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1

N-demethylation of neonicotinoid insecticide acetamiprid by bacterium Stenotrophomonas maltophilia CGMCC 1.1788  

Microsoft Academic Search

Our previous study found that Stenotrophomonas maltophilia CGMCC 1.1788 could hydroxylate imidacloprid (IMI) to 5-hydroxy IMI. Here we first report that S. maltophilia CGMCC 1.1788 can demethylate acetamiprid (AAP) to form IM 2-1 that was characterized by HPLC-MS\\/MS and NMR. IM 2-1 retained\\u000a only 10.5% contact activity and 13.1% oral activity of AAP against horsebean aphid. Time course of biotransformation

Ting Chen; Yi-Jun Dai; Juan-Fang Ding; Sheng Yuan; Jue-Ping Ni

2008-01-01

2

Hydroxylation of thiacloprid by bacterium Stenotrophomonas maltophilia CGMCC1.1788.  

PubMed

Chloropyridinyl neonicotinoid insecticides play a major role in crop protection and flea control on cats and dogs. Imidacloprid, thiacloprid and acetamiprid have in common the 6-chloro-3-pyridinylmethyl group but differ in the nitroguanidine or cyanoamidine substituent on an acyclic or cyclic moiety. Our previous study found that Stenotrophomonas maltophilia CGMCC 1.1788 could hydroxylate imidacloprid to 5-hydroxy imidacloprid, and 5-hydroxy imidacloprid was easily converted to 10-19 times higher insecticidal olefin imidacloprid against aphid or whitefly. Acetamiprid could be transformed by S. maltophilia to form N-demethylation product(IM 2-1). In this paper, we examined S. maltophilia CGMCC 1.1788's ability of transformation of thiacloprid. S. maltophilia CGMCC 1.1788 can hydroxylate thiacloprid to 4-hydroxy thiacloprid characterized by HPLC-MS/MS and NMR analysis, however 4-hydroxy thiacloprid could not be converted to olefin thiacloprid under acid conditions like imidacloprid, whereas oxidized and decyonated simultaneously to form 4-ketone thiacloprid imine in alkaline solution. Bioassays indicated that 4-hydroxy thiacloprid had 156 times lower insecticidal activity than thiacloprid, and the ketone-imine derivative almost had no toxicity towards aphid. Though both imidacloprid and thiacloprid are hydroxylated by S. maltophilia CGMCC 1.1788 at the same carbon atom position, however the structural difference between in imidacloprid and thiacloprid, originate the entire discrepancy in bioefficacy of metabolite and its further degrading pathway. These results explain that why thiacloprid is classified as not relevant grade for soil and seed applications, whereas imidacloprid is recommended and acetamiprid is limited. PMID:19421875

Zhao, Yin-Juan; Dai, Yi-Jun; Yu, Ci-Gang; Luo, Jun; Xu, Wen-Ping; Ni, Jue-Ping; Yuan, Sheng

2009-05-07

3

Biotransformation of thianicotinyl neonicotinoid insecticides: diverse molecular substituents response to metabolism by bacterium Stenotrophomonas maltophilia CGMCC 1.1788.  

PubMed

The carbon atom that neighbors the tertiary amine attached to the 6-chloro-3-pyridinylmethyl moiety is the key active site in the hydroxylation of the neonicotinoids imidacloprid and thiacloprid as well as in the demethylation of acetamiprid by Stenotrophomonas maltophilia CGMCC 1.1788. In this study, thianicotinyl neonicotinoid insecticides having diverse molecular substituents were biotransformed by S. maltophilia CGMCC 1.1788. The results indicated that the substitution of 6-chloropyridyl in imidacloprid with 2-chlorothiazol in imidaclothiz did not affect the hydroxylation of imidaclothiz and its hydroxylated site, while the oxadiazinane ring in thiamethoxam was not hydroxylated or opened. Moreover, the N-methyl group in clothianidin and thiamethoxam was not demethylated by S. maltophilia CGMCC 1.1788. The biotransformation of imidaclothiz was inhibited by piperonyl butoxide, implying that both hydroxylation and dehydrogenation are mediated by a P450 monooxygenase. The bioassay results suggested that the activity of 5-hydroxy and olefin imidaclothiz was similar but less than that of imidaclothiz against the horsebean aphid Aphis craccivora and mosquito larva Culex pipiens, while 5-hydroxy IMT showed weak activity against the brown planthopper Nilaparvata lugens. PMID:20149644

Dai, Yijun; Zhao, Yinjuan; Zhang, Wenjian; Yu, Cigang; Ji, Weiwei; Xu, Wenping; Ni, Jueping; Yuan, Sheng

2010-02-09

4

Screening, purification and characterization of a novel cold-active and organic solvent-tolerant lipase from Stenotrophomonas maltophilia CGMCC 4254.  

PubMed

An extracellular organic solvent-tolerant and cold-active lipase producing bacterium was isolated from oil-contaminated soil samples, and identified taxonomically as Stenotrophomonas maltophilia. The lipase from S. maltophilia CGMCC 4254 (SML) was purified 60.5-fold to homogeneity with 38.9U/mg specific activity. Partially purified SML displayed remarkable stability in 50% and 100% (v/v) hydrophobic organic solvents after incubation for 7days. The enzyme also retained more than 50% of its residual activity in several pure hydrophilic organic solvents after incubation for 7days. SML showed 57% maximum activity at 5°C, and had optimal activity at 35°C. These unique properties of SML make it promising as a biocatalyst for industrial processes. PMID:24050922

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

2013-08-27

5

Stenotrophomonas maltophilia endocarditis of prosthetic mitral valve.  

PubMed

We present a 78-year-old woman with prosthetic valve endocarditis due to Stenotrophomonas maltophilia (S. maltophilia) 3 years after mitral valve replacement. Administration of sulfamethoxazole-trimethoprim was effective; however, it was discontinued because of side effects, which led to failure of antibiotic therapy. Complications of multiple cerebral infarction and paravalvular abscess developed. Although the prosthetic valve was removed 50 days after admission, she died 4 months after surgery. S. maltophilia has been increasingly being considered as a serious nosocomial pathogen. S. maltophilia endocarditis is rare; however, it should be recognized as a possible life-threatening disease in patients with prosthetic valve. PMID:20720357

Katayama, Takuji; Tsuruya, Yoshio; Ishikawa, Susumu

2010-08-13

6

Infective Endocarditis due to Stenotrophomonas (Xanthomonas) maltophilia  

Microsoft Academic Search

Stenotrophomonas maltophilia (formerly Xanthomonas maltophilia) is a gram-negative bacillus increasingly associated with serious nosocomial infections. Here, the case of a 69-year-old female patient who developed prosthetic valve endocarditis associated with this organism is described. A review of the literature revealed only 18 previous reports; eight involved native valves, the remainder prosthetic valves. Most cases were associated with risk factors, including

R. G. Munter; A. M. Yinnon; Y. Schlesinger; C. Hershko

1998-01-01

7

Infective endocarditis due to Stenotrophomonas (Xanthomonas) maltophilia  

Microsoft Academic Search

Stenotrophomonas maltophilia (formerlyXanthomonas maltophilia) is a gram-negative bacillus increasingly associated with serious nosocomial infections. Here, the case of a 69-year-old female patient who developed prosthetic valve endocarditis associated with this organism is described. A review of the literature revealed only 18 previous reports; eight involved native valves, the remainder prosthetic valves. Most cases were associated with risk factors, including intravenous

R. G. Munter; A. M. Yinnon; Y. Schlesinger; C. Hershko

1998-01-01

8

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

9

Faucet aerators: A source of patient colonization with Stenotrophomonas maltophilia  

Microsoft Academic Search

Background: Multiple nosocomial outbreaks have been linked to contaminated water sources within the hospital. We report in this article a cluster of patients in a surgical intensive care unit who were colonized or infected with Stenotrophomonas maltophilia . Methods: This study was conducted at an acute care academic hospital. Patients colonized or infected with S maltophilia were identified by prospective

David J. Weber; William A. Rutala; Cherie N. Blanchet; Michelle Jordan; Maria F. Gergen

1999-01-01

10

A specific polymerase chain reaction method to identify Stenotrophomonas maltophilia.  

