID:25538701

Yang, Zhan; Liu, Wei; Cui, Qian; Niu, Wenkai; Li, Huan; Zhao, Xiangna; Wei, Xiao; Wang, Xuesong; Huang, Simo; Dong, Derong; Lu, Sijing; Bai, Changqing; Li, Yan; Huang, Liuyu; Yuan, Jing

2014-01-01

54

Friends or foes: can we make a distinction between beneficial and harmful strains of the Stenotrophomonas maltophilia complex?  

PubMed Central

Stenotrophomonas maltophilia is an emerging multi-drug-resistant global opportunistic pathogen of environmental, mainly plant-associated origin. It is also used as a biocontrol or stress protecting agent for crops in sustainable agricultural as well as in bioremediation strategies. In order to establish effective protocols to distinguish harmless from harmful strains, our discussion must take into consideration the current data available surrounding the ecology, evolution and pathogenicity of the species complex. The mutation rate was identified as one of several possible criteria for strain plasticity, but it is currently impossible to distinguish beneficial from harmful S. maltophilia strains. This may compromise the possibility of the release and application for environmental biotechnology of this bacterial species. The close relative S. rhizophila, which can be clearly differentiated from S. maltophilia, provides a harmless alternative for biotechnological applications without human health risks. This is mainly because it is unable to growth at the human body temperature, 37?C due to the absence of heat shock genes and a potentially temperature-regulated suicide mechanism. PMID:25873912

Berg, Gabriele; Martinez, Jose L.

2015-01-01

55

A Function of SmeDEF, the Major Quinolone Resistance Determinant of Stenotrophomonas maltophilia, Is the Colonization of Plant Roots  

PubMed Central

Quinolones are synthetic antibiotics, and the main cause of resistance to these antimicrobials is mutation of the genes encoding their targets. However, in contrast to the case for other organisms, such mutations have not been found in quinolone-resistant Stenotrophomonas maltophilia isolates, in which overproduction of the SmeDEF efflux pump is a major cause of quinolone resistance. SmeDEF is chromosomally encoded and highly conserved in all studied S. maltophilia strains; it is an ancient element that evolved over millions of years in this species. It thus seems unlikely that its main function would be resistance to quinolones, a family of synthetic antibiotics not present in natural environments until the last few decades. Expression of SmeDEF is tightly controlled by the transcriptional repressor SmeT. Our work shows that plant-produced flavonoids can bind to SmeT, releasing it from smeDEF and smeT operators. Antibiotics extruded by SmeDEF do not impede the binding of SmeT to DNA. The fact that plant-produced flavonoids specifically induce smeDEF expression indicates that they are bona fide effectors regulating expression of this resistance determinant. Expression of efflux pumps is usually downregulated unless their activity is needed. Since smeDEF expression is triggered by plant-produced flavonoids, we reasoned that this efflux pump may have a role in the colonization of plants by S. maltophilia. Our results showed that, indeed, deletion of smeE impairs S. maltophilia colonization of plant roots. Altogether, our results indicate that quinolone resistance is a recent function of SmeDEF and that colonization of plant roots is likely one original function of this efflux pump. PMID:24837376

Garca-Len, Guillermo; Hernndez, Alvaro; Hernando-Amado, Sara; Alavi, Peyman; Berg, Gabriele

2014-01-01

56

Introducing a salt bridge into the lipase of Stenotrophomonas maltophilia results in a very large increase in thermal stability.  

PubMed

High thermostability of enzymes is a prerequisite for their biotechnological applications. An organic solvent-tolerant and cold-active lipase, from the Stenotrophomonas maltophilia, was unstable above 40 C in previous studies. To increase the enzyme stability, possible hydrogen-bond networks were simulated by the introduction of a salt bridge in a highly flexible region of the protein. Compared with the wild-type lipase, a mutant lipase (G165D and F73R) showed a >900-fold improvement in half-life at 50 C, with the optimal activity-temperature increasing from 35 to 90 C. Therefore, the hydrogen-bond strategy is a powerful approach for improving enzyme stability through the introduction of a salt bridge. PMID:25257598

Wu, Jian-Ping; Li, Mu; Zhou, Yong; Yang, Li-Rong; Xu, Gang

2015-02-01

57

Degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by Stenotrophomonas maltophilia PB1.  

PubMed Central

A mixed microbial culture capable of metabolizing the explosive RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) was obtained from soil enrichments under aerobic and nitrogen-limiting conditions. A bacterium, Stenotrophomonas maltophilia PB1, isolated from the culture used RDX as a sole source of nitrogen for growth. Three moles of nitrogen was used per mole of RDX, yielding a metabolite identified by mass spectroscopy and 1H nuclear magnetic resonance analysis as methylene-N-(hydroxymethyl)-hydroxylamine-N'-(hydroxymethyl)nitroamin e. The bacterium also used s-triazine as a sole source of nitrogen but not the structurally similar compounds octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, cyanuric acid, and melamine. An inducible RDX-degrading activity was present in crude cell extracts. PMID:7747953

Binks, P R; Nicklin, S; Bruce, N C

1995-01-01

58

Purification and characterization of novel organic solvent tolerant 98kDa alkaline protease from isolated Stenotrophomonas maltophilia strain SK.  

PubMed

Ability of microorganisms to grow at alkaline pH makes them an attractive target for several industrial applications. Thus, search for new extremozyme producing microorganisms must be a continuous exercise. Hence, we isolated a potent alkaline protease producing bacteria from slaughter house soil. The morphological, biochemical and 16S rDNA gene sequencing studies revealed that the isolated bacteria is Stenotrophomonas maltophilia strain SK. Alkaline protease from S. maltophilia strain SK was purified by using ammonium sulphate precipitation and DEAE-cellulose ion exchange column chromatography. The purified enzyme was optimally active at pH 9.0 and temperature 40C with broad substrate specificity. It was observed that the metal ions such as Ca(++), Mg(++) and Fe(+++) completely repressed the enzyme activity. The enzyme was stable in presence of various water miscible solvents like ethanol, methanol, isopropanol at 25% (v/v) concentration and less stable at 37.5% (v/v) concentration. These robust properties of enzyme might be applicable for various applications in detergent and pharmaceutical industries. PMID:25462807

Waghmare, Shailesh R; Gurav, Aparna A; Mali, Sonal A; Nadaf, Naiem H; Jadhav, Deepak B; Sonawane, Kailas D

2015-03-01

59

Synergistic Activities of Macrolide Antibiotics against Pseudomonas aeruginosa, Burkholderia cepacia, Stenotrophomonas maltophilia, and Alcaligenes xylosoxidans Isolated from Patients with Cystic Fibrosis  

Microsoft Academic Search

Azithromycin and clarithromycin were paired with other antibiotics to test synergistic activity against 300 multidrug-resistant pathogens isolated from cystic fibrosis (CF) patients. Clarithromycin-tobramycin was most active against Pseudomonas aeruginosa and inhibited 58% of strains. Azithromycin-trimethoprim-sulfa- methoxazole, azithromycin-ceftazidime, and azithromycin-doxycycline or azithromycin-trimethoprim-sulfame- thoxazole inhibited 40, 20, and 22% of Stenotrophomonas maltophilia, Burkholderia cepacia complex, and Ach- romobacter (Alcaligenes) xylosoxidans strains, respectively.

Lisa Saiman; Yunhua Chen; Pablo San Gabriel; Charles Knirsch

2002-01-01

60

Genome-Wide Identification of Genes Necessary for Biofilm Formation of Nosocomial Pathogen Stenotrophomonas maltophilia Reveals Orphan Response Regulator FsnR is a Critical Modulator.  

PubMed

Stenotrophomonas maltophilia is a gram-negative, bacterial pathogen of increasing concern to human health. Most clinical isolates of S. maltophilia efficiently form biofilms on biotic and abiotic surfaces, making this bacterium resistant to a number of antibiotic treatments and hard to be eliminated. To date, very few studies have investigated the molecular and regulatory mechanisms responsible for S. maltophilia biofilm formation. Here we constructed a random transposon insertion mutant library of S. maltophilia ATCC 13637 and screened 14,028 clones. A total of 46 non-redundant genes were identified. Mutants of these genes exhibited marked changes in biofilm formation; suggesting multiple physiological pathways, including extracellular polysaccharide production, purine synthesis, transportation, peptide and lipid synthesis, were involved in bacterial cell aggregation. Of these genes, 20 putatively contributed to flagella biosynthesis, indicating a critical role for cell motility in S. maltophilia biofilm formation. Genetic and biochemical evidence demonstrated an orphan response regulator, FsnR, activated transcription of at least two flagella-associated operons by directly binding to their promoters. The regulatory protein plays a fundamental role in controlling flagella assembly, cell motility and biofilm formation. These results provide a genetic basis to systematically study biofilm formation of S. maltophilia. PMID:25480754

Kang, Xiu-Min; Wang, Fang-Fang; Zhang, Huan; Zhang, Qi; Qian, Wei

2014-12-01

61

Identification and characterization of a serious multidrug resistant Stenotrophomonas maltophilia strain in China.  

PubMed

An S. maltophilia strain named WJ66 was isolated from a patient; WJ66 showed resistance to more antibiotics than the other S. maltophilia strains. This bacteraemia is resistant to sulphonamides, or fluoroquinolones, while the representative strain of S. maltophilia, K279a, is sensitive to both. To explore drug resistance determinants of this strain, the draft genome sequence of WJ66 was determined and compared to other S. maltophilia sequences. Genome sequencing and genome-wide evolutionary analysis revealed that WJ66 was highly homologous with the strain K279a, but strain WJ66 contained additional antibiotic resistance genes. Further analysis confirmed that strain WJ66 contained an amino acid substitution (Q83L) in fluoroquinolone target GyrA and carried a class 1 integron, with an aadA2 gene in the resistance gene cassette. Homology analysis from the pathogen-host interaction database showed that strain WJ66 lacks raxST and raxA, which is consistent with K279a. Comparative genomic analyses revealed that subtle nucleotide differences contribute to various significant phenotypes in close genetic relationship strains. PMID:25654114

Zhao, Yan; Niu, Wenkai; Sun, Yanxia; Hao, Huaijie; Yu, Dong; Xu, Guangyang; Shang, Xueyi; Tang, Xueping; Lu, Sijing; Yue, Junjie; Li, Yan

2015-01-01

62

Identification and Characterization of a Serious Multidrug Resistant Stenotrophomonas maltophilia Strain in China  

PubMed Central

An S. maltophilia strain named WJ66 was isolated from a patient; WJ66 showed resistance to more antibiotics than the other S. maltophilia strains. This bacteraemia is resistant to sulphonamides, or fluoroquinolones, while the representative strain of S. maltophilia, K279a, is sensitive to both. To explore drug resistance determinants of this strain, the draft genome sequence of WJ66 was determined and compared to other S. maltophilia sequences. Genome sequencing and genome-wide evolutionary analysis revealed that WJ66 was highly homologous with the strain K279a, but strain WJ66 contained additional antibiotic resistance genes. Further analysis confirmed that strain WJ66 contained an amino acid substitution (Q83L) in fluoroquinolone target GyrA and carried a class 1 integron, with an aadA2 gene in the resistance gene cassette. Homology analysis from the pathogen-host interaction database showed that strain WJ66 lacks raxST and raxA, which is consistent with K279a. Comparative genomic analyses revealed that subtle nucleotide differences contribute to various significant phenotypes in close genetic relationship strains. PMID:25654114

Zhao, Yan; Niu, Wenkai; Sun, Yanxia; Hao, Huaijie; Yu, Dong; Xu, Guangyang; Shang, Xueyi; Tang, Xueping; Lu, Sijing; Li, Yan

2015-01-01

63

A Linkage between SmeIJK Efflux Pump, Cell Envelope Integrity, and ?E-Mediated Envelope Stress Response in Stenotrophomonas maltophilia  

PubMed Central

Resistance nodulation division (RND) efflux pumps, such as the SmeIJK pump of Stenotrophomonas maltophilia, are known to contribute to the multidrug resistance in Gram-negative bacteria. However, some RND pumps are constitutively expressed even though no antimicrobial stresses occur, implying that there should be some physical implications for these RND pumps. In this study, the role of SmeIJK in antimicrobials resistance, envelope integrity, and ?E-mediated envelope stress response (ESR) of S. maltophilia was assessed. SmeIJK was involved in the intrinsic resistance of S. maltophilia KJ to aminoglycosides and leucomycin. Compared with the wild-type KJ, the smeIJK deletion mutant exhibited growth retardation in the MH medium, an increased sensitivity to membrane-damaging agents (MDAs), as well as activation of an ?E-mediated ESR. Moreover, the expression of smeIJK was further induced by sub-lethal concentrations of MDAs or surfactants in an ?E-dependent manner. These data collectively suggested an alternative physiological role of smeIJK in cell envelope integrity maintenance and ?E-mediated ESR beyond the efflux of antibiotics. Because of the necessity of the physiological role of SmeIJK in protecting S. maltophilia from the envelope stress, smeIJK is constitutively expressed, which, in turn, contributes the intrinsic resistance to aminoglycoside and leucomycin. This is the first demonstration of the linkage among RND-type efflux pump, cell envelope integrity, and ?E-mediated ESR in S. maltophilia. PMID:25390933

Huang, Yi-Wei; Liou, Rung-Shiuan; Lin, Yi-Tsung; Huang, Hsin-Hui; Yang, Tsuey-Ching

2014-01-01

64

A linkage between SmeIJK efflux pump, cell envelope integrity, and ?E-mediated envelope stress response in Stenotrophomonas maltophilia.  

PubMed

Resistance nodulation division (RND) efflux pumps, such as the SmeIJK pump of Stenotrophomonas maltophilia, are known to contribute to the multidrug resistance in Gram-negative bacteria. However, some RND pumps are constitutively expressed even though no antimicrobial stresses occur, implying that there should be some physical implications for these RND pumps. In this study, the role of SmeIJK in antimicrobials resistance, envelope integrity, and ?E-mediated envelope stress response (ESR) of S. maltophilia was assessed. SmeIJK was involved in the intrinsic resistance of S. maltophilia KJ to aminoglycosides and leucomycin. Compared with the wild-type KJ, the smeIJK deletion mutant exhibited growth retardation in the MH medium, an increased sensitivity to membrane-damaging agents (MDAs), as well as activation of an ?E-mediated ESR. Moreover, the expression of smeIJK was further induced by sub-lethal concentrations of MDAs or surfactants in an ?E-dependent manner. These data collectively suggested an alternative physiological role of smeIJK in cell envelope integrity maintenance and ?E-mediated ESR beyond the efflux of antibiotics. Because of the necessity of the physiological role of SmeIJK in protecting S. maltophilia from the envelope stress, smeIJK is constitutively expressed, which, in turn, contributes the intrinsic resistance to aminoglycoside and leucomycin. This is the first demonstration of the linkage among RND-type efflux pump, cell envelope integrity, and ?E-mediated ESR in S. maltophilia. PMID:25390933

Huang, Yi-Wei; Liou, Rung-Shiuan; Lin, Yi-Tsung; Huang, Hsin-Hui; Yang, Tsuey-Ching

2014-01-01

65

Identification of a Novel 6?-N-Aminoglycoside Acetyltransferase, AAC(6?)-Iak, from a Multidrug-Resistant Clinical Isolate of Stenotrophomonas maltophilia  

PubMed Central

Stenotrophomonas maltophilia IOMTU250 has a novel 6?-N-aminoglycoside acetyltransferase-encoding gene, aac(6?)-Iak. The encoded protein, AAC(6?)-Iak, consists of 153 amino acids and has 86.3% identity to AAC(6?)-Iz. Escherichia coli transformed with a plasmid containing aac(6?)-Iak exhibited decreased susceptibility to arbekacin, dibekacin, neomycin, netilmicin, sisomicin, and tobramycin. Thin-layer chromatography showed that AAC(6?)-Iak acetylated amikacin, arbekacin, dibekacin, isepamicin, kanamycin, neomycin, netilmicin, sisomicin, and tobramycin but not apramycin, gentamicin, or lividomycin. PMID:25092711

Tada, Tatsuya; Miyoshi-Akiyama, Tohru; Dahal, Rajan K.; Mishra, Shyam K.; Shimada, Kayo; Ohara, Hiroshi; Pokhrel, Bharat M.

2014-01-01

66

Identification of a novel 6'-N-aminoglycoside acetyltransferase, AAC(6')-Iak, from a multidrug-resistant clinical isolate of Stenotrophomonas maltophilia.  

PubMed

Stenotrophomonas maltophilia IOMTU250 has a novel 6'-N-aminoglycoside acetyltransferase-encoding gene, aac(6')-Iak. The encoded protein, AAC(6')-Iak, consists of 153 amino acids and has 86.3% identity to AAC(6')-Iz. Escherichia coli transformed with a plasmid containing aac(6')-Iak exhibited decreased susceptibility to arbekacin, dibekacin, neomycin, netilmicin, sisomicin, and tobramycin. Thin-layer chromatography showed that AAC(6')-Iak acetylated amikacin, arbekacin, dibekacin, isepamicin, kanamycin, neomycin, netilmicin, sisomicin, and tobramycin but not apramycin, gentamicin, or lividomycin. PMID:25092711

Tada, Tatsuya; Miyoshi-Akiyama, Tohru; Dahal, Rajan K; Mishra, Shyam K; Shimada, Kayo; Ohara, Hiroshi; Kirikae, Teruo; Pokhrel, Bharat M

2014-10-01

67

Structural and Functional Analysis of SmeT, the Repressor of the Stenotrophomonas maltophilia Multidrug Efflux Pump SmeDEF*  

PubMed Central

Stenotrophomonas maltophilia is an opportunistic pathogen characterized for its intrinsic low susceptibility to several antibiotics. Part of this low susceptibility relies on the expression of chromosomally encoded multidrug efflux pumps, with SmeDEF being the most relevant antibiotic resistance efflux pump so far studied in this bacterial species. Expression of smeDEF is down-regulated by the SmeT repressor, encoded upstream smeDEF, in its complementary DNA strand. In the present article we present the crystal structure of SmeT and analyze its interactions with its cognate operator. Like other members of the TetR family of transcriptional repressors, SmeT behaves as a dimer and presents some common structural features with other TetR proteins like TtgR, QacR, and TetR. Differing from other TetR proteins for which the structure is available, SmeT turned out to have two extensions at the N and C termini that might be relevant for its function. Besides, SmeT presents the smallest binding pocket so far described in the TetR family of transcriptional repressors, which may correlate with a specific type and range of effectors. In vitro studies revealed that SmeT binds to a 28-bp pseudopalindromic region, forming two complexes. This operator region was found to overlap the promoters of smeT and smeDEF. This finding is consistent with a role for SmeT simultaneously down-regulating smeT and smeDEF transcription, likely by steric hindrance on RNA polymerase binding to DNA. PMID:19324881

Hernndez, Alvaro; Mat, Mara J.; Snchez-Daz, Patricia C.; Romero, Antonio; Rojo, Fernando; Martnez, Jos L.

2009-01-01

68

Antibacterial and Cytotoxic Efficacy of Extracellular Silver Nanoparticles Biofabricated from Chromium Reducing Novel OS4 Strain of Stenotrophomonas maltophilia  

PubMed Central

Biofabricated metal nanoparticles are generally biocompatible, inexpensive, and ecofriendly, therefore, are used preferably in industries, medical and material science research. Considering the importance of biofabricated materials, we isolated, characterized and identified a novel bacterial strain OS4 of Stenotrophomonas maltophilia (GenBank: JN247637.1). At neutral pH, this Gram negative bacterial strain significantly reduced hexavalent chromium, an important heavy metal contaminant found in the tannery effluents and minings. Subsequently, even at room temperature the supernatant of log phase grown culture of strain OS4 also reduced silver nitrate (AgNO3) to generate nanoparticles (AgNPs). These AgNPs were further characterized by UVvisible, Nanophox particle size analyzer, XRD, SEM and FTIR. As evident from the FTIR data, plausibly the protein components of supernatant caused the reduction of AgNO3. The cuboid and homogenous AgNPs showed a characteristic UV-visible peak at 428 nm with average size of ?93 nm. The XRD spectra exhibited the characteristic Bragg peaks of 111, 200, 220 and 311 facets of the face centred cubic symmetry of nanoparticles suggesting that these nanoparticles were crystalline in nature. From the nanoparticle release kinetics data, the rapid release of AgNPs was correlated with the particle size and increasing surface area of the nanoparticles. A highly significant antimicrobial activity against medically important bacteria by the biofabricated AgNPs was also revealed as decline in growth of Staphylococcus aureus (91%), Escherichia coli (69%) and Serratia marcescens (66%) substantially. Additionally, different cytotoxic assays showed no toxicity of AgNPs to liver function, RBCs, splenocytes and HeLa cells, hence these particles were safe to use. Therefore, this novel bacterial strain OS4 is likely to provide broad spectrum benefits for curing chromium polluted sites, for biofabrication of AgNPs and ultimately in the nanoparticle based drug formulation for the treatment of infectious diseases. PMID:23555625

Oves, Mohammad; Khan, Mohammad Saghir; Zaidi, Almas; Ahmed, Arham S.; Ahmed, Faheem; Ahmad, Ejaz; Sherwani, Asif; Owais, Mohammad; Azam, Ameer

2013-01-01

69

Stenotrophomonas maltophilia SeITE02, a New Bacterial Strain Suitable for Bioremediation of Selenite-Contaminated Environmental Matrices?  

PubMed Central

Biochemical and proteomic tools have been utilized for investigating the mechanism of action of a new Stenotrophomonas maltophilia strain (SeITE02), a gammaproteobacterium capable of resistance to high concentrations of selenite [SeO32?, Se(IV)], reducing it to nontoxic elemental selenium under aerobic conditions; this strain was previously isolated from a selenite-contaminated mining soil. Biochemical analysis demonstrated that (i) nitrite reductase does not seem to take part in the process of selenite reduction by the bacterial strain SeITE02, although its involvement in this process had been hypothesized in other cases; (ii) nitrite strongly interferes with selenite removal when the two oxyanions (NO2? and SeO32?) are simultaneously present, suggesting that the two reduction/detoxification pathways share a common enzymatic step, probably at the level of cellular transport; (iii) in vitro, selenite reduction does not take place in the membrane or periplasmic fractions but only in the cytoplasm, where maximum activity is exhibited at pH 6.0 in the presence of NADPH; and (iv) glutathione is involved in the selenite reduction mechanism, since inhibition of its synthesis leads to a considerable delay in the onset of reduction. As far as the proteomic findings are concerned, the evidence was reached that 0.2 mM selenite and 16 mM nitrite, when added to the culture medium, caused a significant modulation (ca. 10%, i.e., 96 and 85 protein zones, respectively) of the total proteins visualized in the respective two-dimensional maps. These spots were identified by mass spectrometry analysis and were found to belong to the following functional classes: nucleotide synthesis and metabolism, damaged-protein catabolism, protein and amino acid metabolism, and carbohydrate metabolism along with DNA-related proteins and proteins involved in cell division, oxidative stress, and cell wall synthesis. PMID:17827320

Antonioli, Paolo; Lampis, Silvia; Chesini, Irene; Vallini, Giovanni; Rinalducci, Sara; Zolla, Lello; Righetti, Pier Giorgio

2007-01-01

70

Risk Factors and Outcomes of Stenotrophomonas maltophilia Bacteraemia: A Comparison with Bacteraemia Caused by Pseudomonas aeruginosa and Acinetobacter Species  

PubMed Central

Stenotrophomonas maltophilia (SM) is an important nosocomial pathogen that exhibits intrinsic resistance to various antimicrobial agents. However, the risk factors for SM bacteraemia have not been sufficiently evaluated. From January 2005 to September 2012, we retrospectively compared the clinical backgrounds and outcomes of SM bacteraemic patients (SM group) with those of bacteraemic patients due to Pseudomonas aeruginosa (PA group) or Acinetobacter species (AC group). DNA genotyping of the SM isolates using the Diversilab system was performed to investigate the genetic relationships among the isolates. The SM, PA, and AC groups included 54, 167, and 69 patients, respectively. Nine of 17 patients in the SM group receiving trimethoprim-sulfamethoxazole prophylaxis developed SM bacteraemia. Independent risk factors for SM bacteraemia were the use of carbapenems and antipseudomonal cephalosporins and SM isolation within 30 days prior to the onset of bacteraemia. Earlier SM isolation was observed in 32 of 48 patients (66.7%) with SM bacteraemia who underwent clinical microbiological examinations. Of these 32 patients, 15 patients (46.9%) had the same focus of bacteraemia as was found in the previous isolation site. The 30-day all-cause mortality rate among the SM group (33.3%) was higher than that of the PA group (21.5%, p?=?0.080) and the AC group (17.3%, p?=?0.041). The independent factor that was associated with 30-day mortality was the SOFA score. DNA genotyping of SM isolates and epidemiological data suggested that no outbreak had occurred. SM bacteraemia was associated with high mortality and should be considered in patients with recent use of broad-spectrum antibiotics or in patients with recent isolation of the organism. PMID:25375244

Hotta, Go; Matsumura, Yasufumi; Kato, Karin; Nakano, Satoshi; Yunoki, Tomoyuki; Yamamoto, Masaki; Nagao, Miki; Ito, Yutaka; Takakura, Shunji; Ichiyama, Satoshi

2014-01-01

71

[Investigation of integrons, sul1-2 and dfr genes in trimethoprim-sulfametoxazole-resistant Stenotrophomonas maltophilia strains isolated from clinical samples].  

PubMed

Stenotrophomonas maltophilia, which is a non-fermentative gram-negative bacillus, has an increasing importance in nosocomial and opportunistic infections. Since it exhibits resistance to numerous broad-spectrum antibiotics such as aminoglycosides, beta-lactams and tetracyclines, it may considerably limit empirical treatment options. Trimethoprim-sulfamethoxazole (SXT) is recommended as the first-line therapy in the treatment of S.maltophilia infections thanks to its high potency and usefulness in a range of patients. In recent years, however, studies in different geographical regions have started to report resistance to SXT. In this study, we aimed to investigate the genes sul1, sul2, dfrA9, dfrA10, dfrA20 and class I, class II integron gene cassettes which are known to play role in SXT resistance among SXT-resistant S.maltophilia strains. A total of 618 S.maltophilia strains isolated from various clinical samples of 339 patients between January 2006 and October 2011 at the laboratory of Medical Microbiology Department, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey, were included in the study. The isolates were identified by both conventional methods and the Phoenix automated identification system (Becton Dickinson, USA). SXT resistance was determined in the isolates of 32 patients (32/339, 9.4%) by both the automated system and agar dilution method of them 29 (90.6%) were hospital-acquired, and 3 (9.4%) were community-acquired. The genes which are known as SXT resistance determining genes including sul1, sul2, dfr genes, and class I and class II integron gene cassettes were analyzed by using specific primers with polymerase chain reaction in the 32 SXT-resistant isolates. Subsequently, nucleotide sequence analysis of the amplified materials was performed. As a result of this assay, the presence of class I integron gene cassette and sul1 gene were detected in one isolate. Nucleotide sequence analysis of the gene cassette revealed oxacilinase (oxa2) type of beta-lactamase, an aminoglycoside 6'-N-acetyltransferase [aac(6')-IIc], leading to resistance of aminoglycosides, and a quaternary ammonium compounds resistance gene (qacF), respectively. In conclusion, to best of our knowledge the sequences of class I integron gene cassette including oxa2, aac(6')-IIc, qacF genes were identified in S.maltophilia for the first time. It should be kept in mind that the co-presence of a class I integron gene cassette and the sul1 gene in S.maltophilia may lead to the development of multi-drug resistance and may act as a potential source for the dissemination of resistance. PMID:24819258

Ozkaya, Esra; Aydin, Faruk; Bayramoglu, Glin; Buruk, Celal Kurtulu?; Sandalli, Cemal

2014-04-01

72

Potential novel therapeutic strategies in cystic fibrosis: antimicrobial and anti-biofilm activity of natural and designed ?-helical peptides against Staphylococcus aureus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia  

PubMed Central

Background Treatment of cystic fibrosis-associated lung infections is hampered by the presence of multi-drug resistant pathogens, many of which are also strong biofilm producers. Antimicrobial peptides, essential components of innate immunity in humans and animals, exhibit relevant in vitro antimicrobial activity although they tend not to select for resistant strains. Results Three ?-helical antimicrobial peptides, BMAP-27 and BMAP-28 of bovine origin, and the artificial P19(9/B) peptide were tested, comparatively to Tobramycin, for their in vitro antibacterial and anti-biofilm activity against 15 Staphylococcus aureus, 25 Pseudomonas aeruginosa, and 27 Stenotrophomonas maltophilia strains from cystic fibrosis patients. All assays were carried out in physical-chemical experimental conditions simulating a cystic fibrosis lung. All peptides showed a potent and rapid bactericidal activity against most P. aeruginosa, S. maltophilia and S. aureus strains tested, at levels generally higher than those exhibited by Tobramycin and significantly reduced biofilm formation of all the bacterial species tested, although less effectively than Tobramycin did. On the contrary, the viability-reducing activity of antimicrobial peptides against preformed P. aeruginosa biofilms was comparable to and, in some cases, higher than that showed by Tobramycin. Conclusions The activity shown by ?-helical peptides against planktonic and biofilm cells makes them promising lead compounds for future development of novel drugs for therapeutic treatment of cystic fibrosis lung disease. PMID:22823964

2012-01-01

73

The Binding of Triclosan to SmeT, the Repressor of the Multidrug Efflux Pump SmeDEF, Induces Antibiotic Resistance in Stenotrophomonas maltophilia  

PubMed Central

The wide utilization of biocides poses a concern on the impact of these compounds on natural bacterial populations. Furthermore, it has been demonstrated that biocides can select, at least in laboratory experiments, antibiotic resistant bacteria. This situation has raised concerns, not just on scientists and clinicians, but also on regulatory agencies, which are demanding studies on the impact that the utilization of biocides may have on the development on resistance and consequently on the treatment of infectious diseases and on human health. In the present article, we explored the possibility that the widely used biocide triclosan might induce antibiotic resistance using as a model the opportunistic pathogen Stenotrophomonas maltophilia. Biochemical, functional and structural studies were performed, focusing on SmeDEF, the most relevant antibiotic- and triclosan-removing multidrug efflux pump of S. maltophilia. Expression of smeDEF is regulated by the repressor SmeT. Triclosan released SmeT from its operator and induces the expression of smeDEF, thus reducing the susceptibility of S. maltophilia to antibiotics in the presence of the biocide. The structure of SmeT bound to triclosan is described. Two molecules of triclosan were found to bind to one subunit of the SmeT homodimer. The binding of the biocide stabilizes the N terminal domain of both subunits in a conformation unable to bind DNA. To our knowledge this is the first crystal structure obtained for a transcriptional regulator bound to triclosan. This work provides the molecular basis for understanding the mechanisms allowing the induction of phenotypic resistance to antibiotics by triclosan. PMID:21738470

Romero, Antonio; Martnez, Jos L.

2011-01-01

74

Two Different rpf Clusters Distributed among a Population of Stenotrophomonas maltophilia Clinical Strains Display Differential Diffusible Signal Factor Production and Virulence Regulation  

PubMed Central

The quorum-sensing (QS) system present in the emerging nosocomial pathogen Stenotrophomonas maltophilia is based on the signaling molecule diffusible signal factor (DSF). Production and detection of DSF are governed by the rpf cluster, which encodes the synthase RpfF and the sensor RpfC, among other components. Despite a well-studied system, little is known about its implication in virulence regulation in S. maltophilia. Here, we have analyzed the rpfF gene from 82 S. maltophilia clinical isolates. Although rpfF was found to be present in all of the strains, it showed substantial variation, with two populations (rpfF-1 and rpfF-2) clearly distinguishable by the N-terminal region of the protein. Analysis of rpfC in seven complete genome sequences revealed a corresponding variability in the N-terminal transmembrane domain of its product, suggesting that each RpfF variant has an associated RpfC variant. We show that only RpfCRpfF-1 variant strains display detectable DSF production. Heterologous rpfF complementation of ?rpfF mutants of a representative strain of each variant suggests that RpfF-2 is, however, functional and that the observed DSF-deficient phenotype of RpfCRpfF-2 variant strains is due to permanent repression of RpfF-2 by RpfC-2. This is corroborated by the ?rpfC mutant of the RpfCRpfF-2 representative strain. In line with this observations, deletion of rpfF from the RpfCRpfF-1 strain leads to an increase in biofilm formation, a decrease in swarming motility, and relative attenuation in the Caenorhabditis elegans and zebrafish infection models, whereas deletion of the same gene from the representative RpfCRpfF-2 strain has no significant effect on these virulence-related phenotypes. PMID:24769700

Huedo, Pol; Yero, Daniel; Martnez-Servat, Snia; Estibariz, Iratxe; Planell, Raquel; Martnez, Paula; Ruyra, ngels; Roher, Nerea; Roca, Ignasi; Vila, Jordi

2014-01-01

75

[Investigation of the presence of class 1, 2, 3 integrons and their relationships with antibiotic resistance in clinical Stenotrophomonas maltophilia isolates].  

PubMed

Stenotrophomonas maltophilia is an opportunistic emergent pathogen causing hospital-acquired infections. It is resistant to majority of the broad spectrum antibiotics due to several mechanisms which significantly limit the treatment options. Although the relationship between integrons, mobile genetic elements which play role in transferring resistance genes, and the antibiotic resistance in different gram-negative bacteria have been investigated, the data are limited in Turkey especially for S.maltophilia. The aims of this study were to detect the presence of different classes of integrons and plasmids in clinical isolates of S.maltophilia and to investigate the antibiotic resistance profiles of those isolates. One hundred S.maltophilia strains isolated from various clinical samples (32 sputum, 25 tracheal aspirates, 9 urine and blood, 7 exudates and catheters, 4 sterile body fluids and wounds, 2 CSF, 1 conjunctiva) in our microbiology laboratory during January 2011-September 2012, were included in the study. The isolates were identified by VITEK2 Compact (BioMerieux, France) or Phoenix 100 (BD, USA) automatized systems, and the susceptibilities of the strains to levofloxacin, chloramphenicol, ceftazidime and trimethoprim/sulfamethoxazol (SXT) were evaluated via broth microdilution method according to the CLSI recommendations. Class 1 (intI-1), class 2 (intI-2), class 3 (intI-3) integron gene cassettes and integron 5'-3' conserved gene regions (intI-5'-3'CS) were investigated by polymerase chain reaction (PCR) using specific primers in all of the strains. Nucleotide sequence analysis of PCR products was performed in case of positive result, and the presence and size of plasmids were further investigated. The susceptibility rates of S.maltophilia strains to ceftazidime, chloramphenicol, SXT and levofloxacin were found as 24%, 66%, 93% and 95%, respectively, while MIC50 and MIC90 values were 64-128 g/ml, 8-16 g/ml, 1/19-2/38 g/ml and 1-2 g/ml, respectively. In PCR amplification with intI-1, intI-2 and intI-3 primers, 12%, 2% and 10% of the isolates yielded expectative bands, respectively. DNA sequence analysis of the amplified products revealed five isolates to harbour intI-1 gene, while intI class 2 and class 3 genes were not detected in any of the strains. Furthermore in PCR amplification with intI-5'CS and 3'CS primers, 20% of the strains yielded expected bands. Sequence analysis of these amplicons revealed the presence of quaternary ammonium compound resistance protein genes (qacL) in two, aminoglycoside adenyltransferase gene (aadA) in one and integron-associated recombination site (attI1) genes in five strains. Additionally, the presence of plasmids have been detected in 9 (9%) of the strains, however all of them was integron-negative. The sizes of plasmids were 2340, 1350, 2760, 18600, 20000, 3570-2540, 2510 and 5000-2540 base pairs, respectively. When the antibiotic susceptibility patterns of strains were compared with the presence of intI gene regions, no statistically significant relationship was observed (p> 0.05). In conclusion, the demonstration of integron class 1 genes and plasmids among clinical S.maltophilia strains is regarded as a warning data to indicate the potential for spread of those resistant strains in our hospital. PMID:25706729

Usta, Egemen; Ero?lu, Cafer; Yan?k, Keramettin; Karada?, Adil; Gney, Akif Koray; Gnayd?n, Murat

2015-01-01

76

Copper Enhanced Monooxygenase Activity and FT-IR Spectroscopic Characterisation of Biotransformation Products in Trichloroethylene Degrading Bacterium: Stenotrophomonas maltophilia PM102  

PubMed Central

Stenotrophomonas maltophilia PM102 (NCBI GenBank Acc. no. JQ797560) is capable of growth on trichloroethylene as the sole carbon source. In this paper, we report the purification and characterisation of oxygenase present in the PM102 isolate. Enzyme activity was found to be induced 10.3-fold in presence of 0.7?mM copper with a further increment to 14.96-fold in presence of 0.05?mM NADH. Optimum temperature for oxygenase activity was recorded at 36C. The reported enzyme was found to have enhanced activity at pH 5 and pH 8, indicating presence of two isoforms. Maximum activity was seen on incubation with benzene compared to other substrates like TCE, chloroform, toluene, hexane, and petroleum benzene. Km and Vmax for benzene were 3.8?mM and 340?U/mg/min and those for TCE were 2.1?mM and 170?U/mg/min. The crude enzyme was partially purified by ammonium sulphate precipitation followed by dialysis. Zymogram analysis revealed two isoforms in the 70% purified enzyme fraction. The activity stain was more prominent when the native gel was incubated in benzene as substrate in comparison to TCE. Crude enzyme and purified enzyme fractions were assayed for TCE degradation by the Fujiwara test. TCE biotransformation products were analysed by FT-IR spectroscopy. PMID:24083236

Mukherjee, Piyali; Roy, Pranab

2013-01-01

77

A cyclic AMP receptor protein-regulated cell-cell communication system mediates expression of a FecA homologue in Stenotrophomonas maltophilia.  

PubMed

Stenotrophomonas maltophilia WR-C possesses an rpf/diffusible signal factor (DSF) cell-cell communication system. It produces cis-Delta2-11-methyl-dodecenoic acid, a DSF, and seven structural derivatives, which require rpfF and rpfB for synthesis. Acquisition of iron from the environment is important for bacterial growth as well as the expression of virulence genes. We identified a gene homologous to fecA, which encodes a ferric citrate receptor that transports exogenous siderophore ferric citrate from the environment into the bacterial periplasm. Western blot analysis with anti-FecA-His(6) antibody showed that the FecA homologue was induced in the iron-depleted medium supplemented with a low concentration of ferric citrate. Deletion of rpfF or rpfB resulted in reduced FecA expression compared to the wild type. Synthetic DSF restored FecA expression by the DeltarpfF mutant to the wild-type level. Reverse transcription-PCR showed that the fecA transcript was decreased in the DeltarpfF mutant compared to the wild type. These data suggest that DSF affected the level of fecA mRNA. Transposon inactivation of crp, which encodes cyclic AMP (cAMP) receptor protein (CRP) resulted in reduced FecA expression and rpfF transcript level. Putative CRP binding sites were located upstream of the rpfF promoter, indicating that the effect of CRP on FecA is through the rpf/DSF pathway and by directly controlling rpfF. We propose that CRP may serve as a checkpoint for iron uptake, protease activity, and hemolysis in response to environmental changes such as changes in concentrations of glucose, cAMP, iron, or DSF. PMID:17574998

Huang, Tzu-Pi; Wong, Amy C Lee

2007-08-01

78

Stenotrophomonas, Mycobacterium, and Streptomyces in home dust and air: associations with moldiness and other home/family characteristics  

EPA Science Inventory

Abstract Aims: (1) To investigate the dustborne and airborne bacterial concentrations of three emerging moisture-related bacteria: Stenotrophomonas maltophilia, Streptomyces, and Mycobacterium. (2) To study the association between these bacteria concentrations and Environmenta...

79

The versatility and adaptation of bacteria from the genus Stenotrophomonas  

SciTech Connect

The genus Stenotrophomonas comprises at least eight species. These bacteria are found throughout the environment, particularly in close association with plants. Strains of the most predominant species, Stenotrophomonas maltophilia, have an extraordinary range of activities that include beneficial effects for plant growth and health, the breakdown of natural and man-made pollutants that are central to bioremediation and phytoremediation strategies and the production of biomolecules of economic value, as well as detrimental effects, such as multidrug resistance, in human pathogenic strains. Here, we discuss the versatility of the bacteria in the genus Stenotrophomonas and the insight that comparative genomic analysis of clinical and endophytic isolates of S. maltophilia has brought to our understanding of the adaptation of this genus to various niches.

Ryan, R.P.; van der Lelie, D.; Monchy, S.; Cardinale, M.; Taghavi, S.; Crossman, L.; Avison, M. B.; Berg, G.; Dow, J. M.

2009-07-01

80

Selenite precipitation by a rhizospheric strain of Stenotrophomonas sp. isolated from the root system of Astragalus bisulcatus: a biotechnological perspective  

Microsoft Academic Search

A bacterial strain (SeITE02), related to the species Stenotrophomonas maltophilia and resistant to selenite (SeIV) up to 50 mM in the growth medium, was isolated from rhizospheric soil of a selenium hyperaccumulator plant, the legume Astragalus bisulcatus. The influence of SeIV on the active growth of this Se-tolerant bacterial strain has been investigated in oxic conditions, along with the isolate's

Simona Di Gregorio; Silvia Lampis; Giovanni Vallini

2005-01-01

81

A novel bacterial isolate Stenotrophomonas maltophilia as living factory for synthesis of gold nanoparticles  

Microsoft Academic Search

BACKGROUND: The synthesis of gold nanoparticles (GNPs) has received considerable attention with their potential applications in various life sciences related applications. Recently, there has been tremendous excitement in the study of nanoparticles synthesis by using some natural biological system, which has led to the development of various biomimetic approaches for the growth of advanced nanomaterials. In the present study, we

Yogesh Nangia; Nishima Wangoo; Nisha Goyal; G Shekhawat; C Raman Suri

2009-01-01

82

De-novo synthesis of 2-phenylethanol by Enterobacter sp. CGMCC 5087  

PubMed Central

Background 2-phenylethanl (2-PE) and its derivatives are important chemicals, which are widely used in food materials and fine chemical industries and polymers and its also a potentially valuable alcohol for next-generation biofuel. However, the biosynthesis of 2-PE are mainly biotransformed from phenylalanine, the price of which barred the production. Therefore, it is necessary to seek more sustainable technologies for 2-PE production. Results A new strain which produces 2-PE through the phenylpyruvate pathway was isolated and identified as Enterobacter sp. CGMCC 5087. The strain is able to use renewable monosaccharide as the carbon source and NH4Cl as the nitrogen source to produce 2-PE. Two genes of rate-limiting enzymes, chorismate mutase p-prephenate dehydratase (PheA) and 3-deoxy-d-arabino-heptulosonic acid 7-phosphate synthase (DAHP), were cloned from Escherichia coli and overexpressed in E. sp. CGMCC 5087. The engineered E. sp. CGMCC 5087 produces 334.9mgL-1 2-PE in 12h, which is 3.26 times as high as the wild strain. Conclusions The phenylpyruvate pathway and the substrate specificity of 2-keto-acid decarboxylase towards phenylpyruvate were found in E. sp. CGMCC 5087. Combined with the low-cost monosaccharide as the substrate, the finding provides a novel and potential way for 2-PE production. PMID:24766677

2014-01-01

83

Pseudomonas maltophilia, an Alcaligenes-like Species  

Microsoft Academic Search

SUMMARY Pseudomonas maltophilia is frequently encountered in specimens submitted to the clinical laboratory for bacteriological examination. This report describes morpho- logical, physiological and serological attributes of this species. Photomicrographs show the presence of polar multitrichous flagella in stained preparations. These pseudomonads do not produce acid from glucose but readily produce acidity from maltose oxidation. A historical review of the epithet

R. Hugh; EWDOKIA RYSCHENKOW

1961-01-01

84

Stenotrophomonas, Mycobacterium, and Streptomyces in home dust and air: Associations with moldiness and other home/family characteristics  

PubMed Central

Respiratory illnesses have been linked to childrens exposures to water-damaged homes. Therefore, understanding the microbiome in water-damaged homes is critical to preventing these illnesses. Few studies have quantified bacterial contamination, especially specific species, in water-damaged homes. We collected air and dust samples in twenty-one low-mold homes and twenty-one high-mold homes. The concentrations of three bacteria/genera, Stenotrophomonas maltophilia, Streptomyces sp. and Mycobacterium sp., were measured in air and dust samples using quantitative PCR (QPCR). The concentrations of the bacteria measured in the air samples were not associated with any specific home characteristic based on multiple regression models. However, higher concentrations of S. maltophilia in the dust samples were associated with water damage, i.e. with higher floor surface moisture and higher concentrations of moisture-related mold species. The concentrations of Streptomyces and Mycobacterium sp. had similar patterns and may be partially determined by human and animal occupants and outdoor sources of these bacteria. PMID:23397905

Kettleson, Eric; Kumar, Sudhir; Reponen, Tiina; Vesper, Stephen; Mheust, Delphine; Grinshpun, Sergey A.; Adhikari, Atin

2013-01-01

85

Stenotrophomonas, Achromobacter, and nonmelioid Burkholderia species: antimicrobial resistance and therapeutic strategies.  

PubMed

Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and nonmelioid Burkholderia species, namely, Burkholderia cepacia complex, collectively are a group of troublesome nonfermenters. Although not inherently virulent organisms, these environmental Gram negatives can complicate treatment in those who are immunocompromised, critically ill in the intensive care unit and those patients with suppurative lung disease, such as cystic fibrosis. Through a range of intrinsic antimicrobial resistance mechanisms, virulence factors, and the ability to survive in biofilms, these opportunistic pathogens are well suited to persist, both in the environment and the host. Treatment recommendations are hindered by the difficulties in laboratory identification, the lack of reproducibility of antimicrobial susceptibility testing, the lack of clinical breakpoints, and the absence of clinical outcome data. Despite trimethoprim-sulfamethoxazole often being the mainstay of treatment, resistance is widely encountered, and alternative regimens, including combination therapy, are often used. This review will highlight the important aspects and unique challenges that these three nonfermenters pose, and, in the absence of clinical outcome data, our therapeutic recommendations will be based on reported antimicrobial susceptibility and pharmacokinetic/pharmacodynamic profiles. PMID:25643274

Abbott, Iain J; Peleg, Anton Y

2015-02-01

86

Selenite precipitation by a rhizospheric strain of Stenotrophomonas sp. isolated from the root system of Astragalus bisulcatus: a biotechnological perspective.  

PubMed

A bacterial strain (SeITE02), related to the species Stenotrophomonas maltophilia and resistant to selenite (SeIV) up to 50 mM in the growth medium, was isolated from rhizospheric soil of a selenium hyperaccumulator plant, the legume Astragalus bisulcatus. The influence of SeIV on the active growth of this Se-tolerant bacterial strain has been investigated in oxic conditions, along with the isolate's ability to reduce selenite to elemental selenium (Se(0)). Interestingly, concentrations of 0.5 mM SeIV were wholly reduced by strain SeITE02 in liquid culture within 52 h. Moreover, 87% of SeIV added to the growth medium at the initial concentration of 2.0 mM underwent again reduction in 120 h. Actually, a selenite-mediated induction of a sort of adaptive response to detrimental SeIV effects magnified the efficiency of SeITE02 in reducing this toxic oxyanion. Furthermore, the SeIV influence on cell morphology of strain SeITE02 was evidenced by phase-contrast and electron microscopy analyses. In particular, transmission electron microscopy (TEM)-energy-dispersive X-ray (EDX) analysis of S. maltophilia strain SeITE02, grown in presence of SeIV, showed electron-dense Se(0) granules either in the cell cytoplasm or in the extracellular space. Therefore, the capability of strain SeITE02 to quickly reduce soluble and harmful SeIV to insoluble and unavailable Se(0) may be looked at as a promising exploitable option for the setup of low-cost biological treatments tailored to manage contamination in selenium-laden effluents. PMID:15661289

Di Gregorio, Simona; Lampis, Silvia; Vallini, Giovanni

2005-02-01

87

Stenotrophomonas maltophilia SeITE02, a New Bacterial Strain Suitable for Bioremediation of Selenite-Contaminated Environmental Matrices  

Microsoft Academic Search

strongly interferes with selenite removal when the two oxyanions (NO2 and SeO3 2 ) are simultaneously present, suggesting that the two reduction\\/detoxification pathways share a common enzymatic step, probably at the level of cellular transport; (iii) in vitro, selenite reduction does not take place in the membrane or periplasmic fractions but only in the cytoplasm, where maximum activity is exhibited

Paolo Antonioli; Silvia Lampis; Irene Chesini; Giovanni Vallini; Sara Rinalducci; Lello Zolla; Pier Giorgio Righetti

2007-01-01

88

Selective medium for isolation of Xanthomonas maltophilia from soil and rhizosphere environments.  

PubMed Central

A selective medium (XMSM) was developed for isolation of Xanthomonas maltophilia from bulk soil and plant rhizosphere environments. The XMSM basal medium contained maltose, tryptone, bromthymol blue, and agar. Antibiotics added to select for X. maltophilia were cycloheximide, nystatin, cephalexin, bacitracin, penicillin G, novobiocin, neomycin sulfate, and tobramycin. A comparison was made between XMSM and 1/10-strength tryptic soy broth agar for recovery of X. maltophilia from sterile and nonsterile soil infested with known X. maltophilia isolates. A recovery rate of 97% or greater for XMSM was demonstrated. XMSM was used to isolate X. maltophilia from a variety of soil and rhizosphere environments. PMID:2930173

Juhnke, M E; des Jardin, E

1989-01-01

89

Biocatalytic preparation of enantiopure ( R )-ketoprofen from its racemic ester by a new yeast isolate Citeromyces matriensis CGMCC 0573  

Microsoft Academic Search

. The yeast strain CGMCC 0573 was identified as Citeromyces matriensis and shown to be capable of enantioselectively hydrolyzing ethyl ester of (R)-Ketoprofen (2-(3-benzoylphenyl)propionic acid). The strain was isolated for the first time from soil samples through a new and efficient screening procedure in which the probability of obtaining active strains was greatly increased by using ethanol and Tween-80 alternatively

P.-F. Gong; H.-Y. Wu; J.-H. Xu; D. Shen; Y.-Y. Liu

2002-01-01

90

Purification and characterisation of a bifunctional alginate lyase from novel Isoptericola halotolerans CGMCC 5336.  

PubMed

A novel halophilic alginate-degrading microorganism was isolated from rotten seaweed and identified as Isoptericola halotolerans CGMCC5336. The lyase from the strain was purified to homogeneity by combining of ammonium sulfate fractionation and anion-exchange chromatography with a specific activity of 8409.19 U/ml and a recovery of 25.07%. This enzyme was a monomer with a molecular mass of approximately 28 kDa. The optimal temperature and pH were 50 C and pH 7.0, respectively. The lyase maintained stability at neutral pH (7.0-8.0) and temperatures below 50 C. Metal ions including Na(+), Mg(2+), Mn(2+), and Ca(2+) notably increased the activity of the enzyme. With sodium alginate as the substrate, the Km and Vmax were 0.26 mg/ml and 1.31 mg/ml min, respectively. The alginate lyase had substrate specificity for polyguluronate and polymannuronate units in alginate molecules, indicating its bifunctionality. These excellent characteristics demonstrated the potential applications in alginate oligosaccharides production with low polymerisation degrees. PMID:24053829

Dou, Wenfang; Wei, Dan; Li, Hui; Li, Heng; Rahman, Muhammad Masfiqur; Shi, Jinsong; Xu, Zhenghong; Ma, Yanhe

2013-11-01

91

Screening, identification and culture optimization of a newly isolated aromatic nitrilase-producing bacterium--Pseudomonas putida CGMCC3830.  

PubMed

Microbial nitrilases have attracted increasing attention in nitrile hydrolysis for carboxylic acid production in recent years. A bacterium with nitrilase activity was isolated and identified as Pseudomonas putida CGMCC3830 based on its morphology, physiological and biochemical characteristics, as well as 16S rRNA gene sequence. The nitrilase production was optimized by varying culture conditions using the one-factor-at-a-time method and response surface methodology. Glycerol 13.54 g/L, tryptone 11.59 g/L, yeast extract 5.21 g/L, KH2PO4 1 g/L, NaCl 1 g/L, urea 1 g/L, initial pH 6.0 and culture temperature 30 degrees C were proved to be the optimal culture conditions. It resulted in the maximal nitrilase production of 36.12 U/mL from 2.02 U/mL. Investigations on substrate specificity demonstrate P. putida nitrilase preferentially hydrolyze aromatic nitriles. When applied in nicotinic acid synthesis, 2 mg/mL P. putida cells completely hydrolyzed 20.8 g/L 3-cyanopyridine into nicotinic acid in 90 min. The results indicated P. putida CGMCC3830 displayed potential for industrial production of nicotinic acid. PMID:25007577

Zhu, Xiaoyan; Gong, Jinsong; Li, Heng; Lu, Zhenming; Zhou, Zhemin; Shi, Jinsong; Xu, Zhenghong

2014-03-01

92

Biocatalytic preparation of enantiopure ( R)-ketoprofen from its racemic ester by a new yeast isolate Citeromyces matriensis CGMCC 0573.  

PubMed

The yeast strain CGMCC 0573 was identified as Citeromyces matriensis and shown to be capable of enantioselectively hydrolyzing ethyl ester of ( R)-Ketoprofen (2-(3-benzoylphenyl)propionic acid). The strain was isolated for the first time from soil samples through a new and efficient screening procedure in which the probability of obtaining active strains was greatly increased by using ethanol and Tween-80 alternatively as additives during the enrichment culture. Studies of the culture conditions and catalytic performance of Citeromyces matriensis CGMCC 0573 showed that the enzyme occurs constitutively in the cells and its production is enhanced by feeding with Tween-80 during the early period of cultivation. Yeast extract was found to be beneficial both for growth and for esterase production. The optimal temperature and pH for the bioconversion were 40 degrees C and pH 8.0, respectively. Biotransformation using resting cells cultured in a flask with baffles and magnetic stirring and in the presence of 50 mM substrate resulted in the production of ( R)-ketoprofen at 93% ee (enantiomeric excess) and at 42.6% conversion. PMID:12021791

Gong, P-F; Wu, H-Y; Xu, J-H; Shen, D; Liu, Y-Y

2002-05-01

93

Protein purification, crystallization and preliminary X-ray diffraction analysis of L-arabinose isomerase from Lactobacillus fermentum CGMCC2921.  

PubMed

L-Arabinose isomerase (AI) catalyzes the isomerization of L-arabinose to L-ribulose, as well as that of D-galactose to D-tagatose. A thermophilic AI derived from Lactobacillus fermentum CGMCC2921 (LFAI) was overexpressed in Escherichia coli BL21 (DE3). This enzyme was purified to over 95% purity by nickel affinity, Mono-Q ion-exchange and size-exclusion chromatography. The LFAI protein was crystallized from either 0.1?M bis-tris pH 6.5, 23% PEG 3350, 0.3?M NaCl (form 1 crystals) or 0.1?M bis-tris pH 6.0, 25% PEG monomethyl ether 5000 (form 2 crystals). Diffraction data from form 1 LFAI crystals were collected to 2.80? resolution using synchrotron radiation. The form 1 crystals belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a=85.11, b=184.57, c=186.26?, ?=?=?=90. The asymmetric unit contained six LFAI subunits, corresponding to a calculated Matthews coefficient of 2.29?3?Da(-1) and a solvent content of 46.22%. PMID:25615964

Xu, Zheng; Li, Sha; Liang, Jinfeng; Feng, Xiaohai; Xu, Hong

2015-01-01

94

Revealing Differences in Metabolic Flux Distributions between a Mutant Strain and Its Parent Strain Gluconacetobacter xylinus CGMCC 2955  

PubMed Central

A better understanding of metabolic fluxes is important for manipulating microbial metabolism toward desired end products, or away from undesirable by-products. A mutant strain, Gluconacetobacter xylinus AX2-16, was obtained by combined chemical mutation of the parent strain (G. xylinus CGMCC 2955) using DEC (diethyl sulfate) and LiCl. The highest bacterial cellulose production for this mutant was obtained at about 11.75 g/L, which was an increase of 62% compared with that by the parent strain. In contrast, gluconic acid (the main byproduct) concentration was only 5.71 g/L for mutant strain, which was 55.7% lower than that of parent strain. Metabolic flux analysis indicated that 40.1% of the carbon source was transformed to bacterial cellulose in mutant strain, compared with 24.2% for parent strain. Only 32.7% and 4.0% of the carbon source were converted into gluconic acid and acetic acid in mutant strain, compared with 58.5% and 9.5% of that in parent strain. In addition, a higher flux of tricarboxylic acid (TCA) cycle was obtained in mutant strain (57.0%) compared with parent strain (17.0%). It was also indicated from the flux analysis that more ATP was produced in mutant strain from pentose phosphate pathway (PPP) and TCA cycle. The enzymatic activity of succinate dehydrogenase (SDH), which is one of the key enzymes in TCA cycle, was 1.65-fold higher in mutant strain than that in parent strain at the end of culture. It was further validated by the measurement of ATPase that 3.536.41 fold higher enzymatic activity was obtained from mutant strain compared with parent strain. PMID:24901455

Liu, Miao; Yang, Xiao-Ning; Zhu, Hui-Xia; Jia, Yuan-Yuan; Jia, Shi-Ru; Piergiovanni, Luciano

2014-01-01

95

Revealing differences in metabolic flux distributions between a mutant strain and its parent strain Gluconacetobacter xylinus CGMCC 2955.  

PubMed

A better understanding of metabolic fluxes is important for manipulating microbial metabolism toward desired end products, or away from undesirable by-products. A mutant strain, Gluconacetobacter xylinus AX2-16, was obtained by combined chemical mutation of the parent strain (G. xylinus CGMCC 2955) using DEC (diethyl sulfate) and LiCl. The highest bacterial cellulose production for this mutant was obtained at about 11.75 g/L, which was an increase of 62% compared with that by the parent strain. In contrast, gluconic acid (the main byproduct) concentration was only 5.71 g/L for mutant strain, which was 55.7% lower than that of parent strain. Metabolic flux analysis indicated that 40.1% of the carbon source was transformed to bacterial cellulose in mutant strain, compared with 24.2% for parent strain. Only 32.7% and 4.0% of the carbon source were converted into gluconic acid and acetic acid in mutant strain, compared with 58.5% and 9.5% of that in parent strain. In addition, a higher flux of tricarboxylic acid (TCA) cycle was obtained in mutant strain (57.0%) compared with parent strain (17.0%). It was also indicated from the flux analysis that more ATP was produced in mutant strain from pentose phosphate pathway (PPP) and TCA cycle. The enzymatic activity of succinate dehydrogenase (SDH), which is one of the key enzymes in TCA cycle, was 1.65-fold higher in mutant strain than that in parent strain at the end of culture. It was further validated by the measurement of ATPase that 3.53-6.41 fold higher enzymatic activity was obtained from mutant strain compared with parent strain. PMID:24901455

Zhong, Cheng; Li, Fei; Liu, Miao; Yang, Xiao-Ning; Zhu, Hui-Xia; Jia, Yuan-Yuan; Jia, Shi-Ru; Piergiovanni, Luciano

2014-01-01

96

Degradation Potential of Protocatechuate 3,4-Dioxygenase from Crude Extract of Stenotrophomonas maltophilia Strain KB2 Immobilized in Calcium Alginate Hydrogels and on Glyoxyl Agarose  

PubMed Central

Microbial intradiol dioxygenases have been shown to have a great potential for bioremediation; however, their structure is sensitive to various environmental and chemical agents. Immobilization techniques allow for the improvement of enzyme properties. This is the first report on use of glyoxyl agarose and calcium alginate as matrixes for the immobilization of protocatechuate 3,4-dioxygenase. Multipoint attachment of the enzyme to the carrier caused maintenance of its initial activity during the 21 days. Immobilization of dioxygenase in calcium alginate or on glyoxyl agarose resulted in decrease in the optimum temperature by 5C and 10C, respectively. Entrapment of the enzyme in alginate gel shifted its optimum pH towards high-alkaline pH while immobilization of the enzyme on glyoxyl agarose did not influence pH profile of the enzyme. Protocatechuate 3,4-dioygenase immobilized in calcium alginate showed increased activity towards 2,5-dihydroxybenzoate, caffeic acid, 2,3-dihydroxybenzoate, and 3,5-dihydroxybenzoate. Slightly lower activity of the enzyme was observed after its immobilization on glyoxyl agarose. Entrapment of the enzyme in alginate gel protected it against chelators and aliphatic alcohols while its immobilization on glyoxyl agarose enhanced enzyme resistance to inactivation by metal ions. PMID:24693536

Krysiak, Marta

2014-01-01

97

Degradation potential of protocatechuate 3,4-dioxygenase from crude extract of Stenotrophomonas maltophilia strain KB2 immobilized in calcium alginate hydrogels and on glyoxyl agarose.  

PubMed

Microbial intradiol dioxygenases have been shown to have a great potential for bioremediation; however, their structure is sensitive to various environmental and chemical agents. Immobilization techniques allow for the improvement of enzyme properties. This is the first report on use of glyoxyl agarose and calcium alginate as matrixes for the immobilization of protocatechuate 3,4-dioxygenase. Multipoint attachment of the enzyme to the carrier caused maintenance of its initial activity during the 21 days. Immobilization of dioxygenase in calcium alginate or on glyoxyl agarose resulted in decrease in the optimum temperature by 5 C and 10 C, respectively. Entrapment of the enzyme in alginate gel shifted its optimum pH towards high-alkaline pH while immobilization of the enzyme on glyoxyl agarose did not influence pH profile of the enzyme. Protocatechuate 3,4-dioygenase immobilized in calcium alginate showed increased activity towards 2,5-dihydroxybenzoate, caffeic acid, 2,3-dihydroxybenzoate, and 3,5-dihydroxybenzoate. Slightly lower activity of the enzyme was observed after its immobilization on glyoxyl agarose. Entrapment of the enzyme in alginate gel protected it against chelators and aliphatic alcohols while its immobilization on glyoxyl agarose enhanced enzyme resistance to inactivation by metal ions. PMID:24693536

Guzik, Urszula; Hupert-Kocurek, Katarzyna; Krysiak, Marta; Wojcieszy?ska, Danuta

2014-01-01

98

Immunoelectron microscopic demonstration of an esterase on the outer membrane of Xanthomonas maltophilia.  

PubMed Central

Xanthomonas maltophilia (later synonym of Pseudomonas maltophilia), an ubiquitous species, is known to show proteolytic and lipolytic activities. A cell-bound esterase which hydrolyzes beta-naphthyl acetate during growth has been extracted from a strain isolated from soil. Because of its strongly hydrophobic character, the enzyme could be efficiently solubilized only by Triton X-100. This nonionic detergent must be added in polyacrylamide gels to permit migration. Polyclonal rabbit antibodies raised against the Triton-soluble esterase complex were used to localize the enzyme at the ultrastructural level. Electron microscopy of cell sections of this organism and immunogold labeling demonstrated that the enzyme was located on the outer membrane. Such an envelope-bound esterase may produce assimilable substrates for X. maltophilia which can grow in various environments. Images PMID:2495761

Debette, J; Prensier, G

1989-01-01

99

Presence of 3-O-methyl-l-xylose in the lipopolysaccharide of Pseudomonas maltophilia N.C.T.C. 10257.  