PubMed

Stenotrophomonas maltophilia is a multidrug-resistant nosocomial pathogen that is difficult to identify unequivocally using current methods. Accordingly, because the presence of this microorganism in a patient may directly determine the antimicrobial treatment, conventional polymerase chain reaction (PCR) and real-time PCR assays targeting 23S rRNA were developed for the specific identification of S. maltophilia. The PCR protocol showed high specificity when tested against other species of Stenotrophomonas, non-fermentative Gram-negative bacilli and 100 clinical isolates of S. maltophilia previously identified using the Vitek system. PMID:23778655

Gallo, Stephanie Wagner; Ramos, Patrícia Locosque; Ferreira, Carlos Alexandre Sanchez; de Oliveira, Sílvia Dias

2013-05-01

11

Stenotrophomonas maltophilia resistant to trimethoprim - sulfamethoxazole: an increasing problem  

PubMed Central

Stenotrophomonas maltophilia (S. maltophilia) has recently emerged as an important nosocomial pathogen. Treatment of invasive infections caused by this organism is difficult as the bacterium is frequently resistant to a wide range of commonly used antimicrobials. Trimethoprim-sulfamethoxazole (TMP – SXT) is recommended as the agent of choice for the treatment of S. maltophilia infections. However, the development of resistance to this antibiotic represents a real challenge to laboratorians and clinicians. This letter describes the first isolation of S. maltophilia resistant to TMP – SXT from two patients treated at Riyadh Armed Forces Hospital which is a major tertiary hospital in Saudi Arabia.

Al-Jasser, Asma Marzouq

2006-01-01

12

Meningitis due to Stenotrophomonas maltophilia after a Neurosurgical Procedure  

PubMed Central

Stenotrophomonas maltophilia is an aerobic, glucose non- fermentative, gram negative bacillus, which is being increasingly recognized as a cause of serious infections such as bacteraemia, urinary tract infections, respiratory tract infections, skin and soft tissue infections, endocarditis, meningitis and ocular infections in hospitalized patients. The treatment of invasive S. maltophilia infections is difficult, as this pathogen shows high levels of intrinsic or acquired resistance to different antibiotics, thus reducing the options which are available for treatment. Meningitiscaused by S. maltophilia is rarely encountered and so its experience is also limited. We are describing here a case of a six months old, male child who developed meningitis caused by Stenotrophomonas maltophilia, after he underwent a neurosurgical procedure.

Sood, Smita; Vaid, Vivek Kumar; Bhartiya, Hemant

2013-01-01

13

Immunostimulatory Properties of the Emerging Pathogen Stenotrophomonas maltophilia  

Microsoft Academic Search

Stenotrophomonas maltophilia is a multiple-antibiotic-resistant opportunistic pathogen that is being isolated with increasing frequency from patients with health-care-associated infections and especially from patients with cystic fibrosis (CF). While clinicians feel compelled to treat infections involving this organism, its potential for virulence is not well established. We evaluated the immunostimulatory properties and overall virulence of clinical isolates of S. maltophilia using

Valerie J. Waters; Marisa I. Gomez; Grace Soong; Sunil Amin; Robert K. Ernst; Alice Prince

2007-01-01

14

D -Aminoacylase from a novel producer: Stenotrophomonas maltophilia ITV0595  

Microsoft Academic Search

  A novel bacterial strain producing D-aminoacylase was isolated from organic waste and identified as Stenotrophomonas maltophilia ITV-0595. The isolation was performed using N-acetyl-D-phenylglycine (NAcDPG) as the sole source of C and N. The optimum pH for enzyme expression was 8 at 37°C. Using N-Ac-DPG\\u000a concentrations from 0.5 up to 3% w\\/v, it was observed that at the 1% level, the

F E Muñiz-Lozano; G Dom?nguez-Sánchez; Y D?az-Viveros; D M Barradas-Dermitz

1998-01-01

15

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.

Denton, Miles; Kerr, Kevin G.

1998-01-01

16

Stenotrophomonas Maltophilia Su?larinin Klinik Önemi  

Microsoft Academic Search

Özet: Esas olarak nozokomiyal bir patojen olan S. maltophilia, siklikla eri?kinlerin orofarinkslerinden, balgamlarindan ve içinde ya?adi?imiz birçok ortamdan izole edilen bir bakteridir. Bu bakterinin neden oldu?u klinik tablolar içerisinde en sik üriner sistem ve yara infeksiyonlari gözlenir. Bazi kaynaklarda firsatçi Pseudomonas'lar içerisinde ele alinip incelenen bu bakteri, esas olarak nozokomiyal infeksiyonlardaki rolü ile dikkati çekmektedir. Antibiyotiklere dirençli olmasi di?er bir

Dilek Dülger

17

Genome Sequence of Stenotrophomonas maltophilia Strain AU12-09, Isolated from an Intravascular Catheter  

PubMed Central

Stenotrophomonas maltophilia is an opportunistic nosocomial pathogen that is characterized by its high-level intrinsic resistance to a variety of antibiotics and its ability to form biofilms. Here, we report the draft genome sequence of Stenotrophomonas maltophilia AU12-09, isolated from an intravascular catheter tip.

Morrison, Mark; O Cuiv, Paraic; Evans, Paul; Rickard, Claire M.

2013-01-01

18

Stenotrophomonas maltophilia in the rhizosphere of oilseed rape — occurrence, characterization and interaction with phytopathogenic fungi  

Microsoft Academic Search

Isolates of Stenotrophomonas maltophilia have been isolated from the rhizosphere of oilseed rape. The percentage of S. maltophilia in this habitat was determined using a selective medium according to Juhnke and Des Jardin (1989). The average number of S. maltophilia per gramme root (wet weight) was 107 cfu, 3.7% of the total bacterial number. Selected strains were screened for their

Gabriele Berg; Petra Marten; Günter Ballin

1996-01-01

19

Stenotrophomonas maltophilia pneumonia in cancer patients without traditional risk factors for infection, 1997–2004  

Microsoft Academic Search

In order to elucidate the spectrum of Stenotrophomonas maltophilia pneumonia in cancer patients without traditional risk factors, 44 cancer patients (cases) with S. maltophilia pneumonia in whom S. maltophilia pneumonia risk factors were not present were compared with two S. maltophilia pneumonia risk groups (controls) including 43 neutropenic non-intensive care unit (ICU) and 21 non-neutropenic ICU patients.\\u000a The case and

G. Aisenberg; K. V. Rolston; B. F. Dickey; D. P. Kontoyiannis; I. I. Raad; A. Safdar

2007-01-01

20

Stenotrophomonas maltophilia endophthalmitis following cataract surgery: clinical and microbiological results  

PubMed Central

Background Stenotrophomonas maltophilia is a Gram-negative organism known to cause opportunistic infections. It is a rare source of endophthalmitis, often in the setting of trauma, but has been reported following cataract extraction. The purpose of this study was to evaluate antimicrobial sensitivities, clinical characteristics, and treatment outcomes in patients with endophthalmitis caused by S. maltophilia following cataract extraction. Methods A retrospective case review of records from January 1, 1990 to June 30, 2010 was performed at the Bascom Palmer Eye Institute. Results Eight cases of S. maltophilia endophthalmitis were identified following cataract surgery. Initial visual acuity ranged from 20/200 to light perception. Time to diagnosis with cultures was 2–118 days. Patients received either intravitreal tap and inject (n = 5) or pars plana vitrectomy with intravitreal antibiotic injections (n = 3). All patients had vitreous or anterior chamber cultures positive for S. maltophilia. Seven of seven isolates tested were found to be sensitive to ceftazidime. Seven of eight isolates were sensitive to polymyxin B, six of eight isolates were sensitive to amikacin, and five of the seven isolates tested were sensitive to ciprofloxacin. Two of four tested isolates were sensitive to trimethoprim-sulbactam. All eight isolates were resistant to gentamicin and seven of the seven tested isolates were resistant to imipenem. All patients received intravitreal ceftazidime as part of the initial treatment regimen. Final visual acuity ranged from 20/25 to 4/200. Conclusion S. maltophilia endophthalmitis is a rare source of endophthalmitis following cataract surgery. A case series of eight independent patients is reported, along with antibiotic resistance profiles and clinical outcomes. Isolates showed sensitivity to ceftazidime, amikacin, and polymyxin, with variable sensitivity to other antibiotics, therefore differing from previous reports.

Chang, Jonathan S; Flynn, Harry W; Miller, Darlene; Smiddy, William E

2013-01-01

21

Kinetics of growth and aniline degradation by Stenotrophomonas maltophilia  

SciTech Connect

A pure bacterial culture of Stenotrophomonas maltophilia, capable of using aniline as a sole carbon source, was isolated. Kinetic experiments were conducted to develop a mathematical model that describes accurately the growth and utilization rates of the microorganism on the aniline and an alternate carbon source (glucose) individually and on their mixture. The growth of microorganisms and substrate utilization could be well described by using Monod expressions for limiting substrates. The presence of glucose in the culture medium did not repress aniline catabolism but simultaneous utilization was observed. When both substrates were present, the utilization of one substrate had a considerable effect on the utilization of the other. These effects were shown to be predicted by a mathematical model based on a modified Monod expression. The proposed model was found capable of describing accurately cellular growth as well as aniline and glucose biodegradation.

Zissi, U.S.; Lyberatos, G.C.

1999-01-01

22

Adhering ability of Stenotrophomonas maltophilia is dependent on growth conditions.  

PubMed

The growth conditions are known to influence the bacterial adhesion to different kinds of surfaces. In the present study the adhering ability of Stenotrophomonas maltophilia, on growth in nutrient rich media (Tryptic Soy Broth (TSB)) and minimal media (Luria Bertani (LB)) was checked by viable cell count and spectrophotometric method. TSB grown S. maltophilia showed higher adhesion compared to bacteria grown in LB broth, to both biotic and abiotic surfaces. However, when bacteria were grown in LB broth supplemented with different concentrations of glucose, under aerobic conditions, the bacteria grown at lower glucose concentration (2 gm/l) showed maximum adhesion to abiotic surfaces (polystyrene microtiter plate) compared to biotic surfaces (mouse trachea, mouse tracheal mucus and HEp-2 cells line). Maximum adhesion to biotic surfaces was seen with cells grown at 4 gm/l of glucose concentration. On the contrary if the cell was grown under microaerophilic conditions maximum adhesion to abiotic and biotic surfaces was achieved with bacteria grown at 1 gm/l and 2 gm/l of glucose concentration respectively. A negative correlation was observed between glucose concentrations and pH of media, the latter declined faster under microaerophilic conditions as compared to aerobic condition. PMID:22073545

Zgair, Ayaid K; Chhibber, Sanjay

23

Biofilm Compared to Conventional Antimicrobial Susceptibility of Stenotrophomonas maltophilia Isolates from Cystic Fibrosis Patients  

PubMed Central

Stenotrophomonas maltophilia is a multidrug-resistant organism increasingly isolated from the lungs of cystic fibrosis (CF) patients. One hundred twenty-five S. maltophilia isolates from 85 CF patients underwent planktonic and biofilm susceptibility testing against 9 different antibiotics, alone and in double antibiotic combinations. When S. maltophilia isolates were grown as a biofilm, 4 of the 10 most effective antibiotic combinations included high-dose levofloxacin and 7 of the 10 combinations included colistin at doses achievable by aerosolization.

Wu, Kitty; Yau, Yvonne C. W.; Matukas, Larissa

2013-01-01

24

Different utilizable substrates have different effects on cometabolic fate of imidacloprid in Stenotrophomonas maltophilia.  

PubMed

Imidacloprid, the largest selling insecticide in the world, is more stable in soil, and its environmental residue and effects are attracting people's close attention. One of imidacloprid metabolism pathways was degraded to CO2 through olefin imidacloprid pathway. Here, we report that sucrose as a utilizable substrate enhanced the cometabolism of imidacloprid by Stenotrophomonas maltophilia CGMCC 1.1788 to produce 5-hydroxy imidacloprid, whereas when succinate was used as a utilizable substrate, 5-hydroxy imidacloprid from imidacloprid was transformed to olefin imidacloprid, and the latter was further degraded. The hydroxylation of imidacloprid required NAD(P)H, whereas the dehydration of 5-hydroxy imidacloprid to form olefin imidacloprid required succinate rather than NAD(P)H. NADPH greatly favored the hydroxylation of imidacloprid more than NADH, and NADPH inhibited the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid, but NADH did not. Therefore, sucrose may be metabolized through hexose monophosphate pathway to produce mainly NADPH which participated in the hydroxylation of imidacloprid to 5-hydroxy imidacloprid and meanwhile inhibited the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid, whereas succinate may be metabolized mainly through the tricarboxylic acid cycle to produce NADH which was involved in hydroxylation of imidacloprid to 5-hydroxy imidacloprid but did not inhibit the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid. Our results have a significant meaning in further understanding the influence of different utilizable substrates on the cometabolic pathways and the fate of environmental imidacloprid. PMID:23053094

Liu, Zhonghua; Dai, Yijun; Huan, Yu; Liu, Zhenxing; Sun, Lei; Zhou, Qianwen; Zhang, Wenjian; Sang, Qi; Wei, Hua; Yuan, Sheng

2012-10-04

25

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

Microsoft Academic Search

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

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

2008-01-01

26

Association between Stenotrophomonas maltophilia and lung function in cystic fibrosis  

PubMed Central

Background: Stenotrophomonas maltophilia (SM) is a Gram-negative non-fermenting bacteria cultured from the sputum of patients with cystic fibrosis (CF). To date, no information is available regarding the effect of this organism on lung function in CF. Methods: A cohort study was conducted to assess the effect of SM on lung function among CF patients aged ?6 years in the CF Foundation National Patient Registry from 1994 to 1999. Repeated measures regression was used to assess the association between SM and lung function. Results: The cohort consisted of 20 755 patients with median age at entry of 13.8 years and median follow up time of 3.8 years; 2739 patients (13%) were positive at least once for SM and 18 016 (87%) were never positive. After adjusting for sex, height and age, patients with SM had a mean forced expiratory volume in 1 second which was 0.09 l less (95% CI 0.05 to 0.14) than those without SM. The mean rate of decline associated with SM positivity was 0.025 l/year (95% CI 0.012 to 0.037) but, after adjusting for confounders (sex, height, weight, intravenous antibiotic courses, hospital admissions, pancreatic insufficiency, and Pseudomonas aeruginosa and Burkholderia cepacia status), the mean rate of decline decreased to 0.008 l/year (–0.008, 95% CI –0.019 to 0.003). Conclusions: Although CF patients with SM have worse lung function at the time of positivity, no association was found between SM and increased rate of decline after controlling for confounders.

Goss, C; Mayer-Hamblett, N; Aitken, M; Rubenfeld, G; Ramsey, B

2004-01-01

27

Persistence and variability of Stenotrophomonas maltophilia in cystic fibrosis patients, Madrid, 1991-1998.  

PubMed Central

During 1991 to 1998 at least one Stenotrophomonas maltophilia pulmonary infection was observed in 25 (24%) of 104 cystic fibrosis patients at the same unit of our hospital in Spain. Ribotyping and pulse-field gel electrophoresis (PFGE) characterization of 76 S. maltophilia isolates from these patients indicated an overall clonal incidence of 47.1%, reflecting new strains in 44% of patients with repeated positive cultures for S. maltophilia. Six patients with repeated episodes were persistently colonized (> or = 6 months) with the same strain. S. maltophilia bacterial counts were higher (geometric mean, 2.9 x 10(8) cfu/mL) in patients with repeated episodes than in those with a single episode (8.4 x 10(4) cfu/mL, p < 0.01). Single episodes of S. maltophilia occurred in patients < 10 years of age (43% [6/14]), whereas chronic colonization occurred more frequently in older patients (> 16 years of age).

Valdezate, S.; Vindel, A.; Maiz, L.; Baquero, F.; Escobar, H.; Canton, R.

2001-01-01

28

Genome Sequence of Stenotrophomonas maltophilia RR-10, Isolated as an Endophyte from Rice Root  

PubMed Central

Stenotrophomonas maltophilia is an endophyte which plays important roles in agricultural production as a plant growth-promoting bacterium. Here, we present the draft genome sequence of strain RR-10, which was isolated from a rice root in a rice field of China.

Zhu, Bo; Liu, He; Tian, Wen-Xiao; Fan, Xiao-Ying; Li, Bin; Zhou, Xue-Ping

2012-01-01

29

TRANSFORMATIONS OF SELENATE AND SELENITE BY STENOTROPHOMONAS MALTOPHILIA ISOLATED FROM A SELENIFEROUS AGRICULTURAL DRAINAGE POND SEDIMENT  

Technology Transfer Automated Retrieval System (TEKTRAN)

A Gram-negative bacterium, identified as Stenotrophomonas maltophilia by fatty acid analysis and 16S rRNA sequencing, was isolated from a seleniferous agricultural evaporation pond sediment collected in the Tulare Lake Drainage District, California. In cultures exposed to the atmosphere, the organi...

30

Complicated features in a young child with influenza B virus pneumonia and co-infection with Stenotrophomonas maltophilia.  

PubMed

A 3.5-year-old child with influenza B virus pneumonia developed pneumomediastinum and subcutaneous emphysema on the 3rd day of illness. Bronchoscopy demonstrated obstruction of the left main bronchus by mucopurulent sputum. Culture of the broncho-alveolar lavage yielded Stenotrophomonas maltophilia. After the respiratory complications resolved (11 days), the patient developed neurological symptoms and was diagnosed as acute disseminated encephalomyelitis (ADEM). Stenotrophomonas maltophilia was probably a factor in the development of pneumomediastinum. To our knowledge, this is the first case report of influenza virus infection with Stenotrophomonas maltophilia co-infection associated with spontaneous pneumomediastinum. PMID:21575322

Chen, S-H; Huang, I-A; Wu, C-T; Hsia, S-H; Hung, P-C; Chiu, C-H

2011-01-01

31

Functional Characterization of the RNA Chaperone Hfq in the Opportunistic Human Pathogen Stenotrophomonas maltophilia  

PubMed Central

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.