PubMed Central

3-O-Methyl-L-xylose was isolated from whole cells of Pseudomonas maltophilia N.C.T.C. 10257. The sugar is a component of lipopolysaccharide from which a polysaccharide also containing L-rhamnose and L-xylose was released by mild acid hydrolysis. 3-O-Methyl-L-xylose was absent from five other strains of Ps. maltophilia and one strain of Pseudomonas geniculata. PMID:869917

Brown, F; Neal, D J; Wilkinson, S G

1977-01-01

100

Metabolic flux analysis of Arthrobacter sp. CGMCC 3584 for cAMP production based on 13C tracer experiments and gas chromatography-mass spectrometry.  

PubMed

Arthrobacter sp. CGMCC 3584 are able to produce cAMP from glucose by the purine synthesis pathway via de novo or salvage biosynthesis. In order to gain an improved understanding of its metabolism, (13)C-labeling experiment and gas chromatography-mass spectrometry (GC-MS) analysis were employed to determine the metabolic network structure and estimate the intracellular fluxes. GC-MS analysis helps to reflect the activity of the intracellular pathways and reactions. The metabolic network mainly contains glycolytic and pentose phosphate pathways, the tricarboxylic acid cycle, and the inactive glyoxylate shunt. Hypoxanthine as a precursor of cAMP and sodium fluoride as an inhibitor of glycolysis were found to increase the cAMP production, as well as the flux through the PP pathway. The effects of adding hypoxanthine and sodium fluoride are discussed based on the enzyme assays and metabolic flux analysis. In conclusion, our results provide quantitative insights into how cells manipulate the metabolic network under different culture conditions and this may be of value in metabolic regulation for desirable production. PMID:24056081

Niu, Huanqing; Chen, Yong; Yao, Shiwei; Liu, Lixia; Yang, Chen; Li, Bingbing; Liu, Dong; Xie, Jingjing; Chen, Xiaochun; Wu, Jinglan; Ying, Hanjie

2013-12-01

101

Engineering chlorpyrifos-degrading Stenotrophomonas sp. YC-1 for heavy metal accumulation and enhanced chlorpyrifos degradation.  

PubMed

Many ecosystems are currently co-contaminated with pesticides and heavy metals, such as chlorpyrifos and cadmium. A promising strategy to remediate mixed chlorpyrifos-cadmium-contaminated sites is the use of chlorpyrifos-degrading bacteria endowed with cadmium removal capabilities. In this work, a gene coding for synthetic phytochelatins (EC20) with high cadmium-binding capacity was introduced into a chlorpyrifos-degrading bacterium, Stenotrophomonas sp. YC-1, resulting in an engineered strain with both cadmium accumulation and chlorpyrifos degradation capabilities. To improve the cadmium-binding efficiency of whole cells, EC20 was displayed on the cell surface of Stenotrophomonas sp. YC-1 using the truncated ice nucleation protein (INPNC) anchor. The surface localization of the INPNC-EC20 fusion protein was demonstrated by cell fractionation, Western blot analysis, and immunofluorescence microscopy. Expression of EC20 on the cell surface not only improved cadmium binding, but also alleviated the cellular toxicity of cadmium. As expected, the chlorpyrifos degradation rate was reduced in the presence of cadmium for cells without EC20 expression. However, expression of EC20 (higher cadmium accumulation) completely restored the level of chlorpyrifos degradation. These results demonstrated that EC20 expression not only enhanced cadmium accumulation, but also reduced the toxic effect of cadmium on chlorpyrifos degradation. PMID:25151179

Liu, Ruihua; Jiang, Hong; Xu, Ping; Qiao, Chuanling; Zhou, Qixing; Yang, Chao

2014-11-01

102

Purification of Two Nitrate Reductases from Xanthomonas maltophilia Grown in Aerobic Cultures  

PubMed Central

Xanthomonas maltophilia ATCC 17666 is an obligate aerobe that accumulates nitrite when grown on nitrate. Spectra of membranes from nitrate-grown cells exhibited b-type cytochrome peaks and A615-630 indicative of d-type cytochrome but no absorption peaks corresponding to c-type cytochromes. The nitrate reductase (NR) activity was located in the membrane fraction. Triton X-100-extracted reduced methyl viologen-NRs were purified on DE-52, hydroxylapatite, and Sephacryl S-300 columns to specific activities of 52 to 67 ?mol of nitrite formed per min per mg of protein. The cytochrome-containing NRI separated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis into a 135-kDa ?-subunit, a 64-kDa ?-subunit, and a 23-kDa ?-subunit with relative band intensities indicative of a 1:1:1 ?/?/? subunit ratio and a Mr of 222,000. The electronic spectrum of dithionite-reduced purified NR displayed peaks at 425, 528, and 558 nm, indicative of the presence of a cytochrome b, an interpretation consistent with the pyridine hemochrome spectrum formed. The cytochrome b of the NR was reduced under anaerobic conditions by menadiol and oxidized by nitrate with the production of nitrite. This NR contained 0.96 Mo, 12.5 nonheme iron, and 1 heme per 222 kDa: molybdopterin was detected with the Neurospora crassa nit-1 assay. A smaller reduced methyl viologen-NR (169 kDa), present in various concentrations in the Triton X-100 preparations, lacked a cytochrome spectrum and did not oxidize menadiol. The characteristics of the NRs and the absence of c-type cytochromes provide insights into why X. maltophilia accumulates nitrite. Images PMID:16348805

Ketchum, Paul A.; Payne, William J.

1992-01-01

103

Degradative potential of Stenotrophomonas strain HPC383 having genes homologous to dmp operon.  

PubMed

A strain, Stenotrophomonas HPC383 is isolated from effluent treatment plant treating wastewater from pesticide industry; degrades various aromatic compounds (cresols, phenol, catechol, 4methyl-catechol and hydroquinone) and crude oil, as determined through HPLC and GC analysis. Culture HPC383 could degrade (%) various compounds (1 mM) from a mixture: phenol - 99, p-cresol - 100, 4-methylcatechol - 96 and hydroquinone - 43 within 48 h of incubation, whereas it took 7 days to degrade 94% of 0.5% crude oil. Gene locus dmpN, to identify phenol degrading capacity was determined by PCR followed by southern analysis. The sequenced DNA fragment exhibited 99% sequence similarity to phenol hydroxylase gene from Arthrobacter sp. W1 (FJ610336). Amino acid sequence analysis of phenol hydroxylase reveals it to belong to high-Ks (affinity constant) group. Application of HPC383 in bioremediation of aquatic and terrestrial sites contaminated with petrochemical has been suggested. PMID:21123060

Verma, Vinita; Raju, Sajan C; Kapley, Atya; Kalia, Vipin Chandra; Kanade, Gajanan S; Daginawala, Hatim F; Purohit, Hemant J

2011-02-01

104

Characterization of three antifungal calcite-forming bacteria, Arthrobacter nicotianae KNUC2100, Bacillus thuringiensis KNUC2103, and Stenotrophomonas maltophilia KNUC2106, derived from the Korean islands, Dokdo and their application on mortar.  

PubMed

Crack remediation on the surface of cement mortar using microbiological calcium carbonate (CaCO3) precipitation (MICP) has been investigated as a microbial sealing agent on construction materials. However, MICP research has never acknowledged the antifungal properties of calcite-forming bacteria (CFB). Since fungal colonization on concrete surfaces can trigger biodeterioration processes, fungi on concrete buildings have to be prevented. Therefore, to develop a microbial sealing agent that has antifungal properties to remediate cement cracks without deteriorative fungal colonization, we introduced an antifungal CFB isolated from oceanic islands (Dokdo islands, territory of South Korea, located at the edge of the East Sea in Korea.). The isolation of CFB was done using B4 or urea-CaCl2 media. Furthermore, antifungal assays were done using the pairing culture and disk diffusion methods. Five isolated CFB showed CaCO3 precipitation and antifungal activities against deteriorative fungal strains. Subsequently, five candidate bacteria were identified using 16S rDNA sequence analysis. Crack remediation, fungi growth inhibition, and water permeability reduction of antifungal CFB-treated cement surfaces were tested. All antifungal CFB showed crack remediation abilities, but only three strains (KNUC2100, 2103, and 2106) reduced the water permeability. Furthermore, these three strains showed fungi growth inhibition. This paper is the first application research of CFB that have antifungal activity, for an eco-friendly improvement of construction materials. PMID:23727794

Park, Jong-Myong; Park, Sung-Jin; Ghim, Sa-Youl

2013-09-28

105

A Three-Component Enzyme System Catalyzes the O Demethylation of the Herbicide Dicamba in Pseudomonas maltophilia DI-6  

PubMed Central

An enzyme activity which converts dicamba (2-methoxy-3,6-dichlorobenzoic acid) to 3,6-dichlorosalicylic acid in vitro has been detected in cell lysates of Pseudomonas maltophilia DI-6. Phenyl-Sepharose column chromatography of a partially purified lysate resulted in the separation of this enzyme into three separate protein components tentatively identified as an oxygenase, a ferredoxin, and a reductase. The activity of dicamba O-demethylase was dependent on oxygen and required NADH and Mg(sup2+). PMID:16535584

Wang, X.; Li, B.; Herman, P. L.; Weeks, D. P.

1997-01-01

106

Microcystin-Degrading Activity of an Indigenous Bacterial Strain Stenotrophomonas acidaminiphila MC-LTH2 Isolated from Lake Taihu  

PubMed Central

Microcystin-LR (MC-LR) and microcystin-RR (MC-RR) produced by harmful cyanobacterial blooms (HCBs) pose substantial threats to the ecosystem and public health due to their potential hepatotoxicity. Degradation of microcystins (MCs) by indigenous bacteria represents a promising method for removing MCs from fresh water without harming the aquatic environment, but only a few microcystin (MC)-degrading bacteria have been isolated and had their mechanisms reported. This study aimed to isolate indigenous bacteria from Lake Taihu, and investigate the capability and mechanism of MC degradation by these bacteria. During a Microcystis bloom, an indigenous MC-degrading bacterium designated MC-LTH2 was successfully isolated from Lake Taihu, and identified as Stenotrophomonas acidaminiphila based on phylogenetic analysis. In the presence of MC-LR together with MC-RR, the strain MC-LTH2 was capable of totally degrading both simultaneously in 8 days, at rates of 3.0 mg/(L?d) and 5.6 mg/(L?d), respectively. The degradation rates of MCs were dependent on temperature, pH, and initial MC concentration. Adda (3-amino-9-methoxy-2, 6, 8-trimethyl-10-phenyldeca-4, 6-dienoic acid) was detected as an intermediate degradation product of MCs using high performance liquid chromatography coupled with time-of-flight mass spectrometry (HPLC-TOF-MS). To the best of our knowledge, this is the first report of Stenotrophomonas acidaminiphila capable of degrading two MC analogues and other compounds containing Adda residue completely under various conditions, although the mlrA gene in the strain was not detected. These results indicate the Stenotrophomonas acidaminiphila strain MC-LTH2 possesses a significant potential to be used in bioremediation of water bodies contaminated by MC-LR and MC-RR, and is potentially involved in the degradation of MCs during the disappearance of the HCBs in Lake Taihu. PMID:24416455

Yang, Fei; Zhou, Yuanlong; Yin, Lihong; Zhu, Guangcan; Liang, Geyu; Pu, Yuepu

2014-01-01

107

Purification and characterization of a cold active alkaline protease from Stenotrophomonas sp., isolated from Kashmir, India.  

PubMed

A Psychrotolerant alkaline protease producing bacterium IIIM-ST045 was isolated from a soil sample collected from the Thajiwas glacier of Kashmir, India and identified as Stenotrophomonas sp. on the basis of its biochemical properties and 16S ribosomal gene sequencing. The strain could grow well within a temperature range of 4-37C however, showed optimum growth at 15C. The strain was found to over-produce proteases when it was grown in media containing lactose as carbon source (157.50 U mg(-1)). The maximum specific enzyme activity (398 U mg(-1)) was obtained using soya oil as nitrogen source, however, the inorganic nitrogen sources urea, ammonium chloride and ammonium sulphate showed the lowest production of 38.9, 62.2 and 57.9 U mg(-1). The enzyme was purified to 18.45 folds and the molecular weight of the partially purified protease was estimated to be ~55 kDa by SDS-PAGE analysis. The protease activity increased as the increase in enzyme concentration while as the optimum enzyme activity was found when casein (1% w/v) was used as substrate. The enzyme was highly active over a wide range of pH from 6.5 to 12.0 showing optimum activity at pH 10.0. The optimum temperature for the enzyme was 15C. Proteolytic activity reduced gradually with higher temperatures with a decrease of 56% at 40C. The purified enzyme was checked for the removal of protein containing tea stains using a silk cloth within a temperature range of 10-60C. The best washing efficiency results obtained at low temperatures indicate that the enzyme may be used for cold washing purposes of delicate fabrics that otherwise are vulnerable to high temperatures. PMID:22805828

Saba, Iram; Qazi, Parvaiz H; Rather, Shabir A; Dar, Refaz A; Qadri, Qurrat A; Ahmad, Nasier; Johri, Sarojini; Taneja, Subash C; Shawl, Sami

2012-03-01

108

Whole-genome sequence assembly of Pediococcus pentosaceus LI05 (CGMCC 7049) from the human gastrointestinal tract and comparative analysis with representative sequences from three food-borne strains  

PubMed Central

Background Strains of Pediococcus pentosaceus from food and the human gastrointestinal tract have been widely identified, and some have been reported to reduce inflammation, encephalopathy, obesity and fatty liver in animals. In this study, we sequenced the whole genome of P. pentosaceus LI05 (CGMCC 7049), which was isolated from the fecal samples of healthy volunteers, and determined its ability to reduce acute liver injury. No other genomic information for gut-borne P. pentosaceus is currently available in the public domain. Results We obtained the draft genome of P. pentosaceus LI05, which was 1,751,578bp in size and possessed a mean G?+?C content of 37.3%. This genome encoded an abundance of proteins that were protective against acids, bile salts, heat, oxidative stresses, enterocin A, arsenate and universal stresses. Important adhesion proteins were also encoded by the genome. Additionally, P. pentosaceus LI05 genes encoded proteins associated with the biosynthesis of not only three antimicrobials, including prebacteriocin, lysin and colicin V, but also vitamins and functional amino acids, such as riboflavin, folate, biotin, thiamine and gamma-aminobutyrate. A comparison of P. pentosaceus LI05 with all known genomes of food-borne P. pentosaceus strains (ATCC 25745, SL4 and IE-3) revealed that it possessed four novel exopolysaccharide biosynthesis proteins, additional putative environmental stress tolerance proteins and phage-related proteins. Conclusions This work demonstrated the probiotic properties of P. pentosaceus LI05 from the gut and the three other food-borne P. pentosaceus strains through genomic analyses. We have revealed the major genomic differences between these strains, providing a framework for understanding the probiotic effects of strain LI05, which exhibits unique physiological and metabolic properties. PMID:25349631

2014-01-01

109

Conversion of linoleic acid into 10-Hydroxy-12(Z)-octadecenoic acid by whole cells of Stenotrophomonas nitritireducens.  

PubMed

The conversion of linoleic acid into 10-hydroxy-12(Z)-octadecenoic acid by whole cells of Stenotrophomonas nitritireducens as an isolated bacterium was optimized, and the optimal temperature, pH, and cell and substrate concentrations were 30 degrees C, 7.5, and 20 and 20 g/L, respectively. Under these conditions, whole cells in a bioreactor produced 15 g/L 10-hydroxy-12(Z)-octadecenoic acid in 2 h of reaction time without detectable byproducts. Using 2 g/L linoleic acid, the cells produced 1.92 g/L 10-hydroxy-12(Z)-octadecenoic acid. These are the highest concentration and yield of 10-hydroxy-12(Z)-octadecenoic acid ever reported. PMID:18197675

Yu, In-Sik; Kim, Hye-Jung; Oh, Deok-Kun

2008-01-01

110

Feeding strategies for the enhanced production of ?-arbutin in the fed-batch fermentation of Xanthomonas maltophilia BT-112.  

PubMed

To develop a cost-effective method for the enhanced production of ?-arbutin using Xanthomonas maltophilia BT-112 as a biocatalyst, different fed-batch strategies such as constant feed rate fed-batch, constant hydroquinone (HQ) concentration fed-batch, exponential fed-batch and DO-control pulse fed-batch (DPFB) on ?-arbutin production were investigated. The research results indicated that DPFB was an effective method for ?-arbutin production. When fermentation with DO-control pulse feeding strategy to feed HQ and yeast extract was applied, the maximum concentrations of ?-arbutin and cell dry weight were 61.7 and 4.21 g/L, respectively. The ?-arbutin production was 394% higher than that of the control (batch culture) and the molar conversion yield of ?-arbutin reached 94.5% based on the amount of HQ supplied (240 mM). Therefore, the results in this work provide an efficient and easily controlled method for industrial-scale production of ?-arbutin. PMID:23722821

Liu, Chunqiao; Zhang, Peng; Zhang, Shurong; Xu, Tao; Wang, Fang; Deng, Li

2014-02-01

111

?-Dodecelactone production from safflower oil via 10-hydroxy-12(Z)-octadecenoic acid intermediate by whole cells of Candida boidinii and Stenotrophomonas nitritireducens.  

PubMed

Candida boidinii was selected as a ?-dodecelactone producer because of the highest production of ?-dodecelactone from 10-hydroxy-12(Z)-octadecenoic acid among the 11 yeast strains tested. Under the reaction conditions of pH 5.5 and 25 C with 5 g/L 10-hydroxy-12(Z)-octadecenoic acid and 30 g/L cells, whole C. boidinii cells produced 2.1 g/L ?-dodecelactone from 5 g/L 10-hydroxy-12(Z)-octadecenoic acid after 6 h, with a conversion yield of 64% (mol/mol) and a volumetric productivity of 350 mg/L/h. The production of ?-dodecelactone from safflower oil was performed by lipase hydrolysis reaction and two-step whole-cell biotransformation using Stenotrophomonas nitritireducens and C. boidinii. ?-Dodecelactone at 1.88 g/L was produced from 7.5 g/L safflower oil via 5 g/L 10-hydroxy-12(Z)-octadecenoic acid intermediate by these reactions after 8 h of reaction time, with a volumetric productivity of 235 mg/L/h and a conversion yield of 25% (w/w). To the best of the authors' knowledge, this is the highest volumetric productivity and conversion yield reported to date for the production of ?-lactone from natural oils. PMID:24967938

Jo, Ye-Seul; An, Jung-Ung; Oh, Deok-Kun

2014-07-16

112

Whole-genome sequences of five oyster-associated bacteria show potential for crude oil hydrocarbon degradation.  

PubMed

Draft genome sequences of oyster-associated Pseudomonas stutzeri strain MF28, P.alcaligenes strain OT69, P.aeruginosa strain WC55, Stenotrophomonas maltophilia strain MF89, and Microbacterium maritypicum strain MF109 are reported. Genome-wide surveys of these isolates suggest that the oyster microbiome, which remains largely understudied, has a strong potential to degrade crude oil. PMID:24092793

Chauhan, Ashvini; Green, Stefan; Pathak, Ashish; Thomas, Jesse; Venkatramanan, Raghavee

2013-01-01

113

Whole-Genome Sequences of Five Oyster-Associated Bacteria Show Potential for Crude Oil Hydrocarbon Degradation  

PubMed Central

Draft genome sequences of oyster-associated Pseudomonas stutzeri strain MF28, P.alcaligenes strain OT69, P.aeruginosa strain WC55, Stenotrophomonas maltophilia strain MF89, and Microbacterium maritypicum strain MF109 are reported. Genome-wide surveys of these isolates suggest that the oyster microbiome, which remains largely understudied, has a strong potential to degrade crude oil. PMID:24092793

Green, Stefan; Pathak, Ashish; Thomas, Jesse; Venkatramanan, Raghavee

2013-01-01

114

Ventilator-associated Pneumonia Caused by Potentially Drug-resistant Bacteria  

Microsoft Academic Search

To determine risk factors for ventilator-associated pneumonia (VAP) caused by potentially drug-resis- tant bacteria such as methicillin-resistant Staphylococcus aureus , Pseudomonas aeruginosa , Acineto- bacter baumannii , and\\/or Stenotrophomonas maltophilia , 135 consecutive episodes of VAP observed in a single ICU over a 25-mo period were prospectively studied. For all patients, VAP was diagnosed based on results of bronchoscopic protected

JEAN-LOUIS TROUILLET; JEAN CHASTRE; ALBERT VUAGNAT; MARIE-LAURE JOLY-GUILLOU; DANILE COMBAUX; MARIE-CHRISTINE DOMBRET; CLAUDE GIBERT

1998-01-01

115

Activities of Taurolidine In Vitro and in Experimental Enterococcal Endocarditis  

Microsoft Academic Search

In vitro, the antimicrobial agent taurolidine inhibited virtually all of the bacteria tested, including vanco- mycin-resistant enterococci, oxacillin-resistant staphylococci, and Stenotrophomonas maltophilia, at concentra- tions between 250 and 2,000 mg\\/ml. Taurolidine was not effective in experimental endocarditis. While it appears unlikely that this antimicrobial would be useful for systemic therapy, its bactericidal activity and the resistance rates found (<1029) are

C. Torres-Viera; C. Thauvin-Eliopoulos; M. Souli; P. DeGirolami; M. G. Farris; C. B. Wennersten; R. D. Sofia; G. M. Eliopoulos

2000-01-01

116

Application method affects the distribution and efficacy of rhizobacteria suppressive of downy brome ( Bromus tectorum)  

Microsoft Academic Search

Rhizobacteria that are capable of suppressing plant growth in a species-specific manner have potential as bioherbicides. Three bacterial strains, Pseudomonas putida strain FH160, Stenotrophomonas maltophilia strain FH131, and Enterobacter taylorae strain FH650, have been reported to suppress the growth of downy brome (Bromus tectorum L.). These strains were evaluated in the greenhouse using various application methods for the ability to

Mark Mazzola; Phillip W. Stahlman; Jan E. Leach

1995-01-01

117

Isolation of bacteria able to grow on both polyethylene glycol (PEG) and polypropylene glycol (PPG) and their PEG\\/PPG dehydrogenases  

Microsoft Academic Search

Two bacterial consortia growing on a random copolymer of ethylene glycol and propylene glycol units were obtained by enrichment\\u000a cultures from various microbial samples. Six major strains included in both consortia were purified and identified as Sphingomonads,\\u000a Pseudomonas sp. and Stenotrophomonas maltophilia. Three of them (Sphingobium sp. strain EK-1, Sphingopyxis macrogoltabida strain EY-1, and Pseudomonas sp. strain PE-2) utilized both

Xiaoping Hu; Akira Fukutani; Xin Liu; Kazuhide Kimbara; Fusako Kawai

2007-01-01

118

Effect of uracil on pullulan production by Aureobasidium pullulans CGMCC1234.  

PubMed

Effect of uracil on the pullulan production, biomass and uridine phosphorylase (UPase) activity was studied in this research. Uracil was found to enhance pullulan accumulation and the addition time of uracil was crucial to pullulan production. Pullulan yield of 49.07 g/L was achieved by adding 5mM uracil at 48 h, by comparison to 37.72 g/L obtained with the control. UPase activity could not be detected at early growth stage of Aureobasidium pullulans, but stimulated by added uracil at logarithmic phase and stationary phase. The time course study on the fermentation of pullulan demonstrates that pullulan production was not closely associated with biomass accumulation. Results indicate that the increased pullulan yield brought by uracil was correlated with UPase activity. PMID:24299794

Sheng, Long; Zhu, Guilan; Tong, Qunyi

2014-01-30

119

Identification and discrimination of bacteria using Fourier transform infrared spectroscopy  

NASA Astrophysics Data System (ADS)

Bacterial spectra were obtained in the wavenumber range of 4000-600 cm-1 using FTIR spectroscopy. FTIR spectral patterns were analyzed and matched with 16S-rRNA signatures of bacterial strains OS1 and OS2, isolated from oil sludge. Specific spectral bands obtained from OS1 (FJ226761), reference strain Bacillus flexus (ATCC 49095), OS2 (FJ215874) and reference strain Stenotrophomonas maltophilia (ATCC 19861) respectively, suggested that OS1 and ATCC 49095 were closely related whereas OS2 was different. The bands probably represent groups of proteins and lipids of specific bacteria. Separate peaks found in B. flexus were similar to those of OS1. The S. maltophilia (ATCC 19861) and OS2 exhibited a similar peak at 3272 cm-1. Amide bands (I, II and III) exhibited that OS1 and B. flexus were closely related, but were different from OS2. In the fingerprint region, peak at 1096 cm-1 and 1360 cm-1 exhibited the specific fingerprints of OS2 and reference strain S. maltophilia (ATCC 19861), respectively. The specific fingerprint signature was found at 1339 cm-1 for OS1 and at 1382 cm-1 for B. flexus ATCC 49095, allowing these two strains of B. flexus to be differentiated. This spectral signature originated from phospholipid and RNA components of the cell. Principle components analysis (PCA) of spectral regions exhibited with distinct sample clusters between Bacillus flexus (ATCC 49095), S. maltophilia (ATCC 19861), OS1 and OS2 in amide and fingerprint region.

Maity, Jyoti Prakash; Kar, Sandeep; Lin, Chao-Ming; Chen, Chen-Yen; Chang, Young-Fo; Jean, Jiin-Shuh; Kulp, Thomas R.

2013-12-01

120

16S rRNA gene-based identification of cultured bacterial flora from host-seeking Ixodes ricinus, Dermacentor reticulatus and Haemaphysalis concinna ticks, vectors of vertebrate pathogens.  

PubMed

A total of 151 bacterial isolates were recovered from different developmental stages (larvae, nymphs and adults) of field-collected ticks (67 strains from Ixodes ricinus, 38 from Dermacentor reticulatus, 46 from Haemaphysalis concinna). Microorganisms were identified by means of 16S rRNA gene sequencing. Almost 87 % of the strains belonged to G(+) bacteria with predominantly occurring genera Bacillus and Paenibacillus. Other G(+) strains included Arthrobacter, Corynebacterium, Frigoribacterium, Kocuria, Microbacterium, Micrococcus, Plantibacter, Rhodococcus, Rothia, and Staphylococcus. G(-) strains occurred less frequently, comprising genera Advenella, Pseudomonas, Rahnella, Stenotrophomonas, and Xanthomonas. Several strains of medical importance were found, namely Advenella incenata, Corynebacterium aurimucosum, Microbacterium oxydans, M. schleiferi, Staphylococcus spp., and Stenotrophomonas maltophilia. Data on cultivable microbial diversity in Eurasian tick species D. reticulatus and H. concinna are given, along with the extension of present knowledge concerning bacterial flora of I. ricinus. PMID:19937215

Rudolf, I; Mendel, J; Sikutov, S; Svec, P; Masarkov, J; Novkov, D; Bunkov, L; Sedlcek, I; Hublek, Z

2009-09-01

121

Antibiotic-resistant gram-negative bacterial infections in patients with cancer.  

PubMed

Patients with cancer are at high risk for infections caused by antibiotic resistant gram-negative bacteria. In this review, we summarize trends among the major pathogens and clinical syndromes associated with antibiotic resistant gram-negative bacterial infection in patients with malignancy, with special attention to carbapenem and expanded-spectrum ?-lactam resistance in Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia--all major threats to our cancer patients. Optimal therapy for these antibiotic-resistant pathogens still remains to be determined. PMID:25352627

Perez, Federico; Adachi, Javier; Bonomo, Robert A

2014-11-15

122

Q-PCR based bioburden assessment of drinking water throughout treatment and delivery to the International Space Station  

NASA Technical Reports Server (NTRS)

Previous studies indicated evidence of opportunistic pathogens samples obtained during missions to the International Space Station (ISS). This study utilized TaqMan quantitative PCR to determine specific gene abundance in potable and non-potable ISS waters. Probe and primer sets specific to the small subunit rRNA genes were used to elucidate overall bacterial rRNA gene numbers. while those specific for Burkholderia cepacia and Stenotrophomonas maltophilia were optimized and used to probe for the presence of these two opportunistic pathogens. This research builds upon previous microbial diversity studies of ISS water and demonstrates the utility of Q-PCR tool to examine water quality.

Newcombe, David; Stuecker, Tara; La Duc, Myron; Venkateswaran, Kasthuri

2005-01-01

123

Prevention of Biofilm Colonization by Gram-Negative Bacteria on Minocycline-Rifampin-Impregnated Catheters Sequentially Coated with Chlorhexidine  

PubMed Central

Resistant Gram-negative bacteria are increasing central-line-associated bloodstream infection threats. To better combat this, chlorhexidine (CHX) was added to minocycline-rifampin (M/R) catheters. The in vitro antimicrobial activity of CHX-M/R catheters against multidrug resistant, Gram-negative Acinetobacter baumannii, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia was tested. M/R and CHX-silver sulfadiazine (CHX/SS) catheters were used as comparators. The novel CHX-M/R catheters were significantly more effective (P < 0.0001) than CHX/SS or M/R catheters in preventing biofilm colonization and showed better antimicrobial durability. PMID:24165191

Jamal, Mohamed A.; Rosenblatt, Joel S.; Hachem, Ray Y.; Ying, Jiang; Pravinkumar, Egbert; Nates, Joseph L.; Chaftari, Anne-Marie P.

2014-01-01

124

Prevention of biofilm colonization by Gram-negative bacteria on minocycline-rifampin-impregnated catheters sequentially coated with chlorhexidine.  

PubMed

Resistant Gram-negative bacteria are increasing central-line-associated bloodstream infection threats. To better combat this, chlorhexidine (CHX) was added to minocycline-rifampin (M/R) catheters. The in vitro antimicrobial activity of CHX-M/R catheters against multidrug resistant, Gram-negative Acinetobacter baumannii, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia was tested. M/R and CHX-silver sulfadiazine (CHX/SS) catheters were used as comparators. The novel CHX-M/R catheters were significantly more effective (P < 0.0001) than CHX/SS or M/R catheters in preventing biofilm colonization and showed better antimicrobial durability. PMID:24165191

Jamal, Mohamed A; Rosenblatt, Joel S; Hachem, Ray Y; Ying, Jiang; Pravinkumar, Egbert; Nates, Joseph L; Chaftari, Anne-Marie P; Raad, Issam I

2014-01-01

125

Degradation of multiwall carbon nanotubes by bacteria.  

PubMed

Understanding the environmental transformation of multiwall carbon nanotubes (MWCNTs) is important to their life cycle assessment and potential environmental impacts. We report that a bacterial community is capable of degrading (14)C-labeled MWCNTs into (14)CO2 in the presence of an external carbon source via co-metabolism. Multiple intermediate products were detected, and genotypic characterization revealed three possible microbial degraders: Burkholderia kururiensis, Delftia acidovorans, and Stenotrophomonas maltophilia. This result suggests that microbe/MWCNTs interaction may impact the long-term fate of MWCNTs. PMID:23859846

Zhang, Liwen; Petersen, Elijah J; Habteselassie, Mussie Y; Mao, Liang; Huang, Qingguo

2013-10-01

126

Use of 16S rRNA Gene Sequencing for Identification of Nonfermenting Gram-Negative Bacilli Recovered from Patients Attending a Single Cystic Fibrosis Center  

PubMed Central

During 1999, we used partial 16S rRNA gene sequencing for the prospective identification of atypical nonfermenting gram-negative bacilli isolated from patients attending our cystic fibrosis center. Of 1,093 isolates of nonfermenting gram-negative bacilli recovered from 148 patients, 46 (4.2%) gave problematic results with conventional phenotypic tests. These 46 isolates were genotypically identified as Pseudomonas aeruginosa (19 isolates, 12 patients), Achromobacter xylosoxidans (10 isolates, 8 patients), Stenotrophomonas maltophilia (9 isolates, 9 patients), Burkholderia cepacia genomovar I/III (3 isolates, 3 patients), Burkholderia vietnamiensis (1 isolate), Burkholderia gladioli (1 isolate), and Ralstonia mannitolilytica (3 isolates, 2 patients), a recently recognized species. PMID:12354883

Ferroni, Agnes; Sermet-Gaudelus, Isabelle; Abachin, Eric; Quesne, Gilles; Lenoir, Gerard; Berche, Patrick; Gaillard, Jean-Louis

2002-01-01

127

Non-fermentative gram-negative bacteria in hospital tap water and water used for haemodialysis and bronchoscope flushing: prevalence and distribution of antibiotic resistant strains.  

PubMed

This study provides a detailed description of the distribution of non-fermentative gram-negative bacteria (NFGNB) collected in water sources (tap water and water used for haemodialysis and bronchoscope flushing) from different wards of a tertiary care hospital. The aim is to identify risk practices for patients or to alert clinicians to the possible contamination of environment and medical devices. The resistance profile of NFGNB environmental isolates has shown that more than half (55.56%) of the strains isolated were resistant to one or more antibiotics tested in different antimicrobial categories. In particular, 38.89% of these strains were multidrug resistant (MDR) and 16.67% were extensively drug resistant (XDR). The most prevalent bacterial species recovered in water samples were Pseudomonas aeruginosa, Pseudomonas fluorescens, Ralstonia pickettii and Stenotrophomonas maltophilia. Analysis of antibiotic resistance rates has shown remarkable differences between Pseudomonadaceae (P. aeruginosa and P. fluorescens) and emerging pathogens, such as S. maltophilia and R. pickettii. Multidrug resistance can be relatively common among nosocomial isolates of P. aeruginosa, which represent the large majority of clinical isolates; moreover, our findings highlight that the emergent antibiotic resistant opportunistic pathogens, such as R. pickettii and S. maltophilia, isolated from hospital environments could be potentially more dangerous than other more known waterborne pathogens, if not subjected to surveillance to direct the decontamination procedures. PMID:25173861

Vincenti, Sara; Quaranta, Gianluigi; De Meo, Concetta; Bruno, Stefania; Ficarra, Maria Giovanna; Carovillano, Serena; Ricciardi, Walter; Laurenti, Patrizia

2014-11-15

128

Systemic exposure to Pseudomonal bacteria: a potential link between type 1 diabetes and chronic inflammation.  

PubMed

Bacterial endotoxins have been associated with chronic inflammation and the development and progression of diabetic nephropathy. We hypothesized that subjects with high serum lipopolysaccharide activity also carry remains of bacterial DNA in their system. Serum-derived bacterial DNA clones were isolated and identified from 10 healthy controls and 14 patients with type 1 diabetes (T1D) using universal primers targeted to bacterial 16S rDNA. A total of 240 clones representing 35 unique bacterial species were isolated and identified. A significant proportion of the isolated bacteria could be assigned to our living environment. Proteobacteria was by far the most prevalent phylum among the samples. Notably, the patients had significantly higher frequencies of Stenotrophomonas maltophilia clones in their sera compared to the healthy controls. Real-time PCR analysis of S. maltophilia and Pseudomonas aeruginosa flagellin gene copy number in the human leukocyte DNA fraction revealed that the overall Pseudomonal bacterial load was higher in older patients with T1D. Serum IgA- and IgG-antibody levels against Pseudomonal bacteria Delftia acidovorans, P. aeruginosa, and S. maltophilia were also determined in 200 healthy controls and 200 patients with T1D. The patients had significantly higher serum levels of IgA antibodies against all three Pseudomonal bacteria. Additionally, the IgA antibodies against Pseudomonal bacteria correlated significantly with serum C-reactive protein. These findings indicate that recurrent or chronic Pseudomonal exposure may increase susceptibility to chronic inflammation in patients with T1D. PMID:22864910

Perneva, Lina; Fogarty, Christopher L; Pussinen, Pirkko J; Forsblom, Carol; Groop, Per-Henrik; Lehto, Markku

2013-06-01

129

Rhizosphere-induced selenium precipitation for possible applications in phytoremediation of se polluted effluents.  

PubMed

Two bacterial isolates were obtained in axenic culture from the rhizosphere soil of Astragalus bisulcatus, a legume able to hyperaccumulate selenium. Both strains resulted of particular interest for their high resistance to the toxic oxyanion SeO3(2-) (selenite, Se(IV)). On the basis of molecular and biochemical analyses, these two isolates were attributed to the species Bacillus mycoides and Stenotrophomonas maltophilia, respectively. Their capability in axenic culture to precipitate the soluble, bioavailable and highly toxic selenium form selenite to insoluble and relatively non-toxic Se(0) (elemental selenium) was evaluated in defined medium added with 0.2 or 0.5 mM Se(IV). Both strains showed to completely reduce 0.2 mM selenite in 120 h, while 0.5 mM Se(IV) was reduced up to 67% of the initial concentration by B. mycoides and to about 50% by S. maltophilia in 48 h. Together in a dual consortium, B. mycoides and S. maltophilia increased the kinetics of selenite reduction, thus improving the efficiency of the process. A model system for selenium rhizofiltration based on plant-rhizobacteria interactions has been proposed. PMID:15948605

Vallini, Giovanni; Di Gregorio, Simona; Lampis, Silvia

2005-01-01

130

Cloning of ?-1,3-1,4-glucanase gene from Bacillus licheniformis EGW039 (CGMCC 0635) and its expression in Escherichia coli BL21 (DE3)  

Microsoft Academic Search

?-1,3-1,4-Glucanase has been applied in the brewing and animal feed additive industry. It can effectively improve digestibility of barley-based diets and reduce enteritis. It also reduces viscosity during mashing for high-quality brewers malt. The aim of this work is to clone ?-1,3-1,4-glucanase-encoding gene and express it heterogeneously. The gene was amplified by polymerase chain reaction using Bacillus licheniformis genomic DNA

Da Teng; Jian-hua Wang; Ying Fan; Ya-lin Yang; Zi-gang Tian; Jin Luo; Guan-pin Yang; Fan Zhang

2006-01-01

131

Potency and Spectrum of Activity of AN3365, a Novel Boron-Containing Protein Synthesis Inhibitor, Tested against Clinical Isolates of Enterobacteriaceae and Nonfermentative Gram-Negative Bacilli  

PubMed Central

AN3365 (MIC50/90, 0.5/1 ?g/ml) was active against Enterobacteriaceae, including a subset of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae strains (MIC50/90, 1/2 ?g/ml). AN3365 inhibited 98.0 and 92.2% of wild-type (MIC50/90, 2/8 ?g/ml) and carbapenem-resistant (MIC50/90, 4/8 ?g/ml) Pseudomonas aeruginosa strains, respectively, at ?8 ?g/ml. AN3365 also demonstrated activity against wild-type Acinetobacter baumannii (MIC50/90, 2/8 ?g/ml) and Stenotrophomonas maltophilia (MIC50/90, 2/4 ?g/ml), while it was less active against multidrug-resistant A. baumannii (MIC50/90, 8/16 ?g/ml) and Burkholderia cepacia (MIC50/90, 8/32 ?g/ml). PMID:23507283

Alley, M. R. K.; Sader, Helio S.; Biedenbach, Douglas J.; Jones, Ronald N.

2013-01-01

132

An evaluation of microbial and chemical contamination sources related to the deterioration of tap water quality in the household water supply system.  

PubMed

The predominant microorganisms in samples taken from shower heads in residences in the Korean city "N" were Stenotrophomonas maltophilia, Sphingomonas paucimobilis, Acidovorax temperans, and Microbacterium lacticum. Legionella was not detected in this case. The volatile organic compounds (VOCs) vinylacetate, NN-DMA, cis-1,2-dichloroethylene, epichlorohydrin, and styrene were measured in five types of plastic pipes: PVC, PB, PP, PE, and cPVC. The rate of multiplication of the heterotrophic plate count (HPC) attached on the copper pipe in contact with hot tap water was higher than the rate for the copper pipe in contact with cold tap water. Biofilm accumulation on stainless steel pipes with added acetate (3 mg/L) was 2.56 times higher than the non-supplemented condition. Therefore, the growth of HPC in the pipe system was affected by the type and availability of nutrients and depended on variables such as heating during the hot water supply. PMID:24018837

Lee, Yoonjin

2013-09-01

133

An Evaluation of Microbial and Chemical Contamination Sources Related to the Deterioration of Tap Water Quality in the Household Water Supply System  

PubMed Central

The predominant microorganisms in samples taken from shower heads in residences in the Korean city N were Stenotrophomonas maltophilia, Sphingomonas paucimobilis, Acidovorax temperans, and Microbacterium lacticum. Legionella was not detected in this case. The volatile organic compounds (VOCs) vinylacetate, NN-DMA, cis-1,2-dichloroethylene, epichlorohydrin, and styrene were measured in five types of plastic pipes: PVC, PB, PP, PE, and cPVC. The rate of multiplication of the heterotrophic plate count (HPC) attached on the copper pipe in contact with hot tap water was higher than the rate for the copper pipe in contact with cold tap water. Biofilm accumulation on stainless steel pipes with added acetate (3 mg/L) was 2.56 times higher than the non-supplemented condition. Therefore, the growth of HPC in the pipe system was affected by the type and availability of nutrients and depended on variables such as heating during the hot water supply. PMID:24018837

Lee, Yoonjin

2013-01-01

134

Diversity of auxin-producing bacteria associated to Pseudomonas savastanoi -induced olive knots.  

PubMed

Forty three strains were isolated from knots induced by Pseudomonas savastanoi in different olive cultivars. All the selected bacteria were shown to produce variable amounts of the plant growth hormone indole-3-acetic acid (IAA). Amplification of the intergenic transcribed spacers (ITS) between 16S and 23S rDNA genes, allowed the clustering of the isolates into seven distinct groups. All isolates from ITS group 1 were positive to the Pseudomonas savastanoi pv. savastanoi specific iaa L gene as shown by PCR. Partial sequencing of 16S rDNA gene confirmed the identity of these isolates to Pseudomonas savastanoi strains and allowed to tentatively assign the other isolates from the remaining ITS groups to Pantoea oleae/agglomerans, Burkholderia cepacia, Pseudomonas putida, Stenotrophomonas maltophilia and Hafnia alvei. Identification of endophytic knot-derived isolates revealed association of various saprophytic and putative human pathogenic bacteria with P. savastanoi pv. savastanoi in knot environment of olive infected trees. PMID:18759227

Ouzari, Hadda; Khsairi, Amel; Raddadi, Noura; Jaoua, Leila; Hassen, Abdennaceur; Zarrouk, Mokhtar; Daffonchio, Daniele; Boudabous, Abdellatif

2008-10-01

135

The influence of bioaugmentation and biosurfactant addition on bioremediation efficiency of diesel-oil contaminated soil: feasibility during field studies.  

PubMed

The study focused on assessing the influence of bioaugmentation and addition of rhamnolipids on diesel oil biodegradation efficiency during field studies. Initial laboratory studies (measurement of emitted CO2 and dehydrogenase activity) were carried out in order to select the consortium for bioaugmentation as well as to evaluate the most appropriate concentration of rhamnolipids. The selected consortium consisted of following bacterial taxa: Aeromonas hydrophila, Alcaligenes xylosoxidans, Gordonia sp., Pseudomonas fluorescens, Pseudomonas putida, Rhodococcus equi, Stenotrophomonas maltophilia, Xanthomonas sp. It was established that the application of rhamnolipids at 150mg/kg of soil was most appropriate in terms of dehydrogenase activity. Based on the obtained results, four treatment methods were designed and tested during 365 days of field studies: I) natural attenuation; II) addition of rhamnolipids; III) bioaugmentation; IV) bioaugmentation and addition of rhamnolipids. It was observed that bioaugmentation contributed to the highest diesel oil biodegradation efficiency, whereas the addition of rhamnolipids did not notably influence the treatment process. PMID:24291585

Szulc, Alicja; Ambro?ewicz, Damian; Sydow, Mateusz; ?awniczak, ?ukasz; Piotrowska-Cyplik, Agnieszka; Marecik, Roman; Chrzanowski, ?ukasz

2014-01-01

136

Evaluation of the Colorimetric VITEK 2 Card for Identification of Gram-Negative Nonfermentative Rods: Comparison to 16S rRNA Gene Sequencing?  

PubMed Central

Ninety strains of a collection of well-identified clinical isolates of gram-negative nonfermentative rods collected over a period of 5 years were evaluated using the new colorimetric VITEK 2 card. The VITEK 2 colorimetric system identified 53 (59%) of the isolates to the species level and 9 (10%) to the genus level; 28 (31%) isolates were misidentified. An algorithm combining the colorimetric VITEK 2 card and 16S rRNA gene sequencing for adequate identification of gram-negative nonfermentative rods was developed. According to this algorithm, any identification by the colorimetric VITEK 2 card other than Achromobacter xylosoxidans, Acinetobacter sp., Burkholderia cepacia complex, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia should be subjected to 16S rRNA gene sequencing when accurate identification of nonfermentative rods is of concern. PMID:17507509

Zbinden, A.; Bttger, E. C.; Bosshard, P. P.; Zbinden, R.

2007-01-01

137

Dynamics of Seed-Borne Rice Endophytes on Early Plant Growth Stages  

PubMed Central

Bacterial endophytes are ubiquitous to virtually all terrestrial plants. With the increasing appreciation of studies that unravel the mutualistic interactions between plant and microbes, we increasingly value the beneficial functions of endophytes that improve plant growth and development. However, still little is known on the source of established endophytes as well as on how plants select specific microbial communities to establish associations. Here, we used cultivation-dependent and -independent approaches to assess the endophytic bacterrial community of surface-sterilized rice seeds, encompassing two consecutive rice generations. We isolated members of nine bacterial genera. In particular, organisms affiliated with Stenotrophomonas maltophilia and Ochrobactrum spp. were isolated from both seed generations. PCR-based denaturing gradient gel electrophoresis (PCR-DGGE) of seed-extracted DNA revealed that approximately 45% of the bacterial community from the first seed generation was found in the second generation as well. In addition, we set up a greenhouse experiment to investigate abiotic and biotic factors influencing the endophytic bacterial community structure. PCR-DGGE profiles performed with DNA extracted from different plant parts showed that soil type is a major effector of the bacterial endophytes. Rice plants cultivated in neutral-pH soil favoured the growth of seed-borne Pseudomonas oryzihabitans and Rhizobium radiobacter, whereas Enterobacter-like and Dyella ginsengisoli were dominant in plants cultivated in low-pH soil. The seed-borne Stenotrophomonas maltophilia was the only conspicuous bacterial endophyte found in plants cultivated in both soils. Several members of the endophytic community originating from seeds were observed in the rhizosphere and surrounding soils. Their impact on the soil community is further discussed. PMID:22363438

Hardoim, Pablo R.; Hardoim, Cristiane C. P.; van Overbeek, Leonard S.; van Elsas, Jan Dirk

2012-01-01

138

Sec- and Tat-Dependent Translocation of ?-Lactamases across the Escherichia coli Inner Membrane?  

PubMed Central

?-Lactamases represent the major resistance mechanism of gram-negative bacteria against ?-lactam antibiotics. The amino acid sequences of these proteins vary widely, but all are located in the periplasm of bacteria. In this study, we investigated the translocation mechanism of representative ?-lactamases in an Escherichia coli model. N-terminal signal sequence analyses, antibiotic activity assay, and direct measurement of translocation of a green fluorescent protein (GFP) reporter fused to ?-lactamases revealed that most were exported via the Sec pathway. However, the Stenotrophomonas maltophilia L2 ?-lactamase was exported via the E. coli Tat translocase, while the S. maltophilia L1 ?-lactamase was Sec dependent. These results show the possible Tat-dependent translocation of ?-lactamases in the E. coli model system. In addition, the mutation of the cytoskeleton-encoding gene mreB, which may be involved in the spatial organization of penicillin-binding proteins, decreased the MIC of ?-lactams for ?-lactamase-producing E. coli. These findings provide new knowledge about ?-lactamase translocation, a putative new target for addressing ?-lactamase-mediated resistance. PMID:18981261

Pradel, N.; Delmas, J.; Wu, L. F.; Santini, C. L.; Bonnet, R.

2009-01-01

139

Complementary treatment of contact lens-induced corneal ulcer using honey: a case report.  

PubMed

The aim of this study was to report the complementary use of honey for treatment of a contact lens-induced corneal ulcer. A 23-year-old contact lens user presented with a corneal ulcer in her left eye. She had visual acuity reduced to hand movement. There was a history of wearing contact lenses while swimming in a lake seven days before presentation. The cultures from corneal scrapings and contact lenses were positive for Klebsiella oxytoca, Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Pseudomonas spp. The treatment with topical levofloxacin and 25% (w/v) ?-irradiated honeydew honey solution was effective and the patient achieved final best corrected visual acuity of affected eye. In addition to positive clinical outcome, honeydew honey was shown to be highly effective in vitro against ocular isolates, in particular S. maltophilia. The minimal inhibitory concentrations for honeydew honey ranged from 5% to 10%. These results demonstrate that honey is a promising antibacterial agent in management of corneal ulcers. Moreover, honey exhibits anti-biofilm and anti-inflammatory properties, and thus becomes an interesting ophthalmologic agent. PMID:25278429

Majtanova, Nora; Vodrazkova, Erika; Kurilova, Veronika; Horniackova, Miroslava; Cernak, Martin; Cernak, Andrej; Majtan, Juraj

2015-02-01

140

Effects of pathology dyes on Raman bone spectra  

NASA Astrophysics Data System (ADS)

We report an overlooked source of artifacts for clinical specimens, where unexpected and normally negligible contaminants can skew the interpretation of results. During an ongoing study of bone fragments from diabetic osteomyelitis, strong Raman signatures were found, which did not correspond with normal bone mineral or matrix. In a bone biopsy from the calcaneus of a patient affected by diabetic osteomyelitis, Raman microspectroscopic analysis revealed regions with both abnormal mineral and degraded collagen in addition to normal bone. Additional bands indicated a pathological material. Stenotrophomonas maltophilia was identified in the wound culture by independent microbiologic examination. We initially assigned the unusual bands to xanthomonadin, a bacterial pigment from S. maltophilia. However, the same bands were also found more than a year later on a second specimen that had been noticeably contaminated with pathology marking dye. Drop deposition/Raman spectroscopy of commonly used pathology dyes revealed that a blue tissue-marking dye was responsible for the unusual bands in both specimens, even in the first specimen where there was no visible evidence of contamination.

Esmonde-White, Karen A.; Esmonde-White, Francis W. L.; Morris, Michael D.; Roessler, Blake J.

2013-05-01

141

Mir space station bacteria responses to modeled reduced gravity under starvation conditions  

NASA Astrophysics Data System (ADS)

Isolates from the Mir space station identified as Pseudomonas sp. and Stenotrophomonas maltophilia were subjected to clinorotation to model reduced gravity conditions in water in slow turning lateral vessels (STLVs). To examine cells in varying physiological states, bacteria were enumerated based on the Live/Dead BacLight kit, DAPI (4',6-diamidino-2-phenylindole) staining, fluorescent in situ hybridization (FISH), and colony forming units (CFU). Both Pseudomonas sp. and S. maltophilia showed a slight increase in abundance over time but only cells of Pseudomonas sp. were affected by modeled reduced gravity. For Pseudomonas sp. numbers of DAPI stained cells were significantly higher under modeled reduced gravity compared to normal gravity. In addition, the abundance of cells attached to stainless steel disks, on one sampling date, was greater for the Pseudomonas isolate under modeled reduced gravity than normal gravity. The isolates examined did not appear to appreciably enter into a viable, but not culturable state during the experiments. In general, differences between treatments were not great, demonstrating that responses to reduced gravity are less apparent under starvation conditions, compared to earlier studies which used more rich nutrient sources.

Baker, Paul W.; Leff, Laura G.

2006-01-01

142

[Phenotypic and genotypic characteristics of non fermenting atypical strains recovered from cystic fibrosis patients].  

PubMed

We used partial 16S rRNA gene (16S DNA) sequencing for the prospective identification of nonfermenting Gram-negative bacilli recovered from patients attending our cystic fibrosis center (hpital Necker-Enfants malades), which gave problematic results with conventional phenotypic tests. During 1999, we recovered 1093 isolates of nonfermenting Gram-negative bacilli from 702 sputum sampled from 148 patients. Forty-six of these isolates (27 patients) were not identified satisfactorily in routine laboratory tests. These isolates were identified by 16S DNA sequencing as Pseudomonas aeruginosa (19 isolates, 12 patients), Achromobacter xylosoxidans (10 isolates, 8 patients), Stenotrophomonas maltophilia (9 isolates, 9 patients), Burkholderia cepacia genomovar I/III (3 isolates, 3 patients), Burkholderia vietnamiensis (1 isolate), Burkholderia gladioli (1 isolate) and Ralstonia mannitolilytica (3 isolates, 2 patients). Fifteen isolates (33%) were resistant to all antibiotics in routine testing. Sixteen isolates (39%) resistant to colistin were recovered on B. cepacia-selective medium: 2 P. aeruginosa, 3 A. xylosoxidans, 3 S. maltophilia and the 8 Burkholderia--Ralstonia isolates. The API 20NE system gave no identification for 35 isolates and misidentified 11 isolates (2 P. aeruginosa, 2 A. xylosoxidans and 1 S. maltophilia classified as B. cepacia ). Control measures and/or treatment were clearly improved as a result of 16S DNA sequencing in three of these cases. This study confirms the weakness of phenotypic methods for identification of atypical nonfermenting Gram-negative bacilli recovered from cystic fibrosis patients. The genotypic methods, such as 16S DNA sequencing which allows identification of strains in routine practice, appears to have a small, but significant impact on the clinical management of CF patients. PMID:12948761

Ferroni, A; Sermet-Gaudelus, I; Abachin, E; Quesnes, G; Lenoir, G; Berche, P; Gaillard, J L

2003-09-01

143

Degradation and mineralization of high-molecular-weight polycyclic aromatic hydrocarbons by defined fungal-bacterial cocultures  

SciTech Connect

This study investigated the biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) in liquid media and soil by bacteria (Stenotrophomonas maltophilia VUN 10,010 and bacterial consortium VUN 10,009) and a fungus (Penicillium janthinellum VUO 10,201) that were isolated from separate creosote- and manufactured-gas plant-contaminated soils. The bacteria could use pyrene as their sole carbon and energy source in a basal salts medium (BSM) and mineralized significant amounts of benzo[a]pyrene cometabolically when pyrene was also present in BSM. P. janthinellum VUO 10,201 could not utilize any high-molecular-weight PAH as sole carbon and energy source but could partially degrade these if cultured in a nutrient broth. Although small amounts of chrysene, benz[a]pyrene, and dibenz[a,h]anthracene were degraded by axenic cultures of these isolates in BSM containing a single PAH, such conditions did not support significant microbial growth or PAH mineralization. However, significant degradation of, and microbial growth on, pyrene, chrysene, benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene, each as a single PAH in BSM, occurred when P. janthinellum VUO 10,201 and either bacterial consortium VUN 10,009 or S. maltophilia VUN 10,010 were combined in the one culture, i.e., fungal-bacterial cocultures: 25% of the benzo[a]pyrene was mineralized to CO{sub 2} by these cocultures over 49 days, accompanied by transient accumulation and disappearance of intermediates detected by high-pressure liquid chromatography. Inoculation of fungal-bacterial cocultures into PAH-contaminated soil resulted in significantly improved degradation of high-molecular-weight PAHs, benzo[a]pyrene mineralization, and reduction in the mutagenicity of organic soil extracts, compared with the indigenous microbes and soil amended with only axenic inocula.

Boonchan, S.; Britz, M.L.; Stanley, G.A.

2000-03-01

144

Specific and Rapid Detection by Fluorescent In Situ Hybridization of Bacteria in Clinical Samples Obtained from Cystic Fibrosis Patients  

PubMed Central

We report on the rapid and specific detection of bacteria commonly isolated from clinical specimens from cystic fibrosis (CF) patients by fluorescent in situ hybridization (FISH). On the basis of comparative sequence analysis, we designed oligonucleotide probes complementary to species-specific 16S rRNA regions of these microorganisms and demonstrated the specificities of the probes by hybridization of different remotely related as well as closely related reference strains. Furthermore, in a pilot project we investigated 75 sputum samples and 10 throat swab specimens from CF patients by FISH and detected Pseudomonas aeruginosa, Burkholderia cepacia, Stenotrophomonas maltophilia, Haemophilus influenzae, and Staphylococcus aureus within these specimens. The specificity of FISH was 100% in comparison to the results of conventional microbial culture. In contrast, the sensitivity of standard laboratory cultivation was moderately higher, since the limit for microscopic detection of bacteria within sputum samples by FISH was approximately 4 105 CFU/ml of sputum (resulting in a 90% sensitivity for FISH). Moreover, we demonstrated that FISH will be useful for the rapid detection of bacteria that cause acute pulmonary exacerbations in CF patients, as demonstrated in patients with H. influenzae, S. aureus, and P. aeruginosa exacerbations. Therefore, FISH is a valuable additional method for the rapid and specific detection of bacteria in clinical samples from CF patients, in particular, patients with pulmonary exacerbations. PMID:10655391

Hogardt, Michael; Trebesius, Karlheinz; Geiger, Anna M.; Hornef, Mathias; Rosenecker, Josef; Heesemann, Jrgen

2000-01-01

145

Multi-Channel Microfluidic Biosensor Platform Applied for Online Monitoring and Screening of Biofilm Formation and Activity  

PubMed Central

Bacterial colonization of surfaces and interfaces has a major impact on various areas including biotechnology, medicine, food industries, and water technologies. In most of these areas biofilm development has a strong impact on hygiene situations, product quality, and process efficacies. In consequence, biofilm manipulation and prevention is a fundamental issue to avoid adverse impacts. For such scenario online, non-destructive biofilm monitoring systems become important in many technical and industrial applications. This study reports such a system in form of a microfluidic sensor platform based on the combination of electrical impedance spectroscopy and amperometric current measurement, which allows sensitive online measurement of biofilm formation and activity. A total number of 12 parallel fluidic channels enable real-time online screening of various biofilms formed by different Pseudomonas aeruginosa and Stenotrophomonas maltophilia strains and complex mixed population biofilms. Experiments using disinfectant and antibiofilm reagents demonstrate that the biofilm sensor is able to discriminate between inactivation/killing of bacteria and destabilization of biofilm structures. The impedance and amperometric sensor data demonstrated the high dynamics of biofilms as a consequence of distinct responses to chemical treatment strategies. Gene expression of flagellar and fimbrial genes of biofilms grown inside the microfluidic system supported the detected biofilm growth kinetics. Thus, the presented biosensor platform is a qualified tool for assessing biofilm formation in specific environments and for evaluating the effectiveness of antibiofilm treatment strategies. PMID:25706987

Bruchmann, Julia; Sachsenheimer, Kai; Rapp, Bastian E.; Schwartz, Thomas

2015-01-01

146

Characterizing Novel Thermophilic Amylase Producing Bacteria From Taptapani Hot Spring, Odisha, India  

PubMed Central

Background: Amylases play a vital role in biotechnological studies and rank an important position in the world enzyme market (25% to 33%). Bioprocess method of amylase production is more effective than the other sources, since the technique is easy, cost effective, fast, and the enzymes of required properties can be procured. Objectives: The current study aimed to report the characteristics of novel amylase producing bacterial strains isolated from Taptapani hot spring, Odisha, India. Materials and Methods: Bacterial strains were isolated by dilution plating method from the water samples collected from Taptapani Hot Spring, Odisha and screened for amylase production through starch hydrolysis. The bacterial isolates were identified morphologically, biochemically, and finally by 16S rDNA profiling. Results: Based on the morphological, physiological, biochemical characteristics and the molecular characterization, the isolates SS1, SS2, and SS3 were identified as Bacillus barbaricus, Aeromonas veroni, and Stenotrophomonas maltophilia, respectively. The approximate molecular weight of enzymes from SS1, SS2, and SS3 strains were 19 kDa, 56 kDa and 49 kDa, respectively. Conclusions: The current report isolates, characterizes, and demonstrates the novel heat-adapted amylase-producing bacteria SS1, SS2 and SS3 from Taptapani hot spring, indicating its potentiality and stability under acidic conditions. PMID:25741425

Sen, Sudip Kumar; Raut, Sangeeta; Satpathy, Soumya; Rout, Prangya Ranjan; Bandyopadhyay, Bidyut; Das Mohapatra, Pradeep Kumar

2014-01-01

147

The Disinfecting Potential of Contact Lens Soutions used by Sultan Qaboos University Students  

PubMed Central

Objectives: This study aimed to determine the disinfecting potential of some contact lens solutions used by some university students in Oman. Methods: This work was carried out from January to June 2010 in the Department of Microbiology & Immunology, College of Medicine and Health Sciences, Sultan Qaboos University, Oman. Fifty disinfecting solutions, in which contact lenses were disinfected according to the manufacturers instructions, were collected from the students and plated on various microbiological culture media. Bacterial isolates were identified by API-20E, API-20NE and Phoenix automated systems while fungi were identified by their cultural characteristics and biochemistry. Results: From 98 isolates, Pseudomonas aeruginosa was 23.5%; Penicillium, 13%; Candida species, 9.2%; coagulase negative staphylococci, 9.2%; Serratia marcescens, 6.1%; Bacillus, 5.1%; Aspergillus flavus, 5.1%; Serratia liquefaciens, Pseudomonas fluorescens, Enterobacter cloacae and Aspergillus niger, 4.1% each; Chryseomonas luteola and Chryseomonas indologenes, 3.1% each; Stenotrophomonas maltophilia, Serratia odorifera, 2.0% each; Enterobacter aerogenes and Klebsiella pneumoniae, 1% each. Most isolates (65%) came from polyhexanide containing solutions. Conclusion: Contact lens disinfecting solutions with the same formulations, but manufactured by different companies, possessed different disinfecting potentials. PMID:21969898

Nzeako, B. C.; Al-Sumri, Sara H.

2011-01-01

148

Nonfermenting Gram-negative Bacilli other than Pseudomonas aeruginosa and Acinetobacter Spp. Causing Respiratory Tract Infections in a Tertiary Care Center  

PubMed Central

Background: Nonfermenting gram-negative bacilli have emerged as important healthcare-associated pathogens. It is important to correctly identify all clinically significant nonfermenting gram-negative bacilli considering the intrinsic multidrug resistance exhibited by these bacteria. Materials and Methods: A retrospective study was undertaken to identify the various nonfermenting gram-negative bacilli other than Pseudomonas aeruginosa and Acinetobacter spp. isolated from respiratory samples (n = 9363), to understand their clinical relevance and to analyze their antibiotic susceptibility pattern. Results: Nonfermenting gram-negative bacilli were isolated from 830 (16.4%) samples showing significant growth. Thirty-three (4%) isolates constituted nonfermenting gram-negative bacilli other than P. aeruginosa and Acinetobacter spp. Stenotrophomonas maltophilia (15, 45.5%) was the most common isolate followed by Burkholderia cepacia (4, 12.1%), Sphingomonas paucimobilis (3, 9.1%), and Achromobacter xylosoxidans (3, 9.1%). On the basis of clinicomicrobiological correlation, pathogenicity was observed in 69.7% (n = 23) isolates. Timely and correct treatment resulted in clinical improvement in 87.9% cases. Conclusion: Any nonfermenting gram-negative bacilli isolated from respiratory tract infection should not be ignored as mere contaminant, but correlated clinically for its pathogenic potential and identified using standard methods so as to institute appropriate and timely antibiotic coverage. PMID:24672175

Chawla, Kiran; Vishwanath, Shashidhar; Munim, Frenil C

2013-01-01

149

Comparative studies on toluene removal and pressure drop in biofilters using different packing materials.  