Roscetto, Emanuela; Angrisano, Tiziana; Costa, Valerio; Casalino, Mariassunta; Forstner, Konrad U.; Sharma, Cynthia M.; Di Nocera, Pier Paolo

2012-01-01

32

The Biocide Triclosan Selects Stenotrophomonas maltophilia Mutants That Overproduce the SmeDEF Multidrug Efflux Pump  

Microsoft Academic Search

Received 28 May 2004\\/Returned for modification 8 August 2004\\/Accepted 7 October 2004 The possibility that triclosan selects Stenotrophomonas maltophilia mutants overexpressing the multidrug resistance pump SmeDEF is analyzed. Five out of 12 triclosan-selected mutants were less susceptible to antibiotics than the wild-type strain and overproduced SmeDEF. Results are discussed in relation to current debates on the potential selection of antibiotic-resistant

Patricia Sanchez; Eduardo Moreno; Jose L. Martinez

2005-01-01

33

Induction of L1 and L2 ?-Lactamases of Stenotrophomonas maltophilia?  

PubMed Central

Isogenic L1 and L2 gene knockout mutants of Stenotrophomonas maltophilia KJ (KJ?L1 and KJ?L2, respectively) were constructed by xylE gene replacement. Induction kinetics of the L1 and L2 genes were evaluated by testing catechol 2,3-dioxygenase activity in the mutants. The results suggested that the induction of the L1 and L2 genes was differentially regulated.

Hu, Rouh-Mei; Huang, Kuang-Jay; Wu, Lii-Tzu; Hsiao, Ying-Ju; Yang, Tsuey-Ching

2008-01-01

34

Stenotrophomonas maltophilia lipopolysaccharide (LPS) and antibiotics: "in vitro" effects on inflammatory mediators.  

PubMed

Stenotrophomonas maltophilia is an emerging pathogen implicated in an increasing number of severe pulmonary infections and nosocomial sepsis. We evaluated the influence of four different antibiotics on the bacterial count and LPS activity found in broth cultures of S. maltophilia. After 4 h ceftazidime (CTZ) decreased live bacteria but increased endotoxin activity, whilst isepamicin (ISE), tobramycin (TB), and polymyxin B (PB) reduced both of them. We also investigated the influence of the above mentioned antibiotics on the ability of S. maltophilia culture filtrates and S. maltophilia LPS, extracted in our laboratory, to stimulate sepsis mediators such as tumor necrosis factor a (TNF-a), interleukin 8 (IL-8), interleukin 10 (IL-10), Nitric Oxide (NO) and as bactericidal/permeability-increasing protein (BPI) in human whole blood. Our results demonstrated that both single polycationic antibiotics and the combination of two molecules are able to kill bacteria and neutralize released S. maltophilia LPS. Combination between beta-lactams and aminoglycosides is often able to reduce the pro-inflammatory effects of S. maltophilia culture filtrates. PMID:15729012

Matera, Giovanni; Barreca, Giorgio Settimo; Puccio, Rossana; Quirino, Angela; Liberto, Maria Carla; De Rosa, Marta; Foca, Alfredo

2004-12-01

35

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 1/2005–12/2010. 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.

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

2012-01-01

36

Characterization of Small-Colony-Variant Stenotrophomonas maltophilia Isolated from the Sputum Specimens of Five Patients with Cystic Fibrosis?  

PubMed Central

Cystic fibrosis (CF) patients are predisposed to chronic respiratory infection by nonfermentative gram-negative bacilli, including Stenotrophomonas maltophilia. S. maltophilia is highly resistant to most antibiotics, with the exception of sulfamethoxazole-trimethoprim (SXT). SXT-resistant S. maltophilia has been reported, but the mechanism of resistance is not well defined. Repeated findings of suspected small-colony-variant (SCV) S. maltophilia isolates from the sputa of five CF patients were confirmed by partial 16S rRNA gene sequencing. The SCV S. maltophilia isolates were the only S. maltophilia isolates in these cultures, and none were clonally related. DNA fingerprint analysis confirmed that once established, the SCV S. maltophilia strains persisted. Nutritional studies of SCV S. maltophilia have suggested auxotrophy in hemin, methionine, and thymidine associated with resistance to multiple antibiotics, including SXT. The phenotypic switch from wild-type to SCV S. maltophilia was reproducible in vitro by exposure to SXT, suggesting that prolonged exposure to antibiotics may select for both the SCV S. maltophilia phenotype and SXT resistance by interference with the dihydrofolate reductase pathway. Recovery of SCV S. maltophilia from the sputum of CF patients has implications for both laboratory testing and patient management.

Anderson, Scott W.; Stapp, Jennifer R.; Burns, Jane L.; Qin, Xuan

2007-01-01

37

Complete Genome Sequence of IME15, the First T7-Like Bacteriophage Lytic to Pan-Antibiotic-Resistant Stenotrophomonas maltophilia  

PubMed Central

T7-like bacteriophages are a class of virulent bacteriophages which have a clearer genetic background and smaller genomes than other phages. In addition, it grows faster and is easier to culture than other phages. At present, the numbers of available T7-like bacteriophage genomes and Stenotrophomonas maltophilia genomes are small, and IME15 is the first T7-like virulent Stenotrophomonas phage whose sequence has been reported. It shows effective lysis of S. maltophilia. Here we announce its complete genome, and major findings from its annotation are described.

Huang, Yong; Fan, Huahao; Pei, Guangqian; Fan, Hang; Zhang, Zhiyi; An, Xiaoping; Mi, Zhiqiang

2012-01-01

38

Specific detection of Stenotrophomonas maltophilia strains in albacore tuna ( Thunnus alalunga) by reverse dot-blot hybridization  

Microsoft Academic Search

A reverse dot-blot DNA\\/DNA hybridization method coupled with a non-radioactive nucleic acid detection system was evaluated for the direct detection of the emerging pathogen Stenotrophomonas maltophilia in albacore tuna, a fish species of high commercial value in Europe and the US. Probes consisting of total genomic DNA of S. maltophilia, when used in dot-blot hybridization assays, differed in a sufficient

Begoña Ben-Gigirey; Juan M. Vieites; Shin H. Kim; Haejung An; Tomás G. Villa; Jorge Barros-Velázquez

2002-01-01

39

Overexpression, Purification, and Characterization of the Cloned Metallo-?-Lactamase L1 from Stenotrophomonas maltophilia  

PubMed Central

The metallo-?-lactamase L1 from Stenotrophomonas maltophilia was cloned, overexpressed, and characterized by spectrometric and biochemical techniques. Results of metal analyses were consistent with the cloned enzyme having 2 mol of tightly bound Zn(II) per monomer. Gel filtration chromatography demonstrated that the cloned enzyme exists as a tightly held tetramer with a molecular mass of ca. 115 kDa, and matrix-assisted laser desorption ionization and time-of-flight mass spectrometry indicated a monomeric molecular mass of 28.8 kDa. Steady-state kinetic studies with a number of diverse penicillin and cephalosporin antibiotics demonstrated that L1 effectively hydrolyzes all tested compounds, with kcat/Km values ranging between 0.002 and 5.5 ?M?1 s?1. These characteristics of the recombinant enzyme are contrasted to those previously reported for metallo-?-lactamases isolated directly from S. maltophilia.

Crowder, Michael W.; Walsh, Timothy R.; Banovic, Linda; Pettit, Margaret; Spencer, James

1998-01-01

40

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

41

[Endocarditis caused by Stenotrophomonas maltophilia: report of a case and review of literature].  

PubMed

We report a case of a 65 year-old woman with late endocarditis of prosthetic aortic valve and paravalvular abscess by Stenotrophomonas maltophilia, which had an acute presentation for the memtionated abscess broken, with fever, bacteremia and congestive heart failure secondary to severity aortic regurgitation. Itacute;s a rare cause of endocarditis with only 22 cases descripted in medical literature, the most of them in parenteral drug addict and as complication of cardiac valve replacement. The literature is reviewed and relate the epidemiology, clinical and prognosis characteristics of this disease, the same as his treatment and prevention. PMID:12848604

López Rodríguez, R; Lado Lado, F L; Sánchez, A; Rodríguez López, I; Gamallo Theodosio, R; Lorenzo Zúñiga, V; Rodríguez-Otero, L

2003-06-01

42

Induction of aromatic ring: cleavage dioxygenases in Stenotrophomonas maltophilia strain KB2 in cometabolic systems  

Microsoft Academic Search

Stenotrophomonas maltophilia KB2 is known to produce different enzymes of dioxygenase family. The aim of our studies was to determine activity of these\\u000a enzymes after induction by benzoic acids in cometabolic systems with nitrophenols. We have shown that under cometabolic conditions\\u000a KB2 strain degraded 0.25–0.4 mM of nitrophenols after 14 days of incubation. Simultaneously degradation of 3 mM of growth\\u000a substrate during 1–3 days

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

2011-01-01

43

Identification of swine influenza A virus and Stenotrophomonas maltophilia co-infection in Chinese pigs  

PubMed Central

Background Influenza virus virulence can be exacerbated by bacterial co-infections. Swine influenza virus (SIV) infection together with some bacteria is found to enhance pathogenicity. Methods SIV-positive samples suspected of containing bacteria were used for bacterial isolation and identification. Antimicrobial susceptibility testing was performed by disc diffusion methods. To investigate the interaction of SIV and the bacteria in vitro, guinea pigs were used as mammalian hosts to determine the effect on viral susceptibility and transmissibility. Differences in viral titers between groups were compared using Student’s t-test. Results During surveillance for SIV in China from 2006 to 2009, seven isolates (24.14%) of 29 influenza A viruses were co-isolated with Stenotrophomonas maltophilia from nasal and tracheal swab samples of pigs. Antimicrobial susceptibility testing showed that the bacteria possessed a high level of resistance towards clinically used antibiotics. To investigate the interaction between these two microorganisms in influencing viral susceptibility and transmission in humans, guinea pigs were used as an infection model. Animals were inoculated with SIV or S. maltophilia alone or co-infected with SIV and S. maltophilia. The results showed that although no transmission among guinea pigs was observed, virus–bacteria co-infections resulted in higher virus titers in nasal washes and trachea and a longer virus shedding period. Conclusions This is the first report of influenza virus co-infection with S. maltophilia in the Chinese swine population. Increased replication of virus by co-infection with multidrug resistant bacteria might increase the infection rate of SIV in humans. The control of S. maltophilia in clinics will contribute to reducing the spread of SIV in pigs and humans.

2012-01-01

44

[Lower respiratory tract infections related to Stenotrophomonas maltophilia and Acinetobacter baumannii].  

PubMed

Stenotrophomonas maltophilia and Acinetobacter baumannii are both non-fermenting ubiquitous Gram-negative bacilli. The incidence of lower respiratory tract infections related to these microorganisms is increasing, especially in intensive care units. Their capacity to acquire resistance against several antimicrobials is challenging for clinicians and microbiologists. Despite their low virulence, these pathogens are responsible for colonization and infection in patients with comorbidities, immunosuppression, and critically ill patients. S. maltophilia and A. baumannii are mainly identified in nosocomial infections: ventilator-associated pneumonia, bacteremia and surgical wound infection. Infections related to these microorganism are associated with high mortality and morbidity. Trimethoprime-sulfamethoxazole and carbapenem are the first line treatment for infections related to S. maltophilia and A. baumannii respectively. However, the increasing rate of resistance against these agents results in difficulties in treating patients with infections related to these pathogens. New antimicrobial agents and further randomized studies are needed to improve the treatment of these infections. Prevention of spared of these multidrug-resistant bacteria is mandatory, including hand-hygiene, environment cleaning, and limited usage of large spectrum antibiotics. PMID:23583504

Baranzelli, A; Wallyn, F; Nseir, S

2013-04-11

45

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.

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

2011-01-01

46

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-Å 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 Å and c = 161.9 Å. 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.

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

2008-01-01

47

Multiple Antibiotic Resistance in Stenotrophomonas maltophilia: Involvement of a Multidrug Efflux System  

PubMed Central

Clinical strains of Stenotrophomonas maltophilia are often highly resistant to multiple antibiotics, although the mechanisms of resistance are generally poorly understood. Multidrug resistant (MDR) strains were readily selected by plating a sensitive reference strain of the organism individually onto a variety of antibiotics, including tetracycline, chloramphenicol, ciprofloxacin, and norfloxacin. Tetracycline-selected MDR strains typically showed cross-resistance to erythromycin and fluoroquinolones and, in some instances, aminoglycosides. MDR mutants selected with the other agents generally displayed resistance to chloramphenicol and fluoroquinolones only, although two MDR strains (e.g., K1385) were also resistant to erythromycin and hypersusceptible to aminoglycosides. Many of the MDR strains expressed either moderate or high levels of a novel outer membrane protein (OMP) of ca. 50 kDa molecular mass, a phenotype typical of MDR strains of Pseudomonas aeruginosa hyperexpressing drug efflux systems. Indeed, the 50-kDa OMP of these S. maltophilia MDR strains reacted with antibody to OprM, the outer membrane component of the MexAB-OprM MDR efflux system of P. aeruginosa. Similarly, a ca. 110-kDa cytoplasmic membrane protein of these MDR strains also reacted with antibody to the MexB component of the P. aeruginosa pump. The outer and cytoplasmic membranes of several clinical S. maltophilia strains also reacted with the anti-OprM and anti-MexB antibodies. N-terminal amino acid sequencing of a cyanogen bromide-generated peptide of the 50-kDa OMP of MDR strain K1385, dubbed SmeM (Stenotrophomonas multidrug efflux), revealed it to be very similar to a number of outer membrane multidrug efflux components of P. aeruginosa and Pseudomonas putida. Deletion of the L1 and L2 ?-lactamase genes confirmed that these enzymes were responsible for the bulk of the ?-lactam resistance of K1385 and its parent. Still, overexpression of the MDR efflux mechanism in an L1- and L2-deficient derivative of K1385 did yield a modest increase in resistance to a few ?-lactams. These data are consistent with the MDR efflux mechanism(s) playing a role in the multidrug resistance of S. maltophilia.

Zhang, Li; Li, Xian-Zhi; Poole, Keith

2000-01-01

48

Draft Genome Sequence of Stenotrophomonas maltophilia Strain EPM1, Found in Association with a Culture of the Human Parasite Giardia duodenalis  

PubMed Central

We report the draft genome sequence of the Stenotrophomonas maltophilia strain EPM1, found in association with a culture of Giardia duodenalis. The draft genome sequence of S. maltophilia strain EPM1, obtained with Roche 454 GS-FLX Titanium technology, is composed of 19 contigs totaling 4,785,869 bp, with a G+C content of 66.37%.

Sassera, Davide; Leardini, Iacopo; Villa, Laura; Comandatore, Francesco; Carta, Claudio; Almeida, Andre; do Ceu Sousa, Maria; Gaiarsa, Stefano; Marone, Piero; Pozio, Edoardo

2013-01-01

49

Differential proteomic analysis of the response of Stenotrophomonas maltophilia to imipenem.  

PubMed

This study represents two different large-scale proteomic experiments analyzing the antibiotic response and the mechanisms of production of ?-lactamases in the nosocomial pathogen Stenotrophomonas maltophilia. Two-dimensional gel electrophoresis on the cytoplasmic protein fraction, together with iTRAQ® differential labeling and 2-D liquid chromatographic separation (2D-LC) MS/MS on the enriched membrane protein fraction, revealed 73 proteins with a change in abundance upon imipenem challenge. These proteins belong to several different functional pathways. We observe an increase in ?-lactamase production as well as in proteins important for their function in the periplasm. The up-regulation of the L1 and L2 ?-lactamases, along with their activator LysR transcriptional factor AmpR, is linked to an increase in proteins responsible for peptidoglycan remodeling and stress response. The interesting identification of an increase in abundance after treatment of the two-component GGDEF signaling protein and an integral membrane sensor signal transduction histidine kinase, indicates that induction of the ?-lactamases is not restricted to the ampR-ampD-ampG pathway. This is the first proteomic study in S. maltophilia upon imipenem stimulation to further unravel the cellular adaptation resulting in ?-lactamase production. PMID:22660730

Van Oudenhove, Laurence; De Vriendt, Kris; Van Beeumen, Jozef; Mercuri, Paola Sandra; Devreese, Bart

2012-06-02

50

Isolation and characterization of a novel strain of Stenotrophomonas maltophilia possessing various dioxygenases for monocyclic hydrocarbon degradation  

PubMed Central

A Gram-negative bacterium, designated as strain KB2, was isolated from activated sludge and was found to utilize different aromatic substrates as sole carbon and energy source. On the basis of morphological and physiochemical characteristics and 16S rRNA gene sequence analysis, the isolated strain KB2 was identified as Stenotrophomonas maltophilia. Strain KB2 is from among different Stenotrophomonas maltophilia strains the first one described as exhibiting the activities of three types of dioxygenases depending on the structure of the inducer. The cells grown on benzoate and catechol showed mainly catechol 1,2-dioxygenase activity. The activity of 2,3-dioxygenase was detected after phenol induction. Protocatechuate 3,4-dioxygenase was found in crude cell extracts of this strain after incubation with 4-hydroxybenzoic acid, protocatechuic acid and vanillic acid. Because of broad spectrum of dioxygenases’ types that Stenotrophomonas maltophilia KB2 can exhibit, this strain appears to be very powerful and useful tool in the biotreatment of wastewaters and in soil decontamination.

Urszula, Guzik; Izabela, Gren; Danuta, Wojcieszynska; Sylwia, Labuzek

2009-01-01

51

Isolation and characterization of a novel strain of Stenotrophomonas maltophilia possessing various dioxygenases for monocyclic hydrocarbon degradation.  