PubMed

To select the best available packing material for malodorous organic gases such as toluene and benzene, biofilter performance was compared in biofilters employed different packing materials including porous ceramic (celite), Jeju scoria (lava), a mixture of granular activated carbon (GAC) and celite (GAC/celite), and cubic polyurethane foam (PU). A toluene-degrading bacterium, Stenotrophomonas maltophilia T3-c, was used as the inoculum. The maximum elimination capacities in the celite, lava, and GAC/celite biofilters were 100, 130, and 110 gm(-3) hr(-1), respectively. The elimination capacity for the PU biofilter was approximately 350 g m(-3) hr(-1) at an inlet loading of approximately 430 g m(-3) hr(-1), which was 2 to 3.5 times higher than for the other biofilters. The pressure drop gradually increased in the GAC/ celite, celite and lava biofilters after 23 day due to bacterial over-growth, and the toluene removal efficiency remarkably decreased with increasing pressure drop. Backwashing method was not effective for the control of biomass in these biofilters. In the PU biofilter however, backwashing allowed maintenance of a pressure drop of 1 to 3 mm H2O m(-1) and a removal efficiency of > 80%, indicating that the PU was the best packing material for toluene removal among the packing materials tested. PMID:21047004

Ryu, Hee Wook; Kim, So Jung; Cho, Kyung Suk

2010-05-01

150

Antimicrobial activity of novel nanostructured Cu-SiO2 coatings prepared by chemical vapour deposition against hospital related pathogens  

PubMed Central

There is increasing recognition that the healthcare environment acts as an important reservoir for transmission of healthcare acquired infections (HCAI). One method of reducing environmental contamination would be use of antimicrobial materials. The antimicrobial activity of thin silica-copper films prepared by chemical vapour deposition was evaluated against standard strains of bacteria used for disinfectant testing and bacteria of current interest in HCAI. The structure of the coatings was determined using Scanning Electron Microscopy and their hardness and adhesion to the substrate determined. Antimicrobial activity was tested using a method based on BS ISO 22196:2007. The coatings had a pale green-brown colour and had a similar hardness to steel. SEM showed nano-structured aggregates of Cu within a silica matrix. A log10 reduction in viability of >5 could be obtained within 4h for the disinfectant test strains and within 6h for producing Acinetobacter baumannii, Klebsiella pneumoniae and Stenotrophomonas maltophilia. Activity against the other hospital isolates was slower but still gave log10 reduction factors of >5 for extended spectrum ?-lactamase producing Escherichia coli and >3 for vancomycin resistant Enterococcus faecium, methicillin resistant Staphylococcus aureus and Pseudomonas aeruginosa within 24h. The results demonstrate the importance of testing antimicrobial materials destined for healthcare use against isolates of current interest in hospitals as well as standard test strains. The coatings used here can also be applied to substrates such as metals and ceramics and have potential applications where reduction of microbial environmental contamination is desirable. PMID:24007899

2013-01-01

151

Effects of the joint exposure of decabromodiphenyl ether and tetrabromobisphenol A on soil bacterial community structure.  

PubMed

Decabromodiphenyl ether (BDE209) and tetrabromobisphenol A (TBBPA) are the main contaminants at electronic waste (e-waste) recycling sites (EWRSs), and their potential toxicological effects have received extensive attention. However, the impact on soil microorganism of joint exposure to the two chemicals remains almost unknown. Therefore, indoor incubation tests were performed on control and contaminated soil samples to determine the response of soil bacterial community structure in the joint presence of BDE209 and TBBPA for the first time. The results have demonstrated that the soil bacterial diversity generally declined with increasing BDE209 and TBBPA concentrations and moderate and high doses of both chemicals can cause inhibitory effects. PCR-DGGE analysis indicated that the correlations between Shannon-Weaver index and contaminant concentrations could be well represented by a second-order polynomial model. The combined toxicity of the two chemicals was antagonistic during the first 14 days and then synergistic. Pectobacterium carotovorum, Sinorhizobium fredii HH103, and Stenotrophomonas maltophilia were highly tolerant to joint exposure during the entire incubation period. Moreover, some Staphylococcus strains were enriched after 90 days exposed to TBBPA or low concentrations of BDE209, indicating that they might degrade the two chemicals effectively. The results of these observations have provided some basic understanding of potential ecological effects of joint exposure to BDE209 and TBBPA on soil microorganism at EWRSs. PMID:25106514

Zhang, Wei; Chen, Lei; An, Shuai; Liu, Kou; Lin, Kuangfei; Fu, Rongbing

2015-01-01

152

Diaryl-substituted azolylthioacetamides: Inhibitor discovery of New Delhi metallo-?-lactamase-1 (NDM-1).  

PubMed

The emergence and spread of antibiotic-resistant pathogens is a global public health problem. Metallo-?-lactamases (M?Ls) such as New Delhi M?L-1 (NDM-1) are principle contributors to the emergence of resistance because of their ability to hydrolyze almost all known ?-lactam antibiotics including penicillins, cephalosporins, and carbapenems. A clinical inhibitor of MBLs has not yet been found. In this study we developed eighteen new diaryl-substituted azolylthioacetamides and found all of them to be inhibitors of the M?L L1 from Stenotrophomonas maltophilia (Ki < 2 ?M), thirteen to be mixed inhibitors of NDM-1 (Ki < 7 ?M), and four to be broad-spectrum inhibitors of all four tested M?Ls CcrA from Bacteroides fragilis, NDM-1 and ImiS from Aeromonas veronii, and L1 (Ki < 52 ?M), which are representative of the B1a, B1b, B2, and B3 subclasses, respectively. Docking studies revealed that the azolylthioacetamides, which have the broadest inhibitory activity, coordinate to the Zn(II) ion(s) preferentially via the triazole moiety, while other moieties interact mostly with the conserved active site residues Lys224 (CcrA, NDM-1, and ImiS) or Ser221 (L1). PMID:25048031

Zhang, Yi-Lin; Yang, Ke-Wu; Zhou, Ya-Jun; LaCuran, Alecander E; Oelschlaeger, Peter; Crowder, Michael W

2014-11-01

153

Isolation of Vermamoeba vermiformis and associated bacteria in hospital water.  

PubMed

To detect new potential pathogens in hospital water, we isolated free-living amoebae in water samples taken from three different hospitals in Marseille (France). The samples were inoculated in media containing saline buffer and various bacteria as nutrient sources. The isolated amoebae were identified by gene sequencing. Among the 105 water samples, taken from 19 sites, we isolated 14 amoebae, of which 9 Vermamoeba vermiformis and 5 Acanthamoeba sp. None of the amoebae showed the presence of obligate bacterial endosymbionts. Because V.vermiformis was most commonly isolated, we used an axenic collection strain to isolate amoeba-resistant bacteria from the same sites. The isolated bacterial species included Stenotrophomonas maltophilia and Legionella sp. Legionella taurinensis was isolated for the first time in association with amoebae. A strict intracellular bacterium was isolated, that may represent a new genus among the Chlamydiales. We propose that it be named "Candidatus Rubidus massiliensis". Our study shows that the isolation and identification of new pathogens associated with amoebae, which were previously performed using Acanthamoeba sp., should instead use V.vermiformis because this organism is more commonly associated with humans and is an essential complement of Acanthamoeba sp. co-culture to study the ecology of hospital water supplies. PMID:25697664

Pagnier, Isabelle; Valles, Camille; Raoult, Didier; La Scola, Bernard

2015-03-01

154

Bacterial degradation of naproxen--undisclosed pollutant in the environment.  

PubMed

The presence of non-steroidal anti-inflammatory drugs (NSAIDs) in the environment is an emerging problem due to their potential influence on human health and biocenosis. This is the first report on the biotransformation of naproxen, a polycyclic NSAID, by a bacterial strain. Stenotrophomonas maltophilia KB2 transformed naproxen within 35 days with about 28% degradation efficiency. Under cometabolic conditions with glucose or phenol as a carbon source degradation efficiency was 78% and 40%, respectively. Moreover, in the presence of naproxen phenol monooxygenase, naphthalene dioxygenase, hydroxyquinol 1,2-dioxygenase and gentisate 1,2-dioxygenase were induced. This suggests that degradation of naproxen occurs by its hydroxylation to 5,7,8-trihydroxynaproxen, an intermediate that can be cleaved by hydroxyquinol 1,2-dioxygenase. The cleavage product is probably further oxidatively cleaved by gentisate 1,2-dioxygenase. The obtained results provide the basis for the use of cometabolic systems in the bioremediation of polycyclic NSAID-contaminated environments. PMID:25026371

Wojcieszy?ska, Danuta; Domaradzka, Dorota; Hupert-Kocurek, Katarzyna; Guzik, Urszula

2014-12-01

155

Pyrene removal and transformation by joint application of alfalfa and exogenous microorganisms and their influence on soil microbial community.  

PubMed

Phytoremediation is an attractive approach for the cleanup of polycyclic aromatic hydrocarbons-contaminated soil. The joint effect of alfalfa and microorganisms, including Arthrobacter oxydans, Staphylococcus auricularis and Stenotrophomonas maltophilia, on pyrene removal was investigated. The results showed that the joint effect primarily contributed to pyrene removal, and the concentration of residual pyrene in rhizosphere soil was lower than that in non-rhizosphere soil. After joint treatment for 45d, pyrene in rhizosphere soils decreased from 11.3, 52.5 and 106.0mg/kg to 2.0-3.0, 15.0-18.7, and 41.2-44.8mg/kg, respectively. These bacteria significantly enhanced pyrene accumulation and microbial community diversity, and increased soil dehydrogenase and polyphenol oxidase activities. Pyrene was initially degraded through ring cleavage. One of the main metabolites 4-dihydroxy-phenanthrene was transformed into naphthol and 1,2-dihydroxynaphthalene, which were further degraded through salicylic acid pathway and phthalic acid pathway, separately. PMID:25232990

Ye, Jinshao; Yin, Hua; Peng, Hui; Bai, Jieqiong; Li, Yuepeng

2014-12-01

156

Microbial Surveillance of Potable Water Sources of the International Space Station  

NASA Technical Reports Server (NTRS)

To mitigate risk to the crew, the microbial surveillance of the quality of potable water sources of the International Space Station (ISS) has been ongoing since before the arrival of the first permanent crew. These water sources have included stored ground-supplied water, water produced by the shuttle fuel cells during flight, and ISS humidity condensate that is reclaimed and processed. Monitoring was accomplished using a self-contained filter designed to allow bacterial growth and enumeration during flight. Upon return to earth, microbial isolates were identified using 16S ribosomal gene sequencing. While the predominant isolates were common Gramnegative bacteria including Ralstonia eutropha, Methylobacterium fujisawaense, and Spingomonas paucimobilis, opportunistic pathogens such as Stenotrophomonas maltophilia and Pseudomonas aeruginosa were also isolated. Results of in-flight enumeration have indicated a fluctuation of bacterial counts above system design specifications. Additional in-flight monitoring capability for the specific detection of coliforms was added in 2004; no coliforms have been detected from any potable water source. Neither the bacterial concentrations nor the identification of the isolates recovered from these samples has suggested a threat to crew health.

Bruce, Rebekah J.; Ott, C. Mark; Skuratov, Vladimir M.; Pierson, Duane L.

2005-01-01

157

Multi-channel microfluidic biosensor platform applied for online monitoring and screening of biofilm formation and activity.  

PubMed

Bacterial colonization of surfaces and interfaces has a major impact on various areas including biotechnology, medicine, food industries, and water technologies. In most of these areas biofilm development has a strong impact on hygiene situations, product quality, and process efficacies. In consequence, biofilm manipulation and prevention is a fundamental issue to avoid adverse impacts. For such scenario online, non-destructive biofilm monitoring systems become important in many technical and industrial applications. This study reports such a system in form of a microfluidic sensor platform based on the combination of electrical impedance spectroscopy and amperometric current measurement, which allows sensitive online measurement of biofilm formation and activity. A total number of 12 parallel fluidic channels enable real-time online screening of various biofilms formed by different Pseudomonas aeruginosa and Stenotrophomonas maltophilia strains and complex mixed population biofilms. Experiments using disinfectant and antibiofilm reagents demonstrate that the biofilm sensor is able to discriminate between inactivation/killing of bacteria and destabilization of biofilm structures. The impedance and amperometric sensor data demonstrated the high dynamics of biofilms as a consequence of distinct responses to chemical treatment strategies. Gene expression of flagellar and fimbrial genes of biofilms grown inside the microfluidic system supported the detected biofilm growth kinetics. Thus, the presented biosensor platform is a qualified tool for assessing biofilm formation in specific environments and for evaluating the effectiveness of antibiofilm treatment strategies. PMID:25706987

Bruchmann, Julia; Sachsenheimer, Kai; Rapp, Bastian E; Schwartz, Thomas

2015-01-01

158

Real-time monitoring of hydrogen cyanide (HCN) and ammonia (NH?) emitted by Pseudomonas aeruginosa.  

PubMed

We present the real-time monitoring of hydrogen cyanide (HCN) production from Pseudomonas aeruginosa (P. aeruginosa) strains in vitro, using laser-based photoacoustic spectroscopy. Simultaneously, the production of ammonia (NH3) was measured, and the influence of different factors (e.g. the medium, temperature and antibiotics treatment) was assessed. Both reference strains and clinical isolates of patients with CF were studied, and compared to other pathogens commonly present in lungs/airways of CF patients. Hydrogen cyanide production starts to rise as soon as P. aeruginosa bacteria reach the stationary phase ((9.0-9.5) 10(9) colony forming units, CFUs), up to concentrations of 14.5 microliters per hour (l?h(-1)). Different strains of P. aeruginosa produced HCN to varying degrees, and addition of tobramycin strongly reduced HCN production within 2?h from application. Burkholderia cepacia also produced HCN (up to 0.35l?h(-1) in 9.0? ?10(9)?CFU) while other pathogens (Aspergillus fumigatus, Stenotrophomonas maltophilia, Mycobacterium abscessus) did not produce detectable levels. Our study reveals for the first time a broad overview of the dynamics of the HCN production in vitro. PMID:25634638

Neerincx, Anne H; Mandon, Julien; van Ingen, Jakko; Arslanov, Denis D; Mouton, Johan W; Harren, Frans J M; Merkus, Peter J F M; Cristescu, Simona M

2015-06-01

159

Decontamination effects of low-temperature plasma generated by corona discharge. Part II: new insights.  

PubMed

The second part of our paper presents the results of experiments with the decontamination of surfaces by low-temperature plasma generated by corona discharge in air at atmospheric pressure. A simple device is described and the effects of the corona discharge on model microorganisms, viz. the yeast Candida albicans, Gram-negative bacteria Escherichia coli, Enterobacter aerogenes, Neisseria sicca, Stenotrophomonas maltophilia, Gram-positive bacteria Deinococcus radiodurans, Enterococcus faecium, Staphylococcus epidermidis, Streptococcus sanguinis, and vegetative and spore forms of Geobacillus stearothermophilus are discussed. A similar microbicidal effect after about one-minute exposure was observed in all vegetative forms of the microorganisms. Measurement in growth inhibition zones on a semisolid medium was used to determine the dependence of the microbicidal effect on exposure time and the distance between electrodes. Counting of colonies served to assess the microbicidal effect of the discharge on contaminated inert surfaces observable after more than 1 min exposure. Geobacillus stearothermophilus spores were found to have several times lower susceptibility to the action of the discharge and the microbicidal effect was observed only after an 8 min exposure. Reaction with the iodide reagent did not unambiguously demonstrate the difference between ozone and singlet oxygen as presumed active components of the corona. The area distribution of reactive oxygen species was determined; it was found to differ from the Wartburg law depending on exposure time. Qualitative evidence was obtained on the penetration of the reactive oxygen species into the semisolid medium. PMID:18225640

Scholtz, V; Julk, J; Krha, V; Mosinger, J; Kopeck, S

2007-01-01

160

Rosmarinic Acid from Eelgrass Shows Nematicidal and Antibacterial Activities against Pine Wood Nematode and Its Carrying Bacteria  

PubMed Central

Pine wilt disease (PWD), a destructive disease for pine trees, is caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus and additional bacteria. In this study, extracts of Zostera marina showed a high nematicidal activity against PWN and some of the bacteria that it carries. Light yellow crystals were obtained from extracts of Z. marina through solvent extraction, followed by chromatography on AB-8 resin and crystallization. The NMR and HPLC analysis showed that the isolated compound was rosmarinic acid (RosA). RosA showed effective nematicidal activity, of which the LC50 (50% lethal concentration) to PWN at 24 h, 48 h and 72 h was 1.18 mg/g, 1.05 mg/g and 0.95 mg/g, respectively. To get a high yield rate of RosA from Z. marina, single factor experiments and an L9 (34) orthogonal experiment were performed. This extraction process involved 70% ethanol for 3 h at 40 C. The extraction dosage was 1:50 (w/v). The highest yield of RosA from Zostera was 3.13 mg/g DW (dried weight). The crude extracts of Zostera marina (10 mg/mL) and RosA (1 mg/mL) also showed inhibitory effects to some bacterial strains carried by PWN: Klebsiella sp., Stenotrophomonas maltophilia, Streptomyces sp. and Pantoea agglomerans. The results of these studies provide clues for preparing pesticide to control PWD from Z. marina. PMID:23201594

Wang, Jingyu; Pan, Xueru; Han, Yi; Guo, Daosen; Guo, Qunqun; Li, Ronggui

2012-01-01

161

Characterization of contaminants from a sanitized milk processing plant.  

PubMed

Milk processing lines offer a wide variety of microenvironments where a diversity of microorganisms can proliferate. We sampled crevices and junctions where, due to deficient reach by typical sanitizing procedures, bacteria can survive and establish biofilms. The sampling sites were the holding cell, cold storage tank, pasteurizer and storage tank--transfer pump junction. The culturable bacteria that were isolated after the sanitation procedure were predominantly Pseudomonas spp., Serratia spp, Staphylococcus sciuri and Stenotrophomonas maltophilia. We assayed several phenotypic characteristics such as the ability to secrete enzymes and siderophores, as well as the capacity of the strains to form biofilms that might contribute to their survival in a mixed species environment. The Pseudomonas spp. isolates were found to either produce proteases or lecithinases at high levels. Interestingly, protease production showed an inverse correlation with siderophore production. Furthermore, all of the Serratia spp. isolates were strong biofilm formers and spoilage enzymes producers. The organisms identified were not mere contaminants, but also producers of proteins with the potential to lower the quality and shelf-life of milk. In addition, we found that a considerable number of the Serratia and Pseudomonas spp. isolated from the pasteurizer were capable of secreting compounds with antimicrobial properties. PMID:22761957

Cleto, Sara; Matos, Snia; Kluskens, Leon; Vieira, Maria Joo

2012-01-01

162

Antimicrobial activity and interference of tobramycin and chloramphenicol on bacterial adhesion to intraocular lenses.  

PubMed

The antimicrobial activities of tobramycin and chloramphenicol were evaluated by determining minimum inhibitory and bactericidal concentrations against Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, group A, group B and group G streptococci, Klebsiella spp., Stenotrophomonas maltophilia and ciprofloxacin-resistant and -susceptible Pseudomonas aeruginosa, as well as by evaluating interference on adhesion of slime producer strains of S. aureus and P. aeruginosa to intraocular lens from tobramycin and chloramphenicol pharmaceutical products by scanning electron microscopy. Chloramphenicol was more active against Gram-positive bacteria than was tobramycin, which instead showed higher activity against ciprofloxacin-susceptible P. aeruginosa. Treatment of lenses with the antimicrobial products eradicated the bacterial biofilm, which was already notably reduced after 5 min. This activity was more pronounced for chloramphenicol against S. aureus and for tobramycin against P. aeruginosa. Bacterial adhesion was also significantly reduced when lenses colonized by P. aeruginosa were treated with chloramphenicol, even if they were resistant to this drug. In conclusion, the tested drugs showed marked antibacterial activity, particularly by interfering with bacterial biofilms. The data obtained in this study suggest a specific use of chloramphenicol in topical prophylaxis aimed at avoiding bacterial contaminations. However, further specific in vivo studies are needed to confirm these data. PMID:12866361

Drago, L; De Vecchi, E; Nicola, L; Gismondo, M R

2003-01-01

163

Antibiotic Resistance and Extended-Spectrum ?-Lactamases in Isolated Bacteria from Seawater of Algiers Beaches (Algeria)  

PubMed Central

The aim of the study was to evaluate bacterial antibiotic resistance in seawater from four beaches in Algiers. The most significant resistance rates were observed for amoxicillin and ticarcillin, whereas they were relatively low for ceftazidime, cefotaxime and imipenem. According to sampling sites, the highest resistance rates were recorded for 2 sites subjected to chemical and microbiological inputs (amoxicillin, 43% and 52%; ticarcillin, 19.6% and 47.7%), and for 2 sites relatively preserved from anthropogenic influence, resistance rates were lowest (amoxicillin, 1.5% and 16%; ticarcillin, 0.8% and 2.6%). Thirty-four bacteria resistant to imipenem (n=14) or cefotaxime (n=20) were identified as Pseudomonas aeruginosa (n=15), Pseudomonas fluorescens(7), Stenotrophomonas maltophilia(4), Burkholderia cepacia(2), Bordetella sp. (1), Pantoea sp. (1), Acinetobacter baumannii(1), Chryseomonas luteola(1), Ochrobactrum anthropi(1) and Escherichia coli(1). Screening for extended spectrum ?-lactamase showed the presence of CTX-M-15 ?-lactamase in the E. coli isolate, and the encoding gene was transferable in association with the IncI1 plasmid of about 50 kbp. Insertion sequence ISEcp1B was located upstream of the CTX-M-15 gene. This work showed a significant level of resistance to antibiotics, mainly among environmental saprophytic bacteria. Transmissible CTX-M-15 was detected in E. coli; this may mean that contamination of the environment by resistant bacteria may cause the spread of resistance genes. PMID:22095134

Alouache, Souhila; Kada, Mohamed; Messai, Yamina; Estepa, Vanesa; Torres, Carmen; Bakour, Rabah

2012-01-01

164

Changes in gram negative microorganisms resistance pattern during 4?years period in a referral teaching hospital; a surveillance study  

PubMed Central

Background and purpose Surveillance studies evaluating antimicrobial susceptibilities are of great value in preventing the spread of resistant pathogens by elucidating the trend of resistance in commonly used antibiotics and as a consequence providing information for prescribing the most appropriate agent. This study is a longitudinal antimicrobial resistance surveillance study designed to evaluate the trend in antimicrobial resistance to gram negative microorganisms from 2007 to 2010. Method During a four-year period (20072010) isolates derived from all patients admitted to infectious diseases ward of Imam Khomeini Hospital, the major referral center for infectious disease in Iran with the highest admission rates, were evaluated. Based on disk diffusion method and zone of inhibition size, the microorganism was regarded as to be sensitive, resistant or has intermediate susceptibility to the antimicrobial agents. Results The widest spread Gram-negative microorganism in all of isolates taken together in our study was E.coli (30%) followed by Stenotrophomonas maltophilia in 28.6% and Enterobacter spp. in 11.9%, respectively. The susceptibility to amikacin, imipenem, piperacillin/tazobactam, and nitrofurantoin was equal or above 50% for all microorganisms over four years. However, the susceptibility to ampicillin, ampicillin/sulbactam, cefotaxim, and ceftriaxone was less than 50% in derived isolates during the study period. Conclusion In conclusion, the finding of the present study revealed that resistance rate to common antimicrobial agents in Iran is growing and isolates were susceptible mostly to broad-spectrum antibiotics including imipenem and piperacillin/tazobactam. PMID:23351308

2012-01-01

165

Rosmarinic acid from eelgrass shows nematicidal and antibacterial activities against pine wood nematode and its carrying bacteria.  

PubMed

Pine wilt disease (PWD), a destructive disease for pine trees, is caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus and additional bacteria. In this study, extracts of Zostera marina showed a high nematicidal activity against PWN and some of the bacteria that it carries. Light yellow crystals were obtained from extracts of Z. marina through solvent extraction, followed by chromatography on AB-8 resin and crystallization. The NMR and HPLC analysis showed that the isolated compound was rosmarinic acid (RosA). RosA showed effective nematicidal activity, of which the LC?? (50% lethal concentration) to PWN at 24 h, 48 h and 72 h was 1.18 mg/g, 1.05 mg/g and 0.95 mg/g, respectively. To get a high yield rate of RosA from Z. marina, single factor experiments and an L? (3?) orthogonal experiment were performed. This extraction process involved 70% ethanol for 3 h at 40 C. The extraction dosage was 1:50 (w/v). The highest yield of RosA from Zostera was 3.13 mg/g DW (dried weight). The crude extracts of Zostera marina (10 mg/mL) and RosA (1 mg/mL) also showed inhibitory effects to some bacterial strains carried by PWN: Klebsiella sp., Stenotrophomonas maltophilia, Streptomyces sp. and Pantoea agglomerans. The results of these studies provide clues for preparing pesticide to control PWD from Z. marina. PMID:23201594

Wang, Jingyu; Pan, Xueru; Han, Yi; Guo, Daosen; Guo, Qunqun; Li, Ronggui

2012-12-01

166

The role of wood-inhabiting bacteria in pine wilt disease.  

PubMed

The pathogenicity of the pine wood nematode (PWN), Bursaphelenchus xylophilus together with the bacteria isolated from black pine (Pinus thunbergii) bark inoculated to axenic black pine seedlings, significantly exceeded that of the axenic PWNs alone, demonstrating that the bacteria play an important role in pine wilt disease. Inoculation of seedlings with bacteria-free culture filtrates of the seven isolates from the dead seedlings from the above experiment showed that all isolate filtrates killed the seedlings within 8 days. Identification of the bacteria using 16S rDNA sequencing showed that the isolates belonged to strains By253Ydz-fq, S209, 210-50 and 210-50 in Bacillus and the DN1.1 strain of Stenotrophomonas maltophilia, respectively. Completing Koch's postulates using the seven bacterial isolates to inoculate pine seedlings showed that all the seedlings that received aseptic PWNs mixed with the seven bacterial isolates died within 18 days post inoculation, while those inoculated with 'wild' PWNs died 16 days post inoculation. No disease symptoms developed on seedlings that received sterile water or aseptic PWNs. The horizontal transfer of the pathogenic bacteria may explain differences in bacterial species carried by PWN in different geographic areas. PMID:23430766

Zhao, Bo Guang; Tao, Jian; Ju, Yun Wei; Wang, Peng Kai; Ye, Jian Ling

2011-09-01

167

Evaluation of pyrrolidonyl arylamidase for the identification of nonfermenting Gram-negative rods.  

PubMed

To evaluate the activity of pyrrolidonyl arylamidase (PYR) for the differentiation and identification of nonfermenting gram negative rods (NFGNR), 293 isolates were tested. A 24 h culture of each test organism was prepared. From this a 108-109 cfu/mL suspension was added to 0.25 mL of sterile physiologic solution. A PYR disk was then added and the test was incubated for 30 minutes at 35-37 degrees C, at environmental atmosphere. Reading was done by adding 1 drop of cinnamaldehyde reagent. Strains of Acinetobacter baumannii, Acinetobacter haemolyticus, Alcaligenes faecalis, Bergeyella zoohelcum, Bordetella bronchiseptica, Bordetella hinzii, Brevundimonas diminuta, Brevundimonas vesicularis, Brucella ovis, Brucella spp., Brucella suis, Burkholderia cepacia complex, Moraxella catarrhalis, Moraxella lacunata, Moraxella nonliquefaciens, Moraxella osloensis, Oligella ureolytica, Pseudomonas alcaligenes, Pseudomonas mendocina, Pseudomonas pseudoalcaligenes, Pseudomonas putida, Pseudomonas stutzeri, Pseudomonas Vb3, Psychrobacter phenylpyruvicus, and Stenotrophomonas maltophilia were PYR negative. On the other hand Achromobacter piechaudii, Achromobacter denitrificans, Achromobacter xylosoxidans, Burkholderia gladioli, Chryseobacterium gleum-indologenes, Comamonas testosroni, Cupriavidus pauculus, Delftia acidovorans, Elizabethkingia meningoseptica, Myroides spp., Ochrobactrum anthropi, Pseudomonas oryzihabitans, Ralstonia pickettii, Rhizobium radiobacter, Shewanella spp., Sphingobacterium multivorum, Sphingobacterium spiritivorum, and Weeksella virosa were PYR positive. Finally, Acinetobacter lwoffii, Pseudomonas aeruginosa, Pseudomonas fluorescens, Roseomonas spp., and Sphingomonas paucimobilis-parapaucimobilis were PYR variable. PYR testing should be considered as a useful tool to facilitate the identification of NFGNR. PMID:16822636

Bombicino, Karina A; Almuzara, Marisa N; Famiglietti, Angela M R; Vay, Carlos

2007-01-01

168

Capability of a selected bacterial consortium for degrading diesel/biodiesel blends (B20): enzyme and biosurfactant production.  

PubMed

The search for alternative sources of energy, such as biodiesel, has been stimulated, since this biofuel is highly susceptible for biodegradation and has low toxicity, thus, reducing the impact in ecosystems. The objective of this study was to select a bacterial consortium with potential for degrading diesel/biodiesel blends (B20) obtained from areas contaminated with hydrocarbons/esters. In order to evaluate the biodegrability of the blend, six enzyme assays were conducted: alkane hydroxylase, Catechol 1,2-dioxygenase, Catechol 2,3-dioxygenase, Protocatechol 3,4-dioxygenase, ?-NPA hydrolysis (esterase), and release of fatty acids through titration (lipase), with estimative of total protein and biosurfactant production (surface tension measurement and emulsifying index E(24)). The best results obtained allowed the selection of four bacteria isolates (Bacillus megaterium, Bacillus pumilus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia) for compiling a consortium, which will be used for bioaugmentation strategies in soils contaminated with these fuels. This consortium exhibited high potential for biodegradation of biodiesel, and might be an efficient alternative for cleaning up these contaminated environments. PMID:22755524

Meyer, Daniel Derrossi; Santestevan, Naiara Aguiar; Bcker, Francielle; Salamoni, Sabrina Pinto; Andreazza, Robson; De Oliveira Camargo, Flvio Anastcio; Bento, Ftima Menezes

2012-01-01

169

Preventing microbial colonisation of catheters: antimicrobial and antibiofilm activities of cellobiose dehydrogenase.  

PubMed

The ability of cellobiose dehydrogenase (CDH) to produce hydrogen peroxide (H(2)O(2)) for antimicrobial and antibiofilm functionalisation of urinary catheters was investigated. A recombinantly produced CDH from Myriococcum thermophilum was shown to completely inhibit the growth of Escherichia coli and Staphylococcus aureus both in liquid and solid media when supplemented with either 0.8 mM or 2 mM cellobiose as substrate. Biofilm formation on silicone films was prevented by CDH when supplemented with 1mM cellobiose. The CDH/cellobiose system also successfully inhibited many common urinary catheter-colonising micro-organisms, including multidrug-resistant S. aureus, Staphylococcus epidermidis, Proteus mirabilis, Stenotrophomonas maltophilia, Acinetobacter baumannii and Pseudomonas aeruginosa. Interestingly, CDH was also able to produce H(2)O(2) during oxidation of extracellular polysaccharides (exPS) formed by micro-organisms in the absence of cellobiose. The H(2)O(2) production and consequently antimicrobial and antibiofilm activities on these exPS were enhanced by incorporation of glycoside hydrolases such as amylases. Hydrolysis of polysaccharides by these enzymes increases the number of terminal reducing sugars as substrates for CDH as well as destabilises the biofilm. Furthermore, CDH suspended in catheter lubricants killed bacteria in biofilms colonising catheters. Incorporation of the CDH/cellobiose system in the lubricant therefore makes it an easy strategy for preventing microbial colonisation of catheters. PMID:25176584

Thallinger, Barbara; Argirova, Maya; Lesseva, Magdalena; Ludwig, Roland; Sygmund, Christoph; Schlick, Angelika; Nyanhongo, Gibson S; Guebitz, Georg M

2014-11-01

170

Host-Defense Peptides with Therapeutic Potential from Skin Secretions of Frogs from the Family Pipidae  

PubMed Central

Skin secretions from frogs belonging to the genera Xenopus, Silurana, Hymenochirus, and Pseudhymenochirus in the family Pipidae are a rich source of host-defense peptides with varying degrees of antimicrobial activities and cytotoxicities to mammalian cells. Magainin, peptide glycine-leucine-amide (PGLa), caerulein-precursor fragment (CPF), and xenopsin-precursor fragment (XPF) peptides have been isolated from norepinephrine-stimulated skin secretions from several species of Xenopus and Silurana. Hymenochirins and pseudhymenochirins have been isolated from Hymenochirus boettgeri and Pseudhymenochirus merlini. A major obstacle to the development of these peptides as anti-infective agents is their hemolytic activities against human erythrocytes. Analogs of the magainins, CPF peptides and hymenochirin-1B with increased antimicrobial potencies and low cytotoxicities have been developed that are active (MIC < 5 ?M) against multidrug-resistant clinical isolates of Staphylococcus aureus, Escherichia coli, Acinetobacter baumannii, Stenotrophomonas maltophilia and Klebsiella pneumoniae. Despite this, the therapeutic potential of frog skin peptides as anti-infective agents has not been realized so that alternative clinical applications as anti-cancer, anti-viral, anti-diabetic, or immunomodulatory drugs are being explored. PMID:24434793

Conlon, J. Michael; Mechkarska, Milena

2014-01-01

171

Characterization of Contaminants from a Sanitized Milk Processing Plant  

PubMed Central

Milk processing lines offer a wide variety of microenvironments where a diversity of microorganisms can proliferate. We sampled crevices and junctions where, due to deficient reach by typical sanitizing procedures, bacteria can survive and establish biofilms. The sampling sites were the holding cell, cold storage tank, pasteurizer and storage tank - transfer pump junction. The culturable bacteria that were isolated after the sanitation procedure were predominantly Pseudomonas spp., Serratia spp, Staphylococcus sciuri and Stenotrophomonas maltophilia. We assayed several phenotypic characteristics such as the ability to secrete enzymes and siderophores, as well as the capacity of the strains to form biofilms that might contribute to their survival in a mixed species environment. The Pseudomonas spp. isolates were found to either produce proteases or lecithinases at high levels. Interestingly, protease production showed an inverse correlation with siderophore production. Furthermore, all of the Serratia spp. isolates were strong biofilm formers and spoilage enzymes producers. The organisms identified were not mere contaminants, but also producers of proteins with the potential to lower the quality and shelf-life of milk. In addition, we found that a considerable number of the Serratia and Pseudomonas spp. isolated from the pasteurizer were capable of secreting compounds with antimicrobial properties. PMID:22761957

Cleto, Sara; Matos, Snia; Kluskens, Leon; Vieira, Maria Joo

2012-01-01

172

An 8-year survey of strains identified in blood cultures in a clinical haematology unit.  

PubMed

The aim of our study was to determine the epidemiological profile and the antibiotic susceptibility of bacteria and fungi identified from blood cultures in the patients of the clinical haematology unit. A retrospective study was carried out over an 8-year period (2003-2010) in the clinical haematology unit of the Percy Military Medical Center. During this period, we collected 723 isolates: Gram-negative bacilli (70.8%) and Gram-positive cocci (18.7%). The four most commonly isolated species were Escherichia coli (18.5%), Pseudomonas aeruginosa (14.8%), Stenotrophomonas maltophilia (6.2%) and Staphylococcus epidermidis (5.4%). The rate of methicillin-resistant Staphylococcus aureus was 6.45% and that of coagulase-negative staphylococci 61.2%. No resistance to glycopeptides was observed. In E. coli, as in the Klebsiella-Enterobacter-Serratia group, a 27% resistance to fluoroquinolones was observed. Concerning P. aeruginosa, the phenotypes were distributed over penicillinase (23.4%) and cephalosporinase (13.1% were resistant to ceftazidime). The impermeability rate of imipenem was 9.3%. The aggressiveness and duration of haematological treatments explains why infections remain one of the main complications of neutropenia. The emergence of new or unusual bacteria is highly likely. Antibiotic selective pressure and long periods of hospitalization could explain the emergence of multiresistant bacteria. As a consequence, epidemiological surveillance is indispensable. PMID:23826912

Bousquet, A; Malfuson, J-V; Sanmartin, N; Konopacki, J; MacNab, C; Souleau, B; de Revel, T; Elouennass, M; Samson, T; Soler, C; Foissaud, V; Martinaud, C

2014-01-01

173

Characterization of copper-resistant rhizosphere bacteria from Avena sativa and Plantago lanceolata for copper bioreduction and biosorption.  

PubMed

Copper is a toxic heavy metal widely used to microbial control especially in agriculture. Consequently, high concentrations of copper residues remain in soils selecting copper-resistant organisms. In vineyards, copper is routinely used for fungi control. This work was undertaken to study copper resistance by rhizosphere microorganisms from two plants (Avena sativa L. and Plantago lanceolata L.) common in vineyard soils. Eleven rhizosphere microorganisms were isolated, and four displayed high resistance to copper. The isolates were identified by 16S rRNA gene sequence analysis as Pseudomonas putida (A1), Stenotrophomonas maltophilia (A2) and Acinetobacter sp. (A6), isolated from Avena sativa rhizosphere, and Acinetobacter sp. (T5), isolated from Plantago lanceolata rhizosphere. The isolates displayed high copper resistance in the temperature range from 25C to 35C and pH in the range from 5.0 to 9.0. Pseudomonas putida A1 resisted as much as 1,000mgL(-1) of copper. The isolates showed similar behavior on copper removal from liquid medium, with a bioremoval rate of 30% at 500mgL(-1) after 24h of growth. Speciation of copper revealed high copper biotransformation, reducing Cu(II) to Cu(I), capacity. Results indicate that our isolates are potential agents for copper bioremoval and bacterial stimulation of copper biosorption by Avena sativa and Plantago lanceolata. PMID:22002857

Andreazza, Robson; Okeke, Benedict C; Pieniz, Simone; Camargo, Flvio A O

2012-04-01

174

Assessing the xylanolytic bacterial diversity during the malting process.  

PubMed

The presence of microorganisms producing cell wall hydrolyzing enzymes such as xylanases during malting can improve mash filtration behavior and consequently have potential for more efficient wort production. In this study, the xylanolytic bacterial community during malting was assessed by isolation and cultivation on growth media containing arabinoxylan, and identification by 16S rRNA gene sequencing. A total of 33 species-level operational taxonomic units (OTUs) were found, taking into account a 3% sequence dissimilarity cut-off, belonging to four phyla (Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria) and 25 genera. Predominant OTUs represented xylanolytic bacteria identified as Sphingobacterium multivorum, Stenotrophomonas maltophilia, Aeromonas hydrophila and Pseudomonas fulva. DNA fingerprinting of all xylanolytic isolates belonging to S. multivorum obtained in this study revealed shifts in S. multivorum populations during the process. Xylanase activity was determined for a selection of isolates, with Cellulomonas flavigena showing the highest activity. The xylanase of this species was isolated and purified 23.2-fold by ultrafiltration, 40% ammonium sulfate precipitation and DEAE-FF ion-exchange chromatography and appeared relatively thermostable. This study will enhance our understanding of the role of microorganisms in the barley germination process. In addition, this study may provide a basis for microflora management during malting. PMID:24010623

Malfliet, Sofie; Just, Annelies; Crauwels, Sam; Willems, Kris; De Cooman, Luc; Lievens, Bart; Aerts, Guido

2013-12-01

175

Biodegradation of phenanthrene in bioaugmented microcosm by consortium ASP developed from coastal sediment of Alang-Sosiya ship breaking yard.  

PubMed

A phenanthrene-degrading bacterial consortium (ASP) was developed using sediment from the Alang-Sosiya shipbreaking yard at Gujarat, India. 16S rRNA gene-based molecular analyses revealed that the bacterial consortium consisted of six bacterial strains: Bacillus sp. ASP1, Pseudomonas sp. ASP2, Stenotrophomonas maltophilia strain ASP3, Staphylococcus sp. ASP4, Geobacillus sp. ASP5 and Alcaligenes sp. ASP6. The consortium was able to degrade 300 ppm of phenanthrene and 1000 ppm of naphthalene within 120 h and 48 h, respectively. Tween 80 showed a positive effect on phenanthrene degradation. The consortium was able to consume maximum phenanthrene at the rate of 46 mg/h/l and degrade phenanthrene in the presence of other petroleum hydrocarbons. A microcosm study was conducted to test the consortium's bioremediation potential. Phenanthrene degradation increased from 61% to 94% in sediment bioaugmented with the consortium. Simultaneously, bacterial counts and dehydrogenase activities also increased in the bioaugmented sediment. These results suggest that microbial consortium bioaugmentation may be a promising technology for bioremediation. PMID:23906474

Patel, Vilas; Patel, Janki; Madamwar, Datta

2013-09-15

176

Investigation of bacterial pathogens on 70 frequently used environmental surfaces in a large urban U.S. university.  

PubMed

After reports of increased severity of bacterial infections from community institutions, a broad spectrum of 70 surfaces was sampled for potential bacterial pathogens in the morning and afternoon of one day per week over three consecutive weeks in a large U.S. university. Surfaces included public telephone mouthpieces, water fountain drains, student computer keyboards and desks, and buttons on elevators, vending machines, and photocopiers. A total of 420 samples was obtained. Bacterial counts were high on telephone mouthpieces, up to 168.8 colony-forming units (CFUs).cm(-2) of surface area. Stenotrophomonas maltophilia was isolated from 60% of fountain drains. Ninety percent of the keyboards showed positive bacterial cultures in the afternoon sampling. Staphylococcus aureus was identified on keyboards, telephone mouthpieces, and an elevator button. No S. aureus were methicillin-resistant. The swab sampling method reduced bacterial counts to less than or equal to 2.0 CFU.cm(-2) on keyboards and telephone mouthpieces. Disinfectants for possible use in cleaning of telephones, water fountain drains, and keyboards are discussed. PMID:19192740

Brooke, Joanna S; Annand, John W; Hammer, Angela; Dembkowski, Karen; Shulman, Stanford T

2009-01-01

177

Low Rates of Pseudomonas aeruginosa Misidentification in Isolates from Cystic Fibrosis Patients?  

PubMed Central

Pseudomonas aeruginosa is an important cause of pulmonary infection in cystic fibrosis (CF). Its correct identification ensures effective patient management and infection control strategies. However, little is known about how often CF sputum isolates are falsely identified as P. aeruginosa. We used P. aeruginosa-specific duplex real-time PCR assays to determine if 2,267 P. aeruginosa sputum isolates from 561 CF patients were correctly identified by 17 Australian clinical microbiology laboratories. Misidentified isolates underwent further phenotypic tests, amplified rRNA gene restriction analysis, and partial 16S rRNA gene sequence analysis. Participating laboratories were surveyed on how they identified P. aeruginosa from CF sputum. Overall, 2,214 (97.7%) isolates from 531 (94.7%) CF patients were correctly identified as P. aeruginosa. Further testing with the API 20NE kit correctly identified only 34 (59%) of the misidentified isolates. Twelve (40%) patients had previously grown the misidentified species in their sputum. Achromobacter xylosoxidans (n = 21), Stenotrophomonas maltophilia (n = 15), and Inquilinus limosus (n = 4) were the species most commonly misidentified as P. aeruginosa. Overall, there were very low rates of P. aeruginosa misidentification among isolates from a broad cross section of Australian CF patients. Additional improvements are possible by undertaking a culture history review, noting colonial morphology, and performing stringent oxidase, DNase, and colistin susceptibility testing for all presumptive P. aeruginosa isolates. Isolates exhibiting atypical phenotypic features should be evaluated further by additional phenotypic or genotypic identification techniques. PMID:19261796

Kidd, Timothy J.; Ramsay, Kay A.; Hu, Honghua; Bye, Peter T. P.; Elkins, Mark R.; Grimwood, Keith; Harbour, Colin; Marks, Guy B.; Nissen, Michael D.; Robinson, Philip J.; Rose, Barbara R.; Sloots, Theo P.; Wainwright, Claire E.; Bell, Scott C.

2009-01-01

178

Stent hypersensitivity and infection in sinus cavities  

PubMed Central

Persistent mucosal inflammation, granulation tissue formation, hypersensitivity, and multifactorial infection are newly described complications of retained drug-eluting stents from endoscopic sinus surgery for refractory rhinosinusitis. In an important report published in Allergy and Rhinology, a 45-year-old male patient suffering from recalcitrant chronic rhinosinusitis underwent functional endoscopic sinus surgery and was found, for the first time, to have steroid-eluting catheters that were inadvertently left in the ethmoid and frontal sinuses. The retained catheters had caused persistent mucosal inflammation and formation of granulation tissue denoting hypersensitivity reaction. These consequences had induced perpetuation of symptoms of chronic rhinosinusitis. Meticulous removal of the retained stents with the nitinol wings from inflamed tissues of the frontal, ethmoidal, and sphenoethmoidal recesses in which they were completely imbedded was successfully performed without polypoid regrowth. Cultures of specimens taken from both left and right stents showed heavy growth of Stenotrophomonas maltophilia and moderate growth of Klebsiella oxytoca, coagulase negative Staphylococcus, and beta-hemolytic Streptococcus anginosus. Fungal infection was not detected. The current knowledge and experience regarding stent hypersensitivity and infection in relation with the use of stents in sinus cavities is reviewed. PMID:24498522

Soufras, George D.; Hahalis, George

2013-01-01

179

Counterion-activated nanoactuator: reversibly switchable killing/releasing bacteria on polycation brushes.  

PubMed

A strategy to release attached bacteria from surface-grafted bactericidal poly((trimethylamino)ethyl methacrylate chloride) (pTMAEMA) brushes has been proposed. The pTMAEMA brushes were fabricated via the surface-initiated atom transfer radical polymerization for contact killing of bacteria, including Escherichia coli, Staphylococcus epidermidis and Stenotrophomonas maltophilia. The bacteria-conditioning surfaces, afterward, were washed with electrolyte solutions containing anions with different lipophilic characteristic, charge density, polarity and adsorbility to quaternary ammonium groups in polymers. Because of the special ion-pairing interactions, the interfacial properties, including wettability and ?-potential, can be manipulated in a controlled manner. Therefore, the counterion-assisted modulation of pTMAEMA brushes facilitates the bacterial release and regeneration of antimicrobial polymer films. The physicochemical properties of polymer brushes and their interactions with counterions were characterized using an ellipsometer, contact angle goniometer, X-ray photoelectron spectroscopy and an electrokinetic analyzer. The repetitive killing and releasing actions of pTMAEMA through unlocking and locking counterions were demonstrated, showing the robust effectiveness of the pTMAEMA-based nanoactuator in controlling the physical action by the chemical stimuli. The real-world implementation of the nanoactuator was demonstrated with a surgical scalpel by repelling killed bacteria and retaining reusability. PMID:25608105

Huang, Chun-Jen; Chen, Yen-Sheng; Chang, Yung

2015-02-01

180

Diversity and Antimicrobial Properties of Lactic Acid Bacteria Isolated from Rhizosphere of Olive Trees and Desert Truffles of Tunisia  

PubMed Central

A total of 119 lactic acid bacteria (LAB) were isolated, by culture-dependant method, from rhizosphere samples of olive trees and desert truffles and evaluated for different biotechnological properties. Using the variability of the intergenic spacer 16S-23S and 16S rRNA gene sequences, the isolates were identified as the genera Lactococcus, Pediococcus, Lactobacillus, Weissella, and Enterococcus. All the strains showed proteolytic activity with variable rates 42% were EPS producers, while only 10% showed the ability to grow in 9% NaCl. In addition, a low rate of antibiotic resistance was detected among rhizospheric enterococci. Furthermore, a strong antibacterial activity against plant and/or pathogenic bacteria of Stenotrophomonas maltophilia, Pantoea agglomerans, Pseudomonas savastanoi, the food-borne Staphylococcus aureus, and Listeria monocytogenes was recorded. Antifungal activity evaluation showed that Botrytis cinerea was the most inhibited fungus followed by Penicillium expansum, Verticillium dahliae, and Aspergillus niger. Most of the active strains belonged to the genera Enterococcus and Weissella. This study led to suggest that environmental-derived LAB strains could be selected for technological application to control pathogenic bacteria and to protect food safety from postharvest deleterious microbiota. PMID:24151598

Najjari, Afef; Turki, Yousra; Jaballah, Sana; Boudabous, Abdelatif; Ouzari, Hadda

2013-01-01

181

Newer antibacterial agents and their potential role in cystic fibrosis pulmonary exacerbation management.  

PubMed

Pulmonary exacerbations in cystic fibrosis (CF) are frequent events and account for a substantial proportion of the burden of morbidity and mortality in this disease. Antibacterial therapies to treat pulmonary exacerbations are instituted empirically and are individualized based on both patient factors (severity of exacerbation, frequency of exacerbation, recent courses of anti-infectives) and pathogen factors (previously isolated pathogens and in vitro predicted susceptibilities). However, the epidemiology of pathogens infecting CF airways is changing, with increased incidence of methicillin-resistant Staphylococcus aureus (MRSA), drug-resistant Pseudomonas aeruginosa and other Gram-negative non-fermenters such as Stenotrophomonas maltophilia and Achromobacter xylosoxidans. Accordingly, a great need for new and novel agents for the management of acute exacerbations in CF exists. While several antibiotics have recently been approved or are close to approval for clinical use, frequently their emphasis has been for Gram-positive, and specifically MRSA-related, disease. Despite this, these agents may have a role in CF-related exacerbations. This article reviews the spectrum of activity, pharmacokinetics and clinical and theoretical evidence for the use of newer agents including tigecycline, doripenem and ceftobiprole in the management of CF pulmonary exacerbations. Appropriate use of these agents in CF will require detailed CF-specific pharmacokinetic and pharmacodynamic data. PMID:20605846

Parkins, M D; Elborn, J S

2010-09-01

182

Anti-infective properties of epigallocatechin-3-gallate (EGCG), a component of green tea  

PubMed Central

The consumption of green tea (Camellia sinensis) has been shown to have many physiological and pharmacological health benefits. In the past two decades several studies have reported that epigallocatechin-3-gallate (EGCG), the main constituent of green tea, has anti-infective properties. Antiviral activities of EGCG with different modes of action have been demonstrated on diverse families of viruses, such as Retroviridae, Orthomyxoviridae and Flaviviridae and include important human pathogens like human immunodeficiency virus, influenza A virus and the hepatitis C virus. Furthermore, the molecule interferes with the replication cycle of DNA viruses like hepatitis B virus, herpes simplex virus and adenovirus. Most of these studies demonstrated antiviral properties within physiological concentrations of EGCG in vitro. In contrast, the minimum inhibitory concentrations against bacteria were 10100-fold higher. Nevertheless, the antibacterial effects of EGCG alone and in combination with different antibiotics have been intensively analysed against a number of bacteria including multidrug-resistant strains such as methicillin-resistant Staphylococcus aureus or Stenotrophomonas maltophilia. Furthermore, the catechin EGCG has antifungal activity against human-pathogenic yeasts like Candida albicans. Although the mechanistic effects of EGCG are not fully understood, there are results indicating that EGCG binds to lipid membranes and affects the folic acid metabolism of bacteria and fungi by inhibiting the cytoplasmic enzyme dihydrofolate reductase. This review summarizes the current knowledge and future perspectives on the antibacterial, antifungal and antiviral effects of the green tea constituent EGCG. PMID:23072320

Steinmann, J; Buer, J; Pietschmann, T; Steinmann, E

2013-01-01

183

Degradation and Mineralization of High-Molecular-Weight Polycyclic Aromatic Hydrocarbons by Defined Fungal-Bacterial Cocultures  

PubMed Central

This study investigated the biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) in liquid media and soil by bacteria (Stenotrophomonas maltophilia VUN 10,010 and bacterial consortium VUN 10,009) and a fungus (Penicillium janthinellum VUO 10,201) that were isolated from separate creosote- and manufactured-gas plant-contaminated soils. The bacteria could use pyrene as their sole carbon and energy source in a basal salts medium (BSM) and mineralized significant amounts of benzo[a]pyrene cometabolically when pyrene was also present in BSM. P. janthinellum VUO 10,201 could not utilize any high-molecular-weight PAH as sole carbon and energy source but could partially degrade these if cultured in a nutrient broth. Although small amounts of chrysene, benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene were degraded by axenic cultures of these isolates in BSM containing a single PAH, such conditions did not support significant microbial growth or PAH mineralization. However, significant degradation of, and microbial growth on, pyrene, chrysene, benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene, each as a single PAH in BSM, occurred when P. janthinellum VUO 10,201 and either bacterial consortium VUN 10,009 or S. maltophilia VUN 10,010 were combined in the one culture, i.e., fungal-bacterial cocultures: 25% of the benzo[a]pyrene was mineralized to CO2 by these cocultures over 49 days, accompanied by transient accumulation and disappearance of intermediates detected by high-pressure liquid chromatography. Inoculation of fungal-bacterial cocultures into PAH-contaminated soil resulted in significantly improved degradation of high-molecular-weight PAHs, benzo[a]pyrene mineralization (53% of added [14C]benzo[a]pyrene was recovered as 14CO2 in 100 days), and reduction in the mutagenicity of organic soil extracts, compared with the indigenous microbes and soil amended with only axenic inocula. PMID:10698765

Boonchan, Sudarat; Britz, Margaret L.; Stanley, Grant A.

2000-01-01

184

Specific and functional diversity of endophytic bacteria from pine wood nematode Bursaphelenchus xylophilus with different virulence.  

PubMed

Pine wilt disease (PWD) caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus, is one of the most devastating diseases of Pinus spp. The PWN was therefore listed as one of the most dangerous forest pests in China meriting quarantine. Virulence of the PWN is closely linked with the spread of PWD. However, main factors responsible for the virulence of PWNs are still unclear. Recently epiphytic bacteria carried by PWNs have drawn much attention. But little is known about the relationship between endophytic bacteria and virulence of B. xylophilus. In this research, virulence of ten strains of B. xylophilus from different geographical areas in six provinces of China and four pine species were tested with 2-year-old seedlings of Pinus thunbergii. Endophytic bacteria were isolated from PWNs with different virulence to investigate the relationship between the bacteria and PWN virulence. Meanwhile, the carbon metabolism of endophytic bacteria from highly and low virulent B. xylophilus was analyzed using Biolog plates (ECO). The results indicated that ten strains of PWNs showed a wide range of virulence. Simultaneously, endophytic bacteria were isolated from 90% of the B. xylophilus strains. The dominant endophytic bacteria in the nematodes were identified as species of Stenotrophomonas, Achromobacter, Ewingella, Leifsonia, Rhizobium, and Pseudomonas using molecular and biochemical methods. Moreover, S. maltophilia, and A. xylosoxidans subsp. xylosoxidans were the predominant strains. Most of the strains (80%) from P. massoniana contained either S. maltophilia, A. xylosoxidans, or both species. There was a difference between the abilities of the endophytic bacteria to utilize carbon sources. Endophytic bacteria from highly virulent B. xylophilus had a relatively high utilization rate of carbohydrate and carboxylic acids, while bacteria from low virulent B. xylophilus made better use of amino acids. In conclusion, endophytic bacteria widely exist in B. xylophilus from different pines and areas; and B. xylophilus strains with different virulence possessed various endophytic bacteria and diverse carbon metabolism which suggested that the endophytic bacteria species and carbon metabolism might be related with the B. xylophilus virulence. PMID:23289015

Wu, Xiao-Qin; Yuan, Wei-Min; Tian, Xiao-Jing; Fan, Ben; Fang, Xin; Ye, Jian-Ren; Ding, Xiao-Lei

2013-01-01

185

Weeds as a source of plant growth promoting rhizobacteria in agricultural soils.  

PubMed

The influence of plant growth promoting (PGP) activity of bacterial communities recovered from each of six weed species (barnyard grass (Echinochloa crusfalli (L.) Beauv.), corn spurrey (Spergula arvensis L.), goldenrod (Sonchus sp.), Italian ryegrass (Lolium multiflorum L.), lamb's-quarters (Chenopodium album L.), and quack grass (Agropyron repens (L.) Beauv.)) was examined in relation to the effect it had on the growth of the potato cultivar Russet Burbank. Bacterial species composition and community structure were compared, species-abundance relationships were determined, and those members conferring positive benefits for potato growth and development were identified. Of the genera identified, Bacillus, Arthrobacter, Stenotrophomonas, Acinetobacter, and Pseudomonas were the most common, and Stenotrophomonas maltophilia was the most frequent species recovered across all sources. Significantly higher population densities were found in the root zones of quack grass, compared with Italian ryegrass and lamb's-quarters. There were no significant differences in species richness among the root zones; however, evenness indices (species distribution) were significantly lower in corn spurrey (P = 0.05). Significantly higher diversity indices (Hill-1 and Hill-2 numbers) (P = 0.05) were found in the root zone soil communities of potato and goldenrod, indicating a decrease in the proportional abundance of common and very abundant species, respectively, while in barnyard grass, corn spurrey, and Italian ryegrass the reverse was the case. In both years of the study, Italian ryegrass and corn spurrey were consistently better sources of PGP rhizobacteria for potatoes, significantly (P < 0.001) increasing the mean wet weight of shoots and roots in in vitro bacterization studies. Barnyard grass was a consistently poor source of such isolates. Species-abundance measures of root zone bacterial biodiversity were not found, in this instance, to be a particularly good predictor of the presence or absence of PGP rhizobacteria. We consider that the study of complementary crops and soil-conditioning treatments should not preclude the examination of weed species as possible beneficials, as alterations in rhizobacterial biodiversity and functional versatility can influence the numbers and types of PGP bacterial strains, and consequently may serve to improve soil quality. PMID:11766050

Sturz, A V; Matheson, B G; Arsenault, W; Kimpinski, J; Christie, B R

2001-11-01

186

Prevalence of Extended-Spectrum Beta-Lactamases in Enterobacteriaceae, Pseudomonas and Stenotrophomonas as Determined by the VITEK 2 and E Test Systems in a Kuwait Teaching Hospital  

Microsoft Academic Search

Objective: To determine the prevalence of extended-spectrum ?-lactamase (ESBL)-producing members of the Enterobacteriaceae using VITEK 2 and E test systems. Materials and Methods: A total of 3,592 consecutive gram-negative isolates (single isolate per patient) of the family of Enterobacteriaceae and Pseudomonas adjudged to be clinically relevant to the patients infection were studied for ESBL production over a period of 1

Wafaa Jamal; V. O. Rotimi; Fatima Khodakhast; Rolla Saleem; Aleyamma Pazhoor; Ghyada Al Hashim

2005-01-01

187

Molecular and Biochemical Heterogeneity of Class B Carbapenem-Hydrolyzing ?-Lactamases in Chryseobacterium meningosepticum  

PubMed Central

Although the carbapenem-hydrolyzing ?-lactamase (CH?L) BlaB-1 is known to be in Chryseobacterium meningosepticum NCTC 10585, a second CH?L gene, blaGOB-1, was cloned from another C. meningosepticum clinical isolate (PINT). The G+C content of blaGOB-1 (36%) indicated the likely chromosomal origin of this gene. Its expression in Escherichia coli DH10B yields a mature CH?L with a pI of 8.7 and a relative molecular mass of 28.2 kDa. In E. coli, GOB-1 conferred resistance to narrow-spectrum cephalosporins and reduced susceptibility to ureidopenicillins, broad-spectrum cephalosporins, and carbapenems. GOB-1 had a broad-spectrum hydrolysis profile including penicillins and cephalosporins (but not aztreonam). The catalytic efficiency for meropenem was higher than for imipenem. GOB-1 had low amino acid identity with the class B CH?Ls, sharing 18% with the closest, L-1 from Stenotrophomonas maltophilia, and only 11% with BlaB-1. Most of the conserved amino acids that may be involved in the active site of CH?Ls (His-101, Asp-103, His-162, and His-225) were identified in GOB-1. Sequence heterogeneity was found for GOB-1-like and BlaB-1-like ?-lactamases, having 90 to 100% and 86 to 100% amino acid identity, respectively, among 10 unrelated C. meningosepticum isolates. Each isolate had a GOB-1-like and a BlaB-1-like gene. The same combination of GOB-1-like and BlaB-1-like ?-lactamases was not found in two different isolates. C. meningosepticum is a bacterial species with two types of unrelated chromosome-borne class B CH?Ls that can be expressed in E. coli and, thus, may represent a clinical threat if spread in gram-negative aerobes. PMID:10858348

Bellais, Samuel; Aubert, Daniel; Naas, Thierry; Nordmann, Patrice

2000-01-01

188

Biosynthesis and structural characterization of silver nanoparticles from bacterial isolates  

SciTech Connect

Graphical abstract: In this study five bacterial isolates belong to different genera were found to be able to biosynthesize silver nanoparticles. Biosynthesis and spectral characterization are reported here. Highlights: {yields} About 300 bacterial isolates were screened for their ability to produce nanosilvers {yields} Five of them were potential candidates for synthesis of silver nanoparticles {yields} Production of silver nanoparticles was examined using UV-Vis, XRD, SEM and EDS. {yields} The presence of nanoparticles with all five bacterial isolates was confirmed. -- Abstract: This study aimed to develop a green process for biosynthesis of silver nanomaterials by some Egyptian bacterial isolates. This target was achieved by screening an in-house culture collection consists of 300 bacterial isolates for silver nanoparticle formation. Through screening process, it was observed that strains belonging to Escherichia coli (S30, S78), Bacillus megaterium (S52), Acinetobacter sp. (S7) and Stenotrophomonas maltophilia (S54) were potential candidates for synthesis of silver nanoparticles. The extracellular production of silver nanoparticles by positive isolates was investigated by UV-Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results demonstrated that UV-visible spectrum of the aqueous medium containing silver ion showed a peak at 420 nm corresponding to the plasmon absorbance of silver nanoparticles. Scanning electron microscopy micrograph showed formation of silver nanoparticles in the range of 15-50 nm. XRD-spectrum of the silver nanoparticles exhibited 2{theta} values corresponding to the silver nanocrystal that produce in hexagonal and cubic crystal configurations with different plane of orientation. In addition, the signals of the silver atoms were observed by EDS-spectrum analysis that confirms the presence of silver nanoparticles (AgNPs) in all positive bacterial isolates.

Zaki, Sahar, E-mail: saharzaki@yahoo.com [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt)] [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt); El Kady, M.F. [Fabrication Technology Department, Advanced Technology and New Materials Research Institute (ATNMRI), Mubarak City for Scientific Research and Technology Applications, Alexandria (Egypt)] [Fabrication Technology Department, Advanced Technology and New Materials Research Institute (ATNMRI), Mubarak City for Scientific Research and Technology Applications, Alexandria (Egypt); Abd-El-Haleem, Desouky [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt)] [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt)

2011-10-15

189

Microbe associated molecular patterns from rhizosphere bacteria trigger germination and Papaver somniferum metabolism under greenhouse conditions.  

PubMed

Ten PGPR from different backgrounds were assayed on Papaver somniferum var. Madrigal to evaluate their potential as biotic elicitors to increase alkaloid content under the rationale that some microbe associated molecular patterns (MAMPs) are able to trigger plant metabolism. First, the 10 strains and their culture media at two different concentrations were tested for their ability to trigger seed germination. Then, the best three strains were tested for their ability to increase seedling growth and alkaloid levels under greenhouse conditions. Only three strains and their culture media enhanced germination. Then, germination enhancing capacity of these best three strains, N5.18 Stenotrophomonas maltophilia, Aur9 Chryseobacterium balustinum and N21.4 Pseudomonas fluorescens was evaluated in soil. Finally, the three strains were applied on seedlings at two time points, by soil drench or by foliar spray. Photosynthesis was measured, plant height was recorded, capsules were weighted and alkaloids analyzed by HPLC. Only N5.18 delivered by foliar spray significantly increased plant height coupled to an increase in total alkaloids and a significant increase in opium poppy straw dry weight; these increases were supported by a better photosynthetic efficiency. The relative contents of morphine, thebaine, codeine and oripavine were affected by this treatment causing a significant increase in morphine coupled to a decrease in thebaine, demonstrating the effectivity of MAMPs from N5.18 in this plant species. Considering the increase in capsule biomass and alkaloids together with the acceleration of germination, strain N5.18 appears as a good candidate to elicit plant metabolism and consequently, to increase productivity of Papaver somniferum. PMID:24296249

Bonilla, A; Sarria, A L F; Algar, E; Muoz Ledesma, F J; Ramos Solano, B; Fernandes, J B; Gutierrez Maero, F J

2014-01-01

190

Effects of Agaricus lilaceps fairy rings on soil aggregation and microbial community structure in relation to growth stimulation of western wheatgrass (Pascopyrum smithii) in Eastern Montana rangeland.  