PubMed

A Gram-negative bacterium, designated as strain KB2, was isolated from activated sludge and was found to utilize different aromatic substrates as sole carbon and energy source. On the basis of morphological and physiochemical characteristics and 16S rRNA gene sequence analysis, the isolated strain KB2 was identified as Stenotrophomonas maltophilia. Strain KB2 is from among different Stenotrophomonas maltophilia strains the first one described as exhibiting the activities of three types of dioxygenases depending on the structure of the inducer. The cells grown on benzoate and catechol showed mainly catechol 1,2-dioxygenase activity. The activity of 2,3-dioxygenase was detected after phenol induction. Protocatechuate 3,4-dioxygenase was found in crude cell extracts of this strain after incubation with 4-hydroxybenzoic acid, protocatechuic acid and vanillic acid. Because of broad spectrum of dioxygenases' types that Stenotrophomonas maltophilia KB2 can exhibit, this strain appears to be very powerful and useful tool in the biotreatment of wastewaters and in soil decontamination. PMID:24031359

Urszula, Guzik; Izabela, Gre?; Danuta, Wojcieszy?ska; Sylwia, Labu?ek

2009-06-01

52

Stenotrophomonas maltophilia as a causal agent of pyogranulomatous hepatitis in a buffalo (Bubalus bubalis).  

PubMed

A 7-year-old female buffalo (Bubalus bubalis) from a local herd in Serres, northern Greece, was presented to a private veterinary clinic with a chronic loss of appetite for 15 days. The clinical examination revealed high fever (41.5 degrees C), lethargy, yellow discoloration of skin and mucous membranes, an abdomen that appeared to be empty, hyperactive rumen motility, and tachypnea. A biochemical profile revealed an elevated total bilirubin concentration and hepatic enzyme activities, whereas globulin, creatinine, and glucose concentrations were within the reference intervals. The animal received a 12-day course of treatment with intramuscular administration of ampicillin and corticosteroids. However, no significant clinical improvement was achieved, and the buffalo was euthanized. Gross necropsy lesions included serous atrophy of adipose tissue and hepatomegaly. Microscopic lesions included necrotizing pyogranulomatous hepatitis with thrombosis, hemorrhages, edema, and fibrosis. Small, nonpigmented, bacterial colonies were harvested in pure culture from the liver and were confirmed as Stenotrophomonas maltophilia by polymerase chain reaction. The bacterium was sensitive to ciprofloxacin, enrofloxacin, colistin, polymyxin, trimethoprim/sulfamethaxazole, and chloramphenicol. In contrast, resistance to ticarcillin, piperacillin, imipenem, ceftazidime, amikacin, gentamicin, tobramycin, and tetracycline was displayed. The bacterial strain carried the L1 metallo-beta-lactamase (L1) and tet35 genes, which contribute to high-level resistance to beta-lactams and tetracycline, respectively. Although S. maltophilia is widely believed to be a contaminant, the present report suggests that the isolation, identification, and susceptibility testing of this multidrug-resistant bacterium may be of clinical importance in diagnostic samples. PMID:20807941

Petridou, Evanthia; Filioussis, George; Karavanis, Emmanouel; Kritas, Spyridon K

2010-09-01

53

NagZ-dependent and NagZ-independent mechanisms for ?-lactamase expression in Stenotrophomonas maltophilia.  

PubMed

?-N-Acetylglucosaminidase (NagZ), encoded by the nagZ gene, is a critical enzyme for basal-level ampC derepression (ampC expression in the absence of ?-lactam challenge) in ampD and dacB mutants of Pseudomonas aeruginosa. Three mutants with a phenotype of basal-level L1 and L2 ?-lactamase derepression in Stenotrophomonas maltophilia have been reported, including KJ?DI (ampD(I) mutant), KJ?mrcA (mrcA mutant), and KJ?DI?mrcA (ampD(I) and mrcA double mutant). In this study, nagZ of S. maltophilia was characterized, and its roles in basal-level ?-lactamase derepression, induced ?-lactamase activities, and ?-lactam resistance of KJ?DI, KJ?mrcA, and KJ?DI?mrcA were evaluated. Expression of the nagZ gene was constitutive and not regulated by AmpR, AmpD(I), AmpN, AmpG, PBP1a, and NagZ. Introduction of ?nagZ into KJ?DI nearly abolished basal-level derepressed ?-lactamase activity; conversely, introduction of ?nagZ into KJ?mrcA did not affect it. At least two activator ligands (ALs) are thus considered responsible for ?-lactamase expression in the S. maltophilia system, specifically, the NagZ-dependent (AL1) and NagZ-independent (AL2) ligands responsible for the basal-level derepressed ?-lactamase activities of KJ?DI and KJ?mrcA, respectively. The contributions of AL1 and AL2 to the induced ?-lactamase activities may vary with the types of ?-lactams. nagZ inactivation did not affect aztreonam-, cefoxitin-, and carbenicillin-induced ?-lactamase activities, but it attenuated cefuroxime- and piperacillin-induced ?-lactamase activities. Introduction of ?nagZ into KJ, KJ?DI, KJ?mrcA, and KJ?DI?mrcA did not significantly change the MICs of the ?-lactams tested except that the MICs of cefuroxime and piperacillin moderately decreased in strains KJ?Z and KJ?DI?Z (nagZ mutants). PMID:22252801

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

2012-01-17

54

NagZ-Dependent and NagZ-Independent Mechanisms for ?-Lactamase Expression in Stenotrophomonas maltophilia  

PubMed Central

?-N-Acetylglucosaminidase (NagZ), encoded by the nagZ gene, is a critical enzyme for basal-level ampC derepression (ampC expression in the absence of ?-lactam challenge) in ampD and dacB mutants of Pseudomonas aeruginosa. Three mutants with a phenotype of basal-level L1 and L2 ?-lactamase derepression in Stenotrophomonas maltophilia have been reported, including KJ?DI (ampDI mutant), KJ?mrcA (mrcA mutant), and KJ?DI?mrcA (ampDI and mrcA double mutant). In this study, nagZ of S. maltophilia was characterized, and its roles in basal-level ?-lactamase derepression, induced ?-lactamase activities, and ?-lactam resistance of KJ?DI, KJ?mrcA, and KJ?DI?mrcA were evaluated. Expression of the nagZ gene was constitutive and not regulated by AmpR, AmpDI, AmpN, AmpG, PBP1a, and NagZ. Introduction of ?nagZ into KJ?DI nearly abolished basal-level derepressed ?-lactamase activity; conversely, introduction of ?nagZ into KJ?mrcA did not affect it. At least two activator ligands (ALs) are thus considered responsible for ?-lactamase expression in the S. maltophilia system, specifically, the NagZ-dependent (AL1) and NagZ-independent (AL2) ligands responsible for the basal-level derepressed ?-lactamase activities of KJ?DI and KJ?mrcA, respectively. The contributions of AL1 and AL2 to the induced ?-lactamase activities may vary with the types of ?-lactams. nagZ inactivation did not affect aztreonam-, cefoxitin-, and carbenicillin-induced ?-lactamase activities, but it attenuated cefuroxime- and piperacillin-induced ?-lactamase activities. Introduction of ?nagZ into KJ, KJ?DI, KJ?mrcA, and KJ?DI?mrcA did not significantly change the MICs of the ?-lactams tested except that the MICs of cefuroxime and piperacillin moderately decreased in strains KJ?Z and KJ?DI?Z (nagZ mutants).

Huang, Yi-Wei; Hu, Rouh-Mei; Lin, Cheng-Wen; Chung, Tung-Ching

2012-01-01

55

Chitooligosaccharides are converted to N-acetylglucosamine by N-acetyl-?-hexosaminidase from Stenotrophomonas maltophilia.  

PubMed

The Stenotrophomonas maltophilia k279a (Stm) Hex gene encodes a polypeptide of 785 amino acid residues, with an N-terminal signal peptide. StmHex was cloned without signal peptide and expressed as an 83.6 kDa soluble protein in Escherichia coli BL21 (DE3). Purified StmHex was optimally active at pH 5.0 and 40 °C. The Vmax , Km and kcat /Km for StmHex towards chitin hexamer were 10.55 nkat (mg protein)(-1) , 271 ?M and 0.246 s(-1)  mM(-1) , while the kinetic values with chitobiose were 30.65 nkat (mg protein)(-1) , 2365 ?M and 0.082 s(-1)  mM(-1) , respectively. Hydrolytic activity on chitooligosaccharides indicated that StmHex was an exo-acting enzyme and yielded N-acetyl-d-glucosamine (GlcNAc) as the final product. StmHex hydrolysed chitooligosaccharides (up to hexamer) into GlcNAc within 60 min, suggesting that this enzyme has potential for use in large-scale production of GlcNAc from chitooligosaccharides. PMID:23965017

Katta, Suma; Ankati, Sravani; Podile, Appa Rao

2013-09-13

56

Extracellular serine proteases from Stenotrophomonas maltophilia: Screening, isolation and heterologous expression in E. coli.  

PubMed

A large strain collection comprising antagonistic bacteria was screened for novel detergent proteases. Several strains displayed protease activity on agar plates containing skim milk but were inactive in liquid media. Encapsulation of cells in alginate beads induced protease production. Stenotrophomonas maltophilia emerged as best performer under washing conditions. For identification of wash-active proteases, four extracellular serine proteases called StmPr1, StmPr2, StmPr3 and StmPr4 were cloned. StmPr2 and StmPr4 were sufficiently overexpressed in E. coli. Expression of StmPr1 and StmPr3 resulted in unprocessed, insoluble protein. Truncation of most of the C-terminal domain which has been identified by enzyme modeling succeeded in expression of soluble, active StmPr1 but failed in case of StmPr3. From laundry application tests StmPr2 turned out to be a highly wash-active protease at 45°C. Specific activity of StmPr2 determined with suc-L-Ala-L-Ala-L-Pro-l-Phe-p-nitroanilide as the substrate was 17±2U/mg. In addition we determined the kinetic parameters and cleavage preferences of protease StmPr2. PMID:21983234

Ribitsch, D; Heumann, S; Karl, W; Gerlach, J; Leber, R; Birner-Gruenberger, R; Gruber, K; Eiteljoerg, I; Remler, P; Siegert, P; Lange, J; Maurer, K H; Berg, G; Guebitz, G M; Schwab, H

2011-10-01

57

Antibacterial effects of theaflavin and synergy with epicatechin against clinical isolates of Acinetobacter baumannii and Stenotrophomonas maltophilia.  

PubMed

Stenotrophomonas maltophilia and Acinetobacter baumannii are recognised as important nosocomial pathogens; however, due to their intrinsic resistance to multiple antibiotics, treatment options are limited. Polyphenols from black tea have been shown to possess antibacterial action. In this study, the antibacterial effects of various concentrations of theaflavin as well as combinations of theaflavin and epicatechin were determined using the disk diffusion assay. The results showed strong antibacterial activity of theaflavin against eight clinical isolates of S. maltophilia and A. baumannii. Significant synergy (P?0.05) was also observed between theaflavin and epicatechin against all isolates. Although the mechanisms for this activity and synergy are not well understood, the clinical potential is clear and further research is recommended to determine the modes of action. PMID:21885260

Betts, J W; Kelly, S M; Haswell, S J

2011-08-31

58

Role of Excessive Inflammatory Response to Stenotrophomonas maltophilia Lung Infection in DBA/2 Mice and Implications for Cystic Fibrosis?  

PubMed Central

Stenotrophomonas maltophilia is a pathogen that causes infections mainly in immunocompromised patients. Despite increased S. maltophilia isolation from respiratory specimens of patients with cystic fibrosis (CF), the real contribution of the microorganism to CF pathogenesis still needs to be clarified. The aim of the present study was to evaluate the pathogenic role of S. maltophilia in CF patients by using a model of acute respiratory infection in DBA/2 mice following a single exposure to aerosolized bacteria. The pulmonary bacterial load was stable until day 3 and then decreased significantly from day 3 through day 14, when the bacterial load became undetectable in all infected mice. Infection disseminated in most mice, although at a very low level. Severe effects (swollen lungs, large atelectasis, pleural adhesion, and hemorrhages) of lung pathology were observed on days 3, 7, and 14. The clearance of S. maltophilia observed in DBA/2 mouse lungs was clearly associated with an early and intense bronchial and alveolar inflammatory response, which is mediated primarily by neutrophils. Significantly higher levels of interleukin-1? (IL-1?), IL-6, IL-12, gamma interferon (IFN-?), tumor necrosis factor alpha (TNF-?), GRO?/KC, MCP-1/JE, MCP-5, macrophage inflammatory protein 1? (MIP-1?), MIP-2, and TARC were observed in infected mice on day 1 with respect to controls. Excessive pulmonary infection and inflammation caused systemic effects, manifested by weight loss, and finally caused a high mortality rate. Taken together, our results show that S. maltophilia is not just a bystander in CF patients but has the potential to contribute to the inflammatory process that compromises respiratory function.

Di Bonaventura, Giovanni; Pompilio, Arianna; Zappacosta, Roberta; Petrucci, Francesca; Fiscarelli, Ersilia; Rossi, Cosmo; Piccolomini, Raffaele

2010-01-01

59

The investigation of nematocidal activity in Stenotrophomonas maltophilia G2 and characterization of a novel virulence serine protease.  

PubMed

The Gram-negative bacterium Stenotrophomonas maltophilia G2 was isolated from a soil sample and was found to have high nematotoxic activity against a free-living nematode, Panagrellus redivivus, and a plant-parasitic nematode, Bursaphelenchus xylophilus. The analysis of virulence factors revealed that although the small molecular metabolites participated in nematode killing, the crude extracellular protein extract from the bacterial culture supernatant contributed significantly to its nematocidal activity. An extracellular protease was purified by chromatography, and its effects on degrading purified nematode cuticle and killing living nematodes were confirmed experimentally. Characterization of this purified protease revealed that the application of phenylmethylsulphonyl fluoride, an inhibitor of serine proteases, could completely abolish its proteolytic activity. The results from N-terminal amino acid sequencing showed no similarity with any known serine protease in S. maltophilia, suggesting a novel virulence serine protease was obtained. Our study is the first to show the nematocidal activity of S. maltophilia, and we identified a novel serine protease as an important pathogenicity factor. PMID:19898533

Huang, Xiaowei; Liu, Junwei; Ding, Junmei; He, Qiusheng; Xiong, Rui; Zhang, Keqin

2009-08-01

60

Involvement of Mutation in ampD I, mrcA, and at Least One Additional Gene in ?-Lactamase Hyperproduction in Stenotrophomonas maltophilia.  

PubMed

It has been reported that targeted disruption of ampD I or mrcA causes ?-lactamase hyperproduction in Stenotrophomonas maltophilia. We show here that ?-lactamase-hyperproducing laboratory selected mutants and clinical isolates can have wild-type ampD I and mrcA genes, implicating mutation of at least one additional gene in this phenotype. The involvement of mutations at multiple loci in the activation of ?-lactamase production in S. maltophilia reveals that there are significant deviations from the enterobacterial paradigm of AmpR-mediated control of ?-lactamase induction. We do show, however, that S. maltophilia ampD I can complement a mutation in Escherichia coli ampD. This suggests that an anhydromuropeptide degradation product of peptidoglycan is used to activate AmpR in S. maltophilia, as is also the case in enteric bacteria. PMID:23979761

Talfan, Asmaa; Mounsey, Oliver; Charman, Matthew; Townsend, Eleanor; Avison, Matthew B

2013-08-26

61

Is the prevalence of Stenotrophomonas maltophilia isolation and nosocomial infection increasing in intensive care units?  

Microsoft Academic Search

The study presented here was conducted over a period of 4 years (2001–2004) to investigate changes in the number of S. maltophilia isolates detected per 1,000 patient days and to look at the incidence density of nosocomial infections caused by S. maltophilia. The analysis was based on data provided by 34 German intensive care units participating continuously in the national project

E. Meyer; F. Schwab; P. Gastmeier; H. Rüden; F. D. Daschner

2006-01-01

62

Predictive analysis of transmissible quinolone resistance indicates Stenotrophomonas maltophilia as a potential source of a novel family of Qnr determinants  

PubMed Central

Background Predicting antibiotic resistance before it emerges at clinical settings constitutes a novel approach for preventing and fighting resistance of bacterial pathogens. To analyse the possibility that novel plasmid-encoded quinolone resistance determinants (Qnr) can emerge and disseminate among bacterial pathogens, we searched the presence of those elements in nearly 1000 bacterial genomes and metagenomes. Results We have found a number of novel potential qnr genes in the chromosomes of aquatic bacteria and in metagenomes from marine organisms. Functional studies of the Stenotrophomonas maltophilia Smqnr gene show that plasmid-encoded SmQnr confers quinolone resistance upon its expression in a heterologous host. Conclusion Altogether, the data presented in our work support the notion that predictive studies on antibiotic resistance are feasible, using currently available information on bacterial genomes and with the aid of bioinformatic and functional tools. Our results confirm that aquatic bacteria can be the origin of plasmid-encoded Qnr, and highlight the potential role of S. maltophilia as a source of novel Qnr determinants.

Sanchez, Maria B; Hernandez, Alvaro; Rodriguez-Martinez, Jose M; Martinez-Martinez, Luis; Martinez, Jose L

2008-01-01

63

Cell surface properties and fatty acids composition of Stenotrophomonas maltophilia under the influence of hydrophobic compounds and surfactants.  