PubMed

Stimulation of plant productivity caused by Agaricus fairy rings has been reported, but little is known about the effects of these fungi on soil aggregation and the microbial community structure, particularly the communities that can bind soil particles. We studied three concentric zones of Agaricus lilaceps fairy rings in Eastern Montana that stimulate western wheatgrass (Pascopyrum smithii): outside the ring (OUT), inside the ring (IN), and stimulated zone adjacent to the fungal fruiting bodies (SZ) to determine (1) soil aggregate proportion and stability, (2) the microbial community composition and the N-acetyl-?-D-glucosaminidase activity associated with bulk soil at 0-15 cm depth, (3) the predominant culturable bacterial communities that can bind to soil adhering to wheatgrass roots, and (4) the stimulation of wheatgrass production. In bulk soil, macroaggregates (4.75-2.00 and 2.00-0.25 mm) and aggregate stability increased in SZ compared to IN and OUT. The high ratio of fungal to bacteria (fatty acid methyl ester) and N-acetyl-?-D-glucosaminidase activity in SZ compared to IN and OUT suggest high fungal biomass. A soil sedimentation assay performed on the predominant isolates from root-adhering soil indicated more soil-binding bacteria in SZ than IN and OUT; Pseudomonas fluorescens and Stenotrophomonas maltophilia isolates predominated in SZ, whereas Bacillus spp. isolates predominated in IN and OUT. This study suggests that growth stimulation of wheatgrass in A. lilaceps fairy rings may be attributed to the activity of the fungus by enhancing soil aggregation of bulk soil at 0-15 cm depth and influencing the amount and functionality of specific predominant microbial communities in the wheatgrass root-adhering soil. PMID:23455430

Caesar-Tonthat, The Can; Espeland, Erin; Caesar, Anthony J; Sainju, Upendra M; Lartey, Robert T; Gaskin, John F

2013-07-01

191

Granulation, control of bacterial contamination, and enhanced lipid accumulation by driving nutrient starvation in coupled wastewater treatment and Chlorella regularis cultivation.  

PubMed

Bacterial contamination and biomass harvesting are still challenges associated with coupling of microalgae and wastewater treatment technology. This study investigated aggregation, bacterial growth, lipid production, and pollutant removal during bacteria contaminated Chlorella regularis cultivation under nutrient starvation stress, by supposing the C/N/P ratios of the medium to 14/1.4/1 (MB?.?) and 44/1.4/1 (MB?.?), respectively. Granules of 500-650 ?m were formed in the bacteria contaminated inoculum; however, purified C. regularis were generally suspended freely in the medium, indicating that bacterial presence was a prerequisite for granulation. Extracellular polymeric substance (EPS) analysis showed that polysaccharides were dominant in granules, while protein mainly distributed in the outer layer. Denaturing gradient gel electrophoresis (DGGE) results revealed Sphingobacteriales bacterium and Sphingobacterium sp. are vital organisms involved in the flocculation of microalgae, and nitrifiers (Stenotrophomonas maltophilia) could co-exist in the granular. Both EPS and DGGE results further supported that bacteria played key roles in granulation. C. regularis was always dominant and determined the total biomass concentration during co-cultivation, but bacterial growth was limited owing to nutrient deficiency. Starvation strategy also contributed to enhancement of lipid accumulation, as lipid content in MB?.? with a greater C/N/P led to the greatest increase in the starvation period, and the maximum lipid productivity reached 0.057 g/(Lday). Chemical oxygen demand and nitrogen removal in MB?.? reached 92 and 96%, respectively, after 3 days of cultivation. Thus, cultivation of microalgae in high C/N/P wastewater enabled simultaneous realization of biomass granulation, bacterial overgrowth limitation, enhanced lipid accumulation, and wastewater purification. PMID:25520170

Zhou, Dandan; Li, Yunbao; Yang, Yang; Wang, Yao; Zhang, Chaofan; Wang, Di

2015-02-01

192

Evaluation of humoral immune response to nosocomial pathogen and functional status in elderly patients with sepsis.  

PubMed

The clinical significance of humoral immune response to nosocomial pathogens and functional status in elderly patients with sepsis is not clear. We evaluated the humoral immune to nosocomial pathogens and the effect of functional dependencies on clinical outcomes among elderly patients with sepsis. This study prospectively enrolled patients aged ?65 years with sepsis from September 2011 to May 2012 at a 2000-bed university hospital. The data including CD4 and CD8 T-cell count, functional status by measuring basic activities of daily living (ADL) and instrumental activities of daily living (IADL) were collected for all patients. In addition, the collected blood samples were analyzed for serum antibody levels against nosocomial pathogens using an ELISA. During the study period, 72 patients (38 males) treated with sepsis were enrolled. The all-cause in-hospital mortality rate was 16.7% (12/72). The mean CD4/CD8 T-cell ratio was significantly lower in nonsurvivors than in survivors (1.08 0.72 vs. 1.93 1.42, P=0.003). Serum antibody titers to Acinetobacter baumannii, Klebsiella pneumonia, Stenotrophomonas maltophilia, and Enterococcus faecalis were statistically higher in nonsurvivors than in survivors. On multivariate analysis, the IADL score was independently predictive of mortality in elderly patients with sepsis (odds ratio 1.410, 95% confidence interval 1.007-1.975, P=0.046). These results suggest that IADL scores could be used as predictors to identify elderly patients with a poor prognosis of nosocomial infections. PMID:23998496

Jeong, Su Jin; Yoon, Sang Sun; Han, Sang Hoon; Yong, Dong Eun; Kim, Chang Oh; Kim, June Myung

2014-01-01

193

Anti-cancer, immunoregulatory, and antimicrobial activities of the frog skin host-defense peptides pseudhymenochirin-1Pb and pseudhymenochirin-2Pa.  

PubMed

Pseudhymenochirin-1Pb (Ps-1Pb) and pseudhymenochirin-2Pa (Ps-2Pa) are host-defense peptides, first isolated from skin secretions of the frog Pseudhymenochirus merlini (Pipidae). Ps-1Pb and Ps-2Pa are highly cytotoxic (LC50<12 ?M) against non-small cell lung adenocarcinoma A549 cells, breast adenocarcinoma MDA-MB-231 cells, and colorectal adenocarcinoma HT-29 cells but are also hemolytic against human erythrocytes (LC50=282 ?M for Ps-1Pb and LC50=61 ?M for Ps-2Pa). Ps-2Pa shows selective cytotoxicity for tumor cells (LC50 against non-neoplastic human umbilical vein (HUVEC) cells=682 ?M). Ps-1Pb and Ps-2Pa (5 ?g/mL) significantly inhibit production of the anti-inflammatory cytokine IL-10 and the multifunctional cytokine IL-6 from lipopolysaccharide (LPS)-stimulated peritoneal macrophages from C57BL/6 mice and enhance the production of the pro-inflammatory cytokine IL-23 from both unstimulated and LPS-stimulated macrophages. Ps-1Pb potently (MIC?10 ?M) inhibits growth of multidrug-resistant clinical isolates of the Gram-positive bacteria methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis, and the Gram-negative bacteria Acinetobacter baumannii and Stenotrophomonas maltophilia. Ps-2Pa shows the same high potency (MIC?10 ?M) against the Gram-positive bacteria but is 2-4 fold less potent against the Gram-negative isolates. Ps-1Pb at 4MIC kills 99.9% of Escherichia coli within 30 min and 99.9% of S. aureus within 180 min. In conclusion, cytotoxicity against tumor cells, cytokine-mediated immunomodulatory properties, and broad-spectrum antimicrobial activity suggest that the Ps-1Pb and Ps-2Pa represent templates for design of non-hemolytic analogs for tumor therapy and for treatment of infections in cancer patients produced by multidrug-resistant pathogens. PMID:25447194

Mechkarska, Milena; Attoub, Samir; Sulaiman, Shahrazad; Pantic, Jelena; Lukic, Miodrag L; Conlon, J Michael

2014-11-01

194

Exploring nicotinamide cofactor promiscuity in NAD(P)H-dependent flavin containing monooxygenases (FMOs) using natural variation within the phosphate binding loop. Structure and activity of FMOs from Cellvibrio sp. BR and Pseudomonas stutzeri NF13.  

PubMed

Flavin-containing monooxygenases (FMOs) catalyse asymmetric oxidation reactions that have potential for preparative organic synthesis, but most use the more expensive, phosphorylated nicotinamide cofactor NADPH to reduce FAD to FADH2 prior to formation of the (hydro)peroxy intermediate required for substrate oxygenation. A comparison of the structures of NADPH-dependent FMO from Methylophaga aminisulfidivorans (mFMO) and SMFMO from Stenotrophomonas maltophilia, which is able to use both NADPH and NADH, suggested that the promiscuity of the latter enzyme may be due in part to the substitution of an Arg-Thr couple in the NADPH phosphate recognition site in mFMO, for a Gln-His couple in SMFMO (Jensen et al., 2012, Chembiochem, 13, 872-878). Natural variation within the phosphate binding region, and its influence on nicotinamide cofactor promiscuity, was explored through the cloning, expression, characterisation and structural studies of FMOs from Cellvibrio sp. BR (CFMO) and Pseudomonas stutzeri NF13 (PSFMO), which possess Thr-Ser and Gln-Glu in the putative phosphate recognition positions, respectively. CFMO and PSFMO displayed 5- and 1.5-fold greater activity, respectively, than SMFMO for the reduction of FAD with NADH, and were also cofactor promiscuous, displaying a ratio of activity with NADH:NADPH of 1.7:1 and 1:1.3, respectively. The structures of CFMO and PSFMO revealed the context of the phosphate binding loop in each case, and also clarified the structure of the mobile helix-loop-helix motif that appears to shield the FAD-binding pocket from bulk solvent in this class of FMOs, a feature that was absent from the structure of SMFMO. PMID:25383040

Jensen, Chantel N; Ali, Sohail T; Allen, Michael J; Grogan, Gideon

2014-11-01

195

[Utility of prolonged incubation and terminal subcultures of blood cultures from immunocompromised patients].  

PubMed

The value of blind terminal subcultures (7 and 30 days) and prolonged incubation (30 days) of blood cultures from immunosuppressed patients was analyzed in the Fundacin Favaloro, the Fundacin para la Lucha contra las Enfermedades Neurolgicas de la Infancia and the Hospital de Nios Ricardo Gutirrez. A total of 2707 blood cultures and 369 patients were included (transplantation of solid organs 154, oncohematologic disorders 106 and solid tumors 109). Bact-Alert bottles were incubated at 35 degrees C for 30 days in the Bact-Alert System. Bottles with positive signals were routinely removed, and aliquots of the broth were Gram stained and subcultured aerobically in chocolate agar and Sabouraud agar. A total of 136 bacteremic episodes were obtained. The positivization time of blood cultures was 81.6% at 24 h, 93.3% at 48 h, 94.5% at 72 h and 97.7% within 7 days. Only 3 (2.2%) episodes were positive by blind terminal subcultures and 1 (0.75%) by prolonged incubation (14 days). The median time and range of positivization in hours were 13.8 and 2.2-168, respectively. The microorganisms isolated were coagulase negative staphylococci (n = 24), Klebsiella pneumoniae (n = 22), Staphylococcus aureus (n = 21), Escherichia coli (n = 18), Acinetobacter spp (n = 9), Candida spp (n = 8), Pseudomonas aeruginosa (n = 6), Enterobacter cloacae (n = 5), Stenotrophomonas maltophilia (n = 5), Enterococcus faecalis, Salmonella spp and Capnocytophaga sputigena (n = 2), Enterobacter aerogenes, Enterococcus faecium, Citrobacter diversus, Candida albicans, Klebsiella oxytoca, Chryseomonas luteola, Serratia marcescens, Abiotrophia spp, Campylobacter jejuni, Moraxella catarrhalis, Moraxella urethralis, Neisseria sicca, beta hemolytic group G streptococci, Rhodococcus equi, Micrococcus spp, Cryptococcus neoformans and Streptococcus mitis (n = 1). In our experience, blind terminal subcultures and prolonged incubation of blood cultures from immunosuppressed patients are unnecessary and cost expensive. PMID:11594009

Soloaga, R; Procopio, A; Manganello, S; Ivanovic, V; Romay, N; Pirosanto, Y; Fernndez, A; Zudiker, R; Echeverra, A; Nagel, C; del Castillo, M; Lpez, E; Gutfraind, Z; Tokumoto, M; Guelfand, L

2001-01-01

196

Diversity of bacteria nesting the plant cover of north Sinai deserts, Egypt  

PubMed Central

North Sinai deserts were surveyed for the predominant plant cover and for the culturable bacteria nesting their roots and shoots. Among 43 plant species reported, 13 are perennial (e.g. Fagonia spp., Pancratium spp.) and 30 annuals (e.g. Bromus spp., Erodium spp.). Eleven species possessed rhizo-sheath, e.g. Cyperus capitatus, Panicum turgidum and Trisetaria koelerioides. Microbiological analyses demonstrated: the great diversity and richness of associated culturable bacteria, in particular nitrogen-fixing bacteria (diazotrophs); the majority of bacterial residents were of true and/or putative diazotrophic nature; the bacterial populations followed an increasing density gradient towards the root surfaces; sizeable populations were able to reside inside the root (endorhizosphere) and shoot (endophyllosphere) tissues. Three hundred bacterial isolates were secured from studied spheres. The majority of nitrogen-fixing bacilli isolates belonged to Bacillus megaterium,Bacillus pumilus, Bacillus polymexa,Bacillus macerans,Bacillus circulans and Bacillus licheniformis. The family Enterobacteriaceae represented by Enterobacter agglomerans,Enterobacter sackazakii, Enterobacter cloacae, Serratia adorifera,Serratia liquefaciens and Klebsiella oxytoca. The non-Enterobacteriaceae population was rich in Pantoae spp., Agrobacterium rdiobacter, Pseudomonas vesicularis, Pseudomonas putida, Stenotrophomonas maltophilia, Ochrobactrum anthropi, Sphingomonas paucimobilis and Chrysemonas luteola.Gluconacetobacter diazotrophicus were reported inside root and shoot tissues of a number of tested plants. The dense bacterial populations reported speak well to the very possible significant role played by the endophytic bacterial populations in the survival, in respect of nutrition and health, of existing plants. Such groups of diazotrophs are good candidates, as bio-preparates, to support the growth of future field crops grown in deserts of north Sinai and irrigated by the water of El-Salam canal. PMID:25685397

Hanna, Amira L.; Youssef, Hanan H.; Amer, Wafaa M.; Monib, Mohammed; Fayez, Mohammed; Hegazi, Nabil A.

2012-01-01

197

Evaluation of Microorganisms Cultured from Injured and Repressed Tissue Regeneration Sites in Endangered Giant Aquatic Ozark Hellbender Salamanders  

PubMed Central

Investigation into the causes underlying the rapid, global amphibian decline provides critical insight into the effects of changing ecosystems. Hypothesized and confirmed links between amphibian declines, disease, and environmental changes are increasingly represented in published literature. However, there are few long-term amphibian studies that include data on population size, abnormality/injury rates, disease, and habitat variables to adequately assess changes through time. We cultured and identified microorganisms isolated from abnormal/injured and repressed tissue regeneration sites of the endangered Ozark Hellbender, Cryptobranchus alleganiensis bishopi, to discover potential causative agents responsible for their significant decline in health and population. This organism and our study site were chosen because the population and habitat of C. a. bishopi have been intensively studied from 19692009, and the abnormality/injury rate and apparent lack of regeneration were established. Although many bacterial and fungal isolates recovered were common environmental organisms, several opportunistic pathogens were identified in association with only the injured tissues of C.a. bishopi. Bacterial isolates included Aeromonas hydrophila, a known amphibian pathogen, Granulicetella adiacens, Gordonai terrae, Stenotrophomonas maltophilia, Aerococcus viridans, Streptococcus pneumoniae and a variety of Pseudomonads, including Pseudomonas aeruginosa, P. stutzeri, and P. alcaligenes. Fungal isolates included species in the genera Penicillium, Acremonium, Cladosporium, Curvularia, Fusarium, Streptomycetes, and the Class Hyphomycetes. Many of the opportunistic pathogens identified are known to form biofilms. Lack of isolation of the same organism from all wounds suggests that the etiological agent responsible for the damage to C. a. bishopi may not be a single organism. To our knowledge, this is the first study to profile the external microbial consortia cultured from a Cryptobranchid salamander. The incidence of abnormalities/injury and retarded regeneration in C. a. bishopi may have many contributing factors including disease and habitat degradation. Results from this study may provide insight into other amphibian population declines. PMID:22205979

Nickerson, Cheryl A.; Ott, C. Mark; Castro, Sarah L.; Garcia, Veronica M.; Molina, Thomas C.; Briggler, Jeffrey T.; Pitt, Amber L.; Tavano, Joseph J.; Byram, J. Kelly; Barrila, Jennifer; Nickerson, Max A.

2011-01-01

198

Antibacterial agents and heavy metal resistance in Gram-negative bacteria isolated from seawater, shrimp and sediment in Iskenderun Bay, Turkey.  

PubMed

The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from seawater, sediment and shrimps, and to determine if there is a relationship between antibiotic and heavy metal resistance. We undertook studies in 2007 in the industrially polluted Iskenderun Bay, on the south coast of Turkey. The resistance of 236 Gram-negative bacterial isolates (49 from seawater, 90 from sediment and 97 from shrimp) to 16 different antibiotics, and to 5 heavy metals, was investigated by agar diffusion and agar dilution methods, respectively. A total of 31 species of bacteria were isolated: the most common strains isolated from all samples were Escherichia coli (11.4%), Aeromonas hydrophila (9.7%) and Stenotrophomonas maltophilia (9.3%). There was a high incidence of resistance to ampicillin (93.2%), streptomycin (90.2%) and cefazolin (81.3%), and a low incidence of resistance to imipenem (16.5%), meropenem (13.9%) and cefepime (8.0%). Some 56.8% of all bacteria isolated from seawater, sediment and shrimp were resistant to 7 or more antibiotics. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from 12.5 microg/ml to > 3200 microg/ml. The bacteria from seawater, sediment and shrimp showed high resistance to cadmium of 69.4%, 88.9%, and 81.1% respectively, and low resistance to manganese of 2%, 6.7% and 11.3% respectively. The seawater and sediment isolates which were metal resistant also showed a high resistance to three antibiotics: streptomycin, ampicillin and trimethoprim-sulphamethoxazole. In contrast, the shrimp isolates which were metal resistant were resistant to four antibiotics: cefazolin, nitrofurantoin, cefuroxime and ampicillin. Our results show that Iskenderun Bay has a significant proportion of antibiotic and heavy metal resistant Gram-negative bacteria, and these bacteria constitute a potential risk for public health. PMID:18804847

Matyar, Fatih; Kaya, Aysenur; Diner, Sadik

2008-12-15

199

Bacterial reduction of selenium in coal mine tailings pond sediment  

SciTech Connect

Sediment from a storage facility for coal tailings solids was assessed for its capacity to reduce selenium (Se) by native bacterial community. One Se{sup 6+}-reducing bacterium Enterobacter hormaechei (Tar11) and four Se{sup 4+}-reducing bacteria, Klebsiella pneumoniae (Tar1), Pseudomonasfluorescens (Tar3), Stenotrophomonas maltophilia (Tar6), and Enterobacter amnigenus (Tar8) were isolated from the sediment. Enterobacter horinaechei removed 96% of the added Se{sup 6+} (0.92 mg L{sup -1} from the effluents when Se6+ was determined after 5 d of incubation. Analysis of the red precipitates showed that Se{sup 6+} reduction resulted in the formation of spherical particles ({lt}1.0 {mu} m) of Se 0 as observed under scanning electron microscope (SEM) and confirmed by EDAX. Selenium speciation was performed to examine the fate of the added Se{sup 6+} in the sediment with or without addition of Enterobacter hormaechei cells. More than 99% of the added Se{sup 6+} (about 2.5 mg L{sup -1}) was transformed in the nonsterilized sediment (without Enterobacter hormaechei cells) as well as in the sterilized (heat-killed) sediment (with Enterobacter hormaechei cells). The results of this study suggest that the lagoon sediments at the mine site harbor Se{sup 6+}- and Se{sup 4+} -reducing bacteria and may be important sinks for soluble Se (Se{sup 6+} and Se{sup 4+}). Enterobacter hormaechei isolated from metal-contaminated sediment may have potential application in removing Se from industrial effluents.

Siddique, T.; Arocena, J.M.; Thring, R.W.; Zhang, Y.Q. [University of North British Columbia, Prince George, BC (Canada)

2007-05-15

200

Persistence of Nosocomial Pathogens on Various Fabrics  

PubMed Central

Objective: Fabrics can become contaminated with high numbers of microorganisms that may be pathogenic to patients in a hospital setting and can play an important role in the chain of infection. The aim of this study was to investigate the survival of several clinical bacterial and fungal isolates on several fabrics commonly used in hospitals. Materials and Methods: Bacterial and fungal survival was tested on the following materials, each of which are commonly used in our hospital: 100% smooth cotton, 60% cotton-40% polyester, 100% wool and 100% silk. One isolate each of Candida albicans, Candida tropicalis, Candida krusei, Candida glabrata, Candida parapsilosis, Geotrichum candidum, Aspergillus fumigatus, Cryptococcus neoformans, vancomycin resistant Enterococcus faecium (VRE, methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum beta-lactamase (ESBL) positive Escherichia coli, inducible beta-lactamase (IBL) positive Pseudomonas aeruginosa, IBL-positive Acinetobacter baumannii and Stenotrophomonas maltophilia were used to contaminate fabrics. The survival of these microorganisms was studied by testing the fabric swatches for microbial growth. Results: The median survival times for all the tested bacteria and fungi were as follows: 26 days on cotton, 26.5 days on cotton-polyester, 28 days on silk, and 30 days on wool. Among the bacterial species tested, E. faecium had the longest survival time on cotton-polyester fabrics. For the fungal isolates, it was observed that C. tropicalis and C. krusei survived for the shortest amount of time on cotton fabrics in the present study. Conclusion: This survival data indicate that pathogenic microorganisms can survive from days to months on commonly used hospital fabrics. These findings indicate that current recommendations for the proper disinfection or sterilization of fabrics used in hospitals should be followed to minimize cross-contamination and prevent nosocomial infections. PMID:25610201

Koca, Ozlem; Altoparlak, Ulku; Ayyildiz, Ahmet; Kaynar, Hasan

2012-01-01

201

Diversity of bacteria nesting the plant cover of north Sinai deserts, Egypt.  

PubMed

North Sinai deserts were surveyed for the predominant plant cover and for the culturable bacteria nesting their roots and shoots. Among 43 plant species reported, 13 are perennial (e.g. Fagonia spp., Pancratium spp.) and 30 annuals (e.g. Bromus spp., Erodium spp.). Eleven species possessed rhizo-sheath, e.g. Cyperus capitatus, Panicum turgidum and Trisetaria koelerioides. Microbiological analyses demonstrated: the great diversity and richness of associated culturable bacteria, in particular nitrogen-fixing bacteria (diazotrophs); the majority of bacterial residents were of true and/or putative diazotrophic nature; the bacterial populations followed an increasing density gradient towards the root surfaces; sizeable populations were able to reside inside the root (endorhizosphere) and shoot (endophyllosphere) tissues. Three hundred bacterial isolates were secured from studied spheres. The majority of nitrogen-fixing bacilli isolates belonged to Bacillus megaterium, Bacillus pumilus, Bacillus polymexa, Bacillus macerans, Bacillus circulans and Bacillus licheniformis. The family Enterobacteriaceae represented by Enterobacter agglomerans, Enterobacter sackazakii, Enterobacter cloacae, Serratia adorifera, Serratia liquefaciens and Klebsiella oxytoca. The non-Enterobacteriaceae population was rich in Pantoae spp., Agrobacterium rdiobacter, Pseudomonas vesicularis, Pseudomonas putida, Stenotrophomonas maltophilia, Ochrobactrum anthropi, Sphingomonas paucimobilis and Chrysemonas luteola. Gluconacetobacter diazotrophicus were reported inside root and shoot tissues of a number of tested plants. The dense bacterial populations reported speak well to the very possible significant role played by the endophytic bacterial populations in the survival, in respect of nutrition and health, of existing plants. Such groups of diazotrophs are good candidates, as bio-preparates, to support the growth of future field crops grown in deserts of north Sinai and irrigated by the water of El-Salam canal. PMID:25685397

Hanna, Amira L; Youssef, Hanan H; Amer, Wafaa M; Monib, Mohammed; Fayez, Mohammed; Hegazi, Nabil A

2013-01-01

202

Bacterial resistance control on mineral surfaces of hydroxyapatite and human teeth via surface charge-driven antifouling coatings.  

PubMed

This works reports a set of new functionalized polyethyleneimine (PEI) polymers, including a neutral PEGylated polymer PEI-g-PEGMA, a negatively charged polymer PEI-g-SA, and a zwitterionic polymer PEI-g-SBMA, and their use as antibiofouling coating agent for human teeth protection. Polymers were synthesized by Michael addition, XPS analysis revealed that each polymer could be efficiently coated onto hydroxyapatite, ceramic material used as a model tooth. Polymers carrying a negative net charge were more efficiently adsorbed, because of the establishment of electrostatic interactions with calcium ions. Protein adsorption tests revealed that two factors were important in the reduction of protein adsorption. Both the surface charge and the surface ability to bind and entrap water molecules had to be considered. PEI-g-SBMA, which zeta potential in PBS solution was negative, was efficient to inhibit the adsorption of BSA, a negative protein. On the other hand, it also resisted the adsorption of lysozyme, a positive protein, because zwitterionic molecules can easily entrap water and provide a very hydrophilic environment. Streptococcus mutans attachment tests performed unveiled that all modified polymers were efficient to resist this type of bacteria responsible for dental carries. Best results were also obtained with PEI-g-SBMA coating. This polymer was also shown to efficiently resist the adsorption of positively charged bacteria (Stenotrophomonas maltophilia). Tests performed on real human tooth showed that PEI-g-SBMA could inhibit up to 70% of bacteria adhesion, which constitutes a major result considering that surface of teeth is very rough, therefore physically promoting the attachment of proteins and bacteria. PMID:24513459

Venault, Antoine; Yang, Hui-Shan; Chiang, Yen-Che; Lee, Bor-Shuinn; Ruaan, Ruoh-Chyu; Chang, Yung

2014-03-12

203

Conformational analysis and cytotoxic activities of the frog skin host-defense peptide, hymenochirin-1Pa.  

PubMed

Hymenochirin-1Pa (LKLSPKTKDTLKKVLKGAIKGAIAIASMA-NH2) is a host-defense peptide first isolated from skin secretions of the frog Pseudhymenochirus merlini (Pipidae). A nuclear magnetic resonance structural investigation demonstrates that the peptide has a random coil conformation in water but, in the membrane-mimetic solvent 50% (v/v) trifluoroethanol-water adopts a well-defined conformation characterized by two ?-helical domains from residues K6 to G17 and from G21 to M28, with the N-terminal region unfolded. The presence of a GXXXG domain, the most common structural motif found at the interface between interacting trans-membrane helices, between residues 17 and 21, introduces a kink corresponding to a deviation from linearity of 93 31. Hymenochirin-1Pa shows broad spectrum anti-bacterial activity, including high potency against multidrug-resistant clinical isolates of Staphylococcus aureus, Acinetobacter baumannii, and Stenotrophomonas maltophilia. The peptide also shows high cytotoxic potency against human non-small lung adenocarcinoma A549 cells, breast adenocarcinoma MDA-MB-231 cells, and colorectal adenocarcinoma HT-29 cells but its therapeutic potential as an anti-cancer agent is limited by moderate hemolytic activity against human erythrocytes and lack of selectivity for tumor cells. Increasing cationicity of the peptide by substituting the Asp(9) residue by either L-Lys (K) or D-Lys (k) has relatively minor effects on antimicrobial and anti-tumor potencies but the [D9k] analog is non-hemolytic LC50 > 400 ?M. Thus, [D9k]hymenochirin-1Pa may serve as a template for the design of non-toxic antimicrobial agents for use against multidrug-resistant pathogenic bacteria. PMID:25241629

Serra, Ilaria; Scorciapino, Mariano A; Manzo, Giorgia; Casu, Mariano; Rinaldi, Andrea C; Attoub, Samir; Mechkarska, Milena; Conlon, J Michael

2014-11-01

204

[Diagnostic and therapeutic management of Gram-negative infections].  

PubMed

Among Gram negative bacteria, Pseudomonas aeruginosa, the extended spectrum beta-lactamases (ESBL)-producing strains, Acinetobacter spp, in particular the multiresistant Acinetobacter baumannii, and Stenotrophomonas maltophilia are the most implicated micrororganisms in the ever more increasing problem of bacterial resistance. Possible solutions have to be searched, on one hand, in the use of new drugs but, on the other hand, in the re-evaluation of those already available drugs, possibly considering a new role for old drugs such as colistine and fosfomycin. Concerning ESBL-producing strains, the most recent data provided by EARSS report, in Italy, an incidence rate of 10-25 percent. The insurgence of an infection sustained by an ESBL+ve strain is strictly related to some well known risk factors, like the hospital stay itself, the disease severity, the length of stay in ICU, intubation and mechanical ventilation, catheterization, urinary or artery, and the past exposure to antibiotics. The raise in ESBL producing strains is closely related to the increasing use of cephalosporins. In the setting of a Gram negative infection, the combination therapy guarantees a higher coverage by reducing insurgence of possible resistance mechanisms, possibly resulting synergistic, and allowing a de-escalation therapy, although to this latter other problems, such as tolerability, costs and compliance, can be related. Another basic aspect to take into account of, in order to achieve the maximal efficacy of the antibiotic treatment, is the right dosage. In the idea to look for the best approach for the antibiotic treatment of a severe infection in a hospital setting, when a Gram negative aetiology is implicated, it can be possibly presumed that the right way consists in avoiding inappropriate antibiotic therapies, making therapeutic choices based on guidelines resulted from local epidemiological data, initiating the therapy promptly, avoiding excessive use of antibiotics, possibly modifying therapy at the light of clinical data and microbiological results (de-escalation). PMID:18843221

Bassetti, Matteo; Repetto, Ernestina

2008-04-01

205

Chlor-alkali plant contamination of Aussa River sediments induced a large Hg-resistant bacterial community  

NASA Astrophysics Data System (ADS)

A closed chlor-alkali plant (CAP) discharged Hg for decades into the Aussa River, which flows into Marano Lagoon, resulting in the large-scale pollution of the lagoon. In order to get information on the role of bacteria as mercury detoxifying agents, analyses of anions in the superficial part (0-1 cm) of sediments were conducted at four stations in the Aussa River. In addition, measurements of biopolymeric carbon (BPC) as a sum of the carbon equivalent of proteins (PRT), lipids (LIP), and carbohydrates (CHO) were performed to correlate with bacterial biomass such as the number of aerobic heterotrophic cultivable bacteria and their percentage of Hg-resistant bacteria. All these parameters were used to assess the bioavailable Hg fraction in sediments and the potential detoxification activity of bacteria. In addition, fifteen isolates were characterized by a combination of molecular techniques, which permitted their assignment into six different genera. Four out of fifteen were Gram negative with two strains of Stenotrophomonas maltophilia, one Enterobacter sp., and one strain of Brevibacterium frigoritolerans. The remaining strains (11) were Gram positive belonging to the genera Bacillus and Staphylococcus. We found merA genes in only a few isolates. Mercury volatilization from added HgCl2 and the presence of plasmids with the merA gene were also used to confirm Hg reductase activity. We found the highest number of aerobic heterotrophic Hg-resistant bacteria (one order magnitude higher) and the highest number of Hg-resistant species (11 species out of 15) at the confluence of the River Aussa and Banduzzi's channel, which transport Hg from the CAP, suggesting that Hg is strongly detoxified [reduced to Hg(0)] at this location.

Baldi, Franco; Marchetto, Davide; Gallo, Michele; Fani, Renato; Maida, Isabel; Covelli, Stefano; Fajon, Vesna; Zizek, Suzana; Hines, Mark; Horvat, Milena

2012-11-01

206

Nosocomial and ventilator-associated pneumonia in a community hospital intensive care unit: a retrospective review and analysis  

PubMed Central

Background Nosocomial and ventilator-associated pneumonia (VAP) are causes of significant morbidity and mortality in hospitalized patients. We analyzed a) the incidence and the outcome of pneumonias caused by different pathogens in the intensive care unit (ICU) of a medium-sized twenty-four bed community hospital and b) the incidence of complications of such pneumonias requiring surgical intervention such as thoracotomy and decortication. Results We retrospectively reviewed the charts of patients diagnosed with nosocomial and ventilator-associated pneumonia in our ICU. Their bronchoalveolar lavage (BAL) and sputum cultures, antibiograms, and other clinical characteristics, including complications and need for tracheostomy, thoracotomy and decortication were studied. In a span of one year (201112), 43 patients were diagnosed with nosocomial pneumonia in our ICU. The median simplified acute physiology score (SAPS II) was 39. One or more gram negative organisms as the causative agents were present in 85% of microbiologic samples. The three most prevalent gram negatives were Stenotrophomonas maltophilia (34%), Pseudomonas aeurginosa (40%), and Acinetobacter baumannii (32%). Twenty eight percent of bronchoalveolar samples contained Staphylococcus aureus. Eight three percent of patients required mechanical ventilation postoperatively and 37% underwent tracheostony. Thirty five percent underwent thoracotomy and decortication because of further complications such as empyema and non-resolving parapneumonic effusions. A. baumannii, Klebsiella pneumonia extended spectrum beta lactam (ESBL) and P. aeurginosa had the highest prevalence of multi drug resistance (MDR). Fifteen patients required surgical intervention. Mortality from pneumonia was 37% and from surgery was 2%. Conclusion Nosocomial pneumonias, in particular the ones that were caused by gram negative drug resistant organisms and their ensuing complications which required thoracotomy and decortication, were the cause of significant morbidity in our intensive care unit. Preventative and more intensive and novel infection control interventions in reducing the incidence of nosocomial pneumonias are strongly emphasized. PMID:24725655

2014-01-01

207

Interactions in biofilms between Listeria monocytogenes and resident microorganisms from food industry premises.  

PubMed

Twenty nine bacterial strains were grown as binary culture biofilms with Listeria monocytogenes to assess their influence on the settlement of the latter on stainless steel coupons. Most of the strains had been isolated from food processing plants after cleaning and disinfection and were tentatively identified by the APILAB Plus 3.3.3 database (bioMerieux). Sixteen of them decreased L. monocytogenes biofilm colony forming units (CFU) counts. Three strains, Bacillus sp. CCL 9 an unidentified Gram-positive strain CCL 59 and Pseudomonas fluorescens E9. 1, led to a 3-log difference in CFU counts between the pure L. monocytogenes biofilms and the mixed biofilms. Eleven strains had no effect and only four, Kocuria varians CCL 73, Staphylococcus capitis CCL 54, Stenotrophomonas maltophilia CCL 47 and Comamonas testosteroni CCL 24, had a positive effect, with a 0.5- to 1.0-log increase in the L. monocytogenes biofilm CFU counts. On its own, L. monocytogenes settled as single cells, but in binary biofilms, different spatial arrangements were observed: (i) with K. varians CCL 73, K. varians CCL 56 and S. capitis CCL 54, L. monocytogenes cells gathered around the microcolonies of the partner strain; (ii) with the two Gram-negative strains, C. testosteroni CCL 24 and CCL 25, L. monocytogenes cells formed its own microcolonies. No link could be found between the exopolysaccharide production capacity of the bacterial strains in pure-culture biofilms and their effect on the L. monocytogenes population in mixed biofilms. With one strain, C. testosteroni CCL 24, adding filter-sterilized supernatant from a pure-culture biofilm to a pure culture of L. monocytogenes increased the number of L. monocytogenes cells adhering to the stainless steel coupons and forming microcolonies. This study suggests that the "house flora" can have a strong effect on the likelihood of finding L. monocytogenes on inert surfaces. PMID:15541798

Carpentier, Brigitte; Chassaing, Danielle

2004-12-15

208

Novel cyclic di-GMP effectors of the YajQ protein family control bacterial virulence.  

PubMed

Bis-(3',5') cyclic di-guanylate (cyclic di-GMP) is a key bacterial second messenger that is implicated in the regulation of many critical processes that include motility, biofilm formation and virulence. Cyclic di-GMP influences diverse functions through interaction with a range of effectors. Our knowledge of these effectors and their different regulatory actions is far from complete, however. Here we have used an affinity pull-down assay using cyclic di-GMP-coupled magnetic beads to identify cyclic di-GMP binding proteins in the plant pathogen Xanthomonas campestris pv. campestris (Xcc). This analysis identified XC_3703, a protein of the YajQ family, as a potential cyclic di-GMP receptor. Isothermal titration calorimetry showed that the purified XC_3703 protein bound cyclic di-GMP with a high affinity (K(d)?2 M). Mutation of XC_3703 led to reduced virulence of Xcc to plants and alteration in biofilm formation. Yeast two-hybrid and far-western analyses showed that XC_3703 was able to interact with XC_2801, a transcription factor of the LysR family. Mutation of XC_2801 and XC_3703 had partially overlapping effects on the transcriptome of Xcc, and both affected virulence. Electromobility shift assays showed that XC_3703 positively affected the binding of XC_2801 to the promoters of target virulence genes, an effect that was reversed by cyclic di-GMP. Genetic and functional analysis of YajQ family members from the human pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia showed that they also specifically bound cyclic di-GMP and contributed to virulence in model systems. The findings thus identify a new class of cyclic di-GMP effector that regulates bacterial virulence. PMID:25329577

An, Shi-qi; Caly, Delphine L; McCarthy, Yvonne; Murdoch, Sarah L; Ward, Joseph; Febrer, Melanie; Dow, J Maxwell; Ryan, Robert P

2014-10-01

209

Novel Cyclic di-GMP Effectors of the YajQ Protein Family Control Bacterial Virulence  

PubMed Central

Bis-(3?,5?) cyclic di-guanylate (cyclic di-GMP) is a key bacterial second messenger that is implicated in the regulation of many critical processes that include motility, biofilm formation and virulence. Cyclic di-GMP influences diverse functions through interaction with a range of effectors. Our knowledge of these effectors and their different regulatory actions is far from complete, however. Here we have used an affinity pull-down assay using cyclic di-GMP-coupled magnetic beads to identify cyclic di-GMP binding proteins in the plant pathogen Xanthomonas campestris pv. campestris (Xcc). This analysis identified XC_3703, a protein of the YajQ family, as a potential cyclic di-GMP receptor. Isothermal titration calorimetry showed that the purified XC_3703 protein bound cyclic di-GMP with a high affinity (Kd?2 M). Mutation of XC_3703 led to reduced virulence of Xcc to plants and alteration in biofilm formation. Yeast two-hybrid and far-western analyses showed that XC_3703 was able to interact with XC_2801, a transcription factor of the LysR family. Mutation of XC_2801 and XC_3703 had partially overlapping effects on the transcriptome of Xcc, and both affected virulence. Electromobility shift assays showed that XC_3703 positively affected the binding of XC_2801 to the promoters of target virulence genes, an effect that was reversed by cyclic di-GMP. Genetic and functional analysis of YajQ family members from the human pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia showed that they also specifically bound cyclic di-GMP and contributed to virulence in model systems. The findings thus identify a new class of cyclic di-GMP effector that regulates bacterial virulence. PMID:25329577

An, Shi-qi; Caly, Delphine L.; McCarthy, Yvonne; Murdoch, Sarah L.; Ward, Joseph; Febrer, Melanie; Dow, J. Maxwell; Ryan, Robert P.

2014-01-01

210

Nitrate treatment effects on bacterial community biofilm formed on carbon steel in produced water stirred tank bioreactor.  

PubMed

To better understand the impact of nitrate in Brazilian oil reservoirs under souring processes and corrosion, the goal of this study was to analyse the effect of nitrate on bacterial biofilms formed on carbon steel coupons using reactors containing produced water from a Brazilian oil platform. Three independent experiments were carried out (E1, E2 and E3) using the same experimental conditions and different incubation times (5, 45 and 80 days, respectively). In every experiment, two biofilm-reactors were operated: one was treated with continuous nitrate flow (N reactor), and the other was a control reactor without nitrate (C reactor). A Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis approach using the 16S rRNA gene was performed to compare the bacterial groups involved in biofilm formation in the N and C reactors. DGGE profiles showed remarkable changes in community structure only in experiments E2 and E3. Five bands extracted from the gel that represented the predominant bacterial groups were identified as Bacillus aquimaris, B. licheniformis, Marinobacter sp., Stenotrophomonas maltophilia and Thioclava sp. A reduction in the sulfate-reducing bacteria (SRB) most probable number counts was observed only during the longer nitrate treatment (E3). Carbon steel coupons used for biofilm formation had a slightly higher weight loss in N reactors in all experiments. When the coupon surfaces were analysed by scanning electron microscopy, an increase in corrosion was observed in the N reactors compared with the C reactors. In conclusion, nitrate reduced the viable SRB counts. Nevertheless, the nitrate dosing increased the pitting of coupons. PMID:22806109

Marques, Joana Montezano; de Almeida, Fernando Pereira; Lins, Ulysses; Seldin, Lucy; Korenblum, Elisa

2012-06-01

211

Exploring nicotinamide cofactor promiscuity in NAD(P)H-dependent flavin containing monooxygenases (FMOs) using natural variation within the phosphate binding loop. Structure and activity of FMOs from Cellvibrio sp. BR and Pseudomonas stutzeri NF13  

PubMed Central

Flavin-containing monooxygenases (FMOs) catalyse asymmetric oxidation reactions that have potential for preparative organic synthesis, but most use the more expensive, phosphorylated nicotinamide cofactor NADPH to reduce FAD to FADH2 prior to formation of the (hydro)peroxy intermediate required for substrate oxygenation. A comparison of the structures of NADPH-dependent FMO from Methylophaga aminisulfidivorans (mFMO) and SMFMO from Stenotrophomonas maltophilia, which is able to use both NADPH and NADH, suggested that the promiscuity of the latter enzyme may be due in part to the substitution of an ArgThr couple in the NADPH phosphate recognition site in mFMO, for a GlnHis couple in SMFMO (Jensen et al., 2012, Chembiochem, 13, 872878). Natural variation within the phosphate binding region, and its influence on nicotinamide cofactor promiscuity, was explored through the cloning, expression, characterisation and structural studies of FMOs from Cellvibrio sp. BR (CFMO) and Pseudomonas stutzeri NF13 (PSFMO), which possess ThrSer and GlnGlu in the putative phosphate recognition positions, respectively. CFMO and PSFMO displayed 5- and 1.5-fold greater activity, respectively, than SMFMO for the reduction of FAD with NADH, and were also cofactor promiscuous, displaying a ratio of activity with NADH:NADPH of 1.7:1 and 1:1.3, respectively. The structures of CFMO and PSFMO revealed the context of the phosphate binding loop in each case, and also clarified the structure of the mobile helixloophelix motif that appears to shield the FAD-binding pocket from bulk solvent in this class of FMOs, a feature that was absent from the structure of SMFMO. PMID:25383040

Jensen, Chantel N.; Ali, Sohail T.; Allen, Michael J.; Grogan, Gideon

2014-01-01

212

Plasmid-mediated high-level gentamicin resistance among enteric bacteria isolated from pet turtles in Louisiana.  

PubMed

The sale of small turtles is banned by the Food and Drug Administration from the U.S. market due to concerns about their excretion of Salmonella spp. To produce a safe pet for the export market, the Louisiana pet turtle industry uses gentamicin sulfate baths (1,000 microg/ml) to eradicate Salmonella spp. from turtle eggs. In 1999, we analyzed bacterial samples recovered from turtle farms and found that strains of Salmonella enterica subsp. arizonae and other bacteria, such as Enterobacter cloacae, Citrobacter freundii, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia, were resistant to high concentrations of gentamicin (>2,000 microg/ml) and to other aminoglycosides. The goal of this study was to identify the gene(s) which contributes to the high-level gentamicin resistance phenotype observed in bacteria from environmental samples with turtle farming activity, particularly the salmonellae, and to estimate the incidence of such genes in these bacteria. R plasmids from gentamicin-resistant strains were transferred by conjugation and transformation to naive Escherichia coli cells. Cloning and sequencing of the gentamicin resistance determinants on these plasmids revealed the presence of the aminoglycoside acetyltransferase genes aac(3)-IIa and aac(3)-VIa; the latter was present as a gene cassette of a class 1 integron. Multiplex PCR assays showed that every gentamicin-resistant isolate carried one of these acetyltransferase genes. Pulsed-field gel electrophoresis and restriction enzyme digestion analysis of R plasmids carrying these genes revealed different restriction profiles and sizes, indicating a dissemination of the gentamicin resistance genes through mobile molecular elements. The data presented highlight the need to develop an alternate method for the eradication of Salmonella spp. from turtle eggs. PMID:16391058

Daz, Mara Alejandra; Cooper, Richard Kent; Cloeckaert, Axel; Siebeling, Ronald John

2006-01-01

213

Matrix-assisted laser desorption ionization-time of flight mass spectrometry for identification of nonfermenting gram-negative bacilli isolated from cystic fibrosis patients.  

PubMed

The identification of nonfermenting gram-negative bacilli isolated from cystic fibrosis (CF) patients is usually achieved by using phenotype-based techniques and eventually molecular tools. These techniques remain time-consuming, expensive, and technically demanding. We used a method based on matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) for the identification of these bacteria. A set of reference strains belonging to 58 species of clinically relevant nonfermenting gram-negative bacilli was used. To identify peaks discriminating between these various species, the profile of 10 isolated colonies obtained from 10 different passages was analyzed for each referenced strain. Conserved peaks with a relative intensity greater than 0.1 were retained. The spectra of 559 clinical isolates were then compared to that of each of the 58 reference strains as follows: 400 Pseudomonas aeruginosa, 54 Achromobacter xylosoxidans, 32 Stenotrophomonas maltophilia, 52 Burkholderia cepacia complex (BCC), 1 Burkholderia gladioli, 14 Ralstonia mannitolilytica, 2 Ralstonia pickettii, 1 Bordetella hinzii, 1 Inquilinus limosus, 1 Cupriavidus respiraculi, and 1 Burkholderia thailandensis. Using this database, 549 strains were correctly identified. Nine BCC strains and one R. mannnitolilytica strain were identified as belonging to the appropriate genus but not the correct species. We subsequently engineered BCC- and Ralstonia-specific databases using additional reference strains. Using these databases, correct identification for these species increased from 83 to 98% and from 94 to 100% of cases, respectively. Altogether, these data demonstrate that, in CF patients, MALDI-TOF-MS is a powerful tool for rapid identification of nonfermenting gram-negative bacilli. PMID:18685005

Degand, Nicolas; Carbonnelle, Etienne; Dauphin, Brunhilde; Beretti, Jean-Luc; Le Bourgeois, Muriel; Sermet-Gaudelus, Isabelle; Segonds, Christine; Berche, Patrick; Nassif, Xavier; Ferroni, Agns

2008-10-01

214

Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identification of Nonfermenting Gram-Negative Bacilli Isolated from Cystic Fibrosis Patients?  

PubMed Central

The identification of nonfermenting gram-negative bacilli isolated from cystic fibrosis (CF) patients is usually achieved by using phenotype-based techniques and eventually molecular tools. These techniques remain time-consuming, expensive, and technically demanding. We used a method based on matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) for the identification of these bacteria. A set of reference strains belonging to 58 species of clinically relevant nonfermenting gram-negative bacilli was used. To identify peaks discriminating between these various species, the profile of 10 isolated colonies obtained from 10 different passages was analyzed for each referenced strain. Conserved peaks with a relative intensity greater than 0.1 were retained. The spectra of 559 clinical isolates were then compared to that of each of the 58 reference strains as follows: 400 Pseudomonas aeruginosa, 54 Achromobacter xylosoxidans, 32 Stenotrophomonas maltophilia, 52 Burkholderia cepacia complex (BCC), 1 Burkholderia gladioli, 14 Ralstonia mannitolilytica, 2 Ralstonia pickettii, 1 Bordetella hinzii, 1 Inquilinus limosus, 1 Cupriavidus respiraculi, and 1 Burkholderia thailandensis. Using this database, 549 strains were correctly identified. Nine BCC strains and one R. mannnitolilytica strain were identified as belonging to the appropriate genus but not the correct species. We subsequently engineered BCC- and Ralstonia-specific databases using additional reference strains. Using these databases, correct identification for these species increased from 83 to 98% and from 94 to 100% of cases, respectively. Altogether, these data demonstrate that, in CF patients, MALDI-TOF-MS is a powerful tool for rapid identification of nonfermenting gram-negative bacilli. PMID:18685005

Degand, Nicolas; Carbonnelle, Etienne; Dauphin, Brunhilde; Beretti, Jean-Luc; Le Bourgeois, Muriel; Sermet-Gaudelus, Isabelle; Segonds, Christine; Berche, Patrick; Nassif, Xavier; Ferroni, Agns

2008-01-01

215

Microbial contamination of glaucoma eyedrops used by patients compared with ocular medications used in the hospital.  

PubMed

The aim of this study was to compare the percentage of contamination of multiuse eyedrops applied by glaucoma patients at home and by the medical personnel at the outpatient department, the ward, and the operating room of our Department of Ophthalmology.Eyedrops were collected over a period of 11 months. Samples were taken from the dropper tip (smear), drops, and the residual fluid inside the bottle and cultivated on blood agar. Colony forming units were counted and identified by mass spectrometry.The percentage of contamination was significantly higher in eyedrops applied by the patients (29/119; 24.4%, P?Stenotrophomonas maltophilia, and Staphylococcus aureus) were found only in 6 bottles (1.5%), whereas most of the detected microbes belonged to human or environmental flora.This study underlines the importance of hygienic handling of eyedrops and raises the question of whether single-use glaucoma medication might be preferred to reduce the risk of contamination. PMID:25715262

Teuchner, Barbara; Wagner, Julia; Bechrakis, Nikolaos E; Orth-Hller, Dorothea; Nagl, Markus

2015-02-01

216

Insight into the role of substrate-binding residues in conferring substrate specificity for the multifunctional polysaccharide lyase Smlt1473.  

PubMed

Anionic polysaccharides are of growing interest in the biotechnology industry due to their potential pharmaceutical applications in drug delivery and wound treatment. Chemical composition and polymer length strongly influence the physical and biological properties of the polysaccharide and thus its potential industrial and medical applications. One promising approach to determining monomer composition and controlling the degree of polymerization involves the use of polysaccharide lyases, which catalyze the depolymerization of anionic polysaccharides via a ?-elimination mechanism. Utilization of these enzymes for the production of custom-made oligosaccharides requires a high degree of control over substrate specificity. Previously, we characterized a polysaccharide lyase (Smlt1473) from Stenotrophomonas maltophilia k279a, which exhibited significant activity against hyaluronan (HA), poly-?-d-glucuronic acid (poly-GlcUA), and poly-?-d-mannuronic acid (poly-ManA) in a pH-regulated manner. Here, we utilize a sequence structure guided approach based on a homology model of Smlt1473 to identify nine putative substrate-binding residues and examine their effect on substrate specificity via site-directed mutagenesis. Interestingly, single point mutations H221F and R312L resulted in increased activity and specificity toward poly-ManA and poly-GlcUA, respectively. Furthermore, a W171A mutant nearly eliminated HA activity, while increasing poly-ManA and poly-GlcUA activity by at least 35%. The effect of these mutations was analyzed by comparison with the high resolution structure of Sphingomonas sp. A1-III alginate lyase in complex with poly-ManA tetrasaccharide and by taking into account the structural differences between HA, poly-GlcUA, and poly-ManA. Overall, our results demonstrate that even minor changes in active site architecture have a significant effect on the substrate specificity of Smlt1473, whose structural plasticity could be applied to the design of highly active and specific polysaccharide lyases. PMID:24808176

MacDonald, Logan C; Berger, Bryan W

2014-06-27

217

Additional observations and notes on the natural history of the prairie rattlesnake (Crotalus viridis) in Colorado.  

PubMed

On account of their unique anatomy, physiology, natural history, ecology, and behavior, rattlesnakes make ideal subjects for a variety of different scientific disciplines. The prairie rattlesnake (Crotalus viridis) in Colorado was selected for investigation of its relationship to colonies of black-tailed prairie dogs (Cynomys ludovicianus) with regard to spatial ecology. A total of 31 snakes were anesthetized and had radiotransmitters surgically implanted. In addition, at the time of their capture, all snakes underwent the following: (1) they had bacterial culture taken from their mouths for potential isolation of pathogenic bacteria; (2) similarly, they had cloacal bacterial cultures taken to assess potentially harmful bacteria passed in the feces; and (3) they had blood samples drawn to investigate the presence of any zoonotic agents in the serum of the snakes. The results of the study and their implications are discussed here. Traditionally, a low incidence of bacterial wound infection has been reported following snakebite. Nevertheless, the oral cavity of snakes has long been known to house a wide variety of bacterial flora. In our study, 10 different bacterial species were isolated from the mouths of the rattlesnakes, 6 of which are capable of being zoonotic pathogens and inducing human disease. More studies are necessary to see why more rattlesnake bites do not become infected despite the presence of such pathogenic bacteria. The results of fecal bacteria isolated revealed 13 bacterial species, 12 of which can cause disease in humans. Of the snakes whose samples were cultured, 26% were positive for the presence of the pathogen Salmonella arizonae, one of the causative agents of reptile-related salmonellosis in humans. It has long been reported that captive reptiles have a much higher incidence than wild, free-ranging species. This study shows the incidence of Salmonella in a wild, free-ranging population of rattlesnakes. In addition, Stenotrophomonas maltophilia was isolated. This bacterium is associated with wound and soft tissue infections that can lead to sepsis, endocarditis, meningitis, and peritonitis. In addition, this bacterium has been increasingly implicated as an opportunistic pathogen to humans during pregnancies, hospitalizations, malignancies and chemotherapy, chronic respiratory diseases, and presurgical endotracheal intubation. Furthermore, S. maltophilia has an intense resistance to broad-spectrum antibiotics, the results of our study showed the bacterium was resistant to multiple antibiotics. Our results indicate that anyone working with snake feces, dead skin, or their carcasses must follow reasonable hygiene protocols. Rattlesnakes tested for West Nile antibodies had positive results but these were invalidated owing to possible cross-reactivity with other unknown viruses, interference with snake serum proteins, and the fact that the test was not calibrated for rattlesnake serum. Still, the interesting implication remains, should we be regularly testing these animals as sentinels against potentially zoonotic diseases. The results of this study clearly show the value of veterinarians in a multidisciplinary study of this sort and the particular skill set they can offer. Veterinarians must get involved in conservation studies if the biodiversity of the planet is to be preserved. PMID:24331557

Fitzgerald, Kevin T; Shipley, Bryon K; Newquist, Kristin L; Vera, Rebecca; Flood, Aryn A

2013-11-01

218

Update on Acinetobacter species: mechanisms of antimicrobial resistance and contemporary in vitro activity of minocycline and other treatment options.  

PubMed

Among Acinetobacter species, A. baumannii and other closely related species are commonly implicated in nosocomial infections. These organisms are usually multidrug resistant (MDR), and therapeutic options to treat A. baumannii infections are very limited. Clinicians have been resorting to older antimicrobial agents to treat infections caused by MDR A. baumannii, and some of these agents have documented toxicity and/or are not optimized for the infection type to be treated. Recent clinical experience supported by antimicrobial susceptibility data suggests that minocycline has greater activity than other tetracyclines and glycylcyclines against various MDR pathogens that have limited therapeutic options available, including Acinetobacter species. An intravenous formulation of minocycline has recently become available for clinical use, and in contrast to most older tetracyclines, minocycline has high activity against Acinetobacter species. In this report, we summarized some of the characteristics of the tetracycline class, and quantified the minocycline activity against contemporary (2007-2011) isolates and its potential therapeutic role against a collection of 5477 A. baumannii and other relevant gram-negative organisms when compared directly with tetracycline, doxycycline, and other broad-spectrum antimicrobial agents. Acinetobacter baumannii strains were highly resistant to all agents tested, with the exception of minocycline (79.1% susceptible) and colistin (98.8% susceptible). Minocycline (minimum inhibitory concentration that inhibits 50% and 90% of the isolates [MIC(50/90)]: 1/8 g/mL) displayed greater activity than doxycycline (MIC(50/90): 2/>8 g/mL) and tetracycline hydrochloride (HCL) (only 30.2% susceptible) against A. baumannii isolates, and was significantly more active than other tetracyclines against Burkholderia cepacia, Escherichia coli, Serratia marcescens, and Stenotrophomonas maltophilia isolates. In vitro susceptibility testing using tetracycline HCL as a surrogate for the susceptibility other tetracyclines fails to detect minocycline-susceptible isolates and the potential utility of minocycline for the treatment of many MDR A. baumannii infections and other difficult-to-treat species, where there are often limited choices of antimicrobials. PMID:25371512

Castanheira, Mariana; Mendes, Rodrigo E; Jones, Ronald N

2014-12-01

219

Microbial profile and antibiotic sensitivity pattern in bile cultures from endoscopic retrograde cholangiography patients  

PubMed Central

AIM: To identify the frequency of bacterial growth, the most commonly grown bacteria and their antibiotic susceptibility, and risk factors for bacterial colonization in bile collected from patients with different biliary diseases. METHODS: This prospective study was conducted between April 2010 and August 2011. Patients with various biliary disorders were included. Bile was aspirated by placing a single-use, 5F, standard sphincterotome catheter into the bile duct before the injection of contrast agent during endoscopic retrograde cholangiopancreaticography (ERCP). Bile specimens were transported to the microbiology laboratory in blood culture bottles within an anaerobic transport system. Bacteria were cultured and identified according to the standard protocol used in our clinical microbiology laboratory. The susceptibilities of the organisms recovered were identified using antimicrobial disks, chosen according to the initial gram stain of the positive cultures. RESULTS: Ninety-one patients (27% male, mean age 53.7 17.5 years, range: 17-86 years) were included in the study. The main indication for ERCP was benign biliary disease in 79 patients and malignant disease in 12 patients. The bile culture was positive for bacterial growth in 46 out of 91 (50.5%) patients. The most frequently encountered organisms were Gram-negative bacteria including Escherichia coli (28.2%), Pseudomonas (17.3%) and Stenotrophomonas maltophilia (15.2%). There were no significant differences between patients with malignant and benign disease (58% vs 49%, P = 0.474), patients with acute cholangitis and without acute cholangitis (52.9% vs 50%, P = 0.827), patients who were empirically administered antibiotics before intervention and not administered (51.4% vs 60.7%, P = 0.384), with regard to the bacteriobilia. We observed a large covering spectrum or low resistance to meropenem, amikacin and imipenem. CONCLUSION: We did not find a significant risk factor for bacteriobilia in patients with biliary obstruction. A bile sample for microbiological analysis may become a valuable diagnostic tool as it leads to more accurate selection of antibiotics for the treatment of cholangitis. PMID:22826624

Kaya, Muhsin; Be?ta?, Remzi; Bacalan, Fatma; Bacaks?z, Ferhat; Arslan, Esma Glsun; Kaplan, Mehmet Ali

2012-01-01

220

Exposure to bioaerosols in a municipal sewage treatment plant.  

PubMed

Microbiological air sampling was performed in a medium-size sewage treatment plant processing municipal wastewater from a city located in eastern Poland. Air samples for determination of the concentrations of viable mesophilic bacteria, Gram-negative bacteria, thermophilic actinomycetes, fungi and endotoxin were collected at 12 sites associated with various phases of sewage treatment process. The concentrations of total mesophilic bacteria (both Gram-positive and Gram-negative) were within a range of 2.4-70.7 x 10(2) cfu/m(3). Gram-positive coryneform bacteria and cocci were dominant, forming respectively 56.6 % and 24.0 % of the total count. The concentrations of Gram-negative bacteria, thermophilic actinomycetes, and fungi were respectively within ranges of 0.2-5.7 x 10(2) cfu/m(3), 0-0.5 x 10(2) cfu/m(3), and 0.24-1.4 x 10(2) cfu/m(3). Among Gram-negative bacteria, commonly occurred Enterobacter cloacae (17.3 % of the total count), followed by Acinetobacter calcoaceticus (16.2 %), Pseudomonas spp. (14.0 %) and Stenotrophomonas maltophilia (11.1 %). Among thermophilic actinomycetes prevailed Thermoactinomyces thalpophilus (47.2 %) and Thermoactinomyces vulgaris (22.2 %), while among fungi, Geotrichum candidum (32.2 %), Penicillium spp. (20 %), Cladosporium lignicola (12.2 %), and Alternaria alternata (10.4 %). Altogether, 20 potentially pathogenic species or genera of bacteria and fungi were identified in the air samples taken in the examined plant. The values of the respirable fraction of airborne microflora varied within a fairly wide range and were between 24.1-100 %. The concentrations of airborne endotoxin were in the range of 0.104-5.2 ng/m(3). In conclusion, the concentrations of microorganisms and endotoxin in the examined municipal sewage treatment plant were low and did not exceed proposed occupational exposure limit values. A moderate risk for the workers may be associated with the presence of potentially pathogenic microbial species having allergenic and/or immunotoxic properties. PMID:14677919

Prazmo, Zofia; Krysinska-Traczyk, Ewa; Skorska, Czeslawa; Sitkowska, Jolanta; Cholewa, Grazyna; Dutkiewicz, Jacek

2003-01-01

221

Multispecies Biofilm Development on Space Station Heat Exhanger Core Material  

NASA Technical Reports Server (NTRS)

Investigations of microbial contamination of the cooling system aboard the International Space Station (ISS) suggested that there may be a relationship between heat exchanger (HX) materials and the degree of microbial colonization and biofilm formation. Experiments were undertaken to test the hypothesis that biofilm formation is influenced by the type and previous exposure of HX surfaces. Acidovorax delafieldii, Comamonas acidovorans, Hydrogenophaga pseudoflava, Pseudomonas stutzeri, Sphingomonas paucimobilis, and Stenotrophomonas maltophilia, originally isolated from ISS cooling system fluid, were cultured on R2A agar and suspended separately in fresh filter-sterilized ISS cooling fluid, pH 8.3. Initial numbers in each suspension ranged from 10(exp 6)-10(exp 7) CFU/ml, and a mixture contained greater than 10(exp 7) CFU/ml. Coupons of ISS HX material, previously used on orbit (HXOO) or unused (HXUU), polycarbonate (PC) and 316L polished stainless steel (SS) were autoclaved, covered with multispecies suspension in sterile tubes and incubated in the dark at ambient (22-25 C). Original HX material contained greater than 90% Ni, 4.5% Si, and 3.2% B, with a borate buffer. For approximately 10 weeks, samples of fluid were plated on R2A agar, and surface colonization assessed by SYBR green or BacLight staining and microscopy. Suspension counts for the PC and SC samples remained steady at around 10(exp 7) CFU/ml. HXUU counts declined about 1 log in 21 d then remained steady, and HXOO counts declined 2 logs in 28 d, fluctuated and stabilized about 10(exp 3) CFU/ml from 47-54 d. Predominantly yellow S. paucimobilis predominated on plates from HXOO samples up to 26 d, then white or translucent colonies of other species appeared. All colony types were seen on plates from other samples throughout the trial. Epifluorescence microscopy indicated microbial growth on all surfaces by 21 d, followed by variable colonization. After 54 d, all but the HXOO samples had well-distributed live and dead cells; the HXOO samples had few cells and most were live by BacLight. The results suggest that HX materials themselves are inhibiting microbial growth on the surfaces. The HX exposed on orbit to cooling system fluid inhibited growth of some species originally isolated from the system, whereas the unused HX material had a moderate effect compared to no inhibition with PC or SS controls. It is possible that chemistry or microbiology of the ISS system increased deposition of inhibitory compounds on the HXOO coupon surfaces; these may inhibit inoculated species to differing degrees.

Pyle, B. H.; Roth, S. R.; Vega, L. M.; Pickering, K. D.; Alvarez, Pedro J. J.; Roman, M. C.

2007-01-01

222

In vitro antibacterial spectrum of a new broad-spectrum 8-methoxy fluoroquinolone, gatifloxacin.  

PubMed

The in vitro antibacterial spectrum of gatifloxacin was compared with those of ciprofloxacin and ofloxacin. Gatifloxacin was two- to four-fold more potent than comparator quinolones against staphylococci, streptococci, pneumococci and enterococci (gatifloxacin MIC90s, < or =1 mg/L, except 4 mg/L against methicillin-resistant Staphylococcus aureus and Enterococcus faecium). Gatifloxacin was two-fold less potent than ciprofloxacin, and the same as or two-fold more potent than ofloxacin against Enterobacteriaceae (MIC90s, 0.06-0.5 mg/L against most members of the Enterobacteriaceae and < or =1 mg/L against Proteus/Morganella spp.). Relative to the comparator quinolones, gatifloxacin was two- to four-fold more potent against Providencia spp., and had good potency against Acinetobacter spp. (MIC90s, 0.25-1 mg/L). Gatifloxacin and ofloxacin had similar anti-pseudomonal potency, with corresponding MIC90s of 4, 8 and 0.25 mg/L for Pseudomonas aeruginosa, Pseudomonas fluorescens and Pseudomonas stutzeri, while ciprofloxacin had two- to eight-fold more potency. The three quinolones were equipotent against Burkholderia cepacia (MIC90s, 8 mg/L), but gatifloxacin was two-fold more potent against Stenotrophomonas maltophilia (MIC90, 4 mg/L). Gatifloxacin was highly potent (MIC90s, 0.03-0.06 mg/L) against Haemophilus influenzae, Legionella spp., Helicobacter pylori and had at least eight-fold better anti-chlamydial and anti-mycoplasma potency (gatifloxacin MIC90s, 0.13 mg/L). The higher quinolone MICs for ureaplasma (MIC90s, 4-8 mg/L) may be due to the acidic pH of the ureaplasma test medium, which antagonizes quinolones. Like other quinolones, gatifloxacin had poor potency against Mycobacterium avium-intracellulare, though it was eight- to 16-fold more potent against Mycobacterium tuberculosis (MIC90, 0.25 mg/L). Of the three quinolones, only gatifloxacin had activity against Bacteroides fragilis and Clostridium difficile. In summary, gatifloxacin is a broad-spectrum 8-methoxy fluoroquinolone that is more potent than ciprofloxacin and ofloxacin against Gram-positive bacteria, chlamydia, mycoplasma, mycobacteria and anaerobes. PMID:10747819

Fung-Tomc, J; Minassian, B; Kolek, B; Washo, T; Huczko, E; Bonner, D

2000-04-01

223

Ceftolozane/tazobactam activity tested against Gram-negative bacterial isolates from hospitalised patients with pneumonia in US and European medical centres (2012).  

PubMed

During 2012, a total of 2968 isolates were consecutively collected from 59 medical centres in the USA and 15 European countries from hospitalised patients with pneumonia. Ceftolozane/tazobactam (tazobactam at a fixed concentration of 4mg/L) and comparator agents were tested by reference methods, and MIC endpoints were interpreted by CLSI (2013) and EUCAST (2013) breakpoint criteria. Pseudomonas aeruginosa was the most common isolated pathogen (1019 strains; 34.3%), and ceftolozane/tazobactam was the most active ?-lactam tested against P. aeruginosa (MIC50/90, 0.5/4 mg/L; 94.1% inhibited at ? 8 mg/L). P. aeruginosa exhibited moderate susceptibility to meropenem (MIC50/90, 0.5/>8 mg/L; 73.7% susceptible), ceftazidime (MIC50/90, 2/>32 mg/L; 73.6% susceptible), cefepime (MIC50/90, 4/>16 mg/L; 76.5% susceptible), piperacillin/tazobactam (MIC50/90, 8/>64 mg/L; 69.5% susceptible), levofloxacin [MIC50/90, 0.5/>4 mg/L; 69.9/61.0% susceptible (CLSI/EUCAST criteria)] and gentamicin (MIC50/90, 2/>8 mg/L; 80.7% susceptible). Ceftolozane/tazobactam exhibited activity against many ceftazidime-non-susceptible, meropenem-non-susceptible and piperacillin/tazobactam-non-susceptible, multidrug-resistant (MDR) and extensively drug-resistant (XDR) P. aeruginosa isolates. Ceftolozane/tazobactam was active (MIC50/90, 0.25/4mg/L; 94.6% inhibited at ? 8 mg/L) against 1530 Enterobacteriaceae, including activity against many MDR and XDR strains. MDR and XDR prevalence varied widely between countries both for P. aeruginosa (24.1% MDR and 17.1% XDR overall) and Enterobacteriaceae (15.4% MDR and 2.7% XDR overall). All ?-lactams had limited activity against Acinetobacter spp. and Stenotrophomonas maltophilia. Ceftolozane/tazobactam demonstrated greater in vitro activity than currently available cephalosporins, carbapenems and piperacillin/tazobactam when tested against P. aeruginosa. In addition, ceftolozane/tazobactam demonstrated greater activity than contemporary cephalosporins and piperacillin/tazobactam when tested against most Enterobacteriaceae. PMID:24856078

Farrell, David J; Sader, Helio S; Flamm, Robert K; Jones, Ronald N

2014-06-01

224

antibacTR: dynamic antibacterial-drug-target ranking integrating comparative genomics, structural analysis and experimental annotation  

PubMed Central

Background Development of novel antibacterial drugs is both an urgent healthcare necessity and a partially neglected field. The last decades have seen a substantial decrease in the discovery of novel antibiotics, which combined with the recent thrive of multi-drug-resistant pathogens have generated a scenario of general concern. The procedures involved in the discovery and development of novel antibiotics are economically challenging, time consuming and lack any warranty of success. Furthermore, the return-on-investment for an antibacterial drug is usually marginal when compared to other therapeutics, which in part explains the decrease of private investment. Results In this work we present antibacTR, a computational pipeline designed to aid researchers in the selection of potential drug targets, one of the initial steps in antibacterial-drug discovery. The approach was designed and implemented as part of two publicly funded initiatives aimed at discovering novel antibacterial targets, mechanisms and drugs for a priority list of Gram-negative pathogens: Acinetobacter baumannii, Escherichia coli, Helicobacter pylori, Pseudomonas aeruginosa and Stenotrophomonas maltophilia. However, at present this list has been extended to cover a total of 74 fully sequenced Gram-negative pathogens. antibacTR is based on sequence comparisons and queries to multiple databases (e.g. gene essentiality, virulence factors) to rank proteins according to their potential as antibacterial targets. The dynamic ranking of potential drug targets can easily be executed, customized and accessed by the user through a web interface which also integrates computational analyses performed in-house and visualizable on-site. These include three-dimensional modeling of protein structures and prediction of active sites among other functionally relevant ligand-binding sites. Conclusions Given its versatility and ease-of-use at integrating both experimental annotation and computational analyses, antibacTR may effectively assist microbiologists, medicinal-chemists and other researchers working in the field of antibacterial drug-discovery. The public web-interface for antibacTR is available at http://bioinf.uab.cat/antibactr. PMID:24438389

2014-01-01

225

In vitro activity of ceftaroline against gram-positive and gram-negative pathogens isolated from patients in Canadian hospitals in 2009.  

PubMed

The in vitro activities of ceftaroline and comparative agents were determined for a collection of the most frequently isolated bacterial pathogens from hospital-associated patients across Canada in 2009 as part of the ongoing CANWARD surveillance study. In total, 4,546 isolates from 15 sentinel Canadian hospital laboratories were tested using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method. Compared with other cephalosporins, including ceftobiprole, cefepime, and ceftriaxone, ceftaroline exhibited the greatest potency against methicillin-susceptible Staphylococcus aureus (MSSA), with a MIC?? of 0.25 ?g/ml. Ceftaroline also demonstrated greater potency than ceftobiprole against community-associated methicillin-resistant S. aureus (MRSA) (MIC??, 0.5 ?g/ml) and health care-associated MRSA (MIC??, 1 ?g/ml) and was at least 4-fold more active than other cephalosporins against Staphylococcus epidermidis; all isolates of MSSA and MRSA tested were susceptible to ceftaroline (MIC, ?1 ?g/ml). Against streptococci, including Streptococcus pneumoniae, ceftaroline MICs (MIC??, ?0.03 ?g/ml) were comparable to those of ceftobiprole; however, against penicillin-nonsusceptible, macrolide-nonsusceptible, and multidrug-nonsusceptible isolates of S. pneumoniae, ceftaroline demonstrated 2- to 4-fold and 4- to 16-fold more potent activities than those of ceftobiprole and ceftriaxone, respectively. All isolates of S. pneumoniae tested were susceptible to ceftaroline (MIC, ?0.25 ?g/ml). Among Gram-negative isolates, ceftaroline demonstrated potent activity (MIC??, ?0.5 ?g/ml) against Escherichia coli (92.2% of isolates were susceptible), Klebsiella pneumoniae (94.1% of isolates were susceptible), Proteus mirabilis (97.7% of isolates were susceptible), and Haemophilus influenzae (100% of isolates were susceptible). Ceftaroline demonstrated less potent activity (MIC??, ?4 ?g/ml) against Enterobacter spp., Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella oxytoca, Serratia marcescens, and Stenotrophomonas maltophilia. Overall, ceftaroline demonstrated potent in vitro activity against a recent collection of the most frequently encountered Gram-positive and Gram-negative isolates from patients attending hospitals across Canada in 2009. PMID:21402844

Karlowsky, James A; Adam, Heather J; Decorby, Melanie R; Lagac-Wiens, Philippe R S; Hoban, Daryl J; Zhanel, George G

2011-06-01

226

Ceftobiprole activity against over 60,000 clinical bacterial pathogens isolated in Europe, Turkey, and Israel from 2005 to 2010.  

PubMed

Ceftobiprole medocaril is a newly approved drug in Europe for the treatment of hospital-acquired pneumonia (HAP) (excluding patients with ventilator-associated pneumonia but including ventilated HAP patients) and community-acquired pneumonia in adults. The aim of this study was to evaluate the in vitro antimicrobial activity of ceftobiprole against prevalent Gram-positive and -negative pathogens isolated in Europe, Turkey, and Israel during 2005 through 2010. A total of 60,084 consecutive, nonduplicate isolates from a wide variety of infections were collected from 33 medical centers. Species identification was confirmed, and all isolates were susceptibility tested using reference broth microdilution methods. Ceftobiprole had high activity against methicillin-susceptible Staphylococcus aureus (MSSA) (100.0% susceptible), methicillin-susceptible coagulase-negative staphylococci (CoNS), beta-hemolytic streptococci, and Streptococcus pneumoniae (99.3% susceptible), with MIC90 values of 0.25, 0.12, ? 0.06, and 0.5 ?g/ml, respectively. Ceftobiprole was active against methicillin-resistant S. aureus (MRSA) (98.3% susceptible) and methicillin-resistant CoNS, having a MIC90 of 2 ?g/ml. Ceftobiprole was active against Enterococcus faecalis (MIC50/90, 0.5/4 ?g/ml) but not against most Enterococcus faecium isolates. Ceftobiprole was very potent against the majority of Enterobacteriaceae (87.3% susceptible), with >80% inhibited at ? 0.12 ?g/ml. The potency of ceftobiprole against Pseudomonas aeruginosa (MIC50/90, 2/>8 ?g/ml; 64.6% at MIC values of ? 4 ?g/ml) was similar to that of ceftazidime (MIC50/90, 2/>16 ?g/ml; 75.4% susceptible), but limited activity was observed against Acinetobacter spp. and Stenotrophomonas maltophilia. High activity was also observed against all Haemophilus influenzae (MIC90, ? 0.06 ?g/ml) and Moraxella catarrhalis (MIC50/90, ? 0.06/0.25 ?g/ml) isolates. Ceftobiprole demonstrated a wide spectrum of antimicrobial activity against this very large longitudinal sample of contemporary pathogens. PMID:24777091

Farrell, David J; Flamm, Robert K; Sader, Helio S; Jones, Ronald N

2014-07-01

227

Characterization of N2O-producing Xanthomonas-like isolates from biofilters as Stenotrophomonas nitritireducens sp. nov., Luteimonas mephitis gen. nov., sp. nov. and Pseudoxanthomonas broegbernensis gen. nov., sp. nov  

Microsoft Academic Search

A group of yellow-pigmented isolates from ammonia-supplied biofilters showed an unusual denitrification reaction. All strains reduced nitrite but not nitrate without production of nitrogen (N2). The only product found was nitrous oxide (N2O). The strains were divided into two clusters and one separate strain by their fatty acid profiles, which were similar to the fatty acid profiles of the genera

Wolfgang Finkmann; Karlheinz Altendorf; Erko Stackebrandt

228

DataData Interpretation,MICs,ARInterpretation,MICs,AR andand I.M. GouldI.M. Gould  

E-print Network

Burkholderia Stenotrophomonas #12;E. coli: proportion of invasive isolates resistant to fluoroquinolones,5 10 Hours PAE Betalactams Linezolid Aminoglycosides Fluoroquinolones Daptomycin Vancomycin Teicoplanin

Glasgow, University of

229

MIXED-SPECIES COLONIZATION OF SOLID SURFACES IN LABORATORY BIOFILMS  

EPA Science Inventory

Colonization of glass substrata by populations of three or four bacterial species over periods of four weeks or more was investigated using recirculating, model laboratory systems. umbers of coryneform, Aeromonas hydrophile, Pseudomonas fluoresces, and Xanthomonas maltophilia on ...

230

Invitro evaluation of the probiotic and functional potential of Lactobacillus strains isolated from fermented food and human intestine.  

PubMed

This study aims to evaluate the functional and probiotic characteristics of eight indigenous Lactobacillus strains invitro. The selected lactobacilli include strains of Lactobacillus casei subsp. casei, Lactobacillus salivarius subsp. salicinius, Lactobacillus fermentum, Lactobacillus plantarum, Lactobacillus delbrueckii subsp. lactis, Lactobacillus delbrueckii subsp. bulgaricus, and Lactobacillus rhamnosus. All strains tolerated both pH 2 for 3h and 1% bile salt for 24h. The strains CICC 23174 and CGMCC 1.557 were the most adhesive strains producing the highest quantity of EPS. Although a wide variation in the ability of the eight strains to deplete cholesterol and nitrite, antagonize pathogens, scavenge free radical, and stimulate innate immune response were observed, the strains CICC 23174 and CGMCC 1.557 showed the widest range of these useful traits. Taken together, the strains CICC 23174 and CGMCC 1.557 exhibited the best probiotic properties with the potential for use in the production of probiotic fermented foods. PMID:25046742

Ren, Dayong; Li, Chang; Qin, Yanqing; Yin, Ronglan; Du, Shouwen; Ye, Fei; Liu, Cunxia; Liu, Hongfeng; Wang, Maopeng; Li, Yi; Sun, Yang; Li, Xiao; Tian, Mingyao; Jin, Ningyi

2014-12-01

231

Streptomyces ferrugineus sp. nov., isolated from mangrove soil in Thailand.  

PubMed

Bacterial strain HV38(T) was isolated from mangrove soil, which was collected from Thailand. Chemotaxonomic and morphological characteristics were found to be typical of members of the genus Streptomyces. The strain was found to form a distinct phyletic line in the Streptomyces 16S rRNA gene tree and to be closely associated with the type strains of Streptomyces coeruleofuscus CGMCC 4.1667(T) (98.84% sequence similarity), Streptomyces chromofuscus CGMCC 4.1451(T) (98.63%) and Streptomyces albidoflavus CGMCC 4.1291(T) (98.56%). The major menaquinones were identified as MK-9(H8) and MK-9(H10). Its major cellular fatty acids were found to be iso-C14:0, iso-C15:0, anteiso-C15:0, iso-C16:1?8c, C16:0, anteiso-C16:1?8c, iso-C16:0 and anteiso-C16:0. The DNA-DNA hybridization values between strain HV38(T) with S. coeruleofuscus CGMCC 4.1667(T), S. chromofuscus CGMCC 4.1451(T) and S. albidoflavus CGMCC 4.1291(T) were 32.70.9, 21.80.3 and 19.90.9%, respectively, which clearly supported the conclusion that they belong to separate genomic species. Cumulatively, the data indicated that strain HV38(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces ferrugineus sp. nov. is proposed. The type strain is HV38(T) (=CCTCC AA2014009(T)=DSM 42152(T)). PMID:25331336

Ruan, Chang-ying; Zhang, Li; Ye, Wan-wan; Xie, Xiu-chao; Srivibool, Rattanaporn; Duangmal, Kannika; Pathom-aree, Wasu; Deng, Zi-xin; Hong, Kui

2015-01-01

232

Complete Genome Sequence of the Metabolically Versatile Halophilic Archaeon Haloferax mediterranei, a Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) Producer  

PubMed Central

Haloferax mediterranei, an extremely halophilic archaeon, has shown promise for production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from unrelated cheap carbon sources. Here we report the complete genome (3,904,707 bp) of H. mediterranei CGMCC 1.2087, consisting of one chromosome and three megaplasmids. PMID:22843593

Han, Jing; Zhang, Fan; Hou, Jing; Liu, Xiaoqing; Li, Ming; Liu, Hailong; Cai, Lei; Zhang, Bing; Chen, Yaping; Zhou, Jian

2012-01-01

233

INFLUENCE OF SOLID SURFACE, ADHESIVE ABILITY, AND INOCULUM SIZE ON BACTERIAL COLONIZATION IN MICROCOSM STUDIES  

EPA Science Inventory

Microcosm studies were performed to evaluate the effect of solid surfaces, bacterial adhesive ability, and inoculum size on colonization success and persistence of P. fluorescens or X maltophilia, each with a Tn5 insertion that conferred resistance to kanamycin and streptomycin. ...

234

Microorganisms for degrading simmondsin and related cyanogenic toxins in jojoba  

Microsoft Academic Search

Four microorganisms that metabolize simmondsin (S) and related cyanogenic toxins from jojoba (Simmondsia chinensis) were isolated by enrichment: Pseudallescheria boydii, a fungus which specifically degrades simmondsin ferulate but not S; Fusarium moniliforme; Flavobacterium aurantiacum; and Pseudomonas maltophilia. The latter three organisms grow on S as a sole carbon and nitrogen source in culture media, but only F. moniliforme attacks S

Thomas P. Abbott; Lawrence K. Nakamura; Terry C. Nelsen; Helen J. Gasdorf; Glenn A. Bennett; Robert Kleiman

1990-01-01

235

Proposal to reclassify the Streptomyces albidoflavus clade on the basis of multilocus sequence analysis and DNADNA hybridization, and taxonomic elucidation of Streptomyces griseus subsp. solvifaciens  

Microsoft Academic Search

The Streptomyces albidoflavus 16S rRNA gene clade contains 10 species and subspecies with identical 16S rRNA gene sequences and very similar numerical taxonomic data, including Streptomyces griseus subsp. solvifaciens. Type strains of this clade, as well as three CGMCC strains which were received as Streptomyces galilaeus, Streptomyces sioyaensis and Streptomyces vinaceus, respectively, that shared the same 16S rRNA gene sequences

Xiaoying Rong; Yinping Guo; Ying Huang

2009-01-01

236

Complete genome sequence of Bifidobacterium adolesentis BBMN23, a probiotic strain from healthy centenarian.  

PubMed

Bifidobacterium adolesentis BBMN23 (CGMCC No. 2264) was a probiotic strain originated from the feces of a centenarian. It is an excellent model for the study of the adaptation of genus bifidobacteria to adult human gut, which is a key factor in bifidobacterial strains that allows them to persist in gut and become useful in the food and medical industries. In the present study the complete genome sequence of BBMN23 is presented to provide insight into this strain. PMID:25678139

Liu, Songling; Zhao, Liang; Ren, Fazheng; Sun, Erna; Zhang, Ming; Guo, Huiyuan

2015-03-20

237

Metabolic flux analysis of Gluconacetobacter xylinus for bacterial cellulose production.  

PubMed

Metabolic flux analysis was used to reveal the metabolic distributions in Gluconacetobacter xylinus (CGMCC no. 2955) cultured on different carbon sources. Compared with other sources, glucose, fructose, and glycerol could achieve much higher bacterial cellulose (BC) yields from G. xylinus (CGMCC no. 2955). The glycerol led to the highest BC production with a metabolic yield of 14.7g/mol C, which was approximately 1.69-fold and 2.38-fold greater than that produced using fructose and glucose medium, respectively. The highest BC productivity from G. xylinus CGMCC 2955 was 5.97g BC/L (dry weight) when using glycerol as the sole carbon source. Metabolic flux analysis for the central carbon metabolism revealed that about 47.96% of glycerol was transformed into BC, while only 19.05% of glucose and 24.78% of fructose were transformed into BC. Instead, when glucose was used as the sole carbon source, 40.03% of glucose was turned into the by-product gluconic acid. Compared with BC from glucose and fructose, BC from the glycerol medium showed the highest tensile strength at 83.5MPa, with thinner fibers and lower porosity. As a main byproduct of biodiesel production, glycerol holds great potential to produce BC with superior mechanical and microstructural characteristics. PMID:23640364

Zhong, Cheng; Zhang, Gui-Cai; Liu, Miao; Zheng, Xin-Tong; Han, Pei-Pei; Jia, Shi-Ru

2013-07-01

238

Marinobacter shengliensis sp. nov., a moderately halophilic bacterium isolated from oil-contaminated saline soil.  

PubMed

Two moderately halophilic strains, designated SL013A34A2(T) and SL013A24A, were isolated from oil-contaminated saline soil from Shengli Oilfield, eastern China. Cells were found to be Gram-staining negative, aerobic, rod-shaped with a single polar flagellum. The isolates were found to grow at 10-40C (optimum 35C), pH 6.0-9.0 (optimum pH 8.0), and NaCl concentrations of 0.5-18.0% (w/v) (optimum 3.0-6.0 NaCl). The 16S rRNA gene sequence analysis indicated that the isolates belong to the genus Marinobacter. Strain SL013A34A2(T) shares the highest 16S rRNA gene sequence similarities with strain SL013A24A (99.3%), followed by M. hydrocarbonoclasticus CGMCC 1.7683(T) (97.8%), M. vinifirmus CGMCC 1.7265(T) (97.8%), and M. excellens KMM 3809(T) (97.4%), respectively, but low similarities (93.8-96.4%) with type strains of the other numbers of genus Marinobacter. DNA-DNA relatedness values of strain SL013A34A2(T) with strains SL013A24A, M. hydrocarbonoclasticus CGMCC 1.7683(T), M. vinifirmus CGMCC 1.7265(T) and M. excellens KMM 3809(T) were 88.7, 29.2, 33.4 and 29.4%, respectively. The major fatty acids of strain SL013A34A2(T) were identified as C18:1 ?9c, C16:0, C12:03-OH, C12:0, C16:1 ?9c and 10-methyl C18:0. The major respiratory quinone of strain SL013A34A2(T) was found to be ubiquinone-9, and its predominant polar lipids were identified as diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and unidentified glycolipid. The genomic DNA G+C content was found to be 56.1mol%. Based on the phenotypic, genetic and chemotaxonomic characteristics, these two isolates are representatives of a novel species of the genus Marinobacter, for which the name Marinobacter shengliensis sp. nov. is proposed. The type strain is SL013A34A2(T)(=LMG 27740(T)=CGMCC 1.12758(T)). PMID:25652339

Luo, Yi-Jing; Xie, Bai-Sheng; Lv, Xiang-Lin; Cai, Man; Wang, Ya-Nan; Cui, Heng-Lin; Cai, Hua; Wu, Xiao-Lei

2015-04-01

239

Effects of different osmolarities on bacterial biofilm formation  

PubMed Central

Biofilm formation depends on several factors. The influence of different osmolarities on bacterial biofilm formation was studied. Two strains (Enterobacter sp. and Stenotrophomonas sp.) exhibited the most remarkable alterations. Biofilm formation is an important trait and its use has been associated to the protection of organisms against environmental stresses. PMID:25242950

Kavamura, Vanessa Nessner; de Melo, Itamar Soares

2014-01-01

240

Control of infection and sporulation of Botrytis cinerea on bean and tomato by saprophytic bacteria and fungi  

Microsoft Academic Search

Sixty isolates of saprophytic microorganisms were screened for their ability to reduce the severity of grey mould (Botrytis cinerea) infection and sporulation. Isolates of the bacteriaXanthomonas maltophilia, Bacillus pumilus, Lactobacillus sp., andPseudomonas sp. and the fungusGliocladium catenulatum reduced germination of conidia of the pathogen and controlled disease on bean and tomato plants. Their activity under growth room conditions was good,

Y. Elead; J. Khl; N. J. Fokkema

1994-01-01

241

Degradation of BTEX compounds in liquid media and in peat biofilters  

Microsoft Academic Search

A mixed culture, enriched from Sphagnum peat moss, contaminated with gasoline vapours, degraded individual and mixed components of BTEX (benzene, toluene, ethylbenzene, xylene). Complete degradation of radiolabelled toluene by the mixed culture was observed in mineralisation studies. Individual isolates from a mixed culture containingPseudomonas maltophilia, P. testosteroni andP. putida biotype A exhibited contrasting BTEX degradation patterns. WhileP. putida biotype A

A Mallakin; O P Ward

1996-01-01

242

Salinarubrum litoreum gen. nov., sp. nov.: a new member of the family Halobacteriaceae isolated from Chinese marine solar salterns.  

PubMed

Three halophilic archaeal strains, XD46(T), YJ-63-S1 and ZS-1-H, were isolated from three Chinese marine solar salterns. All were observed to have pleomorphic cells that lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. They were found to grow optimally at 37C, at pH 7.0 and in the presence of 2.6M NaCl and 0.05MMg(2+). The major polar lipids were identified as those typical for members of the Halobacteriaceae but also included major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1), mannosyl glucosyl diether (DGD-1) and two unidentified ones. The 16S rRNA gene sequences of the three strains were 99.8-100% identical, showing most similarity to sequences of members of the family Halobacteriaceae, and clustering together as a distinct clade in phylogenetic tree reconstructions. The rpoB' gene similarities between the three strains were 98.7-100% and lower to the sequences of other halobacteria. Their DNA G+C contents were determined to be 65.1-65.5mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains XD46(T) (=CGMCC 1.12237(T)=JCM 18649(T)), YJ-63-S1 (=CGMCC 1.12574) and ZS-1-H (=CGMCC 1.12544) represent a novel species in a new genus within the family Halobacteriaceae, for which the name Salinarubrum litoreum gen. nov., sp. nov. is proposed. PMID:24158535

Cui, Heng-Lin; Qiu, Xing-Xing

2014-01-01

243

Halorussus ruber sp. nov., isolated from an inland salt lake of China.  

PubMed

Halophilic archaeal strain YC25(T) was isolated from Yuncheng salt lake in Shanxi, China. Cells of strain YC25(T) were observed to be pleomorphic rods, stained Gram-negative, and formed red-pigmented colonies on solid media. Strain YC25(T) was found to be able to grow at 25-50C (optimum 37C), at 1.4-4.8M NaCl (optimum 1.7M), at 0-1.0M MgCl2 (optimum 0.01M), and at pH 5.5-9.0 (optimum pH 6.5). The cells lysed in distilled water, and the minimal NaCl concentration to prevent cell lysis was found to be 8% (w/v). The major polar lipids of the strain were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS), sulfated galactosyl mannosyl glucosyl diether (S-TGD-1), sulfated mannosyl glucosyl diether (S-DGD-1), galactosyl mannosyl glucosyl diether (TGD-1), mannosyl glucosyl diether (DGD-1), and an unknown diglycosyl diether (DGD-2) chromatographically identical to those of Halorussus rarus CGMCC 1.10122(T). The 16S rRNA gene and rpoB' gene of strain YC25(T) were phylogenetically related to the corresponding genes of Halorussus rarus CGMCC 1.10122(T) (94.3-95.4 and 91.5% nucleotide identity, respectively). The DNA G+C content of strain YC25(T) was determined to be 63.3mol%. The phenotypic, chemotaxonomic, and phylogenetic properties suggested that strain YC25(T) (=CGMCC 1.12122(T)=JCM 18363(T)) represents a new species of Halorussus, for which the name Halorussus ruber sp. nov. is proposed. PMID:25381138

Xu, Wei-Dong; Zhang, Wen-Jiao; Han, Dong; Cui, Heng-Lin; Yang, Kun

2015-01-01

244

Complete genome sequence of Bifidobacterium animalis subsp. lactis A6, a probiotic strain with high acid resistance ability.  

PubMed

Bifidobacterium animalis subsp. lactis A6 (BAA6) (CGMCC No. 9273) was a probiotic strain isolated from the feces of a centenarian. Previous study showed that BAA6 had high acid resistance to low pH which is a critical factor influencing its healthy benefits. Elaborating the stress resistant mechanisms of bifidobacteria is important to extensively exploit this probiotic. Here, we reported the complete genome sequence of BAA6 that contains 1,958,651bp encoding 1622 CDSs, 16 rRNA genes, 52 tRNA genes. PMID:25707999

Sun, Erna; Zhao, Liang; Ren, Fazheng; Liu, Songling; Zhang, Ming; Guo, Huiyuan

2015-04-20

245

Variation of nonylphenol-degrading gene abundance and bacterial community structure in bioaugmented sediment microcosm.  

PubMed

Nonylphenol (NP) can accumulate in river sediment. Bioaugmentation is an attractive option to dissipate heavy NP pollution in river sediment. In this study, two NP degraders were isolated from crude oil-polluted soil and river sediment. Microcosms were constructed to test their ability to degrade NP in river sediment. The shift in the proportion of NP-degrading genes and bacterial community structure in sediment microcosms were characterized using quantitative PCR assay and terminal restriction fragment length polymorphism analysis, respectively. Phylogenetic analysis indicated that the soil isolate belonged to genus Stenotrophomonas, while the sediment isolate was a Sphingobium species. Both of them could almost completely clean up a high level of NP in river sediment (150 mg/kg NP) in 10 or 14 days after inoculation. An increase in the proportion of alkB and sMO genes was observed in sediment microcosms inoculated with Stenotrophomonas strain Y1 and Sphingobium strain Y2, respectively. Moreover, bioaugmentation using Sphingobium strain Y2 could have a strong impact on sediment bacterial community structure, while inoculation of Stenotrophomonas strain Y1 illustrated a weak impact. This study can provide some new insights towards NP biodegradation and bioremediation. PMID:25277711

Wang, Zhao; Yang, Yuyin; Sun, Weimin; Dai, Yu; Xie, Shuguang

2015-02-01

246

Optimization of culture medium compositions for gellan gum production by a halobacterium Sphingomonas paucimobilis.  

PubMed

The effect of culture medium compositions on gellan gum production produced by fermentation with a halobacterium Sphingomonas paucimobilis QHZJUJW CGMCC2428 was studied. In this work, a fractional factorial design was applied to investigate the main factors that affected gellan gum production by S. paucimobilis QHZJUJW CGMCC2428. Sucrose was the best carbon source for gellan gum and peptone displayed better inducing effect. Central composite design and response surface methodology were adopted to derive a statistical model for optimizing submerged culture medium composition. These experimental results showed that the optimum culture medium for producing gellan gum was composed of 40.00 (w/v) sucrose, 3.00% peptone (w/v), MgSO4 (w/v), 9.20% KH2PO4 (w/v), 7.50% Na2HPO4 (w/v), 4.30% K2SO4 (w/v), pH 6.8-7.0. The maximal gellan gum was 19.890.68 g/L, which was agreed closely with the predicated value (20.12 g/L). After incubated for 72 h under the optimized culture medium in 5-L bioreactor, the gellan gum fermentation reached about 19.900.68 g/L, which was higher than that in the initial cultivation medium. PMID:25439950

Zhang, Jun; Dong, Ya-chen; Fan, Lin-lin; Jiao, Zhi-hua; Chen, Qi-he

2015-01-22

247

Halomonas caseinilytica sp. nov., a halophilic bacterium isolated from a saline lake on the Qinghai-Tibet Plateau, China.  

PubMed

A halophilic, Gram-negative bacterial strain, designated AJ261T, which was isolated from a soil sample from a salt lake on the Qinghai-Tibet Plateau, was subjected to a polyphasic taxonomic study. The isolate grew optimally in the presence of 3-5 % NaCl and used various carbohydrates as sole carbon and energy sources. The genomic DNA G+C content was 63.0 mol%. The predominant fatty acids were C18 : 1omega7c, C16 : 0 and C12 : 0. A phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate had the highest sequence similarity with respect to type strains of Halomonas elongata (98.2 %), Halomonas eurihalina (98.1 %) and Halomonas halmophila (97.2 %). The DNA-DNA relatedness of strain AJ261T with respect to H. elongata NBRC 15536T, H. eurihalina CGMCC 1.2318T and H. halmophila DSM 5349T was 42, 25 and 26 %, respectively. Overall, the phenotypic, genotypic and phylogenetic results demonstrate that strain AJ261T represents a novel species within the genus Halomonas, for which the name Halomonas caseinilytica is proposed. The type strain is AJ261T (=CGMCC 1.6773T =JCM 14802T). PMID:18450724

Wu, Yue-Hong; Xu, Xue-Wei; Huo, Ying-Yi; Zhou, Peng; Zhu, Xu-Fen; Zhang, Hui-Bin; Wu, Min

2008-05-01

248

Taxonomic study of the genera Halogeometricum and Halosarcina: transfer of Halosarcina limi and Halosarcina pallida to the genus Halogeometricum as Halogeometricum limi comb. nov. and Halogeometricum pallidum comb. nov., respectively  

PubMed Central

Members of the haloarchaeal genera Halosarcina and Halogeometricum (family Halobacteriaceae) are closely related to each other and show 96.698?% 16S rRNA gene sequence similarity. This is higher than the accepted threshold value (95?%) to separate two genera, and a taxonomic study using a polyphasic approach of all four members of the two genera was conducted to clarify their relationships. Polar lipid profiles indicated that Halogeometricum rufum RO1-4T, Halosarcina pallida BZ256T and Halosarcina limi RO1-6T are related more to each other than to Halogeometricum borinquense CGMCC 1.6168T. Phylogenetic analyses using the sequences of three different genes (16S rRNA gene, rpoB? and EF-2) strongly supported the monophyly of these four species, showing that they formed a distinct clade, separate from the related genera Halopelagius, Halobellus, Haloquadratum, Haloferax and Halogranum. The results indicate that the four species should be assigned to the same genus, and it is proposed that Halosarcina pallida and Halosarcina limi be transferred to the genus Halogeometricum as Halogeometricum pallidum comb. nov. (type strain, BZ256T?=?KCTC 4017T?=?JCM 14848T) and Halogeometricum limi comb. nov. (type strain, RO1-6T?=?CGMCC 1.8711T?=?JCM 16054T). PMID:24097833

Qiu, Xing-Xing; Zhao, Mei-Lin; Han, Dong; Zhang, Wen-Jiao; Dyall-Smith, Mike L.

2013-01-01

249

Transcriptional Characteristics Associated with Lichenysin Biosynthesis in Bacillus licheniformis from Chinese Maotai-Flavor Liquor Making.  

PubMed

This work investigated the biosynthetic mechanism of lichenysin, the newly identified nonvolatile matrix component in Chinese liquors. Transcriptomes were analyzed in three producers, Bacillus licheniformis CGMCC 3961, 3962, and 3963, which were isolated from Maotai-flavor liquor-making process and produced 386.3, 553.5, and 795.2 ?g/L lichenysin in a simulative liquor fermentation process. Lichenysin synthetase genes lchAA-AD in these three producers were expressed much more highly than those of the nonproducer B. licheniformis ATCC 14580 (>18.4-fold). In addition, ABC transporters were the most significant responsive metabolic pathway, and the expression levels of peptide transporter genes dppABCDE all increased more than 19.2-fold. When B. licheniformis CGMCC 3963 was cultured in synthetic medium, the expression of dppABCDE and lichenysin both increased with the addition of casein hydrolysate (containing various peptides). This indicated that peptide would act as a substrate for lichenysin synthesis. This work sheds new light on the mechanism for lichenysin biosynthesis. PMID:25561250

Wu, Qun; Zhang, Rong; Peng, Suqin; Xu, Yan

2015-01-28

250

Pseudomonas guangdongensis sp. nov., isolated from an electroactive biofilm, and emended description of the genus Pseudomonas Migula 1894.  

PubMed

A Gram-negative, straight to slightly curved rod-shaped bacterium, motile with peritrichous flagella, designated SgZ-6(T), was isolated from an electroactive biofilm and was characterized by means of a polyphasic approach. Growth occurred with 0-5.0?% (w/v) NaCl (optimum 1?%), at pH 6.0-10.0 (optimum pH 7.0) and at 10-42 C (optimum 30 C) in trypticase soya broth. Phylogenetic analyses based on the 16S rRNA and gyrB genes identified the isolate as a member of a novel species of the genus Pseudomonas. Strain SgZ-6(T) exhibited the highest 16S rRNA gene sequence similarity to 'Pseudomonas linyingensis' CGMCC 1.10701 (97.5?%), followed by Pseudomonas sagittaria JCM 18195(T) (97.4?%), P. oleovorans subsp. lubricantis DSM 21016(T) (96.6?%), P. tuomuerensis JCM 14085(T) (96.5?%) and P. alcaliphila JCM 10630(T) (96.4?%). Strain SgZ-6(T) showed the highest gyrB gene sequence similarity of 93.7?% to 'P. linyingensis' CGMCC 1.10701 among all type strains of genus Pseudomonas. DNA-DNA pairing studies showed that strain SgZ-6(T) displayed 47.1 and 40.3?% relatedness to 'P. linyingensis' CGMCC 1.10701 and P. sagittaria JCM 18195(T), respectively. The major isoprenoid quinone was ubiquinone 9 (Q-9). The whole-cell fatty acids consisted mainly of summed feature 3 (C16?:?1?6c and/or C16?:?1?7c), C16?:?0 and summed feature 8 (C18?:?1?6c and/or C18?:?1?7c). The DNA G+C content of the genomic DNA was 68.1 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain SgZ-6(T) is proposed to represent a novel species of the genus Pseudomonas, for which the name Pseudomonas guangdongensis sp. nov. is proposed. The type strain is SgZ-6(T) (?=?CCTCC AB 2012022(T)?=?KACC 16606(T)). An emended description of the genus Pseudomonas is also proposed. PMID:23918787

Yang, Guiqin; Han, Luchao; Wen, Junlin; Zhou, Shungui

2013-12-01

251

Characterization of copper-resistant bacteria and bacterial communities from copper-polluted agricultural soils of central Chile  

PubMed Central

Background Copper mining has led to Cu pollution in agricultural soils. In this report, the effects of Cu pollution on bacterial communities of agricultural soils from Valparaiso region, central Chile, were studied. Denaturing gradient gel electrophoresis (DGGE) of the 16S rRNA genes was used for the characterization of bacterial communities from Cu-polluted and non-polluted soils. Cu-resistant bacterial strains were isolated from Cu-polluted soils and characterized. Results DGGE showed a similar high number of bands and banding pattern of the bacterial communities from Cu-polluted and non-polluted soils. The presence of copA genes encoding the multi-copper oxidase that confers Cu-resistance in bacteria was detected by PCR in metagenomic DNA from the three Cu-polluted soils, but not in the non-polluted soil. The number of Cu-tolerant heterotrophic cultivable bacteria was significantly higher in Cu-polluted soils than in the non-polluted soil. Ninety two Cu-resistant bacterial strains were isolated from three Cu-polluted agricultural soils. Five isolated strains showed high resistance to copper (MIC ranged from 3.1 to 4.7 mM) and also resistance to other heavy metals. 16S rRNA gene sequence analyses indicate that these isolates belong to the genera Sphingomonas, Stenotrophomonas and Arthrobacter. The Sphingomonas sp. strains O12, A32 and A55 and Stenotrophomonas sp. C21 possess plasmids containing the Cu-resistance copA genes. Arthrobacter sp. O4 possesses the copA gene, but plasmids were not detected in this strain. The amino acid sequences of CopA from Sphingomonas isolates (O12, A32 and A55), Stenotrophomonas strain (C21) and Arthrobacter strain (O4) are closely related to CopA from Sphingomonas, Stenotrophomonas and Arthrobacter strains, respectively. Conclusions This study suggests that bacterial communities of agricultural soils from central Chile exposed to long-term Cu-pollution have been adapted by acquiring Cu genetic determinants. Five bacterial isolates showed high copper resistance and additional resistance to other heavy metals. Detection of copA gene in plasmids of four Cu-resistant isolates indicates that mobile genetic elements are involved in the spreading of Cu genetic determinants in polluted environments. PMID:22950448

2012-01-01

252

A high-throughput screening strategy for nitrile-hydrolyzing enzymes based on ferric hydroxamate spectrophotometry.  

PubMed

Nitrile-hydrolyzing enzymes (nitrilase or nitrile hydratase/amidase) have been widely used in the pharmaceutical industry for the production of carboxylic acids and their derivatives, and it is important to build a method for screening for nitrile-hydrolyzing enzymes. In this paper, a simple, rapid, and high-throughput screening method based on the ferric hydroxamate spectrophotometry has been proposed. To validate the accuracy of this screening strategy, the nitrilases from Rhodococcus erythropolis CGMCC 1.2362 and Alcaligenes sp. ECU0401 were used for evaluating the method. As a result, the accuracy for assaying aliphatic and aromatic carboxylic acids was as high as the HPLC-based method. Therefore, the method may be potentially used in the selection of microorganisms or engineered proteins with nitrile-hydrolyzing enzymes. PMID:21038095

He, Yu-Cai; Ma, Cui-Luan; Xu, Jian-He; Zhou, Li

2011-02-01

253

Streptomyces atacamensis sp. nov., isolated from an extreme hyper-arid soil of the Atacama Desert, Chile.  

PubMed

The taxonomic position of a Streptomyces strain isolated from an extreme hyper-arid soil sample collected from the Atacama Desert was determined using a polyphasic approach. The strain, isolate C60(T), had chemical and morphological features typical of members of the genus Streptomyces and formed a distinct phyletic line in the Streptomyces 16S rRNA gene tree, together with the type strain of Streptomyces radiopugnans. The two strains were distinguished readily using a combination of phenotypic properties and by a DNA-DNA relatedness value of 23.17 ( 0.95)%. On the basis of these genotypic and phenotypic data, it is proposed that isolate C60(T) (=CGMCC 4.7018(T)=KACC 15492(T)) be classified in the genus Streptomyces as Streptomyces atacamensis sp. nov. PMID:22199226

Santhanam, Rakesh; Okoro, Chinyere K; Rong, Xiaoying; Huang, Ying; Bull, Alan T; Weon, Hang-Yeon; Andrews, Barbara A; Asenjo, Juan A; Goodfellow, Michael

2012-11-01

254

Evaluation of the formation of volatiles and sensory characteristics of persimmon (Diospyros kaki L.f.) fruit wines using different commercial yeast strains of Saccharomyces cerevisiae.  

PubMed

This study evaluated the effects of five strains (IFFI 1346, IFFI 1363, CICC 31482, D254 and CGMCC2.346) of the yeast Saccharomyces cerevisiae on the aromatic profiles of fermented persimmon (Diospyros kaki L.f.) musts. A total of 50 and 60 compounds were identified in persimmon wine by stir bar sorptive extraction coupled with gas chromatography-mass spectrometry. According to odour activity values (OAVs), 26 detected compounds showed an OAV above 1. Principal component analysis explained the distribution of these persimmon wines on the basis of volatile compounds with OAV>1. The volatile compounds with high OAV included ethyl hexanoate, ethyl octanoate, methyl decanoate, linalool and geraniol. Quantitative descriptive analysis was employed. The result showed that persimmon wines fermented with strains IFFI 1363 and D254 were strongly correlated with persimmon, aroma harmony, fruity, fusel and taste balanced, fullness, hedonic scale. Therefore, the two yeast strains could be used as starter culture for persimmon wine production. PMID:25186058

Zhu, Jian Cai; Niu, Yun Wei; Feng, Tao; Liu, Sheng Jiang; Cheng, He Xing; Xu, Na; Yu, Hai Yan; Xiao, Zuo Bing

2014-01-01

255

Brachybacterium zhongshanense sp. nov., a cellulose-decomposing bacterium from sediment along the Qijiang River, Zhongshan City, China.  

PubMed

A cellulose-decomposing bacterium, strain JBT, was isolated from sediments along the Qijiang River, Zhongshan City, China. Results of morphological, biochemical and chemotaxonomic characterization and 16S rRNA gene sequence analysis revealed that strain JBT belonged to the genus Brachybacterium. Insertion sequence-PCR fingerprinting patterns, DNA base ratio analysis and DNA-DNA hybridization data showed that strain JBT differed from recognized species of the genus Brachybacterium. Based on polyphasic analysis, strain JBT represents a novel species of the genus Brachybacterium, for which the name Brachybacterium zhongshanense sp. nov. is proposed. The type strain is JBT (=LMG 23926T=CGMCC 1.6508T=DSM 18832T). PMID:17978212

Zhang, Guoxia; Zeng, Guoqu; Cai, Xiaowei; Deng, Suier; Luo, Huidong; Sun, Guoping

2007-11-01

256

Resistance of Bacillus subtilis spores to 12C ion beams, stimulation of high-energy charged particles in space  

NASA Astrophysics Data System (ADS)

To monitor the response of live microbes in space radiation environment with high-energy charged particles, we carry out ground stimulation radiation experiments. Spores of Bacillus (CGMCC 1.1849) species are one of the model systems used for astro- and radiobiological studies. (12) C ion beams served as stimulated space radiation from 5gry, 10gry, 20gry, 40gry, to 80gry at a rate of 15gry/min Death rates are measured and mutant strains are isolated. Five representative strains are analyzed for their corresponding gene sequences, protein sequences and gene expression index of DNA repair system gene recA and recO. The statistic results showed the strains resistance to (12) C ion beams radiation is partially due to the increase of gene expression index of recA and recO. In conclusion, our research provide a surrogate system to monitor the live microbial response in resistant to space radiation environment.

Zhang, Li; Dang, Bingrong; Li, Junxiong; Chen, Jinsong; Liu, Mei; Liu, Zhiheng; Zhang, Lixin

257

Production of nano bacterial cellulose from waste water of candied jujube-processing industry using Acetobacter xylinum.  

PubMed

The work is aimed to investigate the suitability of waste water of candied jujube-processing industry for the production of bacterial cellulose (BC) by Gluconacetobacter xylinum CGMCC No.2955 and to study the structure properties of bacterial cellulose membranes. After acid pretreatment, the glucose of hydrolysate was higher than that of waste water of candied jujube. The volumetric yield of bacterial cellulose in hydrolysate was 2.25 g/L, which was 1.5-folds of that in waste water of candied jujube. The structures indicated that the fiber size distribution was 3-14 nm in those media with an average diameter being around 5.9 nm. The crystallinity index of BC from pretreatment medium was lower than that of without pretreatment medium and BCs from various media had similar chemical binding. Ammonium citrate was a key factor for improving production yield and the crystallinity index of BC. PMID:25662694

Li, Zheng; Wang, Lifen; Hua, Jiachuan; Jia, Shiru; Zhang, Jianfei; Liu, Hao

2015-04-20

258

Haloarcula amylolytica sp. nov., an extremely halophilic archaeon isolated from Aibi salt lake in Xin-Jiang, China.  

PubMed

A starch-hydrolysing and extremely halophilic archaeon (strain BD-3(T)), isolated from Aibi salt lake in Xin-Jiang, China, was characterized phenotypically and genotypically in order to determine its taxonomic status. On the basis of its polar lipid composition, nucleotide sequences of its 16S rRNA genes, genomic DNA G+C content (62.4 mol%) and growth characteristics, the organism could be assigned to the genus Haloarcula. Phenotypic differences and low DNA-DNA hybridization values to related Haloarcula species distinguished strain BD-3(T) from recognized Haloarcula species. It is therefore concluded that strain BD-3(T) represents a novel species, for which the name Haloarcula amylolytica sp. nov. is proposed. The type strain is BD-3(T) (=CGMCC 1.5335(T)=JCM 13557(T)). PMID:17220450

Yang, Yong; Cui, Heng-Lin; Zhou, Pei-Jin; Liu, Shuang-Jiang

2007-01-01

259

Therapeutic effects of Clostridium butyricum on experimental colitis induced by oxazolone in rats  

PubMed Central

AIM: To evaluate the therapeutic effects of a probiotic supplement (Clostridium butyricum, CGMCC0313) in a chemically-induced rat model of experimental colitis. METHODS: An experimental ulcerative colitis model was established by rectal injection of oxazolone into the colon of 40 Wistar rats randomly divided into four groups. The positive control group was sacrificed 3 d after colitis onset. The remaining groups were fed daily with either 2 mL of C. butyricum (2.3 1011 CFU/L), 2 mL of mesalamine (100 g/L), or 1 mL of sodium butyrate (50 mmol/L) for 21 d. The animals body weight, behavior, and bowel movements were recorded weekly. After sacrifice, visual and microscopic observations of pathological changes of colon tissue were made, body weight and wet colon mass index were measured and recorded, and serum levels of interleukin-23 (IL-23) and TNF-? were measured using ELISA. Expression of calcitonin gene-related peptide in colon tissue was measured by RT-PCR. Finally, changes in rat intestinal microflora status were measured in all groups. RESULTS: We found that treatment with C. butyricum lowered the serum levels of both IL-23 and tumor necrosis factor-? (TNF-?) with similar or even better efficiency than that of mesalamine or sodium butyrate. The rat intestinal flora appeared to recover more quickly in the group treated with C. butyricum than in the mesalamine and sodium butyrate groups. Finally, we found that the expression level of calcitonin gene related peptide was elevated in colon tissue in the sodium butyrate treated group but not in the C. butyricum or mesalamine treated groups, indicating a sensitization of colon following sodium butyrate treatment. CONCLUSION: In our experimental colitis model, treatment with C. butyricum CGMCC0313, a probiotic supplement, is at least as efficient as treatment with mesalamine. PMID:19370778

Zhang, Hai-Qiang; Ding, Tomas T; Zhao, Jun-Sheng; Yang, Xin; Zhang, Hai-Xia; Zhang, Juan-Juan; Cui, Yun-Long

2009-01-01

260

Pseudomonas oryzae sp. nov. isolated from a paddy soil in South China.  

PubMed

A Gram-staining-negative, rod-shaped and motile with several polar flagellums bacterium, designated WM-3(T), was isolated from a rice paddy soil in South China. Growth occurred with 0-3.0% (w/v) NaCl (optimum 2.0%), at pH 5.5-9.0 (optimum pH 7.0) and at 25-42C (optimum 30-37C) in liquid Reasoner's 2A medium. Analysis of the 16S rRNA gene and gyrB gene sequences revealed that strain WM-3(T) was most closely related to the type strains of the species Pseudomonas linyingensis and Pseudomonas sagittaria. Its sequence similarities with P. linyingensis CGMCC 1.10701(T) and P. sagittaria JCM 18195(T) were 97.4 and 97.3%, respectively, for 16S rRNA gene, and were 94.1 and 94.2%, respectively, for gyrB gene. DNA-DNA hybridization between strain WM-3(T) and these two type strains showed relatedness of 35.6 and 30.9%, respectively. G+C content of genomic DNA was 69.4mol%. The whole-cell fatty acids mainly consisted of C16:0 (30.0%), C16:1 ?6c and/or C16:1 ?7c (19.3%) and C18:1 ?6c and/or C18:1 ?7c (16.3%). The results of phenotypic, chemotaxonomic and genotypic analyses clearly indicated that strain WM-3(T) belongs to genus Pseudomonas but represents a novel species, for which the name Pseudomonas oryzae sp. nov. is proposed. The type strain is WM-3(T) (=KCTC 32247(T) =CGMCC 1.12417(T)). PMID:24142159

Yu, Zhen; Chang, Ming; Wu, Min; Yang, Guiqin; Zhou, Shungui; Zhuang, Li

2013-12-01

261

Halogranum gelatinilyticum sp. nov. and Halogranum amylolyticum sp. nov., isolated from a marine solar saltern, and emended description of the genus Halogranum.  

PubMed

Two extremely halophilic archaeal strains, designated TNN44(T) and TNN58(T), were isolated from Tainan marine solar saltern near Lianyungang city, Jiangsu province, China. Cells of the two strains were pleomorphic and Gram-stain-negative; colonies were red-pigmented. Strains TNN44(T) and TNN58(T) were able to grow at 20-50 C (optimum 37 C for both), in the presence of 1.4-5.1 M NaCl (optimum 3.4-3.9 M NaCl) and at pH 5.5-9.0 (optimum pH 6.5-7.0); neither strain required Mg(2+) for growth. Cells lysed in distilled water. On the basis of 16S rRNA gene sequence analysis, strains TNN44(T) and TNN58(T) were related closely to Halogranum rubrum RO2-11(T) (96.2 and 97.2?% similarity, respectively). The polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate (trace), and one major glycolipid and one minor glycolipid chromatographically identical to sulfated mannosyl glucosyl diether and mannosyl glucosyl diether, respectively; other trace unidentified lipids were also detected. The DNA G+C content of strains TNN44(T) and TNN58(T) was 64.0 and 62.0 mol%, respectively. The level of DNA-DNA relatedness between strains TNN44(T) and TNN58(T) was 37.2?%, and these two strains showed a low level of DNA-DNA relatedness with Halogranum rubrum RO2-11(T) (40.6 and 44.4?%, respectively). Two novel species of the genus Halogranum are proposed to accommodate these two strains, Halogranum gelatinilyticum sp. nov. (type strain TNN44(T) ?=?CGMCC 1.10119(T) ?=?JCM 16426(T)) and Halogranum amylolyticum sp. nov. (type strain TNN58(T) ?=?CGMCC 1.10121(T) ?=?JCM 16428(T)). PMID:20495026

Cui, Heng-Lin; Yang, Xin; Gao, Xia; Xu, Xue-Wei

2011-04-01

262

Salinarchaeum laminariae gen. nov., sp. nov.: a new member of the family Halobacteriaceae isolated from salted brown alga Laminaria.  

PubMed

Halophilic archaeal strains R26(T) and R22 were isolated from the brown alga Laminaria produced at Dalian, Liaoning Province, China. Cells from the two strains were pleomorphic rods and Gram negative, and colonies were red pigmented. Strains R26(T) and R22 were able to grow at 20-50C (optimum 37C) in 1.4-5.1M NaCl (optimum 3.1-4.3M) at pH 5.5-9.5 (optimum pH 8.0-8.5) and neither strain required Mg(2+) for growth. Cells lyse in distilled water and the minimum NaCl concentration required to prevent cell lysis was 8% (w/v) for strain R26(T) and 12% (w/v) for strain R22. The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and minor phosphatidylglycerol sulfate; glycolipids were not detected. Phylogenetic analyses based on 16S rRNA genes and rpoB' genes revealed that strains R26(T) and R22 formed a distinct clade with the closest relative, Natronoarchaeum mannanilyticum. The DNA G+C content of strains R26(T) and R22 was 65.8 and 66.4mol%, respectively. The DNA-DNA hybridization value between strains R26(T) and R22 was 89%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that the strains R26(T) and R22 represent a novel species in a new genus within the family Halobacteriaceae, for which the name Salinarchaeum laminariae gen. nov., sp. nov. is proposed. The type strain is R26(T) (type strain R26(T)=CGMCC 1.10590(T)=JCM 17267(T), reference strain R22=CGMCC 1.10589). PMID:21901373

Cui, Heng-Lin; Yang, Xin; Mou, Yun-Zhuang

2011-11-01

263

Halobellus inordinatus sp. nov., from a marine solar saltern and an inland salt lake of China.  

PubMed

Two halophilic archaeal strains, YC20(T) and XD15, were isolated from a marine solar saltern and an inland salt lake in China. Both had pleomorphic cells that lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. They were neutrophilic, requiring at least 100 g NaCl l(-1) and 0.5-95 g MgCl2 l(-1) for growth at the optimum growth temperature of 37 C. The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS) and two major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1), respectively. Trace amounts of two unidentified glycolipids were also detected. The 16S rRNA gene sequences of the two strains were 99.5?% identical and showed 94.0-95.9?% similarity to the most closely related members of the genus Halobellus of the family Halobacteriaceae. The rpoB' gene sequence similarity between strains YC20(T) and XD15 was 98.2?% and these sequences showed 89.6-92.8?% similarity to those of the most closely related members of the genus Halobellus. The DNA G+C contents of strains YC20(T) and XD15 were 65.8 mol% and 65.4 mol%, respectively. The DNA-DNA hybridization value between strain YC20(T) and strain XD15 was 92?%, and the two strains showed low DNA-DNA relatedness to members of the genus Halobellus. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains YC20(T) and XD15 represent a novel species of the genus Halobellus, for which the name Halobellus inordinatus sp. nov. is proposed. The type strain is YC20(T) (?=?CGMCC 1.12120(T)?=?JCM 18361(T)) and the other strain is XD15 (?=?CGMCC 1.12236?=?JCM 18648). PMID:23728369

Qiu, Xing-Xing; Mou, Yun-Zhuang; Zhao, Mei-Lin; Zhang, Wen-Jiao; Han, Dong; Ren, Min; Cui, Heng-Lin

2013-11-01

264

Halosimplex pelagicum sp. nov. and Halosimplex rubrum sp. nov., isolated from salted brown alga Laminaria, and emended description of the genus Halosimplex.  

PubMed

Two halophilic archaeal strains, R2(T) and R27(T), were isolated from the brown alga Laminaria produced at Dalian, Liaoning Province, China. Both had pleomorphic cells that lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. They grew optimally at 42 C, pH 7.0 and in the presence of 3.1-3.4 M NaCl and 0.03-0.5 M Mg(2+). The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me) and four major glycolipids chromatographically identical to those of Halosimplex carlsbadense JCM 11222(T). 16S rRNA gene analysis revealed that each strain had two dissimilar 16S rRNA genes and both strains were phylogenetically related to Halosimplex carlsbadense JCM 11222(T) (92.7-98.8?% similarities). The rpoB' gene similarities between strains R2(T) and R27(T) and between these strains and Halosimplex carlsbadense JCM 11222(T) were 95.7?%, 96.1?% and 95.8?%, respectively. The DNA G+C contents of strains R2(T) and R27(T) were 62.5 mol% and 64.0 mol%, respectively. The DNA-DNA hybridization values between strains R2(T) and R27(T) and between the two strains and Halosimplex carlsbadense JCM 11222(T) were 43?%, 52?% and 47?%, respectively. It was concluded that strain R2(T) (?=?CGMCC 1.10586(T)?=?JCM 17263(T)) and strain R27(T) (?=?CGMCC 1.10591(T)?=?JCM 17268(T)) represent two novel species of the genus Halosimplex, for which the names Halosimplex pelagicum sp. nov. and Halosimplex rubrum sp. nov. are proposed. An emended description of the genus Halosimplex is also presented. PMID:24048865

Han, Dong; Cui, Heng-Lin

2014-01-01

265

Pelagibacterium halotolerans gen. nov., sp. nov. and Pelagibacterium luteolum sp. nov., novel members of the family Hyphomicrobiaceae.  

PubMed

Two Gram-negative, motile, aerobic bacterial strains, designated B2(T) and 1_C16_27(T), were respectively isolated from a seawater sample collected from the East China Sea and a semi-coke sample from north-eastern Estonia. Their genetic, phenotypic and chemotaxonomic properties were studied. The isolates were short rods with polar flagella and were positive for catalase and oxidase activities. Q-10 was the predominant respiratory ubiquinone. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and two unidentified glycolipids. The major fatty acids were nonadecanoic (C(19 : 0) cyclo), octadecanoic (C(18 : 0) and C(18 : 0) 3-OH), octadecenoic (C(18 : 1)) and hexadecanoic (C(16 : 0)) acids. The G+C content of the genomic DNA was 58.1-59.3 mol%. 16S rRNA gene sequence analysis revealed that the two isolates represent a distinct lineage within the family Hyphomicrobiaceae. The phylogenetically closest relatives were Cucumibacter (92.7-93.7 % 16S rRNA gene sequence similarity), Devosia (92.9-94.4 %) and Zhangella (91.7-92.1 %). Differential phenotypic properties, together with phylogenetic and genetic distinctiveness, revealed that strains B2(T) and 1_C16_27(T) could be differentiated from each other and from members of the genera Cucumibacter, Devosia and Zhangella. Therefore, it is proposed that strains B2(T) and 1_C16_27(T) represent two novel species in a new genus, for which the names Pelagibacterium halotolerans gen. nov., sp. nov. (the type species; type strain B2(T) ?=?CGMCC 1.7692(T) ?=?JCM 15775(T)) and Pelagibacterium luteolum sp. nov. (type strain 1_C16_27(T) ?=?CGMCC 1.10267(T) ?= JCM 16552(T) ?= CELMS EEUT 1C1627(T)) are proposed. PMID:20817840

Xu, Xue-Wei; Huo, Ying-Yi; Wang, Chun-Sheng; Oren, Aharon; Cui, Heng-Lin; Vedler, Eve; Wu, Min

2011-08-01

266

Taxonomic evaluation of the Streptomyces hygroscopicus clade using multilocus sequence analysis and DNA-DNA hybridization, validating the MLSA scheme for systematics of the whole genus.  

PubMed

Streptomyces hygroscopicus and related species are the most well known candidate producers of antibiotics and many other industrially and agronomically important secondary metabolites in the genus Streptomyces. Multilocus sequence analysis (MLSA) has shown to be a powerful and pragmatic molecular method for unraveling streptomycete diversities. In this investigation, a multilocus phylogeny of 58 representatives of the S. hygroscopicus 16S rRNA gene clade including S. violaceusniger and related species was examined. The result demonstrated that the MLSA data were helpful in defining members of the S. hygroscopicus clade, providing further evidence that the MLSA scheme of five housekeeping genes (atpD, gyrB, recA, rpoB and trpB) is a valuable alternative for creating and maintaining operational protocols for the Streptomyces species assignment. DNA-DNA hybridization (DDH) between strains with representative MLSA evolutionary distances, combined with previous data from S. griseus and S. albidoflavus clades, revealed a high correlation between MLSA and DDH, and sustains that the five-gene nucleotide sequence distance of 0.007 could be considered as the species cut-off for the whole genus. This significant correlation thus makes the MLSA scheme applicable to construction of a theory-based taxonomy for both ecology and bioprospecting of streptomycetes. Based on the MLSA and DDH data, as well as phenotypic characteristics, 10 species and three subspecies of the S. hygroscopicus clade are considered to be later heterotypic synonyms of eight genomic species, and Streptomyces glebosus sp. nov., comb. nov. (type strain CGMCC 4.1873(T)=LMG 19950(T)=DSM 40823(T)) and Streptomyces ossamyceticus sp. nov., comb. nov. (type strain CGMCC 4.1866(T)=LMG 19951(T)=DSM 40824(T)) are also proposed. PMID:22172557

Rong, Xiaoying; Huang, Ying

2012-02-01

267

Culture-dependent and culture-independent analysis of hydrocarbonoclastic microorganisms indigenous to hypersaline environments in Kuwait.  

PubMed

The halophilic, hydrocarbonoclastic bacteria and archaea inhabiting two hypersaline coastal areas in Kuwait, one in the north and the other in the south, were counted and characterized. Environmental parameters in both areas were similar, with the exception of the soil organic carbon content, which was in the north higher than in the south. The hydrocarbonoclastic bacterial and haloarchaeal numbers and identities as analyzed using nutrient media of various salinities were similar in soil and pond water samples from both areas. The bacterial species recorded by this culture-dependent method belonged to the genera Halomonas, Chromohalobacter, Marinobacter, Exiguobacterium, Stenotrophomonas, Pseudomonas, Salinivibrio, and Bacillus. The haloarchaeal species belonged to the genera Haloferax and Halobacterium. When analyzed by fingerprinting of their amplified genomic DNA followed by sequencing of the electrophoresis-resolved bands, the same environmental samples revealed a different microbial composition. Bacterial phylotypes recorded by this culture-independent method were affiliated with the genera Ochrobactrum, Stenotrophomonas, Rhodococcus, and "Halomicrobium," whereas the archaeal phylotypes were affiliated with Halorussus, Halomicrobium, and Halorientalis. The observed diversity and composition similarity of the hydrocarbonocalastic microflora in both hypersaline areas suggest an effective potential for oil mineralization therein. This potential has been confirmed experimentally. PMID:24682340

Al-Mailem, Dina; Eliyas, Mohamed; Khanafer, Majeda; Radwan, Samir

2014-05-01

268

Isolation and Characterization of Lipase-Producing Bacteria in the Intestine of the Silkworm, Bombyx mori, Reared on Different Forage  

PubMed Central

The silkworm, Bombyx mori L. (Lepidoptera: Bombycidae), an oligophagous insect that mainly feeds on mulberry leaves, is susceptible to entomopathogen infection when reared with tricuspid cudrania leaves. A total of 56 dominant bacterial strains, classified into 12 phylotypes based on bacteriological properties and analysis of 16S rRNA genes, were isolated from the intestine of the fourth and fifth instar silkworm larvae. Ten and seven phylotypes exist in the intestine of the silkworm larvae reared with mulberry leaves and tricuspid cudrania leaves, respectively. Four of them are common in the intestine of the two treatment groups. By screening their lipolytic ability on a Rhodamine B agar plate, nine lipase-producing bacterial strains were obtained and classified into six genera, including Bacillus, Brevibacterium, Corynebacterium, Staphylococcus, Klebsiella, and Stenotrophomonas. Except for Stenotrophomonas, which is common in both, the other genera only exist in the intestine of the silkworm larvae fed with mulberry leaves. In addition, by culture and fermentation in vitro, the maximum cell density and lipase activity of lipase-producing bacteria were examined at about 48 hours. The results indicate that diet has a significant impact on the gut bacterial community, especially lipase-producing bacteria. We suggest that the difference of lipase-producing bacterial diversity might be related to disease resistance of the silkworm. PMID:22243438

Feng, Wei; Wang, Xiao-Qiang; Zhou, Wei; Liu, Guang-Ying

2011-01-01

269

Distinct diversity of the czcA gene in two sedimentary horizons from a contaminated estuarine core.  

PubMed

In estuarine ecosystems, trace metals are mainly associated with fine grain sediments which settle on mudflats. Over time, the layers of sediments accumulate and are then transformed by diagenetic processes, recording the history of the estuary's chemical contamination. In such a specific environment, we investigated to what extent a chronic exposure to contaminants could affect metal-resistant sedimentary bacteria in subsurface sediments. The occurrence and diversity of cadmium resistance genes (cadA, czcA) was investigated in 5- and 33-year-old sediments from a highly contaminated estuary (Seine France). Primers were designed to detect a 252-bp fragment of the czcA gene, specifically targeting a transmembrane helice domain (TMH IV) involved in the proton substrate antiport of this efflux pump. Although the cadA gene was not detected, the highest diversity of the sequence of the czcA gene was observed in the 5-year-old sediment. According to the percentage of identity at the amino acid level, the closest CzcA relatives were identified among Proteobacteria (?, ?, ?, and ?), Verrucomicrobia, Nitrospirae, and Bacteroidetes. The most abundant sequences were affiliated with Stenotrophomonas. In contrast, in the 33-year-old sediment, CzcA sequences were mainly related to Rhodanobacter thiooxydans and Stenotrophomonas, suggesting a shaping of the metal-resistant microbial communities over time by both diagenetic processes and trace metal contamination. PMID:24894751

Kaci, Assia; Petit, Fabienne; Lesueur, Patrick; Boust, Dominique; Vrel, Anne; Berthe, Thierry

2014-09-01

270

Restricted streptomycin use in apple orchards did not adversely alter the soil bacteria communities  

PubMed Central

Streptomycin has been authorized for restricted use in the prevention of the fire blight disease of pome fruit orchards in the EU and Switzerland. This study addresses the important topic of the influence of the use of streptomycin in agriculture on the total bacteria community within the soil ecosystem. Soil samples were taken from soils under apple trees, prior to streptomycin application and 2 weeks post streptomycin application or water application (untreated control). High throughput 16S rRNA gene amplicon sequencing was used to generate datasets from the soils under apple trees in apple orchards from three different locations in Switzerland. We hypothesized that the use of streptomycin would reduce the bacterial diversity within the soil samples and enhance a reduction in the variety of taxa present. Bacterial species such as Pseudomonas, Burkholderia, and Stenotrophomonas are intrinsically resistant to many antibiotics and as such it is of interest to investigate if the use of streptomycin provided a selective advantage for these bacteria in the soil ecosystem. The application of streptomycin did not influence the abundance and diversities of major bacteria taxa of the soils or the Pseudomonas, Burkholderia, and Stenotrophomonas species. We also discovered that apple orchards under the same management practices, did not harbor the same bacterial communities. The restricted application of streptomycin in the protection of apple orchards from the fire blight pathogen Erwinia amylovora under the guidelines in Switzerland did not alter either the bacterial diversity or abundance within these soil ecosystems. PMID:24550889

Walsh, Fiona; Smith, Daniel P.; Owens, Sarah M.; Duffy, Brion; Frey, Jrg E.

2014-01-01

271

Restricted streptomycin use in apple orchards did not adversely alter the soil bacteria communities.  

PubMed

Streptomycin has been authorized for restricted use in the prevention of the fire blight disease of pome fruit orchards in the EU and Switzerland. This study addresses the important topic of the influence of the use of streptomycin in agriculture on the total bacteria community within the soil ecosystem. Soil samples were taken from soils under apple trees, prior to streptomycin application and 2 weeks post streptomycin application or water application (untreated control). High throughput 16S rRNA gene amplicon sequencing was used to generate datasets from the soils under apple trees in apple orchards from three different locations in Switzerland. We hypothesized that the use of streptomycin would reduce the bacterial diversity within the soil samples and enhance a reduction in the variety of taxa present. Bacterial species such as Pseudomonas, Burkholderia, and Stenotrophomonas are intrinsically resistant to many antibiotics and as such it is of interest to investigate if the use of streptomycin provided a selective advantage for these bacteria in the soil ecosystem. The application of streptomycin did not influence the abundance and diversities of major bacteria taxa of the soils or the Pseudomonas, Burkholderia, and Stenotrophomonas species. We also discovered that apple orchards under the same management practices, did not harbor the same bacterial communities. The restricted application of streptomycin in the protection of apple orchards from the fire blight pathogen Erwinia amylovora under the guidelines in Switzerland did not alter either the bacterial diversity or abundance within these soil ecosystems. PMID:24550889

Walsh, Fiona; Smith, Daniel P; Owens, Sarah M; Duffy, Brion; Frey, Jrg E

2013-01-01

272

Bacterial Symbionts in the Sugar Beet Root Maggot, Tetanops myopaeformis (von Rder)  

PubMed Central

Aerobic heterotrophic and facultative anaerobic bacteria were isolated from all developmental stages of the sugar beet root maggot, Tetanops myopaeformis (von Rder). Two distinct bacterial symbiotic relationships were observed. Serratia liquefaciens and Serratia marcescens were found to be associated with all developmental stages. Bacterial symbiont transmission occurred from one generation to the next. Symbionts were transferred from the male reproductive system to the female reproductive system, where both an internal infiltration of the egg chorion and an external smearing of the eggs occurred during oviposition. Pseudomonas maltophilia was found in association with the larval gut and the inner surface of the puparium. Electron microscopy of the inner puparial surface revealed symbionts within the chitinous wall. In vitro symbiont chitinase production was found, using both nephelometric (turbidimetric) and N-acetylglucosamine assays. A relationship appeared to exist between adult fly emergence and enzymatic chitin degradation of the puparium by the bacterial symbionts. Images PMID:16346457

Iverson, Kathy L.; Bromel, Mary C.; Anderson, Albin W.; Freeman, Thomas P.

1984-01-01

273

Meteorite organics in planetary environments: hydrothermal release, surface activity, and microbial utilization  

NASA Technical Reports Server (NTRS)

Up to 50% of the organics in the Murchison meteorite, possibly including some of the polymer, is released in high temperature and pressure aqueous environments, to 350 degrees C and 250 bar, that simulate submarine volcanic, hydrothermal or impact-induced conditions. Meteorite organics of prebiotic significance, such as nonanoic acid, glycine, and pyrene survive the hydrothermal conditions. The released material is surface active with surface pressures up to 19.8 x 10(-3) N m-1, and exhibits an extended surface tension isotherm which suggests a mixture of amphiphilic components. One component, nonanoic acid, is shown to form vesicles. The materials extracted under mild conditions, at 120 degrees C, are nutrients for the humic acid bacterium Pseudomonas maltophilia and efficient nutrients for the oligotroph Flavobacterium oryzihabitans, demonstrating the capability of microorganisms to metabolize extraterrestrial organics.

Mautner, M. N.; Leonard, R. L.; Deamer, D. W.

1995-01-01

274

Analysis of the interaction between autochthonous bacteria and packaging material in PVC-bottled mineral water.  

PubMed

A study with about 10,000 bottles produced by a mineral water company was undertaken in order to identify the causal agent of an off-odour occurrence in the bottled water. Some physiological attributes of the dominant species over an 8-month period, as well as their interaction with packaging material, were investigated. Pseudomonas maltophilia, P. acidovorans, Acinetobacter calcoaceticus var. lowffi, frequently associated with bottles having an off-odour, seemed to play a decisive role in the phenomenon due to their elevated lipolytic activity, their cell hydrophobicity and adhesivity to the PVC walls. Their ability to attack the sodium polysulfide included in the ultramarine blue dye present in PVC, transforming it to H2S was investigated. PMID:7921893

Guerzoni, M E; Lanciotti, R; Sinigaglia, M; Gardini, F

1994-06-01

275

Halomonas songnenensis sp. nov., a moderately halophilic bacterium isolated from saline and alkaline soils.  

PubMed

A moderately halophilic bacterium (strain NEAU-ST10-39T) was isolated from saline and alkaline soils in the oilfield of Daqing City, Heilongjiang Province, China. The strain was strictly aerobic, Gram-stain-negative, rod-shaped and motile by peritrichous flagella. Its colonies were yellow. It grew at NaCl concentrations of 0.2-15% (w/v) (optimum 4%, w/v), at temperatures of 4-40 C (optimum 35 C) and at pH 5-10 (optimum pH 7). It did not produce acids from sugars or alcohols. Its DNA G+C content was 57.4 mol%. Phylogenetic analyses based on 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD gene sequences indicated that it belonged to the genus Halomonas in the class Gammaproteobacteria. The most phylogenetically related species were Halomonas axialensis, Halomonas meridiana and Halomonas aquamarina, whose types shared 98.3% (16S rRNA), 82.7% (gyrB) and 83.9-84.5% (rpoD) sequence similarity with strain NEAU-ST10-39T. The results of DNA-DNA hybridization assays showed 202%-501?% relatedness between strain NEAU-ST10-39T and the most closely related species including Halomonas axialensis DSM 15723T, Halomonas meridiana DSM 5425T, Halomonas aquamarina DSM 30161(T), Halomonas johnsoniae DSM 21197T, Halomonas stevensii DSM 21198T, Halomonas nanhaiensis CCTCC AB 2012911(T), Halomonas hamiltonii DSM 21196T and Halomonas arcis CGMCC 1.6494T. The major fatty acids were C18?:?1?7c (47.2%), C16:1?7c and/or C16:1?6c (18.9%) and C16:0 (16.3%), the only respiratory quinone detected was ubiquinone 9 and polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unknown phospholipids and three unknown lipids. The new isolate is proposed to represent a novel species with the name Halomonas songnenensis sp. nov., NEAU-ST10-39T (=CGMCC 1.12152T=DSM 25870T) being the type strain. PMID:24510978

Jiang, Juquan; Pan, Yuanyuan; Hu, Shaoxin; Zhang, Xiaoxia; Hu, Baozhong; Huang, Haipeng; Hong, Shan; Meng, Jing; Li, Cheng; Wang, Kaibiao

2014-05-01

276

Reclassification of Bacillus beijingensis Qiu et al. 2009 and Bacillus ginsengi Qiu et al. 2009 as Bhargavaea beijingensis comb. nov. and Bhargavaea ginsengi comb. nov. and emended description of the genus Bhargavaea.  

PubMed

We have carried out a polyphasic taxonomic characterization of Bacillus beijingensis DSM 19037(T) and Bacillus ginsengi DSM 19038(T), which are closely related phylogenetically to Bhargavaea cecembensis LMG 24411(T). All three strains are Gram-stain-positive, non-motile, moderately halotolerant and non-spore-forming. 16S rRNA gene sequence analyses showed that the strains constituted a coherent cluster, with sequence similarities between 99.7 and 98.7?%. The percentage similarity on the basis of amino acid sequences deduced from partial gyrB gene nucleotide sequences of these three type strains was 96.1-92.7?%. Phylogenetic trees based on the 16S rRNA gene and GyrB amino acid sequences, obtained by using three different algorithms, were consistent and showed that these three species constituted a deeply rooted cluster separated from the clades represented by the genera Bacillus, Planococcus, Planomicrobium, Sporosarcina, Lysinibacillus, Viridibacillus, Kurthia and Geobacillus, supporting their placement in the genus Bhargavaea. All three type strains have menaquinone MK-8 as the major respiratory quinone and showed similar fatty acid profiles. The main polar lipids present in the three type strains were diphosphatidylglycerol and phosphatidylglycerol, and the three strains showed peptidoglycan type A4? with L-lysine as the diagnostic diamino acid. The DNA G+C contents of Bacillus beijingensis DSM 19037(T), Bacillus ginsengi DSM 19038(T) and Bhargavaea cecembensis LMG 24411(T) were 53.1, 50.2 and 53.7 mol%, respectively. The level of DNA-DNA hybridization among the three strains was 57-39?%, indicating that they are members of different species of the genus Bhargavaea. The phenotypic data are consistent with the placement of these three species in a single genus and support their differentiation at the species level. On the basis of these data, we have emended the description of the genus Bhargavaea and propose the reclassification of Bacillus beijingensis and Bacillus ginsengi to the genus Bhargavaea, as Bhargavaea beijingensis comb. nov. (type strain ge10(T) ?=?DSM 19037(T) ?=?CGMCC 1.6762(T)) and Bhargavaea ginsengi comb. nov. (type strain ge14(T) ?=?DSM 19038(T) ?=?CGMCC 1.6763(T)). PMID:22155760

Verma, Pankaj; Pandey, Prashant Kumar; Gupta, Arvind Kumar; Seong, Chi Nam; Park, Seong Chan; Choe, Han Na; Baik, Keun Sik; Patole, Milind Shivaji; Shouche, Yogesh Shreepad

2012-10-01

277

Flavobacterium aquaticum sp. nov., isolated from a water sample of a rice field.  

PubMed

Strain JC164(T) was isolated from a water sample from a rice field at Jamdih, Mau, Uttar Pradesh, India. Colonies of strain JC164(T) were brown-yellow and cells were Gram-stain-negative. Catalase, oxidase and amylase were present. iso-C(15:0), iso-C(16:0), iso-C15?1 G, iso-C(15:0) 3-OH and iso-C(14:0) were the predominant fatty acids with minor amounts of iso-C(16:0) 3-OH, anteiso-C(15:0), C(16:0), iso-C(16:1) H, iso-C(14:0) 3-OH and iso-C(13:0). Strain JC164(T) contained phosphatidylethanolamine and a few unidentified lipids (L1, L3 and L6) as major polar lipids. Bacteriohopane derivative 1 (BHD1) and diplopterol (DPL) were the major hopanoids. ?-Carotene was one among the several spirilloxanthin series carotenoids present in strain JC164(T). Genomic DNA G+C content was 39.6 mol%. 16S rRNA gene sequence comparisons indicated that strain JC164(T) represents a member of the genus Flavobacterium (family Flavobacteriaceae, class Flavobacteriia). The most closely related taxa to strain JC164(T) were Flavobacterium sasangense YC6274(T) (98.5%), Flavobacterium cucumis R2A45-3(T) (98.1%), Flavobacterium cheniae NJ-26(T) (97.2%) and the novel strain possessed <95.1% sequence similarity with other members of the genus Flavobacterium. However, strain JC164(T) showed 12.5 2, 13.6 1 and 17.4 2% genomic DNA association (based on DNA-DNA hybridization) with Flavobacterium sasangense KCTC 22246(T), Flavobacterium cucumis DSM 18830(T) and Flavobacterium cheniae CGMCC 1.6844(T), respectively. The distinct genomic difference and morphological, physiological and chemotaxonomic differences from the previously described taxa support the classification of strain JC164(T) as a representative of a novel species of the genus Flavobacterium, for which the name Flavobacterium aquaticum sp. nov. is proposed. The type strain is JC164(T) (?=?KCTC 32196(T)?=?CGMCC 1.12398=LMG 27251(T)). PMID:23543500

Subhash, Y; Sasikala, Ch; Ramana, Ch V

2013-09-01

278

Halorubellus salinus gen. nov., sp. nov. and Halorubellus litoreus sp. nov., novel halophilic archaea isolated from a marine solar saltern.  

PubMed

Two extremely halophilic archaeal strains GX3(T) and GX26(T) were isolated from the Gangxi marine solar saltern near the Weihai city of Shandong Province, China. Cells from the two strains were pleomorphic and stained Gram-negative, colonies were red-pigmented. Strains GX3(T) and GX26(T) were able to grow at 25-50 C (optimum 37 C), at 1.4-5.1M NaCl (optimum 3.1M), at pH 5.5-9.5 (optimum pH 7.0) and neither strain required Mg(2+) for growth. Cells lyse in distilled water and the minimal NaCl concentration to prevent cell-lysis was 8% (w/v). The major polar lipids of the two strains were PA (phosphatidic acid), PG (phosphatidylglycerol), PGP-Me (phosphatidylglycerol phosphate methyl ester) and three major glycolipids (GL1, GL2 & GL3) chromatographically identical to S-TGD-1 (sulfated galactosyl mannosy glucosyl diether), S-DGD-1 (sulfated mannosyl glucosyl diether), and DGD-1 (mannosyl glucosyl diether) respectively, an unidentified lipid (GL4) was also detected in strain GX26(T). Phylogenetic analysis based on 16S rRNA gene revealed that strain GX3(T) and strain GX26(T) formed a distinct clade with the closest relative, Haladaptatus paucihalophilus (89.9-92.4% and 90.4-92.7, respectively). The rpoB' gene similarities between strains GX3(T) and GX26(T), and between the two strains and the closest relative, Halorussus rarus TBN4(T) are 96.5%, 84.3% and 83.9%, respectively. The DNA G+C contents of strain GX3(T) and strain GX26(T) are 67.3 mol% and 67.2 mol%, respectively. The DNA-DNA hybridization value between strain GX3(T) and strain GX26(T) was 44%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain GX3(T) and strain GX26(T) represent two novel species in a new genus within the family Halobacteriaceae, Halorubellus salinus gen. nov., sp. nov. (type strain GX3(T)=CGMCC 1.10384(T)=JCM 17115(T)) and Halorubellus litoreus sp. nov. (type strain GX26(T)=CGMCC 1.10386(T)=JCM 17117(T)). PMID:21889861

Cui, Heng-Lin; Mou, Yun-Zhuang; Yang, Xin; Zhou, Yu-Guang; Liu, Hong-Can; Zhou, Pei-Jin

2012-02-01

279

Bacillus beijingensis sp. nov. and Bacillus ginsengi sp. nov., isolated from ginseng root.  

PubMed

Four alkaligenous, moderately halotolerant strains, designated ge09, ge10(T), ge14(T) and ge15, were isolated from the internal tissue of ginseng root and their taxonomic positions were investigated by using a polyphasic approach. Cells of the four strains were Gram-positive-staining, non-motile, short rods. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains ge09 and ge10(T) formed one cluster and strains ge14(T) and ge15 formed another separate cluster within the genus Bacillus. 16S rRNA gene sequence similarities with type strains of other Bacillus species were less than 97 %. Levels of DNA-DNA relatedness among the four strains showed that strains ge09 and ge10(T) and strains ge14(T) and ge15 belonged to two separate species; the mean level of DNA-DNA relatedness between ge10(T) and ge14(T) was only 28.7 %. Their phenotypic and physiological properties supported the view that the two strains represent two different novel species of the genus Bacillus. The DNA G+C contents of strains ge10(T) and ge14(T) were 49.9 and 49.6 mol%, respectively. Strains ge10(T) and ge14(T) showed the peptidoglycan type A4alpha l-Lys-d-Glu. The lipids present in strains ge10(T) and ge14(T) were diphosphatidylglycerol, phosphatidylglycerol, a minor amount of phosphatidylcholine and two unknown phospholipids. Their predominant respiratory quinone was MK-7. The fatty acid profiles of the four novel strains contained large quantities of branched and saturated fatty acids. The predominant cellular fatty acids were iso-C(15 : 0) (42.5 %), anteiso-C(15 : 0) (22.2 %), anteiso-C(17 : 0) (7.3 %) and C(16 : 1)omega7c alcohol (5.7 %) in ge10(T) and iso-C(15 : 0) (50.7 %) and anteiso-C(15 : 0) (20.1 %) in ge14(T). On the basis of their phenotypic properties and phylogenetic distinctiveness, two novel species of the genus Bacillus are proposed, Bacillus beijingensis sp. nov. (type strain ge10(T) =DSM 19037(T) =CGMCC 1.6762(T)) and Bacillus ginsengi sp. nov. (type strain ge14(T) =DSM 19038(T) =CGMCC 1.6763(T)). PMID:19329597

Qiu, Fubin; Zhang, Xiaoxia; Liu, Lin; Sun, Lei; Schumann, Peter; Song, Wei

2009-04-01

280

Isolation and genetic identification of PAH degrading bacteria from a microbial consortium.  

PubMed

Polycyclic aromatic hydrocarbons (PAH; naphthalene, anthracene and phenanthrene) degrading microbial consortium C2PL05 was obtained from a sandy soil chronically exposed to petroleum products, collected from a petrochemical complex in Puertollano (Ciudad Real, Spain). The consortium C2PL05 was highly efficient degrading completely naphthalene, phenanthrene and anthracene in around 18 days of cultivation. The toxicity (Microtox method) generated by the PAH and by the intermediate metabolites was reduced to levels close to non-toxic in almost 40 days of cultivation. The identified bacteria from the contaminated soil belonged to gamma-proteobacteria and could be include in Enterobacter and Pseudomonas genus. DGGE analysis revealed uncultured Stenotrophomonas ribotypes as a possible PAH degrader in the microbial consortium. The present work shows the potential use of these microorganisms and the total consortium for the bioremediation of PAH polluted areas since the biodegradation of these chemicals takes place along with a significant decrease in toxicity. PMID:19468841

Molina, M Carmen; Gonzlez, Natalia; Bautista, L Fernando; Sanz, Raquel; Simarro, Raquel; Snchez, Irene; Sanz, Jos L

2009-11-01

281

Synthesis and structural characterization of Pd(II) complexes derived from perimidine ligand and their in vitro antimicrobial studies  

NASA Astrophysics Data System (ADS)

A novel series of Pd(II) complexes derived from 2-thiophenecarboxaldehyde and 1,8-diaminonaphthalene has been synthesized and characterized by various physico-chemical and spectroscopic techniques viz., elemental analyses, IR, UV-vis, 1H and 13C NMR spectroscopy, and ESI-mass spectrometry. The structure of ligand, 2-(2-thienyl)-2,3-dihydro-1H-perimidine has been ascertained on the basis of single crystal X-ray diffraction. All Pd(II) complexes together with the corresponding ligand have been evaluated for their ability to suppress the in vitro growth of microbes, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Citrobacter sp., Bacillus subtilis and Stenotrophomonas acidaminiphila and results show that Pd(II) complexes have more significant antimicrobial activity than their corresponding ligand. Fluorescence spectroscopic measurements clearly support that both of the Pd(II) complexes show significant DNA binding with calf thymus DNA.

Azam, Mohammad; Warad, Ismail; Al-Resayes, Saud I.; Alzaqri, Nabil; Khan, Mohammad Rizwan; Pallepogu, Raghavaiah; Dwivedi, Sourabh; Musarrat, Javed; Shakir, Mohammad

2013-09-01

282

Bacteria-mediated aerobic degradation of hexacosane in vitro conditions.  

PubMed

In vitro degradation of hexacosane (C26H54), a HMW n-alkane, was studied in MSM by two bacterial strains i.e., Pseudomonas sp. BP10 and Stenotrophomonas nitritireducens E9, isolated from petroleum sludge, in isolation and combination. The results revealed that both the strains were able to metabolize hexacosane by 82% in isolation and 98% in their consortium after 7days. An enhancement of 16% in hexacosane degradation by the consortium indicated an additive action of bacterial strains. However, in control, a degradation of 21% was attributed to abiotic factors. During incubation with hexacosane, both the bacteria continued to multiply in isolation and consortium, which reflected that hexacosane was utilized by bacteria as a carbon and energy source. Activities of alkane hydroxylase and alcohol dehydrogenase were differentially expressed in isolation and combination, indicating their involvement in hexacosane degradation. Enhanced cell surface hydrophobicity and emulsification index and reduced surface tension also supported the degradation process. PMID:25125193

Jauhari, Nitanshi; Mishra, Shweta; Kumari, Babita; Singh, S N

2014-10-01

283

Isolation of a selected microbial consortium capable of degrading methyl parathion and p-nitrophenol from a contaminated soil site.  

PubMed

A bacterial consortium with the ability to degrade methyl parathion and p-nitrophenol, using these compounds as the only carbon source, was obtained by selective enrichment in a medium with methyl parathion. Samples were taken from Moravia, Medellin; an area that is highly contaminated, owing to the fact that it was used as a garbage dump from 1974 to 1982. Acinetobacter sp, Pseudomonas putida, Bacillus sp, Pseudomonas aeruginosa Citrobacter freundii, Stenotrophomonas sp, Flavobacterium sp, Proteus vulgaris, Pseudomonas sp, Acinetobacter sp, Klebsiella sp and Proteus sp were the microorganisms identified within the consortium. In culture, the consortium was able to degrade 150 mg L? of methyl-parathion and p-nitrophenol in 120 h, but after adding glucose or peptone to the culture, the time of degradation decreased to 24 h. In soil, the consortium was also able to degrade 150 mg L? of methyl parathion in 120 h at different depths and also managed to decrease the toxicity. PMID:21328125

Pino, Nancy J; Dominguez, Maria C; Penuela, Gustavo A

2011-01-01

284

[Biodegradation of polyhydroxyalkanoates by soil microbiocoenoses of different structures and detection of microorganisms-destructors].  

PubMed

Biodegradation of microbial linear polymers of hydroxyalkanoic acids (polyhydroxyalkanoates, PHAs) by soil microbiocoenoses of different structures has been studied during two field seasons in different weather conditions. This process was shown to be influenced by the polymer chemical composition, temperature, humidity, and the microbial soil component. The PHA degradation was accompanied by a decrease in the polymer molecular weight and an increase in the degree of crystallinity, indicating the preferential destruction of the amorphous phase compared to the crystalline one. The quantity of the true PHA destructors developing at the surface of the polymer samples was lower than the quantity of accompanying bacteria. The dominant PHA destructors under the test conditions were identified as bacteria of the genera Variovorax, Stenotrophomonas, Acinetobacter, Pseudomonas, Bacillus, and Xanthomonas and as micromycetes from Penicillium, Paecilomyces, Acremonium, Verticillium. and Zygosporium. PMID:22567883

Boiandin, A N; Prudnikova, S V; Filipenko, M L; Khrapov, E A; Vasil'ev, A D; Volova, T G

2012-01-01

285

ESTIMATING BACTERIAL DIVERSITY IN SCIRTOTHRIPS DORSALIS (THYSANOPTERA: THRIPIDAE) VIA NEXT GENERATION SEQUENCING.  

PubMed

The last 2 decades have produced a better understanding of insect-microbial associations and yielded some important opportunities for insect control. However, most of our knowledge comes from model systems. Thrips (Thysanoptera: Thripidae) have been understudied despite their global importance as invasive species, plant pests and disease vectors. Using a culture and primer independent next-generation sequencing and metagenomics pipeline, we surveyed the bacteria of the globally important pest, Scirtothrips dorsalis Hood. The most abundant bacterial phyla identified were Actinobacteria and Proteobacteria and the most abundant genera were Propionibacterium, Stenotrophomonas, and Pseudomonas. A total of 189 genera of bacteria were identified. The absence of any vertically transferred symbiont taxa commonly found in insects is consistent with other studies suggesting that thrips primarilly acquire resident microbes from their environment. This does not preclude a possible beneficial/intimate association between S. dorsalis and the dominant taxa identified and future work should determine the nature of these associations. PMID:25382863

Dickey, Aaron M; Trease, Andrew J; Jara-Cavieres, Antonella; Kumar, Vivek; Christenson, Matthew K; Potluri, Lakshmi-Prasad; Morgan, J Kent; Shatters, Robert G; Mckenzie, Cindy L; Davis, Paul H; Osborne, Lance S

2014-06-01

286

Endophytic bacteria in Coffea arabica L.  

PubMed

Eighty-seven culturable endophytic bacterial isolates in 19 genera were obtained from coffee plants collected in Colombia (n = 67), Hawaii (n = 17), and Mexico (n = 3). Both Gram positive and Gram negative bacteria were isolated, with a greater percentage (68%) being Gram negative. Tissues yielding bacterial endophytes included adult plant leaves, various parts of the berry (e.g., crown, pulp, peduncle and seed), and leaves, stems, and roots of seedlings. Some of the bacteria also occurred as epiphytes. The highest number of bacteria among the berry tissues sampled was isolated from the seed, and includes Bacillus , Burkholderia , Clavibacter , Curtobacterium , Escherichia , Micrococcus , Pantoea , Pseudomonas , Serratia , and Stenotrophomonas . This is the first survey of the endophytic bacteria diversity in various coffee tissues, and the first study reporting endophytic bacteria in coffee seeds. The possible role for these bacteria in the biology of the coffee plant remains unknown. PMID:16187260

Vega, Fernando E; Pava-Ripoll, Monica; Posada, Francisco; Buyer, Jeffrey S

2005-01-01

287

Characterization of bacterial communities in hybrid upflow anaerobic sludge blanket (UASB)-membrane bioreactor (MBR) process for berberine antibiotic wastewater treatment.  

PubMed

Biodegradation of berberine antibiotic was investigated in upflow anaerobic sludge blanket (UASB)-membrane bioreactor (MBR) process. After 118days of operation, 99.0%, 98.0% and 98.0% overall removals of berberine, COD and NH4(+)-N were achieved, respectively. The detailed composition of the established bacterial communities was studied by using 16S rDNA clone library. Totally, 400 clones were retrieved and grouped into 186 operational taxonomic units (OTUs). UASB was dominated by Firmicutes and Bacteroidetes, while Proteobacteria, especially Alpha- and Beta-proteobacteria were prevalent in the MBRs. Clostridium, Eubacterium and Synergistes in the UASB, as well as Hydrogenophaga, Azoarcus, Sphingomonas, Stenotrophomonas, Shinella and Alcaligenes in the MBRs were identified as potential functional species in biodegradation of berberine and/or its metabolites. The bacterial community compositions in two MBRs were significantly discrepant. However, the identical functions of the functional species ensured the comparable pollutant removal performances in two bioreactors. PMID:23735790

Qiu, Guanglei; Song, Yong-Hui; Zeng, Ping; Duan, Liang; Xiao, Shuhu

2013-08-01

288

Highly sensitive determination of ectoine and other compatible solutes by anion-exchange chromatography and pulsed amperometric detection.  

PubMed

In saline media prokaryotes compensate for the osmotic pressure of the surrounding medium by producing osmolytes. Although these osmolytes or osmoprotectors have quite diverse structures, most of them can be determined by anion-exchange chromatography combined with integrated pulsed amperometric detection. This technique offers the advantages of very high sensitivity and new opportunities to determine ectoine and 5-hydroxyectoine-two important osmolytes -after hydrolytic cleavage of the pyrimidine ring. It can even be used to screen bacterial colonies on agar for compatible solutes. Furthermore, it allows amino acids and osmolytes of this type to be determined without derivatization. To test the method we applied it to two halotolerant bacterial strains: Stenotrophomonas rhizophila DSM 14405(T) and Halomonas elongata DSM 2581(T). The first strain produced trehalose and glucosylglycerol, and the second ectoine, as the main osmotic counterweight. The relationship between the content of these osmolytes in the bacterial biomass and the external salinity is described. PMID:12851735

Riis, Volker; Maskow, Thomas; Babel, Wolfgang

2003-09-01

289

Biodegradation potential of oily sludge by pure and mixed bacterial cultures.  

PubMed

The biodegradation capacity of aliphatic and aromatic hydrocarbons of petrochemical oily sludge in liquid medium by a bacterial consortium and five pure bacterial cultures was analyzed. Three bacteria isolated from petrochemical oily sludge, identified as Stenotrophomonas acidaminiphila, Bacillus megaterium and Bacillus cibi, and two bacteria isolated from a soil contaminated by petrochemical waste, identified as Pseudomonas aeruginosa and Bacillus cereus demonstrated efficiency in oily sludge degradation when cultivated during 40 days. The bacterial consortium demonstrated an excellent oily sludge degradation capacity, reducing 90.7% of the aliphatic fraction and 51.8% of the aromatic fraction, as well as biosurfactant production capacity, achieving 39.4% reduction of surface tension of the culture medium and an emulsifying activity of 55.1%. The results indicated that the bacterial consortium has potential to be applied in bioremediation of petrochemical oily sludge contaminated environments, favoring the reduction of environmental passives and increasing industrial productivity. PMID:21993328

Cerqueira, Vanessa S; Hollenbach, Emanuel B; Maboni, Franciele; Vainstein, Marilene H; Camargo, Flvio A O; do Carmo R Peralba, Maria; Bento, Ftima M

2011-12-01

290

The microbiome and emerging pathogens in cystic fibrosis and non-cystic fibrosis bronchiectasis.  

PubMed

Chronic pulmonary sepsis is the predominant cause of morbidity for patients with cystic fibrosis (CF) and non-CF bronchiectasis. Previously it was thought that respiratory infection in these patients was mostly limited to a very small number of typical pathogens; however, in recent years there have been increasing reports of infection with other emerging potential pathogens including Burkholderia, Stenotrophomonas, Achromobacter, Ralstonia, Pandoraea, nontuberculous mycobacteria, and fungal species. Furthermore, culture-independent methodologies have established that the lungs of patients with CF and non-CF bronchiectasis comprise mixed microbiological communities of aerobic and anaerobic bacteria, fungal and viral species, collectively referred to as the lung microbiome. This article addresses the clinical relevance of emerging pathogens and the lung microbiome in CF and non-CF bronchiectasis. PMID:25826590

Green, Heather; Jones, Andrew M

2015-04-01

291

Wastewater Irrigation Increases the Abundance of Potentially Harmful Gammaproteobacteria in Soils in Mezquital Valley, Mexico  

PubMed Central

Wastewater contains large amounts of pharmaceuticals, pathogens, and antimicrobial resistance determinants. Only a little is known about the dissemination of resistance determinants and changes in soil microbial communities affected by wastewater irrigation. Community DNAs from Mezquital Valley soils under irrigation with untreated wastewater for 0 to 100 years were analyzed by quantitative real-time PCR for the presence of sul genes, encoding resistance to sulfonamides. Amplicon sequencing of bacterial 16S rRNA genes from community DNAs from soils irrigated for 0, 8, 10, 85, and 100 years was performed and revealed a 14% increase of the relative abundance of Proteobacteria in rainy season soils and a 26.7% increase in dry season soils for soils irrigated for 100 years with wastewater. In particular, Gammaproteobacteria, including potential pathogens, such as Pseudomonas, Stenotrophomonas, and Acinetobacter spp., were found in wastewater-irrigated fields. 16S rRNA gene sequencing of 96 isolates from soils irrigated with wastewater for 100 years (48 from dry and 48 from rainy season soils) revealed that 46% were affiliated with the Gammaproteobacteria (mainly potentially pathogenic Stenotrophomonas strains) and 50% with the Bacilli, whereas all 96 isolates from rain-fed soils (48 from dry and 48 from rainy season soils) were affiliated with the Bacilli. Up to six types of antibiotic resistance were found in isolates from wastewater-irrigated soils; sulfamethoxazole resistance was the most abundant (33.3% of the isolates), followed by oxacillin resistance (21.9% of the isolates). In summary, we detected an increase of potentially harmful bacteria and a larger incidence of resistance determinants in wastewater-irrigated soils, which might result in health risks for farm workers and consumers of wastewater-irrigated crops. PMID:24951788

Broszat, Melanie; Nacke, Heiko; Blasi, Ronja; Siebe, Christina; Huebner, Johannes; Daniel, Rolf

2014-01-01

292

Isolation and characterization of plant growth-promoting rhizobacteria from wheat rhizosphere and their effect on plant growth promotion  

PubMed Central

The present study was conducted to characterize the native plant growth promoting (PGP) bacteria from wheat rhizosphere and root-endosphere in the Himalayan region of Rawalakot, Azad Jammu and Kashmir (AJK), Pakistan. Nine bacterial isolates were purified, screened in vitro for PGP characteristics and evaluated for their beneficial effects on the early growth of wheat (Triticum aestivum L.). Among nine bacterial isolates, seven were able to produce indole-3- acetic acid in tryptophan-supplemented medium; seven were nitrogen fixer, and four were able to solubilize inorganic phosphate in vitro. Four different morphotypes were genotypically identified based on IGS-RFLP fingerprinting and representative of each morphotype was identified by 16S rRNA gene sequencing analysis except Gram-positive putative Bacillus sp. Based on 16S rRNA gene sequence analysis, bacterial isolates AJK-3 and AJK-9 showing multiple PGP-traits were identified as Stenotrophomonas spp. while AJK-7 showed equal homologies to Acetobacter pasteurianus and Stenotrophomonas specie. Plant inoculation studies indicated that these Plant growth-promoting rhizobacteria (PGPR) strains provided a significant increase in shoot and root length, and shoot and root biomass. A significant increase in shoot N contents (up to 76%) and root N contents (up to 32%) was observed over the un-inoculated control. The study indicates the potential of these PGPR for inoculums production or biofertilizers for enhancing growth and nutrient content of wheat and other crops under field conditions. The study is the first report of wheat associated bacterial diversity in the Himalayan region of Rawalakot, AJK. PMID:25852661

Majeed, Afshan; Hameed, Sohail; Imran, Asma; Rahim, Nasir

2015-01-01

293

The Effects of Mary Rose Conservation Treatment on Iron Oxidation Processes and Microbial Communities Contributing to Acid Production in Marine Archaeological Timbers  

PubMed Central

The Tudor warship the Mary Rose has reached an important transition point in her conservation. The 19 year long process of spraying with polyethylene glycol (PEG) has been completed (April 29th 2013) and the hull is air drying under tightly controlled conditions. Acidophilic bacteria capable of oxidising iron and sulfur have been previously identified and enriched from unpreserved timbers of the Mary Rose, demonstrating that biological pathways of iron and sulfur oxidization existed potentially in this wood, before preservation with PEG. This study was designed to establish if the recycled PEG spray system was a reservoir of microorganisms capable of iron and sulfur oxidization during preservation of the Mary Rose. Microbial enrichments derived from PEG impregnated biofilm collected from underneath the Mary Rose hull, were examined to better understand the processes of cycling of iron. X-ray absorption spectroscopy was utilised to demonstrate the biological contribution to production of sulfuric acid in the wood. Using molecular microbiological techniques to examine these enrichment cultures, PEG was found to mediate a shift in the microbial community from a co-culture of Stenotrophomonas and Brevunidimonas sp, to a co-culture of Stenotrophomonas and the iron oxidising Alicyclobacillus sp. Evidence is presented that PEG is not an inert substance in relation to the redox cycling of iron. This is the first demonstration that solutions of PEG used in the conservation of the Mary Rose are promoting the oxidation of ferrous iron in acidic solutions, in which spontaneous abiotic oxidation does not occur in water. Critically, these results suggest PEG mediated redox cycling of iron between valence states in solutions of 75% PEG 200 and 50% PEG 2000 (v/v) at pH 3.0, with serious implications for the future use of PEG as a conservation material of iron rich wooden archaeological artefacts. PMID:24586230

Preston, Joanne; Smith, Andrew D.; Schofield, Eleanor J.; Chadwick, Alan V.; Jones, Mark A.; Watts, Joy E. M.

2014-01-01

294

Caldicellulosiruptor changbaiensis sp. nov., a cellulolytic and hydrogen-producing bacterium from a hot spring.  

PubMed

A novel thermophilic bacterial strain, CBS-Z(T), was isolated from a terrestrial hot spring in the Changbai Mountains, PR China. Cells of strain CBS-Z(T) were short straight rods without flagella and had Gram-positive cell walls. Growth was observed at 40-90 C (optimum 75 C) and at pH 5.6-8.6 (optimum pH 7.8). The primary end-products from the fermentation of filter paper by strain CBS-Z(T) were acetate, lactate, H2, and CO2. The main cellular fatty acids were iso-C17:0, iso-C14:0 3-OH and C16:0. The G+C content of the genomic DNA was 36.08 mol%. Multiple sequence alignment of the 16S rRNA gene sequence and phylogenetic analyses indicated that strain CBS-Z(T) belongs to the genus Caldicellulosiruptor and the most similar micro-organism was Caldicellulosiruptor saccharolyticus DSM 8903(T) (96.36% 16S rRNA gene sequence similarity); the 16S rRNA gene sequence similarity of strain CBS-Z(T) to other species was below 95%. Based on its phylogenetic and phenotypic characteristics, strain CBS-Z(T) represents a novel species of the genus Caldicellulosiruptor, for which the name Caldicellulosiruptor changbaiensis sp. nov. is proposed. The type strain is CBS-Z(T) (?=DSM 26941(T)?=CGMCC 1.5180(T)). PMID:25342112

Bing, Wei; Wang, Honglei; Zheng, Baisong; Zhang, Feng; Zhu, Guangshan; Feng, Yan; Zhang, Zuoming

2015-01-01

295

Actinoalloteichus nanshanensis sp. nov., isolated from the rhizosphere of a fig tree (Ficus religiosa).  

PubMed

A Gram-positive, aerobic actinomycete, designated strain NEAU 119(T), was isolated from the rhizosphere of a fig tree and was characterized using a polyphasic approach. The isolate formed branching, non-fragmenting vegetative hyphae and produced black pigment on yeast extract/malt extract (ISP medium 2). The G+C content of the DNA was 76.6 mol%. The organism had chemotaxonomic characteristics typical of the genus Actinoalloteichus and was closely related to the type strains of Actinoalloteichus cyanogriseus, Actinoalloteichus spitiensis and Actinoalloteichus hymeniacidonis, currently the only three recognized species of the genus Actinoalloteichus, sharing 16S rRNA gene similarities of 96.4, 96.6 and 98.1 %, respectively. However, the results of DNA-DNA hybridization studies demonstrated that the novel strain showed only 46.8 % relatedness with the type strain of A. hymeniacidonis. In addition, a set of phenotypic characteristics also readily distinguished strain NEAU 119(T) from the type strains of recognized species of the genus Actinoalloteichus. According to the above data, it is proposed that strain NEAU 119(T) represents a novel species, Actinoalloteichus nanshanensis sp. nov. The type strain of Actinoalloteichus nanshanensis is NEAU 119(T) (?=?CGMCC 4.5714(T)?=?NBRC 106685(T)). PMID:20562245

Xiang, Wensheng; Liu, Chongxi; Wang, Xiangjing; Du, Jing; Xi, Lijun; Huang, Ying

2011-05-01

296

Epilithonimonas xixisoli sp. nov., isolated from wetland bank-side soil.  

PubMed

A novel Gram-staining-negative, non-motile and rod-shaped bacterial strain containing flexirubin-type pigments, designated S31(T), was isolated from bank-side soil of the Xixi wetland in Zhejiang province, China. Growth occurred at 10-37 C (optimum, 32 C), pH 6-8 (optimum, pH 7) and with 0-2?% (w/v) NaCl (optimum, 1?%). Strain S31(T) shared highest 16S rRNA gene sequence similarities with Epilithonimonas lactis H1(T) (96.2?%) and Chryseobacterium molle DW3(T) (96.4?%). Phylogenetic analysis suggested that strain S31(T) was a member of the genus Epilithonimonas. The dominant respiratory quinone was MK-6 and the DNA G+C content was 33.3 mol%. The major fatty acids were iso-C15?:?0, summed feature 3 (iso-C15?:?0 2-OH and/or C16?:?1?7c) and anteiso-C15?:?0. The major polar lipids of strain S31(T) were phosphatidylethanolamine, three unidentified aminolipids and four unidentified polar lipids. Based on its phenotypic and chemotaxonomic characteristics and phylogenetic data, strain S31(T) represents a novel species of the genus Epilithonimonas, for which the name Epilithonimonas xixisoli sp. nov. (type strain S31(T)?=?CGMCC 1.12802(T)?=?NBRC 110387(T)) is proposed. PMID:25256707

Feng, Hao; Zeng, Yanhua; Huang, Yili

2014-12-01

297

Optimization of the condition for adsorption of gallic acid by Aspergillus oryzae mycelia using Box-Behnken design.  

PubMed

Fresh biomass of Aspergillus oryzae (A. oryzae) CGMCC5992 can effectively remove gallic acid from aqueous solution. To improve the removal rate of gallic acid, this study first identified the important factors affecting the removal rate of gallic acid with univariate analysis, and then used four-factor and three-level Box-Behnken design (BBD) with the removal rate of gallic acid as response value, to obtain the optimum conditions for the removal of gallic acid as follows: 6.95 h treatment time, pH 3.70, 7.07 g/L mycelium volume, and 120.64 mg/L initial concentration of gallic acid. Under such optimized condition, the removal rate of gallic acid approached 99.21 %. HPLC-MS analysis proved that the gallic acid in aqueous solution was completely removed by A. oryzae, rather than being metabolized into its derivatives. Scanning electron microscopy (SEM) indicated that the biomass morphology and surface structure of A. oryzae changed after the adsorption of gallic acid. Thus, the present study has provided an optimal condition for A. oryzae removal of gallic acid in water. PMID:25109471

Zhang, Zhicai; Pang, Qiaoxia; Li, Min; Zheng, Huihua; Chen, Hui; Chen, Keping

2015-01-01

298

Bacterioplanes sanyensis gen. nov., sp. nov., a PHB-accumulating bacterium isolated from a pool of Spirulina platensis cultivation.  

PubMed

A Gram-negative, poly-3-hydroxybutyrate-accumulating rod bacterium, strain GYP-2(T), was isolated from a pool of marine Spirulina platensis cultivation, Sanya, China. Growth was observed at 10-45 C and pH 6-10 in the presence of 1-10 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the new isolate belonged to Gammaproteobacteria and displayed 93.8-95.3 % 16S rRNA gene sequences similarities to members of the genera Thalassolituus, Oleibacter, and Oceanobacter, but house-keeping gene gyrB (encode DNA gyrase beta subunit) demonstrated that the new isolate was distantly related to Thalassolituus, Oleibacter, and Oceanobacter species (only 77-83 % gene gyrB sequences similarities).The G+C content of genomic DNA was 55 mol%. The major respiratory quinone was Q-9, while that for Oceanobacter kriegii LMG 6238(T) was Q-8. Major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. On the basis of its physiological, chemotaxonomic, and molecular properties, strain GYP-2(T) is suggested to represent a novel species of a new genus in Gammaproteobacteria, for which the name Bacterioplanes sanyensis gen. nov., sp. nov. is proposed. The type strain is GYP-2(T) (=CGMCC 1.12392(T)=KCTC 32220(T)). PMID:25038945

Wang, Guanghua; Jia, Qikun; Li, Tao; Dai, Shikun; Wu, Huanlian; He, Hui; Fan, Jiewei; Xiang, Wenzhou; Li, Xiang

2014-10-01

299

Streptomyces heilongjiangensis sp. nov., a novel actinomycete that produces borrelidin isolated from the root surface of soybean [Glycine max (L.) Merr  

PubMed Central

A borrelidin-producing actinomycete, designated strain NEAU-W2T, was isolated from the root surface of soybean [Glycine max (L.) Merr] and characterized using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of streptomycetes. The G+C content of the DNA was 66.12 mol%. Analysis of the 16S rRNA gene sequence of strain NEAU-W2T revealed that the strain formed a distinct clade within the 16S rRNA gene sequence phylogenetic tree and showed highest similarity (99.61?%) to Streptomyces neyagawaensis ATCC 27449T. However, the DNADNA relatedness between strain NEAU-W2T and S. neyagawaensis ATCC 27449T was 58.51?%. Strain NEAU-W2T could also be differentiated from S. neyagawaensis ATCC 27449T and other Streptomyces species showing high 16S rRNA gene sequence similarity (9899?%), as well as other borrelidin-producing strains, based on morphological and physiological characteristics. On the basis of its physiological and molecular properties, it is proposed that strain NEAU-W2T represents a novel Streptomyces species, Streptomyces heilongjiangensis sp. nov. The type strain is NEAU-W2T (?=?CGMCC 4.7004T ?=?ATCC BAA-2424T ?=?DSM 42073T). PMID:22707527

Liu, Chongxi; Wang, Xiangjing; Yan, Yijun; Wang, Jidong; Zhang, Bo; Zhang, Ji

2013-01-01

300

Nonomuraea solani sp. nov., an actinomycete isolated from eggplant root (Solanum melongena L.)  

PubMed Central

A novel actinomycete, designated strain NEAU-Z6T, was isolated from eggplant (Solanum melongena L.) root. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain NEAU-Z6T belonged to the genus Nonomuraea, with highest sequence similarity to Nonomuraea monospora PT 708T (98.83?%), Nonomuraea rosea GW 12687T (98.55?%) and Nonomuraea rhizophila YIM 67092T (98.02?%). Sequence similarities between strain NEAU-Z6T and other species of the genus Nonomuraea ranged from 97.94?% (Nonomuraea candida HMC10T) to 96.30?% (Nonomuraea wenchangensis 210417T). Key morphological, physiological and chemotaxonomic characteristics of strain NEAU-Z6T were congruent with the description of the genus Nonomuraea. The G+C content of the genomic DNA was 64.51 mol%. DNADNA relatedness and comparative analysis of physiological, biochemical and chemotaxonomic data allowed genotypic and phenotypic differentiation of strain NEAU-Z6T from closely related species. Thus, strain NEAU-Z6T represents a novel species of the genus Nonomuraea, for which the name Nonomuraea solani sp. nov. is proposed. The type strain is NEAU-Z6T (?=?CGMCC 4.7037T?=?DSM 45729T). PMID:23203622

Wang, Xiangjing; Zhao, Junwei; Liu, Chongxi; Wang, Jidong; Shen, Yue; Jia, Feiyu; Wang, Liang; Zhang, Ji; Yu, Chao

2013-01-01

301

Paracoccus tibetensis sp. nov., isolated from Qinghai-Tibet Plateau permafrost.  

PubMed

Strain Tibet-S9a3(T) was isolated from Qinghai-Tibet Plateau permafrost, China. The isolate was a Gram-negative, non-motile, non-spore-forming short rod. The 16S rRNA gene sequence indicated that strain Tibet-S9a3(T) was a member of the genus Paracoccus and was closely related to Paracoccus aestuarii B7(T) (98.2?% 16S rRNA gene sequence similarity), 'P. beibuensis' JLT1284 (97.9?%), P. homiensis DD-R11(T) (97.4?%), P. zeaxanthinifaciens ATCC 21588(T) (97.4?%) and other type strains of the genus (93.7-96.7?%). The G+C content of the genomic DNA was 69.1 mol% and the major isoprenoid quinone was ubiquinone-10. The major fatty acids were C18?:?1?7c (87.6?%), C18?:?0 (4.3?%) and C10?:?0 3-OH (2.0?%). DNA-DNA relatedness between strain Tibet-S9a3(T) and P. aestuarii B7(T) was 37.9?%. On the basis of phenotypic and genotypic characteristics, it is suggested that strain Tibet-S9a3(T) represents a novel species of the genus Paracoccus, for which the name Paracoccus tibetensis sp. nov. is proposed. The type strain is Tibet-S9a3(T) (?=?CGMCC 1.8925(T) ?=?NBRC 105667(T)). PMID:23024140

Zhu, Shan; Zhao, Qi; Zhang, Gaosen; Jiang, Zhonghao; Sheng, Hongmei; Feng, Huyuan; An, Lizhe

2013-05-01

302

Hymenobacter qilianensis sp. nov., isolated from a subsurface sandstone sediment in the permafrost region of Qilian Mountains, China and emended description of the genus Hymenobacter.  

PubMed

A red-pink, Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, designated strain DK6-37 was isolated from the permafrost region of Qilian Mountains in northwest of China. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that this isolate represents a novel member of the genus Hymenobacter, with low sequence similarities (<97%) to recognized Hymenobacter species. Optimum growth was observed at 28C, pH 7.0 and 0% NaCl. The strain was found to contain MK-7 as the predominant menaquinone. The polar lipids were identified as phosphatidylethanolanmine, two unknown aminophospholipids, one unknown aminolipid and three unknown polar lipids. The major fatty acids were identified as summed feature 3 (C16:1 ?7c/C16:1 ?6c as defined by MIDI), summed feature 4 (anteiso-C17:1 B/iso-C17:1 I), C16:1 ?5c, iso-C17:0 3-OH, iso-C15:0 and C18:0. The DNA G+C content was determined to be 67.4mol%. On the basis of the polyphasic evidence presented, it is proposed that strain DK6-37 represents a novel species of the genus Hymenobacter, for which the name Hymenobacter qilianensis sp. nov. is proposed. The type strain is DK6-37(T) (=CGMCC 1.12720(T)=JCM 19763(T)). PMID:24677143

Han, Lu; Wu, Shu-Jiao; Qin, Chun-Yan; Zhu, You-Hai; Lu, Zhen-Quan; Xie, Bing; Lv, Jie

2014-05-01

303

An efficient blue-white screening based gene inactivation system for Streptomyces.  

PubMed

Streptomyces is studied intensively for its outstanding ability to produce bioactive secondary metabolites and for its complicated morphological differentiation process. A classical genetic manipulation system for Streptomyces has been developed and widely used in the community for a long time, using antibiotic resistance markers to select for double-crossover mutants. The screening process is always laborious and time-consuming. However, the lack of a suitable chromogenic reporter for Streptomyces has limited the use of color-based screening system to simplify the selection process for double-crossover mutants. In this study, a blue reporter system for Streptomyces has been established by mining an indigoidine synthetase gene (idgS) from Streptomyces lavendulae CGMCC 4.1386, leading to the development of a time-saving gene inactivation system for Streptomyces by simple blue-white screening. A series of Streptomyces suicide and temperature-sensitive plasmids containing the idgS reporter cassette were constructed and used successfully to inactivate genes in Streptomyces, allowing a simple and efficient screening method to differentiate the colonies for double-crossover (white) and single-crossover (blue) mutants. Inactivation of the putative ?-butyrolactone synthase gene afsA-y via the idgS-based blue-white screening method revealed that the paulomycin production is negatively controlled by afsA-y in Streptomyces sp. YN86. PMID:25666782

Li, Pengwei; Li, Jine; Guo, Zhengyan; Tang, Wei; Han, Jianshan; Meng, Xiangxi; Hao, Tingting; Zhu, Yaxin; Zhang, Lixin; Chen, Yihua

2015-02-01

304

Sinomicrobium pectinilyticum sp. nov., a pectinase-producing bacterium isolated from alkaline and saline soil, and emended description of the genus Sinomicrobium.  

PubMed

A Gram-reaction-negative, non-spore-forming strain, designated 5DNS001(T), was isolated from soil of an ancient salt-extracting facility in China. Analysis of the almost-complete 16S rRNA gene sequence of the bacterium suggested that it belongs to the genus Sinomicrobium in the family Flavobacteriaceae. It exhibited highest 16S rRNA gene sequence similarity with Sinomicrobium oceani SCSIO 03483(T) (96.3?%), but less than 93?% sequence similarity with members of the genera Imtechella, Zhouia and Joostella and other recognized members of the family Flavobacteriaceae. The strain was able to hydrolyse pectin and starch by producing pectinase and ?-amylase. The DNA G+C content of the strain was 42.6 mol%. The major respiratory quinone was MK-6. The major polar lipid detected in the strain was phosphatidylethanolamine. The dominant cellular fatty acids were iso-C15?:?0, iso-C17?:?0 3-OH and summed feature 3 (C16?:?1?6c/C16?:?1?7c). Based on phenotypic, genotypic, chemotaxonomic and phylogenetic analyses, a novel species, Sinomicrobium pectinilyticum, is proposed. The type strain is 5DNS001(T) (?=?CGMCC1.11000(T)?=?KCTC23776(T)). PMID:24912822

Cheng, Bin; Li, Chunfang; Lai, Qiliang; Du, Miaofen; Shao, Zongze; Xu, Ping; Yang, Chunyu

2014-09-01

305

Pseudooceanicola atlanticus gen. nov. sp. nov., isolated from surface seawater of the Atlantic Ocean and reclassification of Oceanicola batsensis, Oceanicola marinus, Oceanicola nitratireducens, Oceanicola nanhaiensis, Oceanicola antarcticus and Oceanicola flagellatus, as Pseudooceanicola batsensis comb. nov., Pseudooceanicola marinus comb. nov., Pseudooceanicola nitratireducens comb. nov., Pseudooceanicola nanhaiensis comb. nov., Pseudooceanicola antarcticus comb. nov., and Pseudooceanicola flagellatus comb. nov.  

PubMed

A taxonomic study was carried out on strain 22II-S11g(T), which was isolated from the surface seawater of the Atlantic Ocean. The bacterium was found to be Gram-negative, rod shaped without flagellum, oxidase positive and weakly catalase positive. Growth was observed at NaCl concentrations of 0.5-9% and at temperatures of 10-41C. The isolate was incapable of gelatin hydrolysis and unable to reduce nitrate to nitrite, degrade aesculin and Tween 80. On the basis of 16S rRNA gene sequence similarity, strain 22II-S11g(T) was found to be most closely related to Oceanicola batsensis HTCC2597(T) (97.26%), followed by Oceanicola nitratireducens JLT1210(T) (96.39%), whilst other species of genus Oceanicola shared 94.00-96.34% sequence similarity. However, it showed low similarity to Oceanicola granulosus HTCC2516(T) (94.79%), the type species of the genus Oceanicola. Phylogenetic analysis showed that strain 22II-S11g(T) formed a clade with six species currently classified in the genus Oceanicola, but strain O. granulosus HTCC2516(T) and strain O. litoreus M-M22(T) clustered with two other genera respectively. The ANI values between strain 22II-S11g(T) and two type strains (O. batsensis HTCC2597(T) and O. granulosus HTCC2516(T)) are 91.86 and 91.81% respectively. The digital DNA-DNA hybridization estimate values between strain 22II-S11g(T) and two type strains (O. batsensis HTCC2597(T) and O. granulosus HTCC2516(T)) are 23.42.4 and 20.02.3%, respectively. The principal fatty acids were identified as summed feature 8 (C18:1 ?7c/?6c), C16:0, C18:1 ?7c11-methyl and C12:0 3OH. The G+C content determined from the draft genome sequence is 64.1mol%. The respiratory quinone was determined to be Q-10 (100%). Phosphatidylethanolamine, phosphatidylglycerol, an aminolipid, phosphatidylcholine, a phospholipid and three lipids were identified in the polar lipids. The combined genotypic and phenotypic data also show that strain 22II-S11g(T) should not be assigned to the genus Oceanicola; consequently strain 22II-S11g(T) is concluded to represent a novel species of a novel genus in the family Rhodobacteraceae, for which the name Pseudooceanicola atlanticus gen. nov., sp. nov. is proposed (type strain 22II-S11g(T)=KCTC 42004(T)=LMG 27424(T)=MCCC 1A09160(T)). Six misclassified species should be transferred to the novel genus Pseudooceanicola as follows: O. batsensis should be transferred to the genus Pseudooceanicola as Pseudooceanicola batsensis comb. nov. (type strain HTCC2597(T)=ATCC BAA-863(T)=DSM 15984(T)=KCTC 12145(T)); Oceanicola marinus should be transferred to the genus Pseudooceanicola as Pseudooceanicola marinus comb. nov. (type strain AZO-C(T)=LMG 23705(T)=BCRC 17591(T)); O. nitratireducens should be transferred to the genus Pseudooceanicola as Pseudooceanicola nitratireducens comb. nov. (type strain JLT1210(T)=LMG 24663(T)=CGMCC 1.7292(T)); Oceanicola nanhaiensis should be transferred to the genus Pseudooceanicola as Pseudooceanicola nanhaiensis comb. nov. (type strain SS011B1-20(T)=LMG 23508(T)=CGMCC 1.6293(T)); Oceanicola antarcticus should be transferred to the genus Pseudooceanicola as Pseudooceanicola antarcticus comb. nov. (type strain Ar-45(T)=CGMCC 1.12662(T)=LMG 27868(T)); and Oceanicola flagellatus should be transferred to the genus Pseudooceanicola as Pseudooceanicola flagellatus comb. nov. (type strain DY470(T)=CGMCC 1.12664(T)=LMG 27871(T)). PMID:25663028

Lai, Qiliang; Li, Guizhen; Liu, Xiupian; Du, Yaping; Sun, Fengqin; Shao, Zongze

2015-04-01

306

Genomic sequencing identifies novel Bacillus thuringiensis Vip1/Vip2 binary and Cry8 toxins that have high toxicity to Scarabaeoidea larvae.  

PubMed

The Bacillus thuringiensis strain HBF-18 (CGMCC 2070), which has previously been shown to encode the cry8Ga toxin gene, is active against both Holotrichia oblita and Holotrichia parallela. Recombinant Cry8Ga however is only weakly toxic to these insect pests suggesting the involvement of additional toxins in the native strain. We report that through the use of Illumina sequencing three additional, and novel, genes, namely vip1Ad1, vip2Ag1, and cry8-like, were identified in this strain. Although no protein corresponding to these genes could be identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of the HBF-18 proteome, reverse transcription (RT)-PCR indicated that all three genes were transcribed in the native strain. The two vip genes were cloned and expressed and, as with other Vip1/2 toxins, appeared to function as a binary toxin and showed strong activity against H. oblita, H. parallela and Anomala corpulenta. This is the first report to demonstrate that the Vip1/Vip2 binary toxin is active against these Scarabaeoidea larvae. The cry8-like gene appeared to be a C-terminally truncated form of a typical cry8 gene and was not expressed in our usual recombinant Bt expression system. When however the missing C-terminal region was replaced with the corresponding sequence from cry8Ea, the resulting hybrid expressed well and the toxin was active against the three test insects. PMID:25081556

Bi, Yang; Zhang, Yanrui; Shu, Changlong; Crickmore, Neil; Wang, Qinglei; Du, Lixin; Song, Fuping; Zhang, Jie

2015-01-01

307

Luteimonas dalianensis sp. nov., an obligate marine bacterium isolated from seawater.  

PubMed

A marine bacterial strain, designated OB44-3(T), was isolated from a crude oil-contaminated seawater sample collected near Dalian Bay, China. Cells of strain OB44-3(T) were Gramnegative, aerobic, rod-shaped, and oxidase- and catalasepositive. The major fatty acids were branched-chain saturated iso-C15:0 (27.9%) and unsaturated iso-C17:1 ?9c (14.8%). The DNA G+C content was 64.6 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain OB44-3(T) was a member of the genus Luteimonas (95-96% 16S rRNA gene sequence similarity); its closest neighbors were the type strains of Luteimonas terricola (96% sequence similarity), Luteimonas mephitis (96%), and Luteimonas lutimaris (96%). On the basis of phenotypic, chemotaxonomic, and phylogenetic distinctiveness, strain OB44-3(T) was considered to represent a novel species of the genus Luteimonas. The name Luteimonas dalianensis sp. nov. is proposed, with strain OB44-3(T) (=CGMCC 1.12191(T) =JCM 18136(T)) as the type strain. PMID:25085731

Xin, Yanjuan; Cao, Xupeng; Wu, Peichun; Xue, Song

2014-09-01

308

Streptomyces heilongjiangensis sp. nov., a novel actinomycete that produces borrelidin isolated from the root surface of soybean [Glycine max (L.) Merr].  

PubMed

A borrelidin-producing actinomycete, designated strain NEAU-W2(T), was isolated from the root surface of soybean [Glycine max (L.) Merr] and characterized using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of streptomycetes. The G+C content of the DNA was 66.12 mol%. Analysis of the 16S rRNA gene sequence of strain NEAU-W2(T) revealed that the strain formed a distinct clade within the 16S rRNA gene sequence phylogenetic tree and showed highest similarity (99.61?%) to Streptomyces neyagawaensis ATCC 27449(T). However, the DNA-DNA relatedness between strain NEAU-W2(T) and S. neyagawaensis ATCC 27449(T) was 58.51?%. Strain NEAU-W2(T) could also be differentiated from S. neyagawaensis ATCC 27449(T) and other Streptomyces species showing high 16S rRNA gene sequence similarity (98-99?%), as well as other borrelidin-producing strains, based on morphological and physiological characteristics. On the basis of its physiological and molecular properties, it is proposed that strain NEAU-W2(T) represents a novel Streptomyces species, Streptomyces heilongjiangensis sp. nov. The type strain is NEAU-W2(T) (?=?CGMCC 4.7004(T) ?=?ATCC BAA-2424(T) ?=?DSM 42073(T)). PMID:22707527

Liu, Chongxi; Wang, Xiangjing; Yan, Yijun; Wang, Jidong; Zhang, Bo; Zhang, Ji; Xiang, Wensheng

2013-03-01

309

Natronorubrum sediminis sp. nov., an archaeon isolated from a saline lake.  

PubMed

Two novel haloalkaliphilic archaea, strains CG-6T and CG-4, were isolated from sediment of the hypersaline Lake Chagannor in Inner Mongolia, China. Cells of the two strains were pleomorphic, non-motile and strictly aerobic. They required at least 2.5 M NaCl for growth, with optimum growth at 3.4 M NaCl. They grew at pH 8.0-11.0, with optimum growth at pH 9.0. Hypotonic treatment with less than 1.5 M NaCl caused cell lysis. The two strains had similar polar lipid compositions, possessing C20C20 and C20C25 derivatives of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. No glycolipids were detected. Comparison of 16S rRNA gene sequences and morphological features placed them in the genus Natronorubrum. 16S rRNA gene sequence similarities to strains of recognized species of the genus Natronorubrum were 96.2-93.8%. Detailed phenotypic characterization and DNA-DNA hybridization studies revealed that the two strains belong to a novel species in the genus Natronorubrum, for which the name Natronorubrum sediminis sp. nov. is proposed; the type strain is CG-6T (=CECT 7487T =CGMCC 1.8981T =JCM 15982T). PMID:19767366

Gutirrez, M C; Castillo, A M; Corral, P; Minegishi, H; Ventosa, A

2010-08-01

310

Salinigranum rubrum gen. nov., sp. nov., a member of the family Halobacteriaceae isolated from a marine solar saltern.  

PubMed

Halophilic archaeal strain GX10(T) was isolated from the Gangxi marine solar saltern in China. Strain GX10(T) was observed to have pleomorphic cells that lysed in distilled water, stained Gram-negative and produced red-pigmented colonies. Strain GX10(T) was able to grow at 20-50 C (optimum 37 C), with 1.4-4.8 M NaCl (optimum 3.1 M NaCl), with 0-0.7 M MgCl2 (optimum 0.05 M MgCl2) and at pH 5.0-9.0 (optimum pH 7.0). The major polar lipids of strain GX10(T) were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, two major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether and mannosyl glucosyl diether, and five unidentified glycolipids. Phylogenetic tree reconstructions based on 16S rRNA gene and rpoB' sequences revealed that strain GX10(T) was distinct from the related genera, Halogranum, Haloferax, Halopelagius, Halogeometricum, Halobellus, Haloplanus and Halorubrum. The DNA G+C content of strain GX10(T) was 62.9 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain GX10(T) represents a novel species of a new genus within the family Halobacteriaceae, for which the name Salinigranum rubrum gen. nov., sp. nov. is proposed. The type strain of the type species is GX10(T) (?=?CGMCC 1.10385(T)?=?JCM 17116(T)). PMID:24651304

Cui, Heng-Lin; Zhang, Wen-Jiao

2014-06-01

311

Halomonas zincidurans sp. nov., a heavy-metal-tolerant bacterium isolated from the deep-sea environment.  

PubMed

A Gram-stain-negative, aerobic, rod-like, motile by peritrichous flagella and moderately halophilic bacterium, designated strain B6(T), was isolated a deep-sea sediment collected from the South Atlantic Ocean. The isolate grew with 0.5-15?% (w/v) NaCl, at 4-37 C and pH 5.0-8.5 and showed a high tolerance to zinc, manganese, cobalt and copper ions. The major fatty acids were C16?:?0, C19?:?0 cyclo ?8c, C12?:?0 3-OH and C12?:?0. The predominant ubiquinone was Q-9. The genomic DNA G+C content was 61.1 mol%. Phylogenetic analysis based on 16S rRNA gene comparisons indicated that strain B6(T) belonged to the genus Halomonas, and the closest relative was Halomonas xinjiangensis TRM 0175(T) (96.1?%). Based upon the phenotypic, chemotaxonomic and genetic data, strain B6(T) represents a novel species from the genus Halomonas, for which the name Halomonas zincidurans sp. nov. is proposed. The type strain is B6(T) (?=?CGMCC 1.12450(T)?=?JCM 18472(T)). PMID:23811134

Xu, Lin; Xu, Xue-Wei; Meng, Fan-Xu; Huo, Ying-Yi; Oren, Aharon; Yang, Jun-Yi; Wang, Chun-Sheng

2013-11-01

312

Salisediminibacterium halotolerans gen. nov., sp. nov., a halophilic bacterium from soda lake sediment.  

PubMed

An orange-pigmented, Gram-reaction-positive, non-spore-forming, halophilic, alkali-tolerant rod, designated strain halo-2(T), was isolated from sediment of Xiarinaoer soda lake, in China's Inner Mongolia Autonomous Region. Strain halo-2(T) grew in a complex medium with 3-30 % (w/v) NaCl and at pH 5-10. The cell-wall peptidoglycan contained meso-diaminopimelic acid and the major respiratory isoprenoid quinone was MK-7. The predominant cellular fatty acids were anteiso-C(15 : 0) (43.6 %), anteiso-C(17 : 0) (14.8 %) and iso-C(15 : 0) (6.8 %) and the polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The genomic DNA G+C content of the novel strain was 48.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain halo-2(T) was most closely related to Bacillus agaradhaerens DSM 8721(T) (93.9 % sequence similarity). However, strain halo-2(T) could be clearly differentiated from its closest phylogenetic relatives on the basis of several phenotypic, genotypic and chemotaxonomic characteristics. Strain halo-2(T) therefore represents a novel species in a new genus for which the name Salisediminibacterium halotolerans gen. nov., sp. nov. is proposed. The type strain of the type species is halo-2(T) (= CGMCC 1.7654(T) = NBRC 104935(T)). PMID:22039006

Jiang, Feng; Cao, Shu-Juan; Li, Zhao-Hu; Fan, Hua; Li, Hai-Feng; Liu, Wei-Jie; Yuan, Hong-Li

2012-09-01

313

Fabibacter pacificus sp. nov., a moderately halophilic bacterium isolated from seawater.  

PubMed

A Gram-stain-negative, aerobic, moderately halophilic bacterium, strain DY53(T), was isolated from a deep-seawater sample collected from the eastern Pacific Ocean. This isolate grew in the presence of 0.5-10.0?% (w/v) NaCl, at pH 6.5-8.5 and at 15-40 C. The optimum NaCl concentration for growth of DY53(T) was 2?% (w/v) at 35 C. Chemotaxonomic analysis showed MK-7 as the predominant menaquinone and iso-C15?:?0, summed feature 3 (iso-C15?:?0 2-OH and/or C16?:?1?7c), iso-C15?:?1 G, iso-C15?:?0 3-OH and iso-C17?:?0 3-OH as major cellular fatty acids. The genomic DNA G+C content was 40.8 mol%. Phylogenetic trees based on 16S rRNA gene sequences revealed that Fabibacter halotolerans UST030701-097(T) was the closest neighbour, with 96.7?% sequence similarity. Based on phylogenetic, chemotaxonomic and phenotypic data, we propose that strain DY53(T) represents a novel species of the genus Fabibacter, for which the name Fabibacter pacificus sp. nov. is proposed. The type strain is DY53(T)(?=?CGMCC 1.12402(T)?=?JCM 18885(T)). PMID:23625263

Huo, Ying-Yi; Xu, Lin; Wang, Chun-Sheng; Yang, Jun-Yi; You, Hong; Oren, Aharon; Xu, Xue-Wei

2013-10-01

314

Corynebacterium marinum sp. nov. isolated from coastal sediment.  

PubMed

A taxonomic study was performed on strain D7015T, which was isolated from coastal sediment close to a coal-fired power station in Qingdao, China. Cells of strain D7015T were Gram-positive, non-motile, diphtheroid rods that grew in the presence of 0-8% (w/v) NaCl and at 4-37 degrees C, with optimum growth at 1% (w/v) NaCl and 30-32 degrees C. The DNA G+C content was 65.0 mol%. The major fatty acids were C18:1omega9c (56.18%), C16:0 (38.02%), C16:1omega7c (4.45%), C18:0 (1.0%) and C14:0 (0.35%). On the basis of morphological, physiological and phylogenetic characteristics, strain D7015T was classified in the genus Corynebacterium. It exhibited a 16S rRNA gene sequence similarity of 95.9% and a DNA-DNA relatedness value of 20.4% with Corynebacterium halotolerans DSM 44683T. Strain D7015T was sufficiently different from recognized species of the genus Corynebacterium to be considered to represent a novel species. The name Corynebacterium marinum sp. nov. is proposed, with strain D7015T (=CGMCC 1.6998T=NRRL B-24779T) as the type strain. PMID:19783605

Du, Zong-Jun; Jordan, Elizabeth M; Rooney, Alejandro P; Chen, Guan-Jun; Austin, Brian

2010-08-01

315

Thermus arciformis sp. nov., a thermophilic species from a geothermal area.  

PubMed

Two aerobic, Gram-negative, non-motile, non-sporulating, yellow-pigmented bacteria, strains TH92(T) and TH91, were isolated from a hot spring located in Laibin, Guangxi, in the south-eastern geothermal area of China. The isolates grew at 40-77 degrees C (optimally at 70 degrees C) and at pH 6.0-9.5 (optimally at pH 7.5-8.0). Phylogenetic analysis of 16S rRNA gene sequences and levels of DNA-DNA relatedness together indicated that the new isolates represented a novel species of the genus Thermus with closest affinity to Thermus aquaticus, Thermus igniterrae and Thermus thermophilus. Compared with their closest relatives, strains TH92( T) and TH91 were able to assimilate a wider range of carbohydrates, amino acids and organic acids as sole carbon sources for growth, such as lactose and melibiose. The new isolates had lower combined levels of C(16 : 0 ) and iso-C(16 : 0) compared with their closest relatives. On the basis of polyphasic taxonomic characterization, strains TH92(T) and TH91 are considered to represent a single novel species of the genus Thermus, for which the name Thermus arciformis sp. nov. is proposed. The type strain is TH92(T) (=CGMCC 1.6992(T) =JCM 15153(T)). PMID:19661520

Zhang, Xin-Qi; Ying, Yi; Ye, Ying; Xu, Xue-Wei; Zhu, Xu-Fen; Wu, Min

2010-04-01

316

Flavihumibacter petaseus gen. nov., sp. nov., isolated from soil of a subtropical rainforest.  

PubMed

A yellow-coloured bacterium, T41(T), was isolated from a soil sample of a subtropical rainforest in Nepal. Cells were Gram-reaction-positive, aerobic, non-motile, short rods. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain formed a cluster with Terrimonas ferruginea, Terrimonas lutea, Niabella soli, Flavisolibacter ginsengiterrae, Flavisolibacter ginsengisoli, Niastella yeongjuensis and Niastella koreensis in the phylum Bacteroidetes. The strain showed the highest sequence similarity to the type strain of Terrimonas lutea (93.2 %). The major isoprenoid quinone was MK-7 and the predominant cellular fatty acids (>10 %) were iso-15 : 0 (33.8 %), iso-15 : 1 G (13.3 %) and iso-17 : 0 3-OH (12.9 %). The DNA G+C content was 48.1 mol%. On the basis of phenotypic and phylogenetic data and genomic distinctiveness, strain T41(T) represents a novel species in a new genus in the phylum Bacteroidetes, for which the name Flavihumibacter petaseus gen. nov., sp. nov. is proposed. The type strain of Flavihumibacter petaseus is strain T41(T) (=CGMCC 1.7723(T) =NBRC 106054(T)). PMID:19700449

Zhang, Nan Nan; Qu, Jian Hang; Yuan, Hong Li; Sun, Yan Mei; Yang, Jin Shui

2010-07-01

317

Saccharothrix carnea sp. nov., an actinobacterium isolated from soil.  

PubMed

A novel actinobacterium, designated strain NEAU-yn17(T), was isolated from a soil sample collected at the wastewater discharge site of a pesticide factory in Harbin, northern China, and characterized using a polyphasic approach. Morphological and chemotaxonomic properties of strain NEAU-yn17(T) were consistent with the description of the genus Saccharothrix, such as the spore arrangement, the diamino acid of the peptidoglycan, the whole-cell hydrolysates, the predominant menaquinone and the phospholipid profile. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that strain NEAU-yn17(T) should also be classified in the genus Saccharothrix, with Saccharothrix saharensis DSM 45456(T) (99.52?% sequence similarity) and Saccharothrix xinjiangensis JCM 12329(T) (99.04?%) as the nearest phylogenetic relatives. A combination of DNA-DNA hybridization results and some phenotypic characteristics indicated that strain NEAU-yn17(T) can be distinguished from its closest relatives. Therefore, strain NEAU-yn17(T) represents a novel species of the genus Saccharothrix, for which the name Saccharothrix carnea sp. nov. is proposed. The type strain is NEAU-yn17(T) (?=?CGMCC 4.7097(T)?=?DSM 45878(T)). PMID:25256705

Liu, Chongxi; Guan, Xuejiao; Wang, Shurui; Zhao, Junwei; Wang, Haiyan; He, Hairong; Xiang, Wensheng; Wang, Xiangjing

2014-12-01

318

Gryllotalpicola reticulitermitis sp. nov., isolated from a termite gut.  

PubMed

Strain TS-56(T) was isolated from the gut of a wood-feeding termite, Reticulitermes chinensis Snyder. Phylogenetic analyses based on 16S rRNA gene sequences revealed that the strain represented a member of the genus Gryllotalpicola of the family Microbacteriaceae, with sequence similarities to other species of the genus ranging from 96.6?% to 97.8?%. The isolate was Gram-stain-positive, non-motile, with light yellow colonies and irregular short rod-shaped cells (0.4-0.6 m in diameter, 0.6-1.0 m in length). Growth of TS-56(T) occurred at 20-35 C (optimum, 30 C) and at pH 4.0-8.0 (optimum, pH 5.0). The peptidoglycan of TS-56(T) contained ornithine, glutamic acid, alanine, homoserine and glycine. The acyl type was acetyl. The most abundant cellular fatty acid of TS-56(T) was cyclohexyl-C17?:?0 (88.79?%). The respiratory menaquinone was MK-11. The polar lipid profile contained disphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylinositol and two unknown glycolipids. DNA of the type strain had a G+C content of 67.4 mol%. On the basis of the phylogenetic properties and phenotypic distinctiveness, TS-56(T) represents a novel species of the genus Gryllotalpicola, for which the name Gryllotalpicola reticulitermitis sp. nov. is proposed. The type strain is TS-56(T) (?=?CGMCC 1.10363(T)?=?NBRC 109838(T)). PMID:25281726

Fang, Hao; Lv, Wanyu; Huang, Zhou; Liu, Shuang-Jiang; Yang, Hong

2015-01-01

319

Performance of a new thermostable mannanase in breaking guar-based fracturing fluids at high temperatures with little premature degradation.  

PubMed

A new thermostable ?-1,4-mannanase (DtManB) cloned from Dictyoglomus thermophilum CGMCC 7283 showed the maximum activity towards hydroxypropyl guar gum at 80 C, with a half-life of 46 h. DtManB exhibited good compatibility with various additives of fracturing fluid, retaining more than 50 % activity in all the cases tested. More importantly, premature degradation could be alleviated significantly when using DtManB as breaker, because at 27 and 50 C it displayed merely 3.7 and 18.5 % activities compared to those at 80 C. In a static test, 0.48 mg DtManB could break 200 mL borax cross-linked fracturing fluid dramatically at 80 C, and merely 18 mPa s of the viscosity was detected even after the broken fluid was cooled down and only 161.4 mg L(-1) of the residue was left after the enzymatic reaction. All these positive features demonstrate the great potential of this mannanase as a new enzyme breaker for application in enhanced recovery of petroleum oil. PMID:24150905

Hu, Ke; Li, Chun-Xiu; Pan, Jiang; Ni, Yan; Zhang, Xiao-Yan; Xu, Jian-He

2014-02-01

320

Virgibacillus chiguensis sp. nov., a novel halophilic bacterium isolated from Chigu, a previously commercial saltern located in southern Taiwan.  

PubMed

A Gram-positive, motile, endospore-forming, irregular rod-shaped (0.7-0.9 x 2.5-5.0 microm), halophilic bacterial strain, NTU-101(T), was isolated from Chigu saltern in southern Taiwan, previously used as a salt production field. The isolate was characterized taxonomically based on biochemical and molecular approaches. It grows optimally at 40 degrees C and in the presence of 5-10 % NaCl. Strain NTU-101(T) has cell-wall peptidoglycan based on meso-diaminopimelic acid and MK-7 as the predominant menaquinone. Major polar lipids are phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. Anteiso-C(15 : 0), iso-C(15 : 0) and anteiso-C(17 : 0) are the major fatty acids. The DNA G+C content was 37.3 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed its affiliation to the genus Virgibacillus. DNA-DNA relatedness values between strain NTU-101(T) and Virgibacillus dokdonensis and Virgibacillus pantothenticus were 17.5 and 21.5 %, respectively. Based on the phenotypic and phylogenetic properties, strain NTU-101(T) (=BCRC 17637(T)=CGMCC 1.6496(T)) was classified as a novel strain of Virgibacillus species, for which the name Virgibacillus chiguensis sp. nov. is proposed. PMID:18218928

Wang, Chung-Yi; Chang, Chen-Chin; Ng, Chang Chai; Chen, Tseng-Wei; Shyu, Yuan-Tay

2008-02-01

321

Methanospirillum psychrodurum sp. nov., isolated from wetland soil.  

PubMed

A psychrotolerant methanogenic strain, X-18(T), was isolated from the soil of the Madoi wetland at Qinghai, Tibetan plateau, China. Cells were wavy rods (11-62 m long) with blunt tapered ends and Gram-stain-negative. Strain X-18(T) grew strictly anaerobically and produced methane exclusively from H2/CO2. Growth occurred in the temperature range of 4-32 C and optimally at 25 C. Growth pH ranged from 6.5 to 8.0 and the optimum was 7.0. The G+C content of the genomic DNA of strain X-18(T) was 44.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences and the alpha subunit of methyl-coenzyme M reductase indicated that strain X-18(T) was affiliated to the genus Methanospirillum and was most closely related to Methanospirillum lacunae Ki8-1(T), with 96.3% 16S rRNA gene sequence similarity. However, strain X-18(T) could be distinguished from the existing species of the genus Methanospirillum by its lower growth temperature and obligate hydrogenotrophic methanogenesis. On the basis of phenotypic characteristics and phylogenetic analysis, strain X-18(T) represents a novel species of the genus Methanospirillum, for which the name Methanospirillum psychrodurum sp. nov. is proposed and strain X-18(T) is assigned as the type strain (?=?CGMCC 1.5186(T)?=?JCM 19216(T)). PMID:24158951

Zhou, Liguang; Liu, Xiaoli; Dong, Xiuzhu

2014-02-01

322

Mycetocola miduiensis sp. nov., a psychrotolerant bacterium isolated from Midui glacier.  

PubMed

An aerobic, asporous, flagellated, Gram-stain-positive, rod-shaped bacterium MD-T1-10-2(T) was isolated from the topsoil of Midui Glacier, Tibet Province, China. Phylogenetic analysis based on 16S rRNA gene sequence analysis placed the strain in a clade containing Mycetocola manganoxydans CCTCC AB 209002(T), Mycetocola reblochoni DSM 18580(T), Mycetocola tolaasinivorans JCM 11656(T), Mycetocola lacteus JCM 11654(T) and Mycetocola saprophilus JCM 11655(T), with the sequence similarities of 99.2, 98.1, 96.7, 96.6 and 96.4 %, respectively. DNA-DNA hybridization analysis indicated that strain MD-T1-10-2(T) represented a new member of this genus. The optimal ranges of temperature and pH for growth were 20-25 C and 7.0-9.0, respectively; the strain could even grow at 0 C. The major cellular fatty acids were anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The predominant menaquinones were MK-10 and MK-11. The cell wall amino acids were lysine, alanine, glycine and glutamic acids. The DNA G+C content was 65.9 mol%. Based on the genotypic and phenotypic data, strain MD-T1-10-2(T) for which the name Mycetocola miduiensis sp. nov. is proposed; the type strain is MD-T1-10-2(T) ( = CGMCC 1.11101(T) = NBRC 107877(T)). PMID:23291895

Zhu, Lang; Liu, Qing; Liu, Hongcan; Zhou, Yuguang; Xin, Yuhua; Dong, Xiuzhu

2013-07-01

323

Flavobacterium noncentrifugens sp. nov., a psychrotolerant bacterium isolated from glacier meltwater.  

PubMed

A non-motile, Gram-stain-negative bacterium, designated R-HLS-17(T), was isolated from the meltwater of Hailuogou Glacier located in Sichuan province, south-west China. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belonged to the genus Flavobacterium, with the closest relatives being Flavobacterium antarcticum JCM 12383(T) (95.5% 16S rRNA gene sequence similarity), F. omnivorum JCM 11313(T) (95.0%) and F. fryxellicola LMG 22022(T) (95.2%). Growth occurred at 0-29 C (optimum, 10-20 C) and pH 6.0-8.5 (optimum, 7.0-8.0). The DNA G+C content was 46.5 mol%. The major cellular fatty acids were iso-C15:0, iso-C15:1 G, summed feature 9 (comprising iso-C17:1?9c and/or 10-methyl C16:0), iso-C17:0 3-OH and iso-C15:0 3-OH. The predominant menaquinone was MK-6. Based on the genotypic and phenotypic characteristics, we propose that strain R-HLS-17(T) represents a novel species of the genus Flavobacterium, Flavobacterium noncentrifugens sp. nov. The type strain is R-HLS-17(T) (=CGMCC 1.10076(T)=NBRC 108844(T)). PMID:23064352

Zhu, Lang; Liu, Qing; Liu, Hongcan; Zhang, Jianli; Dong, Xiuzhu; Zhou, Yuguang; Xin, Yuhua

2013-06-01

324

Fulvimarina manganoxydans sp. nov., isolated from a deep-sea hydrothermal plume in the south-west Indian Ocean.  

PubMed

An aerobic, Mn(II)-oxidizing, Gram-negative bacterium, strain 8047(T), was isolated from a deep-sea hydrothermal vent plume in the south-west Indian Ocean. The strain was rod-shaped and motile with a terminal flagellum, and formed yellowish colonies. It produced catalase and oxidase, hydrolysed gelatin and reduced nitrate. 16S rRNA gene sequence analysis showed that strain 8047(T) belonged to the order Rhizobiales of the class Alphaproteobacteria, and was phylogenetically most closely related to the genus Fulvimarina, sharing 94.4% sequence identity with the type strain of the type species. The taxonomic affiliation of strain 8047(T) was supported by phylogenetic analysis of four additional housekeeping genes, gyrB, recA, rpoC and rpoB. The predominant respiratory lipoquinone of strain 8047(T) was Q-10, the major fatty acid was C(18?:?1)?7c and the DNA G+C content was 61.7 mol%. On the basis of the phenotypic and genotypic characteristics determined in this study, strain 8047(T) represents a novel species within the genus Fulvimarina, for which the name Fulvimarina manganoxydans sp. nov. is proposed. The type strain is strain 8047(T) (?=?CGMCC1.10972(T)?=?JCM 18890(T)). PMID:24854008

Ren, Fei; Zhang, Limin; Song, Lei; Xu, Shiyao; Xi, Lijun; Huang, Li; Huang, Ying; Dai, Xin

2014-08-01

325

Janibacter indicus sp. nov., isolated from hydrothermal sediment of the Indian Ocean.  

PubMed

A Gram-staining-positive, aerobic and non-motile strain, 0704P10-1(T), was isolated from hydrothermal sediment of the Indian Ocean. Phylogenetic, phenotypic and chemotaxonomic data for the organism supported that it belonged to the genus Janibacter. Strain 0704P10-1(T) showed 97.2-98.7% 16S rRNA gene sequence similarities to the type strains of recognized members of the genus Janibacter. It contained meso-diaminopimelic acid as the diagnostic diamino acid in the cell wall. MK-8(H4) was the only menaquinone detected. The major fatty acids were iso-C16 : 0, C17 : 1?8c and 10-methyl C17 : 0. Meanwhile, the results of DNA-DNA hybridization studies and other physiological and biochemical tests allowed the genotypic and phenotypic differentiation of strain 0704P10-1(T) from closely related species. Thus, strain 0704P10-1(T) represents a novel species of the genus Janibacter, for which the name Janibacter indicus sp. nov. is proposed. The type strain is 0704P10-1(T) (?= LMG 27493(T)?= CGMCC 1.12511(T)). PMID:24744020

Zhang, Gaiyun; Ren, Huihui; Wang, Shuang; Chen, Xiu; Yang, Yanliu; Zhang, Yubian; Jiang, Yi

2014-07-01

326

Moheibacter sediminis gen. nov., sp. nov., a member of the family Flavobacteriaceae isolated from sediment, and emended descriptions of Empedobacter brevis, Wautersiella falsenii and Weeksella virosa.  

PubMed

A Gram-reaction-negative, yellow-pigmented, strictly aerobic bacterium, designated M0116T, was isolated from the sediment of the Mohe Basin in north-east China. Flexirubin-type pigments were produced. Cells were catalase- and oxidase-positive and non-gliding rods. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain M0116T was a member of the family Flavobacteriaceae and was most closely related to members of the genera Empedobacter, Wautersiella and Weeksella with 90.5-91.0% sequence similarities. The major cellular fatty acids were iso-C15:0 and iso-C17:0 3-OH. The major respiratory quinone was MK-6 and the major polar lipid was phosphatidylethanolamine. The DNA G+C content was 38.2 mol%. Based on phenotypic, phylogenetic and genotypic data, strain M0116T is considered to represent a novel species of a new genus in the family Flavobacteriaceae, for which the name Moheibacter sediminis gen. nov., sp. nov. is proposed. The type strain is M0116T (=CGMCC 1.12708T=JCM 19634T). Emended descriptions of Empedobacter brevis, Wautersiella falsenii and Weeksella virosa are also proposed. PMID:24453231

Zhang, Ren-Gang; Tan, Xu; Zhao, Xing-Min; Deng, Jian; Lv, Jie

2014-05-01

327

Enhanced deacidification activity in Schizosaccharomyces pombe by genome shuffling.  

PubMed

A problem frequently occurring in making some kinds of wines, particularly Vitis quinquangularis Rehd wine, is the presence of malic acid at high concentrations, which is detrimental to the quality of wines. Thus, there is a need of the ways for effectively reducing the malic acid levels in wine. This study aimed to generate shuffled fusants of Schizosaccharomyces pombe with enhanced deacidification activity for reducing the excessive malic acid content in wine. Sz. pombe CGMCC 2.1628 was used as the original strain. The starting mutant population was generated by UV treatment. The mutants with higher deacidification activity were selected and subjected to recursive protoplast fusion. The resulting fusants were screened by using the indicator of malic acid concentration of fermentation supernatants on 96-well microtitre plates, measured with bromocresol green. After three rounds of genome shuffling, the best-performing fusant, named GS3-1, was obtained. Its deacidification activity (consumed 4.78?g/l malic acid within 10?days) was increased by 225.2% as compared to that of original strain. In the Vitis quinquangularis Rehd wine fermentation test, GS3-1 consumed 4.0?g/l malic acid during the whole cycle of fermentation, providing up to 185.7% improvement in malic acid consumption compared with that of the original strain. This study shows that GS3-1 has great potential for improving the quality of Vitis quinquangularis Rehd wine. PMID:25377082

Ding, Su; Zhang, Ying; Zhang, Jing; Zeng, Wei; Yang, Ying; Guan, Jingxi; Pan, Lixia; Li, Wei

2015-02-01

328

Nonomuraea solani sp. nov., an actinomycete isolated from eggplant root (Solanum melongena L.).  

PubMed

A novel actinomycete, designated strain NEAU-Z6(T), was isolated from eggplant (Solanum melongena L.) root. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain NEAU-Z6(T) belonged to the genus Nonomuraea, with highest sequence similarity to Nonomuraea monospora PT 708(T) (98.83 %), Nonomuraea rosea GW 12687(T) (98.55 %) and Nonomuraea rhizophila YIM 67092(T) (98.02 %). Sequence similarities between strain NEAU-Z6(T) and other species of the genus Nonomuraea ranged from 97.94 % (Nonomuraea candida HMC10(T)) to 96.30 % (Nonomuraea wenchangensis 210417(T)). Key morphological, physiological and chemotaxonomic characteristics of strain NEAU-Z6(T) were congruent with the description of the genus Nonomuraea. The G+C content of the genomic DNA was 64.51 mol%. DNA-DNA relatedness and comparative analysis of physiological, biochemical and chemotaxonomic data allowed genotypic and phenotypic differentiation of strain NEAU-Z6(T) from closely related species. Thus, strain NEAU-Z6(T) represents a novel species of the genus Nonomuraea, for which the name Nonomuraea solani sp. nov. is proposed. The type strain is NEAU-Z6(T) ( = CGMCC 4.7037(T) = DSM 45729(T)). PMID:23203622

Wang, Xiangjing; Zhao, Junwei; Liu, Chongxi; Wang, Jidong; Shen, Yue; Jia, Feiyu; Wang, Liang; Zhang, Ji; Yu, Chao; Xiang, Wensheng

2013-07-01

329

Microbial community structure of ethanol type fermentation in bio-hydrogen production.  

PubMed

Three continuous stirred-tank reactors (CSTRs) were used for H(2) production from molasses wastewater at influent pH of 6.0-6.5 (reactor A), 5.5-6.0 (reactor B), or 4.0-4.5 (reactor C). After operation for 28 days, the microbial community formed ethanol type (C), propionate type (A) and ethanol-butyrate-mixed type (B) fermentation. The H(2) production rate was the highest for ethanol type fermentation, 0.40 l (g VSS)(-1) day(-1) or 0.45 l H(2) (g COD removed)(-1). Microbial community dynamics and diversity were analysed using double-gradient denaturing gradient gel electrophoresis (DG-DGGE). Denaturing gradient gel electrophoresis profiles indicated that the community structures changed quickly in the first 14 days. Phylogenetic analysis indicated that the dominant bacterial groups were low G+C Gram-positive bacteria, Bacteroides, gamma-Proteobacteria and Actinobacteria; alpha-Proteobacteria, beta-Proteobacteria, delta-Proteobacteria and Spirochaetes were also presented as minor groups in the three reactors. H(2)-producing bacteria were affiliated with Ethanoligenens, Acetanaerobacterium, Clostridium, Megasphaera, Citrobacter and Bacteroides. An ethanol-based H(2)-producing bacterium, Ethanoligenens harbinense CGMCC1152, was isolated from reactor C and visualized using fluorescence in situ hybridization (FISH) to be 19% of the eubacteria in reactor C. In addition, isoenzyme activity staining for alcohol dehydrogenase (ADH) supported that the majority of ethanol-producing bacteria were affiliated with Ethanoligenens in the microbial community. PMID:17472628

Ren, Nanqi; Xing, Defeng; Rittmann, Bruce E; Zhao, Lihua; Xie, Tianhui; Zhao, Xin

2007-05-01

330

Oceanobacillus luteolus sp. nov., isolated from soil.  

PubMed

Two Gram-stain-positive, rod-shaped and endospore-forming bacteria, designated WM-1T and WM-4, were isolated from a paddy soil and a forest soil, respectively, in South China. Comparative 16S rRNA gene sequence analyses showed that both strains were members of the genus Oceanobacillus and most closely related to Oceanobacillus chironomi LMG 23627T with pairwise sequence similarity of 96.0%. The isolates contained menaquinone-7 (MK-7) as the respiratory quinone and anteiso-C15:0, anteiso-C17:0 and iso-C15:0 as the major fatty acids (>10%). Polar lipids consisted of a predominance of diphosphatidylglycerol and moderate to minor amounts of phosphatidylglycerol and phosphatidylinositol. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The DNA G+C content was 38.6-39.2 mol%. The 16S rRNA gene sequence of strain WM-1T displayed 99.7?% similarity to that of strain WM-4, and DNA-DNA hybridization between the two strains showed a relatedness value of 91?%. Based on the results of this polyphasic study, strains WM-1T and WM-4 represent a novel species in the genus Oceanobacillus, for which the name Oceanobacillus luteolus sp. nov. is proposed. The type strain is WM-1T (=KCTC 33119T=CGMCC 1.12406T). PMID:24453233

Wu, Min; Yang, Guiqin; Yu, Zhen; Zhuang, Li; Jin, Yingqiang; Zhou, Shungui

2014-05-01

331

Paenibacillus shenyangensis sp. nov., a bioflocculant-producing species isolated from soil under a peach tree.  

PubMed

A Gram-stain-positive, aerobic or facultatively anaerobic, rod-shaped, non-motile, endospore-forming bacterium, strain A9(T), was isolated in 1996 from a soil sample collected under a peach tree in Qingnian Park in Shenyang, PR China, and its taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strain belonged to the genus Paenibacillus, and was most closely related to the type strain of Paenibacillus hunanensis with a 16S rRNA gene sequence similarity of 96.7?% and a DNA-DNA relatedness value of 51.6?%. The major polar lipids of strain A9(T) were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant menaquinone was MK-7 and the major cellular fatty acids were anteiso-C15?:?0, C16?:?0 and iso-C15?:?0. The DNA G+C content was 51.9 mol%. Based on these results, it is concluded that strain A9(T) represents a novel species of the genus Paenibacillus, for which the name Paenibacillus shenyangensis sp. nov. is proposed, with A9(T) (?=?JCM 19307(T)?=?CGMCC 2040(T)) as the type strain. PMID:25323595

Jiang, Binhui; Zhao, Xin; Liu, Jinliang; Fu, Lili; Yang, Chengcheng; Hu, Xiaomin

2015-01-01

332

Biotransformation of 1,3-propanediol cyclic sulfate and its derivatives to diols by Rhodococcus sp.  

PubMed

Rhodococcus sp. CGMCC 4911 transformed 1,3-propanediol cyclic sulfate (1,3-PDS) and its derivatives into corresponding diols. Ethylene sulfate, glycol sulfide, 1,3-PDS, and 1,2-propanediol cyclic sulfate were effectively hydrolyzed with growing cells. (R)-1,2-Propanediol (>99 % e.e.) was obtained at 44 % yield with growing cells. Glycol sulfide, ethylene sulfate, and 1,3-PDS were converted into the corresponding diols at 94.6, 96.3, and 98.3 %, respectively. Optimal reaction conditions with lyophilized resting cells were 30 C, pH 7.5, and cell dosage 17.9 mg cell dry wt/ml. 1,3-Propanediol was obtained from 50 mM 1,3-PDS at 97.2 % yield by lyophilized cells after 16 h. Lyophilized cells were entrapped in calcium alginate with a half-life of 263 h at 30 C, and the total operational time of the immobilized biocatalysts could reach over 192 h with a high conversion rate. PMID:25214230

He, Yu-Cai; Tao, Zhi-Cheng; Zhang, Dan-Ping; Yang, Zhen-Xing; Gao, Shan; Ma, Cui-Luan

2015-01-01

333

Identification of novel eubacteria from spent mushroom compost (SMC) waste by DNA sequence typing: ecological considerations of disposal on agricultural land.  

PubMed

A small study was undertaken to examine the microbiological characteristics of spent mushroom compost (SMC), which is the major waste by-product of the mushroom industry and which is regularly disposed off by application to agricultural land. The primary aim of this study was to examine SMC for the presence of faecal bacterial pathogens, including Campylobacter spp., Salmonella spp. and Listeria monocytogenes. Secondly it was desirable to quantify bacterial and fungal populations within SMC, and also qualitatively identify the diversity of bacterial populations within SMC, through employment of rDNA PCR and direct sequencing techniques on the culturable microflora. Conventional microbiological analyses of SMC material (n=30) from six commercial operations in both Northern Ireland and the Republic of Ireland, failed to detect Salmonella spp, Listeria spp. or Campylobacter spp. in any of the SMC material examined. Total aerobic plate counts gave a mean count of log10 7.01 colony forming units (cfu) per gram SMC material (range: log10 6.53-7.52 cfu/g). Fungal counts gave a mean count of log(10) 4.57 cfu per gram SMC material (range: log10 3.93-4.98 cfu/g). From a total of greater than 50 colony picks, a total of 12 bacterial morphotypes were identified and were further examined by employment of partial 16S rRNA gene amplification and sequencing techniques, yielding several genera and species, including Bacillus licheniformis, Bacillus subtilis, Klebsiella/Enterobacter sp. Microbacterium sp. Paenibacillus lentimorbus, Pseudomonas mevalonii, Sphingobacterium multivorum and Stenotrophomonas sp. This is the first preliminary report on the microbial diversity of SMC waste and demonstrates the presence of several species that have not been previously described in SMC, in addition to two potentially novel species within the genera Microbacterium and Stenotrophomonas. It is thereby important to examine the ecological microbe-microbe and plant-microbe interactions that are occurring between the native bacterial soil flora and those added annually (theoretically estimated at approximately 10(18) cells) through the application of SMC. Such studies would be beneficial in helping to ascertain the ecological consequences involved in the disposal of SMC waste on agricultural land. PMID:14672727

Watabe, M; Rao, J R; Xu, J; Millar, B C; Ward, R F; Moore, J E

2004-01-01

334

Halorubrum rubrum sp. nov., an extremely halophilic archaeon from a Chinese salt lake.  

PubMed

Two halophilic archaeal strains, YC87(T) and YCA11, were isolated from Yuncheng salt lake in Shanxi, China. Cells of the two strains were observed to be pleomorphic rod-shaped, stained Gram-negative and produced red-pigmented colonies. Strain YC87(T) was able to grow at 20-50C (optimum 37C), at 1.4-4.8M NaCl (optimum 2.1M NaCl), at 0.05-1.0M MgCl2 (optimum 0.3M MgCl2) and at pH 6.0-9.0 (optimum pH 7.0) while strain YCA11 was able to grow at 20-50C (optimum 37C), at 2.1-4.8M NaCl (optimum 3.1M NaCl), at 0.01-0.7M MgCl2 (optimum 0.1M MgCl2) and at pH 6.0-9.0 (optimum pH 7.5). The cells of both isolates were observed to lyse in distilled water. The minimum NaCl concentrations that prevented cell lysis were determined to be 8% (w/v) for strain YC87(T) and 12% (w/v) for strain YCA11. The major polar lipids of the two strains were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and one major glycolipid chromatographically identical to sulfated mannosyl glucosyl diether; another major glycolipid and trace amounts of several unidentified lipids were also detected. The 16S rRNA gene sequences of the two strains were 99.8% identical, showing 93.2-98.2% similarity to members of the genus Halorubrum of the family Halobacteriaceae. The rpoB' gene similarity between strains YC87(T) and YCA11 was 99.3% and showed 87.5-95.2% similarity to the closest relative members of the genus Halorubrum. The DNA G+C content of strains YC87(T) and YCA11 were determined to be 64.9 and 64.5mol%, respectively. The DNA-DNA hybridization value between strain YC20(T) and strain YC77 was 87% and the two strains showed low DNA-DNA relatedness with Halorubrum cibi JCM 15757(T) and Halorubrum aquaticum CGMCC 1.6377(T), the most related members of the genus Halorubrum. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains YC87(T) and YCA11 represent a novel species of the genus Halorubrum, for which the name Halorubrum rubrum sp. nov. is proposed. The type strain is YC87(T) (=CGMCC 1.12124(T)=JCM 18365(T)). PMID:23949820

Qiu, Xing-Xing; Zhao, Mei-Lin; Han, Dong; Zhang, Wen-Jiao; Cui, Heng-Lin

2013-11-01

335

Halobellus clavatus gen. nov., sp. nov. and Halorientalis regularis gen. nov., sp. nov., two new members of the family Halobacteriaceae.  

PubMed

Four halophilic archaeal strains, designated TNN18(T), TBN12, TNN28(T) and TBN19, were isolated from brines sampled from two artificial marine solar salterns in eastern China. Strains TNN18(T) and TNN28(T) were isolated from the Tainan marine solar saltern, whereas strains TBN12 and TBN19 were from the Taibei marine solar saltern. Colonies of the four strains were red-pigmented and their cells were pleomorphic, motile, Gram-reaction-negative rods. Strains TNN18(T) and TBN12 were able to grow at 25-50 C (optimum 37 C), in 10-3 ?% (w/v) NaCl (optimum 15 %), with 0-1.0 M MgCl(2) (optimum 0.05 M) and at pH 5.5-9.0 (optimum pH 7.0-7.5), while strains TNN28(T) and TBN19 were able to grow at 20-50 C (optimum 37 C), in 15-30 % (w/v) NaCl (optimum 18-20 %), in 0.005-1.0 M MgCl(2) (optimum 0.01-0.3 M) and at pH 6.0-9.0 (optimum pH 7.0-7.5). Cells of these strains lyse in distilled water; minimal NaCl concentrations to prevent cell-lysis are 10?% (w/v) for strains TNN18(T) and TBN12 and 12 % (w/v) for strains TNN28(T) and TBN19. The major polar lipids of strains TNN18(T) and TBN12 were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS) and one major glycolipid (GL1), which was chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1). Minor amounts of other lipids (GL0, GL2, GL3 and GL4) were also detectable. The polar lipid profiles of strains TNN28(T) and TBN19 contained PG, PGP-Me, GL1, which was chromatographically identical to S-DGD-1, and three to four minor unidentified glycolipids (GL2-GL5). Phylogenetic analyses revealed that strains TNN18(T) and TBN12 formed a distinct clade with strains of the closest related species, Haloquadratum walsbyi (91.5-91.8 % 16S rRNA gene sequence similarity) and strains TNN28(T) and TBN19 formed a distinct clade with strains of the species Halosimplex carlsbadense (89.9-93.3 % similarity) and two members of the genus Halorhabdus (92.5-93.3 % similarity). The DNA G+C contents of strains TNN18(T), TBN12, TNN28(T) and TBN19 were 61.5, 62.4, 61.9 and 61.5 mol%, respectively. DNA-DNA hybridization values between strains TNN18(T) and TBN12, and strains TNN28(T) and TBN19 were 82.9 % and 88.2 %, respectively. The phenotypic, chemotaxonomic and phylogenetic properties suggest that the four strains represent two novel species of two new genera within the family Halobacteriaceae, for which the names Halobellus clavatus gen. nov., sp. nov. (type strain TNN18(T ) = CGMCC 1.10118(T ) = JCM 16424(T)) and Halorientalis regularis gen. nov., sp. nov. (type strain TNN28(T ) = CGMCC 1.10123(T ) = JCM 16425(T)) are proposed. PMID:21169458

Cui, Heng-Lin; Yang, Xin; Gao, Xia; Xu, Xue-Wei

2011-11-01

336

Halobellus limi sp. nov. and Halobellus salinus sp. nov., isolated from two marine solar salterns.  

PubMed

Two halophilic archaea, strains TBN53(T) and CSW2.24.4(T), were characterized to elucidate their taxonomic status. Strain TBN53(T) was isolated from the Taibei marine solar saltern near Lianyungang city, Jiangsu province, China, whereas strain CSW2.24.4(T) was isolated from a saltern crystallizer in Victoria, Australia. Cells of the two strains were pleomorphic, stained Gram-negative and produced red-pigmented colonies. Strain TBN53(T) was able to grow at 25-55 C (optimum 45 C), with 1.4-5.1 M NaCl (optimum 2.6-3.9 M NaCl), with 0-1.0 M MgCl(2) (optimum 0-0.1 M MgCl(2)) and at pH 5.5-9.5 (optimum pH 7.0), whereas strain CSW2.24.4(T) was able to grow at 25-45 C (optimum 37 C), with 2.6-5.1 M NaCl (optimum 3.4 M NaCl), with 0.01-0.7 M MgCl(2) (optimum 0.05 M MgCl(2)) and at pH 5.5-9.5 (optimum pH 7.0-7.5). Cells of the two isolates lysed in distilled water. The minimum NaCl concentrations that prevented cell lysis were 8 % (w/v) for strain TBN53(T) and 12 % (w/v) for strain CSW2.24.4(T). The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate, with two glycolipids chromatographically identical to sulfated mannosyl glucosyl diether and mannosyl glucosyl diether, respectively. Trace amounts of other unidentified lipids were also detected. On the basis of 16S rRNA gene sequence analysis, strains TBN53(T) and CSW2.24.4(T) showed 94.1 % similarity to each other and were closely related to Halobellus clavatus TNN18(T) (95.0 and 94.7 % similarity, respectively). Levels of rpoB' gene sequence similarity between strains TBN53(T) and CSW2.24.4(T), and between these strains and Halobellus clavatus TNN18(T) were 88.5, 88.5 and 88.1 %, respectively. The DNA G+C contents of strains TBN53(T) and CSW2.24.4(T) were 69.2 and 67.0 mol%, respectively. The level of DNA-DNA relatedness between strain TBN53(T) and strain CSW2.24.4(T) was 25 %, and these two strains showed low levels of DNA-DNA relatedness with Halobellus clavatus TNN18(T) (30 and 29 % relatedness, respectively). Based on these phenotypic, chemotaxonomic and phylogenetic properties, two novel species of the genus Halobellus are proposed to accommodate these two strains, Halobellus limi sp. nov. (type strain TBN53(T) = CGMCC 1.10331(T) = JCM 16811(T)) and Halobellus salinus sp. nov. (type strain CSW2.24.4(T) = DSM 18730(T) = CGMCC 1.10710(T) = JCM 14359(T)). PMID:22661071

Cui, Heng-Lin; Yang, Xin; Zhou, Yu-Guang; Liu, Hong-Can; Zhou, Pei-Jin; Dyall-Smith, Mike L

2012-06-01

337

Plastorhodobacter daqingensis gen. nov., sp. nov.: A Non-phototrophic Bacterium Isolated from Daqing Oilfield.  

PubMed

Two aerobic Gram staining negative, non-motile, and rod-shaped strains, DQW12E81-30(T) and DQW12E6-37-1, were isolated from an oil production mixture from Daqing Oilfield, northeastern China. Phylogenetic analysis based on the nearly complete 16S rRNA gene sequences revealed that strains DQW12E81-30(T) and DQW12E6-37-1 were members of family Rhodobacteraceae, which showed 95.6-95.9% of 16S rRNA gene sequence similarities with Pararhodobacter aggregans DSM 18938(T), Rhodobacter veldkampii CGMCC 1.5006(T), and Roseinatronobacter thiooxidans DSM 13087(T), and lower similarities (<95.1%) with all the left type species. Growth of strains DQW12E81-30(T) and DQW12E6-37-1 occurred at pH 7-8, 15-45C, and 0-4% (w/v) of NaCl. The strains could grow both in dark and in light, but neither photosynthetic pigments nor photosynthetic reaction center gene pufM were detected in the strains. These photosynthesis-related features of the two isolates were different from those of Rhodobacter and Roseinatronobacter bacteria, but similar with those of Pararhodobacter. The genomic DNA G+C contents of strains DQW12E81-30(T) and DQW12E6-37-1 were 66.9 and 63.7mol%, respectively. The predominant ubiquinone was Q-10 for both the strains. The major polar lipids of strain DQW12E81-30(T) were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, unidentified aminolipid, unidentified glycolipid, and unidentified phospholipid. The two strains had C18:1 ?7c, C18:0, and C18:1 ?7c 11-methyl as the major fatty acids. In addition, the strains DQW12E81-30(T) and DQW12E6-37-1 had C16:1 ?7c/C16:1 ?6c, C12:0, C14:0, C14:0 3-OH/C16:1 iso I, C10:0 3-OH, which were remarkably different from those of Pararhodobacter and Roseinatronobacter. The results of phenotypic, genotypic, and chemotaxonomic characteristics analyses indicated that strains DQW12E81-30(T) and DQW12E6-37-1 were readily different from their most phylogenetically closely related genera. Plastorhodobacter daqingensis gen. nov, sp. nov. is proposed for strains DQW12E81-30(T) and DQW12E6-37-1. The type strain is DQW12E81-30(T) (=LMG 27732(T)=CGMCC 1.12750(T)). PMID:25572494

Xie, Bai-Sheng; Lv, Xiang-Lin; Cai, Man; Tang, Yue-Qin; Wang, Ya-Nan; Cui, Heng-Lin; Liu, Xue-Ying; Tan, Yan; Wu, Xiao-Lei

2015-05-01

338

"Chemical nose" for the visual identification of emerging ocular pathogens using gold nanostars.  

PubMed

Ocular pathogens can cause serious damages in the eye leading to severe vision loss and even blindness if left untreated. Identification of pathogens is crucial for administering the appropriate antibiotics in order to gain effective control over ocular infection. Herein, we report a gold nanostar based "chemical nose" for visually identifying ocular pathogens. Using a spectrophotometer and nanostars of different sizes and degrees of branching, we show that the "chemical nose" is capable of identifying the following clinically relevant ocular pathogens with an accuracy of 99%: S. aureus, A. xylosoxidans, D. acidovorans and S. maltophilia. The differential colorimetric response is due to electrostatic aggregation of cationic gold nanostars around bacteria without the use of biomolecule ligands such as aptamers or antibodies. Transmission electron microscopy confirms that the number of gold nanostars aggregated around each bacterium correlates closely with the colorimetric response. Thus, gold nanostars serve as a promising platform for rapid visual identification of ocular pathogens with application in point-of-care diagnostics. PMID:24912040

Verma, Mohit S; Chen, Paul Z; Jones, Lyndon; Gu, Frank X

2014-11-15

339

Bacterial arthritis.  

PubMed

In this review of the 1990 septic arthritis literature, we revisit synovial fluid leukocytosis, examine the utility of synovial fluid glucose and protein measurements, and look at the levels of two cytokines, tumor necrosis factor and interleukin-1, in infected joint fluids. We see the many faces of gonococcal arthritis and the ravages of septic arthritis when the host has rheumatoid arthritis. Should we recommend antibiotic prophylaxis for the rheumatoid patient with a prosthetic joint who is undergoing a procedure that leads to transient bacteremia? What are some of the salient features of septic arthritis when it involves the sternoclavicular or sacroiliac joints? We also look at some unusual microorganisms, eg, group C Streptococcus, Streptococcus viridans, Listeria monocytogenes, Pseudomonas cepacia, Pseudomonas maltophilia, and Neisseria sicca. In patients with acquired immunodeficiency syndrome, we encounter reports of septic arthritis, osteomyelitis, and spinal epidural abscess caused by opportunistic microorganisms. Two unusual sites of infection include the C1-2 lateral facet joint and subacromial bursa without involvement of the glenohumeral joint. Finally, we examine how to drain a septic knee: the orthopedic point of view. PMID:1911055

Ho, G

1991-08-01

340

Isolation and characterization of aerobic culturable arsenic-resistant bacteria from surfacewater and groundwater of Rautahat District, Nepal.  

PubMed

Arsenic (As) contamination of groundwater is a serious Environmental Health Management issue of drinking water sources especially in Terai region of Nepal. Many studies have reported that due to natural abundance of arsenic in the environment, various bacteria have developed different resistance mechanisms for arsenic compound. In this study, the culturable arsenic-resistant bacteria indigenous to surfacewater as well as groundwater from Rautahat District of Nepal were randomly isolated by standard plate count method on the basis of viable growth on plate count agar amended with arsenate ranging from 0, 0.5, 10, 40, 80 to 160 milligram per liter (mg/l). With respect to the morphological and biochemical tests, nine morphologically distinct potent arsenate tolerant bacteria showed relatedness with Micrococcus varians, Micrococcus roseus, Micrococcus luteus, Pseudomonas maltophilia, Pseudomonas sp., Vibrio parahaemolyticus, Bacillus cereus, Bacillus smithii 1 and Bacillus smithii 2. The isolates were capable of tolerating more than 1000 mg/l of arsenate and 749 mg/l of arsenite. Likewise, bioaccumulation capability was highest with M. roseus (85.61%) and the least with B. smithii (47.88%) indicating the potential of the organisms in arsenic resistance and most probably in bioremediation. PMID:21868146

Shakya, S; Pradhan, B; Smith, L; Shrestha, J; Tuladhar, S

2012-03-01

341

60Co-irradiation as an alternate method for sterilization of penicillin G, neomycin, novobiocin, and dihydrostreptomycin  

SciTech Connect

The effects of the use of 60Co-irradiation to sterilize antibiotics were evaluated. The antibiotic powders were only occasionally contaminated with microorganisms. The D-values of the products and environmental isolates were 0.028, 0.027, 0.015, 0.046, 0.15, 0.018, and 0.19 Mrads for Aspergillus species (UC 7297, 7298), A. fumigatus (UC 7299), Rhodotorula species (UC 7300), Penicillium oxalicum (UC 7269), Pseudomonas maltophilia (UC 6855), and a biological indicator microorganism, Bacillus pumilus spores (ATCC 27142). An irradiation dose of 1.14 Mrads, therefore, was sufficient to achieve a six-log cycle destruction of B. pumilus spores. Based on the bioburden data, a minimum irradiation dose of 1.05 Mrads was calculated to be sufficient to obtain a 10(-6) probability of sterilizing the most radioresistant isolate, Pen. oxalicum. To determine the radiolytic degradation scheme and the stability of the antibiotics following irradiation, high-performance liquid chromatographic (HPLC) methods were developed. The resulting rates of degradation for the antibiotics were 0.6, 1.2, 2.3, and 0.95%/Mrad for penicillin G, neomycin, novobiocin, and dihydrostreptomycin, respectively. Furthermore, radiolytic degradation pathways for the antibiotics were identified and found to be similar to those commonly encountered when antibiotics are subjected to acidic, basic, hydrolytic, or oxidative treatments. No radiolytic compounds unique to 60Co-irradiation were found.

Tsuji, K.; Rahn, P.D.; Steindler, K.A.

1983-01-01

342

[Comparison of MICs of new quinolones obtained using agar-dilution and broth-microdilution procedures].  

PubMed

Minimum inhibitory concentrations (MIC) of new quinolones against both Gram-positive and Gram-negative bacteria obtained using agar-dilution and broth-microdilution procedures were compared. A primary regression curve and a correlation coefficient (r) between 2 MICs for each of ofloxacin, ciprofloxacin, tosufloxacin, sparfloxacin or balofloxacin were calculated. For the 5 quinolones, average correlation coefficients were 0.891 for the Gram-positive bacteria tested, and 0.865 for the Gram-negative bacteria. The range of, correlation coefficients for the Gram-positive bacteria for these drugs was from 0.835 to 0.919, and that for the Gram-negative bacteria was from 0.815 to 0.865. From these data, it is clear that there is a good correlation between the 2 MICs of the new quinolones obtained using the agar-dilution and the broth-microdilution procedures. It was also shown that the value of the slope of the regression curves were nearly the same for the 5 quinolones tested. However, some particular strains of Morganella morganii, Pseudomonas cepacia, Xanthomonas maltophilia, Pseudomonas aeruginosa and Streptococcus pneumoniae exhibited different correlation coefficients from other strains. PMID:7752452

Iwasaki, H; Tsuji, A; Kaneko, Y; Goto, S

1995-03-01

343

Cyclobacterium xiamenense sp. nov., isolated from aggregates of Chlorella autotrophica, and emended description of the genus Cyclobacterium.  

PubMed

A novel Gram-stain-negative, horseshoe-shaped, non-motile bacterium, designated strain KD51(T), forming colonies coloured pink by carotenoid pigments, was isolated from aggregates of the alga Chlorella autotrophica collected from the coastal sea off the city of Xiamen, Fujian Province, China. 16S rRNA gene sequence comparison showed that strain KD51(T) was a member of the genus Cyclobacterium, forming a distinct lineage with Cyclobacterium lianum HY9(T). The 16S rRNA gene sequence similarity between strain KD51(T) and the type strains of species of the genus Cyclobacterium ranged from 92.1?% to 95.2?%. Growth occurred at 4-40 C (optimum, 28 C), in the presence of 3-9?% NaCl (optimum, 3-5?%) and at pH 6-10 (optimum, pH 7.5). The dominant fatty acids (>20?%) of strain KD51(T) were iso-C15?:?0 (32.2?%) and summed feature 3 (comprising C16?:?1?7c and/or C16?:?1?6c; 22.2?%). The DNA G+C content was 41.7 mol% and the only respiratory quinone was menaquinone-7. On the basis of phenotypic data and phylogenetic inference, strain KD51(T) represents a novel species of the genus Cyclobacterium, for which the name Cyclobacterium xiamenense sp. nov. is proposed. The type strain is KD51(T) (?=?CGMCC 1.12432(T)?=?KCTC 32253(T)). An emended description of the genus Cyclobacterium is also proposed. PMID:24277859

Chen, Zhangran; Yang, Luxi; Li, Yi; Lai, Qiliang; Zhang, Huajun; Wei, Jun; Zhou, Yanyan; Lei, Xueqian; Zheng, Wei; Tian, Yun; Xiong, Xiaojing; Zheng, Tianling

2014-03-01

344

Gene cloning, sequence analysis, and expression profiles of a novel ?-ring carotenoid hydroxylase gene from the photoheterotrophic green alga Chlorella kessleri.  

PubMed

In this study, a full-length complementary DNA (cDNA) sequence of ?-ring carotenoid hydroxylase (CHY), designated Ckecyp97a1, was isolated via reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends (RACE) methods. The cloned Ckecyp97a1 cDNA was 2,264-bp in length, and contained an open reading frame (ORF) of 1,944-bp with 5'-terminal untranslated region (UTR) of 66-bp and 3'-terminal UTR of 254-bp and encoded a ?-ring CHY protein of 647 amino acids. The deduced protein had a calculated molecular mass of 71.43kDa with an estimated isoelectric point (pI) of 6.72. Multiple sequence alignment and phylogenetic analysis revealed that Ckecyp97a1 was homologs to known chloroplastic cytochrome P450 (P450) CHY. The typical catalytic motifs of the P450 were highly conserved in the protein sequences of CkeCYP97A1. The Ckecyp97a1 transcriptional expression and carotenoids accumulation were observed under high light (HL) of different wavelengths (white: 390-770nm and blue: 420-500nm). The results revealed that Ckecyp97a1 transcript increased strongly throughout the course of the HL illumination treatment (22-70h) under white HL treatment, while decreased during 10-58h under blue HL treatment. The concentrations of lutein, ?-carotene, and ?-carotene were relatively steady and below the control level under both treatments. The zeaxanthin concentration was higher under white HL treatment than those under control and blue HL treatments. Ckecyp97a1 gene showed different expression patterns under different light wavelengths treatments. The data obtained in this study demonstrates that CkeCYP97A1 is the enzyme responsible for carotenoid hydroxylation involved in HL acclimation for photoheterotrophic green alga Chlorella kessleri CGMCC 4917. PMID:25260905

Yu, Xiaona; Cui, Hongli; Cui, Yulin; Wang, Yan; Li, Xueqin; Liu, Zhaopu; Qin, Song

2014-11-01

345

Novosphingobium marinum sp. nov., isolated from seawater.  

PubMed

A Gram-stain-negative, aerobic, short rod-shaped bacterium, strain LA53(T), was isolated from a deep-sea water sample collected from the eastern Pacific Ocean. Strain LA53(T) grew in the presence of 0-7.0?% (w/v) NaCl and at 15-37 C; optimum growth was observed with 1.0-2.0?% (w/v) NaCl and at 35 C. Chemotaxonomic analysis showed ubiquinone-10 as the predominant respiratory quinone, C18?:?1?7c and summed feature 3 (iso-C15?:?0 2-OH and/or C16?:?1?7c) as major fatty acids, and diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid as major polar lipids. The genomic DNA G+C content was 57.7 mol%. Phylogenetic analyses revealed that strain LA53(T) belongs to the genus Novosphingobium. 16S rRNA gene sequence similarities between strain LA53(T) and the type strains of species of the genus Novosphingobium with validly published names ranged from 93.1 to 96.3?%. In addition, strain LA53(T) could be differentiated from Novosphingobium pentaromativorans DSM 17173(T) and Novosphingobium indicum DSM 23608(T) as well as the type strain of the type species of the genus, Novosphingobium capsulatum DSM 30196(T), by some phenotypic characteristics, including hydrolysis of substrates, utilization of carbon sources and susceptibility to antibiotics. On the basis of phenotypic and genotypic data, strain LA53(T) represents a novel species within the genus Novosphingobium, for which the name Novosphingobium marinum sp. nov. is proposed. The type strain is LA53(T) (?=?CGMCC 1.12918(T)?=?JCM 30307(T)). PMID:25424486

Huo, Ying-Yi; You, Hong; Li, Zheng-Yang; Wang, Chun-Sheng; Xu, Xue-Wei

2015-02-01

346

Nesterenkonia alkaliphila sp. nov., an alkaliphilic, halotolerant actinobacteria isolated from the western Pacific Ocean.  

PubMed

A Gram-staining-positive, aerobic, motile and non-spore-forming actinobacteria, designated strain F10(T), was isolated from a deep-sea sediment of the western Pacific Ocean. Phylogenetic and phenotypic properties of the organism supported that it belonged to the genus Nesterenkonia. Strain F10(T) shared highest 16S rRNA gene sequence similarity of 96.8?% with Nesterenkonia aethiopica DSM 17733(T), followed by Nesterenkonia xinjiangensis YIM 70097(T) (96.7?%) and Nesterenkonia alba CAAS 252(T) (96.6?%). The organism grew at 4-50 C, at pH 7.0-12.0 and in the presence of 0-12?% (w/v) NaCl, with optimal growth occurring at 40 C, at pH 9.0 and in the presence of 1?% (w/v) NaCl. The peptidoglycan type was A4(alpha), l-Lys-Gly-l-Glu. The polar lipid profile of strain F10(T) consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, two unknown glycolipids and two unknown lipids. The isolate contained MK-9 (92?%) and MK-8 (5.8?%) as the major components of the menaquinone system, and anteiso-C17?:?0 (50.9?%) and anteiso-C15?:?0 (29.8?%) as the predominant fatty acids. The G+C content of the genomic DNA of strain F10(T) was 66.2 mol%. Based on phenotypic, genotypic and phylogenetic analyses, strain F10(T) represents a novel species of the genus Nesterenkonia for which the name Nesterenkonia alkaliphila sp. nov. is proposed. The type strain is F10(T) (?=?LMG 28112(T)?=?CGMCC 1.12781(T)?=?JCM 19766(T)?=?MCCC 1A09946(T)). PMID:25389152

Zhang, Gaiyun; Zhang, Yubian; Yin, Xijie; Wang, Shuang

2015-02-01

347

Celeribacter indicus sp. nov., a polycyclic aromatic hydrocarbon-degrading bacterium from deep-sea sediment and reclassification of Huaishuia halophila as Celeribacter halophilus comb. nov.  

PubMed

A taxonomic study was carried out on strain P73(T), which was isolated from deep-sea sediment of the Indian Ocean by enrichment of polycyclic aromatic hydrocarbons. The strain was able to degrade biphenyl, naphthalene, 2-methylnaphthalene, 2,6-dimethylnaphthalene, acenaphthene, anthracene, phenanthrene, dibenzothiophene, dibenzofuran, fluorene, 4-methyldibenzothiophene and fluoranthene, but not pyrene or chrysene. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain P73(T) formed a clade with the genera Celeribacter and Huaishuia within the family Rhodobacteraceae, with highest sequence similarity of 96.98?% to Celeribacter neptunius H 14(T), followed by Huaishuia halophila ZXM137(T) (96.42?%). The bacterium was Gram-stain-negative, oxidase- and catalase-positive, rod-shaped and non-motile. Growth was observed at salinities from 0.5 to 12?% and at temperatures from 10 to 41 C. The principal fatty acids (>10?%) of strain P73(T) were summed feature 8 (C18?:?1?7c/?6c) and C19?:?0?8c cyclo. The sole respiratory quinone was Q-10. The major lipids were phosphatidylglycerol, one unknown aminolipid, one unknown phospholipid and one unknown lipid; a second unknown phospholipid and one unknown glycolipid were present as minor components. The G+C content of the chromosomal DNA was 66.0 mol%. The combined genotypic and phenotypic data show that strain P73(T) represents a novel species of the genus Celeribacter, for which the name Celeribacter indicus sp. nov. is proposed. The type strain is P73(T) (?=?MCCC 1A01112(T)?=?LMG 27600(T)?=?DSM 27257(T)). Phylogenetic study and existing phenotypic information also show that Huaishuia halophila should be transferred to the genus Celeribacter as Celeribacter halophilus comb. nov. (type strain ZXM137(T)?=?MCCC 1A06432(T)?=?CGMCC 1.8891(T)?=?LMG 24854(T)). PMID:25256706

Lai, Qiliang; Cao, Junwei; Yuan, Jun; Li, Fuying; Shao, Zongze

2014-12-01

348

Glycomyces artemisiae sp. nov., an endophytic actinomycete isolated from the roots of Artemisia argyi.  

PubMed

An endophytic actinomycete strain, IXS4(T), was isolated from the root of Artemisia argyi, a medicinal plant collected from Yesanpo located in Laishui county, Hebei province, China. The 16S rRNA gene sequence of strain IXS(T) showed most similarity to Glycomyces mayteni YIM 61331(T) (98.23% 16S rRNA gene sequence similarity), Glycomyces scopariae YIM 56256(T) (98.00%), Glycomyces sambucus E71(T) (97.90%) and Glycomyces algeriensis NRRL B-16327(T) (97.10%). DNA-DNA hybridization values between strain IXS4(T) and the closely related type strains were well below 70%. The strain also showed a number of physiological and biochemical characteristics that were distinct from the closely related species. The strain contained MK-10(H2) and MK-11(H0) as the detected menaquinones. The peptidoglycan was mainly meso-diaminopimelic acid and the whole-cell sugars contained galactose, glucose, mannose, xylose and ribose. The major cellular fatty acids were iso-C14:0, iso-C15:0, iso-C16:0, anteiso-C15:0 and anteiso-C17:0. Based on the genetic and phenotypic properties, it is proposed that strain IXS4(T) represents a novel species of the genus Glycomyces, with the name http://dx.doi.org/10.1601/nm.7671Glycomyces artemisiae sp. nov. The type strain is IXS4(T) (?=?HBUM178000(T) = CGMCC 4.7067(T)?= NBRC 109773(T)). PMID:25052398

Zhang, Xiumin; Ren, Kai; Du, Jiao; Liu, Haiyan; Zhang, Liping

2014-10-01

349

Halomonas huangheensis sp. nov., a moderately halophilic bacterium isolated from a saline-alkali soil.  

PubMed

A novel, Gram-stain-negative, aerobic, rod-shaped, non-motile and moderately halophilic bacterium, designated strain BJGMM-B45(T), was isolated from a saline-alkali soil collected from Shandong Province, China. Growth of strain BJGMM-B45(T) occurred at 10-45 C (optimum, 30 C) and pH 5.0-12.0 (optimum, pH 7.0) on Luria-Bertani agar medium with 1-20?% (w/v) NaCl (optimum, 7-10?%). The predominant respiratory quinone was Q-9. The major cellular fatty acids (>5?%) were C18?:?1?7c, C16?:?0, C19?:?0 cyclo ?8c, summed feature 3, C12?:?0 3-OH and C12?:?0. The genomic DNA G+C content was 57.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BJGMM-B45(T) belonged to the genus Halomonas in the class Gammaproteobacteria. The closest relatives were Halomonas cupida DSM 4740(T) (98.2?% 16S rRNA gene sequence similarity) and Halomonas denitrificans M29(T) (97.8?%). Levels of DNA-DNA relatedness between strain BJGMM-B45(T) and Halomonas cupida CGMCC 1.2312(T) and Halomonas denitrificans DSM 18045(T) were 57.0 and 58.9?%, respectively. On the basis of phenotypic, chemotaxonomic and phylogenetic features, strain BJGMM-B45(T) is considered to represent a novel species of the genus Halomonas, for which the name Halomonas huangheensis sp. nov. is proposed. The type strain is BJGMM-B45(T) (?=?ACCC 05850(T)?=?KCTC 32409(T)). PMID:24425813

Miao, Chaohua; Jia, Fangfang; Wan, Yusong; Zhang, Wei; Lin, Min; Jin, Wujun

2014-03-01

350

Undibacterium terreum sp. nov., isolated from permafrost soil.  

PubMed

The bacterial strain C3(T) was isolated from permafrost soil in Beijicun, Mohe County, Heilongjiang province, China. Cells of strain C3(T) were Gram-stain-negative rods, 0.3-0.4 m in diameter and 1.0-2.6 m in length. Strain C3(T) was strictly aerobic. Growth occurred at 15-37 C but not at 4 or 42 C, at pH 5.0-9.0 (optimum pH 6.0-7.0) and in the presence of 0-8 g NaCl l(-1) (optimum 0-1 g l(-1)). The analysis of 16S rRNA gene sequences indicated that strain C3(T) was phylogenetically related to members of the genus Undibacterium, with similarities ranging from 94.7 to 96.5%. Strain C3(T) contained ubiquinone 8 as the major respiratory quinone. The major cellular fatty acids were summed feature 3 (C16:1?7c/C16:1?6c), C17:0 cyclo, straight-chain C16:0, C12:0 and C10:0, unsaturated C18:1?7c and hydroxylated fatty acids C10:0 3-OH and C12:0 2-OH. The polar lipids were mainly phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The polyamines were putrescine and 2-hydroxyputrescine. The DNA G+C content was 57.4 mol% (determined from Tm). Based on these results, it is concluded that strain C3(T) represents a novel species of the genus Undibacterium, for which the name Undibacterium terreum sp. nov. is proposed, with C3(T) (=CGMCC 1.10998(T)=NBRC 108789(T)) representing the type strain. PMID:23159755

Liu, Yi-Qian; Wang, Bao-Jun; Zhou, Nan; Liu, Shuang-Jiang

2013-06-01

351

Roseicitreum antarcticum gen. nov., sp. nov., an aerobic bacteriochlorophyll a-containing alphaproteobacterium isolated from Antarctic sandy intertidal sediment.  

PubMed

A novel Gram-negative, non-motile bacterium, designated strain ZS2-28(T), was isolated from sandy intertidal sediment samples collected from the coastal regions of the Chinese Antarctic Zhongshan Station on the Larsemann Hills, Princess Elizabeth Land, East Antarctica. Strain ZS2-28(T) was obligately heterotrophic, strictly aerobic, psychrotolerant (growth occurred at 0-33 C) and moderately halophilic (optimal growth in 7-8?% NaCl). A single major peak at 872-874 nm in the infrared absorption spectrum indicated the presence of bacteriochlorophyll a. Poly-?-hydroxybutyrate accumulation and slime production were also detected. The predominant cellular fatty acid was C??:??7c, with C??:? 3-OH, C??:?, C??:? cyclo, C??:??8c cyclo and summed feature 3 (C??:??7c and/or iso-C??:? 2-OH) present in smaller amounts. The respiratory quinone was Q-10. The main polar lipids were phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified aminolipid. The G+C content of the genomic DNA was 63.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZS2-28(T) formed a distinct evolutionary lineage within the clade containing members of the genera Roseibaca, Roseinatronobacter and Rhodobaca of the class Alphaproteobacteria. On the basis of its phylogenetic position, as well as its phenotypic and chemotaxonomic characteristics, strain ZS2-28(T) represents a novel species of a novel genus, for which the name Roseicitreum antarcticum gen. nov., sp. nov. is proposed. The type strain is ZS2-28(T) (?=?CGMCC 1.8894(T) ?=?LMG 24863(T)). PMID:20889763

Yu, Yong; Yan, Shu-Lin; Li, Hui-Rong; Zhang, Xiao-Hua

2011-09-01

352

Sphingobacterium yamdrokense sp. nov., isolated from Lake Yamdrok.  

PubMed

A strictly aerobic and facultatively psychrophilic bacterium, strain 3-0-1(T), was isolated from Lake Yamdrok on the Tibetan Plateau, China. Cells were Gram-negative and short-rod-shaped. Strain 3-0-1(T) formed circular, opaque, yellow colonies, and grew at 0-5% (w/v) NaCl, pH 5.0-11.0 and 5-35C. Phylogenetic analysis based on 16S rRNA gene sequences of various species with validly published names showed that strain 3-0-1(T) belongs to the genus Sphingobacterium, family Sphingobacteriaceae, sharing the highest similarity with Sphingobacterim nematocida M-SX103(T) (96.62%) and less than 95% similarity with all the other species in the genus Sphingobactrium. The predominant isoprenoid quinone of strain 3-0-1(T) was identified as menaquinone 7 (MK-7), the major polar lipid was identified as phosphatidylethanolamine and the DNA G+C content was determined to be 42.5mol%. The predominant cellular fatty acids were identified as summed feature 3 (C16:1 ?7c and/or C16:1 ?6c) (>30%), iso-C15:0 (>20%) and iso-C17:0 3-OH (>10%). Based on the variability of phylogenetic and phenotypic characteristics, strain 3-0-1(T) represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium yamdrokense sp. nov. is proposed. The type strain is 3-0-1(T) (=JCM 19397(T)=CGMCC 1.12560(T)). PMID:25795442

Xiao, Na; Liu, Yongqin; Gu, Zhengquan; Liu, Xiaobo; Jiao, Nianzhi; Liu, Hongcan; Zhou, Yuguang; Shen, Liang

2015-05-01

353

Bacillus cihuensis sp. nov., isolated from rhizosphere soil of a plant in the Cihu area of Taiwan.  

PubMed

A Gram-positive, moderately halotolerant, rod-shaped, spore forming bacterium, designated strain FJAT-14515(T) was isolated from a soil sample in Cihu area, Taoyuan County, Taiwan. The strain grew at 10-35 C (optimum at 30 C), pH 5.7-9.0 (optimum at pH 7.0) and at salinities of 0-5 % (w/v) NaCl (optimum at 1 % w/v). The diagnostic diamino acid of the peptidoglycan of the isolated strain was meso-diaminopimelic acid and major respiratory isoprenoid quinone was MK-7. Major cellular fatty acids were anteiso-C15:0 (40.6 %), iso-C15:0 (20.7 %) and the DNA G+C content of strain FJAT-14515(T) was 37.1 mol %. A phylogenetic analysis based on 16S rRNA gene sequences indicated that strain FJAT-14515(T) belongs to the genus Bacillus, and was most closely related to the reference strains of Bacillus muralis DSM 16288(T) (97.6 %) and Bacillus simplex DSM 1321(T) (97.5 %). Levels of DNA-DNA relatedness between strain FJAT-14515(T) and the reference strains of B. muralis DSM 16288(T) and B. simplex DSM 1321(T) were 27.9 % 3.32 and 44.1 % 0.57, respectively. Therefore, on the basis of phenotypic, chemotaxonomic and genotypic properties, strain FJAT-14515(T) represents a novel species of the genus Bacillus, for which the name Bacillus cihuensis sp. nov. is proposed. The type strain is FJAT-14515(T) (=DSM 25969(T) = CGMCC 1.12697(T)). PMID:25256951

Liu, Bo; Liu, Guo-Hong; Sengonca, Cetin; Schumann, Peter; Wang, Ming-Kuang; Tang, Jian-Yang; Chen, Mei-Chun

2014-12-01

354

Metallosphaera tengchongensis sp. nov., an acidothermophilic archaeon isolated from a hot spring.  

PubMed

Two novel acidothermophilic archaea, strains Ric-A(T) and Ric-F, were isolated from muddy water samples of a sulfuric hot spring located in Tengchong County, Yunnan Province, PR China. The strains were aerobic and facultatively chemolithoautotrophic. Both strains could oxidize S(0) and K2S4O6 for autotrophic growth, and could use organic materials for heterotrophic growth. Growth was observed at 55-75 C and pH 1.5-6.5. The strains could oxidize metal sulfide ores, showing their potential in bioleaching. The DNA G+C contents of strains Ric-A(T) and Ric-F were 41.8 and 41.6 mol%, respectively. Analysis of 16S rRNA gene sequences showed that the two strains shared 99.8 % sequence similarity to each other, but <97 % to other known species of the genus Metallosphaera. DNA-DNA hybridization indicated that the isolates were different strains of a novel species of the genus Metallosphaera. Strains Ric-A(T) and Ric-F also shared a number of physiological and biochemical characteristics that distinguished them from recognized species of the genus Metallosphaera. On the basis of phenotypic, chemotaxonomic and phylogenetic comparisons with their closest relatives, it was concluded that strains Ric-A(T) and Ric-F represent a novel species of the genus Metallosphaera, for which the name Metallosphaera tengchongensis sp. nov. is proposed. The type strain is Ric-A(T) (?= NBRC 109472(T)?= CGMCC 1.12287(T)). PMID:25404480

Peng, Tang-Jian; Liu, Li-Jun; Liu, Chang; Yang, Zhi-Fang; Liu, Shuang-Jiang; Jiang, Cheng-Ying

2015-02-01

355

Tepidibacter mesophilus sp. nov., a mesophilic fermentative anaerobe isolated from soil polluted by crude oil, and emended description of the genus Tepidibacter.  

PubMed

A mesophilic, aerotolerant, endospore-forming, fermentative bacterium, designated strain B1(T), was isolated from soil polluted by crude oil in the Karamay Oil Field, China. Cells were Gram-positive, rod-shaped, 1.1-1.6 m wide and 2.3-4.7 m long, and were motile by means of peritrichous flagella. Growth occurred at 10-40 C and pH 6.0-8.9; optimal growth occurred at 28-32 C and pH 7.3. The optimal concentrations of NaCl and sea salts for growth were 0.5 and 1% (w/v), respectively. The strain was halotolerant and grew in the presence of NaCl or sea salts up to a concentration of 9% (w/v). Substrates utilized as sole carbon sources were beef extract, yeast extract, peptone, tryptone, casein, D-glucose, D-fructose, D-xylose, D-ribose, D-galactose, maltose, L-rhamnose, trehalose, L-valine, DL-alanine plus L-proline and DL-alanine plus L-glycine. The main products of glucose fermentation were ethanol and acetate. iso-C(15:0), iso-C(14:0), C(16:0) and iso-C(13:0) were the major fatty acids. 16S rRNA gene sequence analysis revealed that the isolate belongs to the genus Tepidibacter, showing 94.7 and 94.1% similarity to the type strains of Tepidibacter formicigenes and Tepidibacter thalassicus, respectively. The genomic DNA G+C content of strain B1(T) was 29.8 mol%. On the basis of its phenotypic and genotypic properties, strain B1(T) is suggested to represent a novel species of the genus Tepidibacter, for which the name Tepidibacter mesophilus sp. nov. is proposed. The type strain is B1(T) (=CGMCC 1.5148(T) =JCM 16806(T)). PMID:21335504

Tan, Hai-Qin; Wu, Xiao-Yue; Zhang, Xin-Qi; Wu, Min; Zhu, Xu-Fen

2012-01-01

356

Deinococcus citri sp. nov., isolated from citrus leaf canker lesions.  

PubMed

A Gram-stain-positive, strictly aerobic, non-motile, coccoid bacterium, designated NCCP-154(T), was isolated from citrus leaf canker lesions and was subjected to a polyphasic taxonomic study. Strain NCCP-154(T) grew at 10-37 C (optimum 30 C) and at pH 7.0-8.0 (optimum pH 7.0). The novel strain exhibited tolerance of UV irradiation (>1000 J m(-2)). Based on 16S rRNA gene sequence analysis, strain NCCP-154(T) showed the highest similarity to Deinococcus gobiensis CGMCC 1.7299(T) (98.8?%), and less than 94?% similarity to other closely related taxa. The chemotaxonomic data [major menaquinone, MK-8; cell-wall peptidoglycan type, A3? (Orn-Gly2); major fatty acids, summed feature 3 (C16?:?1?7c/iso-C15?:?0 2-OH; 35.3?%) followed by C16?:?0 (12.7?%), iso-C17?:?1?9c (9.2?%), C17?:?1?8c (7.4?%) and iso-C17?:?0 (6.9?%); major polar lipids made up of several unidentified phosphoglycolipids and glycolipids and an aminophospholipid, and mannose as the predominant whole-cell sugar] also supported the affiliation of strain NCCP-154(T) to the genus Deinococcus. The level of DNA-DNA relatedness between strain NCCP-154(T) and D. gobiensis JCM 16679(T) was 63.33.7?%. The DNA G+C content of strain NCCP-154(T) was 70.0 mol%. Based on the phylogenetic analyses, DNA-DNA hybridization and physiological and biochemical characteristics, strain NCCP-154(T) can be differentiated from species with validly published names. Therefore, it represents a novel species of the genus Deinococcus. The name Deinococcus citri sp. nov. is proposed, with the type strain NCCP-154(T) (?=?JCM 19024(T)?=?DSM 24791(T)?=?KCTC 13793(T)). PMID:25256704

Ahmed, Iftikhar; Abbas, Saira; Kudo, Takuji; Iqbal, Muhammad; Fujiwara, Toru; Ohkuma, Moriya

2014-12-01

357

Bacillus mesonae sp. nov., isolated from the root of Mesona chinensis.  

PubMed

A Gram-stain-positive, short rod-shaped and motile, mildly halotolerant, endospore-forming bacterium, FJAT-13985(T), was isolated from the internal tissues of Mesona chinensis root. Strain FJAT-13985(T) grew at 20-45 C (optimum 30 C) and pH 5.7-9.0 (optimum pH 7.0) and in the presence of 0-2% (w/v) NaCl [optimum 1% (w/v)]. The strain was catalase-positive and oxidase-negative. The cell wall of strain FJAT-13985(T) contained meso-diaminopimelic acid and the predominant isoprenoid quinone was MK-7 (97.4%). The major fatty acids of the strain were anteiso-C15:0 (23.3%) and iso-C15:0 (40.8%). The DNA G+C content was 41.64 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain FJAT-13985(T) is a member of the genus Bacillus and is most closely related to Bacillus drentensis DSM 15600(T) (98.4%), Bacillus vireti DSM 15602(T) (98.2%) and Bacillus novalis DSM 15603(T) (98.3%). DNA-DNA hybridization indicated that relatedness between strain FJAT-13985(T) and its closest relative, B. drentensis DSM 15600(T), was 36.63%. The phenotypic, chemotaxonomic and genotypic properties clearly indicate that strain FJAT-13985(T) represents a novel species of the genus Bacillus, for which the name Bacillus mesonae sp. nov. is proposed. The type strain is FJAT-13985(T) ( = DSM 25968(T)?= CGMCC1.12238(T)). PMID:25013229

Liu, Bo; Liu, Guo-Hong; Hu, Gui-Hing; Chen, Mei-Chun

2014-10-01

358

Marinobacter antarcticus sp. nov., a halotolerant bacterium isolated from Antarctic intertidal sandy sediment.  

PubMed

A Gram-staining-negative, aerobic, motile, oxidase- and catalase-positive, rod-shaped strain, designated ZS2-30(T), was isolated from Antarctic intertidal sandy sediment. The strain grew at 4-35 C (optimum, 25 C) and in 0-25% (w/v) NaCl (optimum, 3.0-4.0%). It could reduce nitrate to nitrite and hydrolyse Tween 80. The predominant cellular fatty acids of strain ZS2-30(T) were summed feature 3 (C(16:1)?7c and/or C(16:1)?6c), C(16:0), C(18:1)?9c, C(16:1)?9c, C(12:0) 3-OH and C(12:0). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an unidentified aminophospholipid. The genomic DNA G+C content of strain ZS2-30(T) was 55.8 mol%. Analyses of 16S rRNA gene sequences revealed that strain ZS2-30(T) was affiliated with the genus Marinobacter. It showed highest 16S rRNA gene sequence similarities to the type strains of three species of the genus Marinobacter, namely Marinobacter maritimus (98.3%), Marinobacter psychrophilus (98.1%) and Marinobacter goseongensis (97.1%), but the DNA-DNA relatedness values between strain ZS2-30(T) and the above three species were all lower than 45%. Moreover, strain ZS2-30(T) could be distinguished from closely related species of the genus Marinobacter by various phenotypic properties. Based on this taxonomic study using a polyphasic approach, strain ZS2-30(T) is considered to represent a novel species in the genus Marinobacter, for which the name Marinobacter antarcticus sp. nov. is proposed. The type strain of Marinobacter antarcticus is ZS2-30(T) (?=?CGMCC 1.10835(T)?=?KCTC 23684(T)). PMID:21984673

Liu, Chang; Chen, Chun-Xiao; Zhang, Xi-Ying; Yu, Yong; Liu, Ang; Li, Guo-Wei; Chen, Xiu-Lan; Chen, Bo; Zhou, Bai-Cheng; Zhang, Yu-Zhong

2012-08-01

359

Halovenus aranensis gen. nov., sp. nov., an extremely halophilic archaeon from Aran-Bidgol salt lake.  

PubMed

A novel red-pigmented halophilic archaeon, strain EB27(T), was isolated from Aran-Bidgol salt lake, a hypersaline playa in Iran. Cells of strain EB27(T) were non-motile and pleomorphic (rods to triangular or disc-shaped). Strain EB27(T) required at least 2.5 M NaCl and 0.1 M MgCl(2) for growth. Optimal growth was achieved at 4 M NaCl and 0.5 M MgCl(2). The optimum pH and temperature for growth were pH 7.5 and 40 C; it was able to grow at pH 6.0-8.0 and 25-50 C. 16S rRNA gene sequence analysis showed that strain EB27(T) is a member of the family Halobacteriaceae; however, levels of 16S rRNA gene sequence similarity were as low as 90.0, 89.3 and 89.1 % to the most closely related haloarchaeal taxa, namely Halalkalicoccus tibetensis DS12(T), Halosimplex carlsbadense 2-9-1(T) and Halorhabdus utahensis AX-2(T), respectively. The DNA G+C content of strain EB27(T) was 61 mol%. Strain EB27(T) contained phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, common phospholipids found in haloarchaea, together with two minor phospholipids. The only quinone present was MK-8(II-H(2)). Physiological, biochemical and phylogenetic differences between strain EB27(T) and recognized genera of extremely halophilic archaea suggest that this strain represents a novel species in a new genus within the family Halobacteriaceae, for which the name Halovenus aranensis gen. nov., sp. nov. is proposed. The type strain of Halovenus aranensis, the type species of the new genus, is strain EB27(T) ( = IBRC-M 10015(T) = CGMCC 1.11001(T)). PMID:21828022

Makhdoumi-Kakhki, A; Amoozegar, M A; Ventosa, A

2012-06-01

360

Haloplanus vescus sp. nov., an extremely halophilic archaeon from a marine solar saltern, and emended description of the genus Haloplanus.  

PubMed

An extremely halophilic archaeon, strain RO5-8T, was isolated from a disused marine solar saltern in China. The cells were pleomorphic and flat. In static liquid medium, cells floated to the surface. Strain RO5-8T stained Gram-negative and colonies were pink-pigmented. It was able to grow at 30-50 degrees C (optimum 40 degrees C), at 2.6-4.3 M NaCl (optimum 3.1 M NaCl), at 0.03-0.5 M MgCl2 (optimum 0.03 M MgCl2) and at pH 5.5-7.5 (optimum pH 6.0-6.5). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 12% (w/v). The major polar lipids of strain RO5-8T were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and one major glycolipid chromatographically identical to the sulfated mannosyl glucosyl diether S-DGD-1. On the basis of 16S rRNA gene sequence analysis, strain RO5-8T was closely related to three strains of Haloplanus natans with similarities of 97.3-97.6%. The DNA G+C content of strain RO5-8T was 62.1 mol%. The DNA-DNA hybridization value between strain RO5-8T and Haloplanus natans JCM 14081T was 51.6%. It was concluded that strain RO5-8T represents a novel species of the genus Haloplanus, for which the name Haloplanus vescus sp. nov. is proposed. The type strain is RO5-8T (=CGMCC 1.8712T =JCM 16055T). PMID:19767368

Cui, Heng-Lin; Gao, Xia; Li, Xin-Yi; Xu, Xue-Wei; Zhou, Yu-Guang; Liu, Hong-Can; Zhou, Pei-Jin

2010-08-01

361

Haloplanus aerogenes sp. nov., an extremely halophilic archaeon from a marine solar saltern.  

PubMed

Halophilic archaeal strain TBN37(T) was isolated from Taibei marine solar saltern near Lianyungang city of Jiangsu province, China. Cells were pleomorphic, flat and contained gas vesicles. Cells of strain TBN37(T) stained Gram-negative and the colonies were pink-pigmented. The strain was able to grow at 25-50 C (optimum, 37-40 C), with 1.4-5.1 M NaCl (optimum, 2.1 M NaCl), with 0-1.0 M MgCl(2) (optimum, 0.01 M MgCl(2)) and at pH 6.0-9.0 (optimum, pH 7.5). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 8?% (w/v). The major polar lipids of strain TBN37(T) were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and one major glycolipid chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1). On the basis of 16S rRNA gene sequence analysis, strain TBN37(T) was closely related to Haloplanus natans and Haloplanus vescus, with the same similarity of 97.4?%. The DNA G+C content of strain TBN37(T) is 64.1 mol%. DNA-DNA hybridization values between strain TBN37(T) and Haloplanus natans JCM 14081(T) and between strain TBN37(T) and Haloplanus vescus RO5-8(T) were 37.6?% and 42.1?%, respectively. It was concluded that strain TBN37(T) represents a novel species of the genus Haloplanus, for which the name Haloplanus aerogenes sp. nov. is proposed. The type strain is TBN37(T) (?=?CGMCC 1.10124(T) ?=?JCM 16430(T)). PMID:20511466

Cui, Heng-Lin; Gao, Xia; Yang, Xin; Xu, Xue-Wei

2011-04-01

362

Halopelagius inordinatus gen. nov., sp. nov., a new member of the family Halobacteriaceae isolated from a marine solar saltern.  

PubMed

Two extremely halophilic archaea, strains RO5-2(T) and RO5-14, were isolated from Rudong marine solar saltern in Jiangsu, China. Cells of the two strains were pleomorphic, motile and stained Gram-negative. Colonies were red-pigmented. Strains RO5-2(T) and RO5-14 were able to grow at 20-50 degrees C (optimum 37 degrees C), at 2.6-4.8 M NaCl (optimum 3.4-3.9 M NaCl), at 0.03-0.7 M MgCl(2) (optimum 0.5 M MgCl(2)) and at pH 5.5-8.0 (optimum pH 6.5-7.0). Cells lyse in distilled water and the minimal NaCl concentration to prevent cell lysis was 12 % (w/v). The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and two major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1). The 16S rRNA gene sequences of strains RO5-2(T) and RO5-14 showed 93.4-93.8 % similarity to the closest cultivated relative, Halosarcina pallida. The DNA G+C content of strains RO5-2(T) and RO5-14 was 61.0 mol% and 59.9 mol%, respectively. The DNA-DNA relatedness between strains RO5-2(T) and RO5-14 was 86.0 %. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains RO5-2(T) and RO5-14 represent a novel species in a new genus within the family Halobacteriaceae, for which the name Halopelagius inordinatus gen. nov., sp. nov. is proposed. The type strain is RO5-2(T) (=CGMCC 1.7739(T) =JCM 15773(T)). PMID:19854878

Cui, Heng-Lin; Li, Xin-Yi; Gao, Xia; Xu, Xue-Wei; Zhou, Yu-Guang; Liu, Hong-Can; Oren, Aharon; Zhou, Pei-Jin

2010-09-01

363

Halobellus rarus sp. nov., a halophilic archaeon from an inland salt lake of China.  

PubMed

Two halophilic archaeal strains, YC21(T) and YC77, were isolated from an inland salt lake of China. Both have pleomorphic rod-shaped cells that lyse in distilled water, stain Gram-negative and form red-pigmented colonies. They are neutrophilic, require at least 2.1M NaCl for growth under the optimum growth temperature of 37C. The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS), two major glycolipids (GL1 and GL2) chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1), respectively. Trace amounts of two unidentified lipids (GL0-1 and GL0-2) were also detected. The 16S rRNA gene sequences of the two strains are 99.9% identical, show 94.0-98.9% similarity to the closest relative members of Halobellus of the family Halobacteriaceae. The rpoB' gene similarity between strains YC21(T) and YC77 is 99.8% and show 90.3-95.3% similarity to the closest relative members of Halobellus. The DNA G+C content of strains YC21(T) and YC77 were 66.1 and 66.2mol%, respectively. The DNA-DNA hybridization value between strain YC20(T) and strain YC77 was 89%, and the two strains showed low DNA-DNA relatedness with Halobellus limi TBN53(T), the most related member of Halobellus. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains YC21(T) and YC77 represent a novel species of the genus Halobellus, for which the name Halobellus rarus sp. nov. is proposed. The type strain is YC21(T) (=CGMCC 1.12121(T)=JCM 18362(T)). PMID:23828176

Zhang, Wen-Jiao; Han, Dong; Qiu, Xing-Xing; Zhao, Mei-Lin; Mou, Yun-Zhuang; Cui, Heng-Lin; Li, Zheng-Rong

2013-09-01

364

Halomicroarcula limicola sp. nov., isolated from a marine solar saltern, and emended description of the genus Halomicroarcula.  

PubMed

Halophilic archaeal strain YGHS32T was isolated from the Yinggehai marine solar saltern near Shanya city of Hainan Province, China. Cells of the strain were pleomorphic and lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. Strain YGHS32T was able to grow at 20-50 C (optimum 37 C), in the presence of 0.9-4.8 M NaCl (optimum 2.1 M NaCl), with 0.005-1.0 M MgCl2 (optimum 0.3 M MgCl2) and at pH 6.0-8.5 (optimum pH 7.5). The minimal NaCl concentration to prevent cell lysis was 5% (w/v). The major polar lipids of the strain were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and four major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether, mannosyl glucosyl diether, glucosyl mannosyl glucosyl diether and a diglycosyl diether. Strain YGHS32T had two dissimilar 16S rRNA genes and both of them were phylogenetically related to those of Halomicroarcula pellucida JCM 17820T (92.9-96.3% sequence similarity). The rpoB' gene sequence similarity between strain YGHS32T and Halomicroarcula pellucida JCM 17820T was 91.3%. The DNA G+C content of strain YGHS32T was 64.0 mol%. The DNA-DNA hybridization value between strain YGHS32T and Halomicroarcula pellucida JCM 17820T was 45%. It was concluded that strain YGHS32T (=CGMCC 1.12129T=JCM 18640T) represents a novel species of the genus Halomicroarcula, for which the name Halomicroarcula limicola sp. nov. is proposed. An emended description of the genus Halomicroarcula is also presented. PMID:24554639

Zhang, Wen-Jiao; Cui, Heng-Lin

2014-05-01

365

Halosarcina limi sp. nov., a halophilic archaeon from a marine solar saltern, and emended description of the genus Halosarcina.  

PubMed

A halophilic archaeon, strain RO1-6(T), was isolated from a marine solar saltern in eastern China. Cells of strain RO1-6(T) were pleomorphic and motile and stained Gram-negative. Strain RO1-6(T) grew well on complex medium and colonies were red-pigmented. It was able to grow at 20-50C (optimum 37C), in 2.1-5.1M NaCl (optimum 3.9 M NaCl), in 0.05-0.70 M MgCl? (optimum 0.30 M MgCl?) and at pH 6.5-8.0 (optimum pH 7.0). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 12?% (w/v). The major polar lipids of strain RO1-6(T) were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and two glycolipids that were chromatographically identical to S-DGD-1 and S?-DGD. The 16S rRNA gene sequence of strain RO1-6(T) showed similarities of 96.9 and 96.4?% to those of the type strains of Halosarcina pallida and Halogeometricum borinquense, respectively, members of the most closely related recognized genera within the family Halobacteriaceae. The DNA G+C content of strain RO1-6(T) was 61.2 mol%. Phenotypic characterization and phylogenetic analysis revealed that strain RO1-6(T) is related to Halosarcina pallida and represents a novel species of the genus Halosarcina, for which the name Halosarcina limi sp. nov. is proposed; the type strain is RO1-6(T) (=CGMCC 1.8711(T) =JCM 16054(T)). PMID:19946053

Cui, Heng-Lin; Gao, Xia; Li, Xin-Yi; Xu, Xue-Wei; Zhou, Yu-Guang; Liu, Hong-Can; Zhou, Pei-Jin

2010-10-01

366

Chryseobacterium takakiae sp. nov., a member of the phylum Bacteroidetes isolated from Takakia lepidozioides.  

PubMed

A Gram-stain-negative, rod-shaped and non-endospore-forming bacterium, designated strain AG1-2(T), was isolated from Takakia lepidozioides collected from the Gawalong glacier in Tibet, China and characterized using a polyphasic taxonomic approach. The predominant fatty acids of strain AG1-2(T) were iso-C15?:?0 (36.0?%), iso-C17:0 3-OH (20.2?%), summed feature 9 (iso-C17:1?9c and/or C16:0 10-methyl, 16.4%) and summed feature 3 (C16:1?7c and/or C16:1?6c, 11.1%). The major polar lipids were phosphatidylethanolamine, three unidentified aminolipids and two unidentified lipids. Strain AG1-2(T) contained MK-6 as the dominant menaquinone, and the genomic DNA G+C content was 37.3 mol%. The phylogenetic analysis based on the 16S rRNA gene sequences showed that strain AG1-2(T) was affiliated to species of the genus Chryseobacterium, and its closest related species were Chryseobacterium taiwanense Soil-3-27(T), Chryseobacterium hispalense AG13(T), Chryseobacterium camelliae THG C4-1(T) and Chryseobacterium taeanense PHA3-4(T) with a sequence similarity of 98.0, 97.8, 97.3 and 97.1%, respectively. However, the DNA-DNA relatedness values between these strains and strain AG1-2(T) were 29, 21, 21 and 45%, respectively. Based on phylogenetic inference and phenotypic data, strain AG1-2(T) is considered to represent a novel species of the genus Chryseobacterium, for which the name Chryseobacterium takakiae sp. nov. is proposed. The type strain is AG1-2(T) (?=?CGMCC 1.12488(T)?=?DSM 26898(T)). PMID:25273512

Zhao, Ran; Chen, Xin Yao; Li, Xue Dong; Chen, Zhi Ling; Li, Yan Hong

2015-01-01

367

Transfer of Bacillus mucilaginosus and Bacillus edaphicus to the genus Paenibacillus as Paenibacillus mucilaginosus comb. nov. and Paenibacillus edaphicus comb. nov.  

PubMed

Bacillus mucilaginosus and Bacillus edaphicus were reclassified based on their 16S rRNA and gyrB gene sequences, DNA-DNA hybridization, fatty acid methyl esters and other taxonomic characteristics. Phylogenetic analysis based on 16S rRNA and gyrB gene sequences indicated that strains of B. mucilaginosus and B. edaphicus were members of the genus Paenibacillus, with over 90.4 % and 70.3 % sequence similarity, respectively. Their DNA G+C contents were 54.5-56.8 mol%. The DNA-DNA relatedness values of B. edaphicus VKPM B-7517(T) with B. mucilaginosus KNP414 and B. mucilaginosus CGMCC 1.236 were 89.2 % and 88.7 %, respectively. The major isoprenoid quinone of B. mucilaginosus and B. edaphicus was MK-7 (94.1-95.7 %). The peptidoglycan type was A1gamma (meso-diaminopimelic acid) and the major polar lipids were phosphatidylglycerol and diphosphatidylglycerol. The major fatty acids were anteiso-C(15 : 0), C(16 : 1)omega11c and C(16 : 0). Phenotypic features and fatty acid profiles supported the similarity of B. mucilaginosus and B. edaphicus to Paenibacillus validus CCTCC 95016(T) and confirmed their relationship with members of the genus Paenibacillus. Therefore, it is proposed that Bacillus mucilaginosus and Bacillus edaphicus be transferred to the genus Paenibacillus as Paenibacillus mucilaginosus comb. nov. (type strain HSCC 1605(T)=VKPM B-7519(T)=VKM B-1480D(T)=CIP 105815(T)=KCTC 3870(T)) and Paenibacillus edaphicus comb. nov. (type strain VKPM B-7517(T)=DSM 12974(T)=CIP 105814(T)), respectively. PMID:19643872

Hu, Xiu-Fang; Li, Shi-Xiao; Wu, Jin-Guang; Wang, Jian-Feng; Fang, Qiong-Lou; Chen, Ji-Shuang

2010-01-01

368

Lysinibacillus varians sp. nov., an endospore-forming bacterium with a filament-to-rod cell cycle.  

PubMed

Six Gram-stain-positive, motile, filamentous and/or rod-shaped, spherical spore-forming bacteria (strains GY32(T), L31, F01, F03, F06 and F07) showing polybrominated diphenyl ether transformation were investigated to determine their taxonomic status. After spore germination, these organisms could grow more than one hundred microns long as intact single cells and then divide into rod cells and form endospores in 33 h. The cell-wall peptidoglycan of these strains was type A4?, the predominant menaquinone was MK-7 and the major fatty acids were iso-C(16:0), iso-C(15:0) and C(16:1)?7C. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were detected in the polar lipid profile. Analysis of the 16S rRNA gene sequences indicated that these strains should be placed in the genus Lysinibacillus and they were most closely related to Lysinibacillus sphaericus DSM 28(T) (99% 16S rRNA gene sequence similarity). The gyrB sequence similarity and DNA-DNA relatedness between strain GY32(T) and L. sphaericus JCM 2502(T) were 81% and 52%, respectively. The G+C content of the genomic DNA of strain GY32(T) was 43.2 mol%. In addition, strain GY32(T) showed differences in nitrate reduction, starch and gelatin hydrolysis, carbon resource utilization and cell morphology. The phylogenetic distance from its closest relative measured by DNA-DNA relatedness and DNA G+C content, and its phenotypic properties demonstrated that strain GY32(T) represents a novel species of the genus Lysinibacillus, for which the name Lysinibacillus varians sp. nov. is proposed. The type strain is GY32(T) (?=?NBRC 109424(T)?=?CGMCC 1.12212(T)?=?CCTCC M 2011307(T)). PMID:25070216

Zhu, Chunjie; Sun, Guoping; Chen, Xingjuan; Guo, Jun; Xu, Meiying

2014-11-01

369

Altererythrobacter xiamenensis sp. nov., an algicidal bacterium isolated from red tide seawater.  

PubMed

A Gram-stain-negative, yellow-pigmented, aerobic bacterial strain, designated LY02(T), was isolated from red tide seawater in Xiamen, Fujian Province, China. Growth was observed at temperatures from 4 to 44 C, at salinities from 0 to 9% and at pH from 6 to 10. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that the isolate was a member of the genus Altererythrobacter, which belongs to the family Erythrobacteraceae. Strain LY02(T) was related most closely to Altererythrobacter marensis MSW-14(T) (97.2% 16S rRNA gene sequence similarity), followed by Altererythrobacter ishigakiensis JPCCMB0017(T) (97.1%), Altererythrobacter epoxidivorans JCS350(T) (97.1%) and Altererythrobacter luteolus SW-109(T) (97.0%). The dominant fatty acids were C(18 : 1)?7c, C(17 : 1)?6c and summed feature 3 (comprising C(16 : 1)?7c and/or C(16 : 1)?6c). DNA-DNA hybridization showed that strain LY02(T) possessed low DNA-DNA relatedness to A. marensis MSW-14(T), A. ishigakiensis JPCCMB0017(T), A. epoxidivorans JCS350(T) and A. luteolus SW-109(T) (mean SD of 33.2 1.3, 32.1 1.0, 26.7 0.7 and 25.2 1.1?%, respectively). The G+C content of the chromosomal DNA was 61.2 mol%. The predominant respiratory quinone was ubiquinone-10 (Q-10). According to its morphology, physiology, fatty acid composition and 16S rRNA gene sequence data, the novel strain most appropriately belongs to the genus Altererythrobacter, but can readily be distinguished from recognized species. The name Altererythrobacter xiamenensis sp. nov. is proposed (type strain LY02(T)?=?CGMCC 1.12494(T)?=?KCTC 32398(T)?=?NBRC 109638(T)). PMID:24158949

Lei, Xueqian; Li, Yi; Chen, Zhangran; Zheng, Wei; Lai, Qiliang; Zhang, Huajun; Guan, Chengwei; Cai, Guanjing; Yang, Xujun; Tian, Yun; Zheng, Tianling

2014-02-01

370

Maribacter thermophilus sp. nov., isolated from an algal bloom in an intertidal zone, and emended description of the genus Maribacter.  

PubMed

A novel facultatively anaerobic, Gram-stain-negative bacterium, designated strain HT7-2(T), was isolated from Ulva prolifera collected from the intertidal zone of Qingdao sea area, China, during its bloom. Cells were rod-shaped (1.9-3.50.4-0.6 m), non-sporulating and motile by gliding. Strain HT7-2(T) was able to grow at 4-50 C (optimum 40-42 C), pH 5.5-8.5 (optimum pH 7.0), 0-8?% (w/v) NaCl (optimum 2-3?%) and 0.5-10?% (w/v) sea salts (optimum 2.5?%). The genomic DNA G+C content was 38.8 mol%. The phylogenetic analysis based on 16S rRNA gene sequences revealed that strain HT7-2(T) belonged to the genus Maribacter with sequence similarity values of 94.5-96.6?%, and was most closely related to Maribacter aestuarii GY20(T) (96.6%). Chemotaxonomic analysis showed that the main isoprenoid quinone was MK-6 and the major fatty acids were iso-C15:0 and unknown equivalent chain-length 13.565. The polar lipids of strain HT7-2(T) consisted of one phosphatidylethanolamine, four unidentified lipids and one unidentified aminolipid. On the basis of the phenotypic, phylogenetic and chemotaxonomic characteristics, strain HT7-2(T) (?=CGMCC 1.12207(T)?=JCM 18466(T)) is concluded to represent a novel species of the genus Maribacter, for which the name Maribacter thermophilus sp. nov. is proposed. An emended description of the genus Maribacter is also proposed. PMID:25269849

Hu, Jing; Yang, Qi-Qi; Ren, Yi; Zhang, Wen-Wu; Zheng, Gang; Sun, Cong; Pan, Jie; Zhu, Xu-Fen; Zhang, Xin-Qi; Wu, Min

2015-01-01

371

Ornithinibacillus halotolerans sp. nov., isolated from a saline soil.  

PubMed

A Gram-staining-positive, aerobic, motile, endospore-forming, rod-shaped bacterium, designated GD04T, was isolated from a saline soil sample taken in southern China and was characterized by means of a polyphasic approach. Growth occurred with 0.5-12% (w/v) NaCl (optimum 1-2%) and at pH 7.0-9.5 (optimum pH 8.0) and 10-45 C (optimum 30 C). According to the results of a phylogenetic analysis, strain GD04T belonged to the genus Ornithinibacillus, and was related most closely to type strains of the species Ornithinibacillus bavariensis and Ornithinibacillus contaminans (96.5 and 96.5% 16S rRNA gene sequence similarities, respectively). The peptidoglycan amino acid type was A4?, containing L-ornithine and d-aspartic acid. The major respiratory quinone was menaquinone-7 (MK-7). The polar lipid profile of strain GD04T contained predominantly diphosphatidylglycerol with moderate amounts of phosphatidylglycerol, phosphatidylinositol, an unknown phospholipid and an unknown lipid, and a minor amount of another unknown lipid. The G+C content of genomic DNA was 39.3 mol%. The dominant cellular fatty acids were iso-C16:0, iso-C15:0 and anteiso-C15:0. The phenotypic, chemotaxonomic, phylogenetic and genotypic data indicated that strain GD04T represents a novel species of the genus Ornithinibacillus, for which the name Ornithinibacillus halotolerans sp. nov. is proposed. The type strain is GD04T (=KCTC 33116T=CGMCC 1.12408T). PMID:24516116

Lu, Qin; Yang, Guiqin; Ma, Chen; Qin, Dongxing; Li, Dingqiang; Zhou, Shungui

2014-05-01

372

Jeotgalicoccus halophilus sp. nov., isolated from salt lakes.  

PubMed

Two slightly halophilic bacterial strains, C1-52(T) and YD-9, were isolated from Daban and Aiding salt lakes in Xinjiang, China, respectively. The isolates were gram-positive, non-endospore-forming, non-motile, facultatively anaerobic cocci. Colonies were pale yellow, and a light pink, diffusible pigment was produced after a few additional days of incubation. The isolates grew optimally with 2-3?% (w/v) NaCl, at pH 7.5 and at 30-35 C. The peptidoglycan type was L-Lys-Gly(3-4)-L-Ala(Gly). The menaquinones were MK-7 (83.2?%) and MK-6 (16.8?%). The major fatty acids (>10?%) were anteiso-C(15?:?0) and iso-C(15?:?0). The DNA G+C content of strains C1-52(T) and YD-9 was 41.2 and 41.0 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains C1-52(T) and YD-9 were closely related to Jeotgalicoccus psychrophilus YKJ-115(T) (98.0 and 97.1?% 16S rRNA gene sequence similarity, respectively), followed by Jeotgalicoccus halotolerans YKJ-101(T) (97.1 and 96.8?%). Strains C1-52(T) and YD-9 shared, respectively, 20 and 11?% DNA-DNA relatedness with J. halotolerans JCM 11198(T) and 8 and 13?% with J. psychrophilus JCM 11199(T). DNA-DNA relatedness between the isolates was 91?%. On the basis of phenotypic and phylogenetic distinctiveness, strains C1-52(T) and YD-9 belonged to the same species, which should be placed in the genus Jeotgalicoccus as a novel species. The name Jeotgalicoccus halophilus sp. nov. is proposed, with the type strain C1-52(T) (?=?CGMCC 1.8911(T) ?=?NBRC 105788(T)). PMID:20802063

Liu, Wen-Yan; Jiang, Lin-Lin; Guo, Chun-Jing; Yang, Su Sheng

2011-07-01

373

Sinomicrobium oceani gen. nov., sp. nov., a member of the family Flavobacteriaceae isolated from marine sediment.  

PubMed

A marine bacterium, designated SCSIO 03483(T), was isolated from a marine sediment sample collected from the Nansha Islands in the South China Sea. The strain produced roundish colonies with diffusible yellow-coloured pigment on nutrient agar medium or marine agar 2216. Optimal growth occurred in the presence of 0-4?% (w/v) NaCl, at pH 7.0 and a temperature range of 28-37 C. 16S rRNA gene sequence analysis indicated that the isolate belonged to the family Flavobacteriaceae and showed relatively high sequence similarity with Imtechella halotolerans K1(T) (92.7?%). Phylogenetic analysis based on nearly complete 16S rRNA gene sequences revealed that the isolate shared a lineage with members of the genera Imtechella, Joostella and Zhouia. Phospholipids were phosphatidylethanolamine, two unidentified aminolipids and three unknown polar lipids. The major respiratory quinone was MK-6 and the major fatty acids were iso-C15?:?0, iso-C17?:?0 3-OH and summed feature 3 (C16?:?1?6c/C16?:?1?7c). The DNA G+C content of strain SCSIO 03483(T) was 38.4 mol%. On the basis of phenotypic, chemotaxonomic and molecular data, strain SCSIO 03483(T) represents a novel species in a new genus in the family Flavobacteriaceae, for which the name Sinomicrobium oceani gen. nov., sp. nov. is proposed. The type strain of Sinobacterium oceani is SCSIO 03483(T) (?=?KCTC 23994(T)?=?CGMCC 1.12145(T)). PMID:22707529

Xu, Ying; Tian, Xin-Peng; Liu, Yu-Juan; Li, Jie; Kim, Chang-Jin; Yin, Hao; Li, Wen-Jun; Zhang, Si

2013-03-01

374

Pelagibacterium nitratireducens sp.nov., a marine Alphaproteobacterium isolated from the East China Sea.  

PubMed

A Gram-negative, rod-shaped, non-spore-forming aerobic bacterium, motile with a single polar flagellum, strain JLT2005(T), was isolated from surface seawater collected from the East China Sea and formed ivory white colonies on a rich organic medium. The strain was positive for catalase, oxidase, and urease. It grew in the presence of 0-12 % (w/v) NaCl (optimum 5 %), at 20-35 C (optimum 25 C), or at pH 6-10 (optimum pH 9). The major fatty acids (>10 %) were C(18:1)?7c, C(19:0)?8c cyclo, C(16:0), and C(18:0). The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and five unidentified glycolipids. Ubiquinone-10 and Ubiquinone-11 were present as the major quinones. The DNA G+C content was 74.3 mol%. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain JLT2005(T) belongs to the genus Pelagibacterium in the family Hyphomicrobiaceae, class Alphaproteobacteria. The closest neighbors were Pelagibacterium halotolerans B2(T) (98.7 % similarity) and Pelagibacterium luteolum 1_C16_27(T) (97.1 % similarity). DNA-DNA relatedness values of strain JLT2005(T) with P. halotolerans B2(T) and with P. luteolum 1_C16_27(T) were 31.6 and 25 %. Evidence from genotypic, chemotaxonomic, and phenotypic data shows that strain JLT2005(T) represents a novel species of the genus Pelagibacterium, for which the name Pelagibacterium nitratireducens sp. nov is proposed. The type strain is JLT2005(T) (=CGMCC 1.10829(T) =JCM 17767(T)). PMID:23299946

Li, Qipei; Xu, Yongle; Liu, Keshao; Cai, Lanlan; Fu, Yingnan; Sun, Jia; Zhang, Rui

2013-05-01

375

Alicyclobacillus aeris sp. nov., a novel ferrous- and sulfur-oxidizing bacterium isolated from a copper mine.  

PubMed

A novel mesophilic, acidophilic, endospore-forming bacterium, designated strain ZJ-6(T), was isolated from Zi-Jin copper mine in Inner Mongolia, China. Cells of strain ZJ-6(T) were rod-shaped, stained Gram-positive or were Gram-variable, and grew aerobically at 25-35 degrees C (optimum, 30 degrees C) and pH 2.0-6.0 (optimum, pH 3.5). 16S rRNA gene sequence analysis showed that strain ZJ-6(T) was related phylogenetically to members of the genus Alicyclobacillus, with 16S rRNA gene sequence similarities of 89.5-94.2 %. Cells contained MK-7 as the major quinone and the DNA G+C content was 51.2 mol%. Strain ZJ-6(T) possessed a number of phenotypic characteristics that differentiated it from recognized Alicyclobacillus species, including its growth temperature, assimilation of various carbon sources, production of acids from a range of compounds, and the ability to grow chemoautotrophically using ferrous iron, elemental sulfur and tetrathionate as electron donors. The predominant cellular fatty acids of strain ZJ-6(T) were anteiso-C(15 : 0) (67.1 %), iso-C(16 : 0) (7.7 %) and anteiso-C(17 : 0) (7.4 %); omega-alicyclic fatty acids were not found. On the basis of these results, it is concluded that strain ZJ-6(T) represents a novel species within the genus Alicyclobacillus, for which the name Alicyclobacillus aeris sp. nov. is proposed; the type strain is ZJ-6(T) (=CGMCC 1.7072(T)=NBRC 104953(T)). PMID:19622665

Guo, Xu; You, Xiao-Yan; Liu, Li-Jun; Zhang, Jia-Yue; Liu, Shuang-Jiang; Jiang, Cheng-Ying

2009-10-01

376

Anoxybacillus vitaminiphilus sp. nov., a strictly aerobic and moderately thermophilic bacterium isolated from a hot spring.  

PubMed

A strictly aerobic, Gram-stain-positive, motile and spore-forming bacterium, strain 3nP4(T), was isolated from the Puge hot spring located in the south-western geothermal area of China. Strain 3nP4(T) grew at 38-66 C (optimum 57-60 C), at pH 6.0-9.3 (optimum 7.0-7.5) and with 0-4?% (w/v) NaCl (optimum 0-0.5?%). Phylogenetic analysis of 16S rRNA gene sequences, as well as DNA-DNA relatedness values, indicated that the isolate represents a novel species of the genus Anoxybacillus, related most closely to Anoxybacillus voinovskiensis DSM 12111(T). Strain 3nP4(T) had diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and one unidentified phospholipid as major polar lipids and iso-C15?:?0 and iso-C17?:?0 as major fatty acids, which are both typical chemotaxonomic characteristics of the genus Anoxybacillus. The mean DNA G+C content of strain 3nP4(T) was 39.20.95 mol% (HPLC). A distinctive characteristic of the novel isolate was its extreme reliance on vitamin mixture or yeast extract for growth. Based on data from this taxonomic study using a polyphasic approach, strain 3nP4(T) is considered to represent a novel species of the genus Anoxybacillus, for which the name Anoxybacillus vitaminiphilus sp. nov. is proposed. The type strain is 3nP4(T) (?=?CGMCC 1.8979(T)?=?JCM 16594(T)). PMID:23728374

Zhang, Xin-Qi; Zhang, Zhen-Li; Wu, Nan; Zhu, Xu-Fen; Wu, Min

2013-11-01

377

Cohnella capsici sp. nov., a novel nitrogen-fixing species isolated from Capsicum annuum rhizosphere soil, and emended description of Cohnella plantaginis.  

PubMed

A novel bacterial strain designated YN-59(T) was isolated from Capsicum annuum rhizosphere soil in China. The isolate was found to be aerobic, Gram-positive, rod-shaped and to form ellipsoidal or oval spores positioned centrally in swollen sporangia. On the basis of 16S rRNA gene sequence analysis, the isolated strain YN-59 was determined to be related to members of genus Cohnella. High levels of 16S rRNA gene sequence similarity were found between strain YN-59 and Cohnella plantaginis DSM 25424(T) (98.5%) and Cohnella ginsengisoli DSM18997(T) (97.3%); the 16S rRNA gene sequence similarities between strain YN-59 and the other strains recognized members of the genus Cohnella were below 97%. The DNA-DNA hybridization values of strain YN-59 with C. plantaginis DSM 25424(T) and C. ginsengisoli DSM18997(T) were 44.28.4 and 28.85.8%, respectively. The DNA G+C content of strain YN-59(T) was determined to be 59.32mol%. The major isoprenoid quinone was identified as MK-7 and the predominant fatty acids as anteiso-C15:0 (45.32%), iso-C16:0 (19.19%), iso-C15:0 (9.65%) and C16:0 (8.91%). The polar lipids of strain YN-59(T) were found to consist of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol; several unidentified phospholipids were also detected. The diagnostic diamino acid in the cell wall was identified as meso-diaminopimelic. On the basis of its phenotypic and genotypic characteristics and levels of DNA-DNA hybridization, strain YN-59(T) is considered to represent a novel species of the genus Cohnella, for which the name Cohnella capsici sp. nov. (type strain YN-59(T)=CGMCC 1.12046(T)=JCM 19168(T)) is proposed. PMID:25367338

Wang, Li-Ying; Wang, Tian-Shu; Chen, San-Feng

2015-01-01

378

Micromonospora zeae sp. nov., a novel endophytic actinomycete isolated from corn root (Zea mays L.).  

PubMed

A novel actinomycete, designated strain NEAU-gq9(T), was isolated from corn root (Zea mays L.) and characterized using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of the genus Micromonospora. On the basis of 16S rRNA gene sequence similarity studies, strain NEAU-gq9(T) was most closely related to Micromonospora zamorensis CR38(T) (99.3%), Micromonospora jinlongensis NEAU-GRX11(T) (99.2%), Micromonospora saelicesensis Lupac 09(T) (99.2%), Micromonospora chokoriensis 2-19(6)(T) (98.9%), Micromonospora coxensis 2-30-b(28)(T) (98.6%) and Micromonospora lupini Lupac 14N(T) (98.5%). Phylogenetic analysis based on the 16S rRNA gene and gyrB gene demonstrated that strain NEAU-gq9(T) is a member of the genus Micromonospora and supported the closest phylogenetic relationship to M. zamorensis CR38(T), M. jinlongensis NEAU-GRX11(T), M. saelicesensis Lupac 09(T), M. chokoriensis 2-19(6)(T) and M. lupini Lupac 14N(T). A combination of DNA-DNA hybridization, morphological and physiological characteristics indicated that the novel strain could be readily distinguished from the closest phylogenetic relatives. Therefore, it is proposed that strain NEAU-gq9(T) represents a novel species of the genus Micromonospora, for which the name Micromonospora zeae sp. nov. is proposed. The type strain is NEAU-gq9(T) (=CGMCC 4.7092(T)=DSM 45882(T)). PMID:24849538

Shen, Yue; Zhang, Yuejing; Liu, Chongxi; Wang, Xiangjing; Zhao, Junwei; Jia, Feiyu; Yang, Lingyu; Yang, Deguang; Xiang, Wensheng

2014-11-01

379

Nonomuraea fuscirosea sp. nov., an actinomycete isolated from the rhizosphere soil of rehmannia (Rehmannia glutinosa Libosch).  

PubMed

A novel actinomycete, designated strain NEAU-dht8(T), was isolated from the rhizosphere soil of rehmannia (Rehmannia glutinosa Libosch) and characterized using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of the genus Nonomuraea. The G+C content of the DNA was 68.47 mol%. On the basis of 16S rRNA gene sequence similarity studies, strain NEAU-dht8(T) was most closely related to Nonomuraea maheshkhaliensis 16-5-14(T) (99.31%), Nonomuraea kuesteri GW 14-1925(T) (98.77%), Nonomuraea coxensis JCM 13931(T) (98.71%), Nonomuraea wenchangensis 210417(T) (98.44?%), Nonomuraea bangladeshensis 5-10-10(T) (98.36%) and Nonomuraea salmonea DSM 43678(T) (98.0%); similarities to other species of the genus Nonomuraea were lower than 98%. Two tree-making algorithms based on 16S rRNA gene sequences showed that the isolate formed a phyletic line with its closest neighbour N. maheshkhaliensis 16-5-14(T). However, the low level of DNA-DNA relatedness allowed the novel isolate to be differentiated from N. maheshkhaliensis 16-5-14(T). Strain NEAU-dht8(T) could also be differentiated from other species of the genus Nonomuraea showing high 16S rRNA gene sequence similarity (98-98.77%) by morphological and physiological characteristics. Thus, strain NEAU-dht8(T) is considered to represent a novel species of the genus Nonomuraea, for which the name Nonomuraea fuscirosea sp. nov. is proposed. The type strain is NEAU-dht8(T) (?=?CGMCC 4.7104(T)?=?DSM 45880(T)). PMID:24368692

Zhang, Xinhui; Zhang, Yuejing; Zhao, Junwei; Liu, Chongxi; Wang, Shurui; Yang, Lingyu; He, Hairong; Xiang, Wensheng; Wang, Xiangjing

2014-04-01

380

Streptomyces maoxianensis sp. nov., a novel actinomycete isolated from soil in Maoxian, China.  

PubMed

A novel actinomycete, designated strain NEAU-Spg16(T), was isolated from a soil sample from a pine forest in Songpinggou, Maoxian, southwest China. A polyphasic taxonomic study was carried out to establish the status of strain NEAU-Spg16(T). The cell wall peptidoglycan was found to contain LL-diaminopimelic acid and glycine. The major menaquinones were identified as MK-9(H8), MK-9(H4) and MK-9(H6). The phospholipid profile was found to contain diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and an unidentified phospholipid. The major fatty acids were identified as iso-C16:0, C18:0, C16:0 and iso-C15:0. 16S rRNA gene sequence similarity studies showed that strain NEAU-Spg16(T) belongs to the genus Streptomyces with the highest sequence similarity to Streptomyces nitrosporeus DSM 40023(T) (98.6%). However, phylogenetic analysis based on the 16S rRNA gene sequence indicated that it is most closely related to Streptomyces scopuliridis DSM 41917(T) (98.2% sequence similarity). A combination of DNA-DNA hybridization results and some phenotypic characteristics indicated that strain NEAU-Spg16(T) can be clearly differentiated from S. scopuliridis DSM 41917(T) and S. nitrosporeus DSM 40023(T). Therefore, it is concluded that strain NEAU-Spg16(T) represents a novel species of the genus of Streptomyces, for which the name Streptomyces maoxianensis sp. nov. is proposed. The type stain is NEAU-Spg16(T) (=CGMCC 4.7139(T)=DSM 42137(T)). PMID:25663056

Guan, Xuejiao; Liu, Chongxi; Zhao, Junwei; Fang, Baozhu; Zhang, Yuejing; Li, Lianjie; Jin, Pinjiao; Wang, Xiangjing; Xiang, Wensheng

2015-05-01