PubMed

Surface properties of newly isolated Stenotrophomonas maltophilia strain 6 were tested. The bacteria were stored in two different ways to determine the influence of hydrocarbons and surfactants on surface and enzymatic characteristics of the isolated strain. The influence of surface active agents, natural and synthetic, on membrane's lipid composition and cell surface hydrophobicity (CSH) was investigated. Our results indicate that long-term contact with diesel oil as a hydrophobic sole carbon source leads to the increased enzymatic activity of S. maltophilia strain 6 as well as to modification of fatty acids profiles and its facility to adhere to hydrophobic compounds. Among surfactants there were saponins and Triton X-100 which changed the composition of fatty acids the most, increasing the amount of branched acids. The comparison of fatty acid profiles with CSH of systems with diesel oil, rhamnolipids, saponins and Triton X-100 points out that the growing amount of hydroxy fatty acids corresponds to lower hydrophobicity. Moreover, CSH is a dynamic parameter which can change during cultivation of microorganisms. PMID:22989923

Kaczorek, Ewa; Sa?ek, Karina; Guzik, Urszula; Dudzi?ska-Bajorek, Beata

2012-09-16

64

Influence of metal ions on bioremediation activity of protocatechuate 3,4-dioxygenase from Stenotrophomonas maltophilia KB2.  

PubMed

The aim of this paper was to describe the effect of various metal ions on the activity of protocatechuate 3,4-dioxygenase from Stenotrophomonas maltophilia KB2. We also compared activity of different dioxygenases isolated from this strain, in the presence of metal ions, after induction by various aromatic compounds. S. maltophilia KB2 degraded 13 mM 3,4-dihydroxybenzoate, 10 mM benzoic acid and 12 mM phenol within 24 h of incubation. In the presence of dihydroxybenzoate and benzoate, the activity of protocatechuate 3,4-dioxygenase and catechol 1,2-dioxygenase was observed. Although Fe(3+), Cu(2+), Zn(2+), Co(2+), Al(3+), Cd(2+), Ni(2+) and Mn(2+) ions caused 20-80 % inhibition of protocatechuate 3,4-dioxygenase activity, the above-mentioned metal ions (with the exception of Ni(2+)) inhibited catechol 1,2-dioxygenase to a lesser extent or even activate the enzyme. Retaining activity of at least one of three dioxygenases from strain KB2 in the presence of metal ions makes it an ideal bacterium for bioremediation of contaminated areas. PMID:23014843

Guzik, Urszula; Hupert-Kocurek, Katarzyna; Sa?ek, Karina; Wojcieszy?ska, Danuta

2012-09-27

65

Activity of levofloxacin and ciprofloxacin on biofilms and planktonic cells of Stenotrophomonas maltophilia isolates from patients with device-associated infections  

Microsoft Academic Search

The aim of this work was to compare the in vitro effects of levofloxacin and ciprofloxacin on pre-formed biofilms and planktonic populations of Stenotrophomonas maltophilia isolates from device-associated infections recovered over the period 2004–2008 at a university hospital in Argentina. For planktonic susceptibility studies, the minimum inhibitory concentrations (MICs) of fluoroquinolones were determined by the broth microdilution method. From the

B. Passerini de Rossi; C. García; M. Calenda; C. Vay; M. Franco

2009-01-01

66

Stenotrophomonas maltophilia D457R Contains a Cluster of Genes from Gram-Positive Bacteria Involved in Antibiotic and Heavy Metal Resistance  

Microsoft Academic Search

A cluster of genes involved in antibiotic and heavy metal resistance has been characterized from a clinical isolate of the gram-negative bacterium Stenotrophomonas maltophilia. These genes include a macrolide phos- photransferase (mphBM) and a cadmium efflux determinant (cadA), together with the gene cadC coding for its transcriptional regulator. The cadC cadA region is flanked by a truncated IS257 sequence and

ANA ALONSO; PATRICIA SANCHEZ; JOSEL. MARTINEZ

2000-01-01

67

Activities of Ciprofloxacin and Moxifloxacin against Stenotrophomonas maltophilia and Emergence of Resistant Mutants in an In Vitro Pharmacokinetic-Pharmacodynamic Model  

Microsoft Academic Search

A two-compartment in vitro pharmacokinetic-pharmacodynamic model, with full computer-controlled de- vices, was used to accurately simulate human plasma pharmacokinetic profiles after multidose oral regimens of ciprofloxacin (750 mg every 12 h) and moxifloxacin (400 mg every 24 h) during 48 h. Pharmacodynamics of these drugs was investigated against three quinolone-susceptible strains of Stenotrophomonas maltophilia (MICs of ciprofloxacin and moxifloxacin of

Boubakar B. Ba; Hala Feghali; Corinne Arpin; Marie-Claude Saux; Claudine Quentin

2004-01-01

68

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

69

AmpDI is involved in expression of the chromosomal L1 and L2 beta-lactamases of Stenotrophomonas maltophilia.  

PubMed

Two ampD homologues, ampD(I) and ampD(II), of Stenotrophomonas maltophilia have been cloned and analyzed. Comparative genomic analysis revealed that the genomic context of the ampD(II) genes is quite different, whereas that of the ampD(I) genes is more conserved in S. maltophilia strains. The ampD system of S. maltophilia is distinct from that of the Enterobacteriaceae and Pseudomonas aeruginosa in three respects. (i) AmpD(I) of S. maltophilia is not encoded in an ampDE operon, in contrast to what happens in the Enterobacteriaceae and P. aeruginosa. (ii) The AmpD systems of the Enterobacteriaceae and P. aeruginosa are generally involved in the regulation of ampR-linked ampC gene expression, while AmpD(I) of S. maltophilia is responsible for the regulation of two intrinsic beta-lactamase genes, of which the L2 gene, but not the L1 gene, is linked to ampR. (iii) S. maltophilia exhibits a one-step L1 and L2 gene derepression model involving ampD(I), distinct from the two- or three-step derepression of the Enterobacteriaceae and P. aeruginosa. Moreover, the ampD(I) and ampD(II) genes are constitutively expressed and not regulated by the inducer and AmpR protein, and the expression of ampD(II) is weaker than that of ampD(I). Finally, AmpD(II) is not associated with the derepression of beta-lactamases, and its role in S. maltophilia remains unclear. PMID:19414581

Yang, Tsuey-Ching; Huang, Yi-Wei; Hu, Rouh-Mei; Huang, Shao-Cheng; Lin, Yu-Tzu

2009-05-04

70

Cold-active extracellular alkaline protease from an alkaliphilic Stenotrophomonas maltophilia: production of enzyme and its industrial applications.  

PubMed

A novel psychro-tolerant bacterium Stenotrophomonas maltophilia (MTCC 7528) with an ability to produce extracellular, cold-active, alkaline, and detergent-stable protease was isolated from soil samples obtained from Gangotri glacier, Western Himalaya, India. The culture conditions for higher protease production were optimized with respect to incubation time, agitation, substrate, pH, and temperature. Maximum protease production of 56.2 U x mL(-1) was achieved in the medium at 20 degrees C and pH 9.0 after 120 h incubation. The protease was partially purified by ion-exchange chromatography and approximately 55-fold purification was achieved. The purified enzyme was a 75 kDa protease with maximum activity and stability at pH 10 and 20 degrees C. The activity of enzyme is stimulated by Mn2+ and inhibited completely by metalloprotease inhibitors, indicating that it is a metalloprotease. The protease showed excellent stability and compatibility with commercial detergents and exhibited high efficiency for the removal of different types of protein-containing stains at low temperature. The wash performance analysis of blood and grass stains on cotton fabric showed an increase in reflectance by 26% and 23%, respectively, after treatment with enzyme in comparison to detergent only. These results indicate that it may be a potential component to use as a detergent additive for cold washing and in environmental bioremediation in cold regions. PMID:19940938

Kuddus, Mohammed; Ramteke, Pramod W

2009-11-01

71

Site Selective Binding of Zn(ll) ot Metallo-b-Lactamase L1 from Stenotrophomonas Maltophilia  

SciTech Connect

Extended X-ray absorption fine structure studies of the metallo-{beta}-lactamase L1 from Stenotrophomonas maltophilia containing 1 and 2 equiv of Zn(II) and containing 2 equiv of Zn(II) plus hydrolyzed nitrocefin are presented. The data indicate that the first, catalytically dominant metal ion is bound by L1 at the consensus Zn1 site. The data further suggest that binding of the first metal helps preorganize the ligands for binding of the second metal ion. The di-Zn enzyme displays a well-defined metal-metal interaction at 3.42 Angstroms. Reaction with the {beta}-lactam antibiotic nitrocefin results in a product-bound species, in which the ring-opened lactam rotates in the active site to present the S1 sulfur atom of nitrocefin to one of the metal ions for coordination. The product bridges the two metal ions, with a concomitant lengthening of the Zn-Zn interaction to 3.62 Angstroms.

Costello,A.; Periyannan, G.; Yang, K.; Crowder, M.; Tierney, D.

2006-01-01

72

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.

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

2007-01-01

73

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 UV–visible, 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.

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

2013-01-01

74

Probing substrate binding to Metallo-?-Lactamase L1 from Stenotrophomonas maltophilia by using site-directed mutagenesis  

PubMed Central

Background The metallo-?-lactamases are Zn(II)-containing enzymes that hydrolyze the ?-lactam bond in penicillins, cephalosporins, and carbapenems and are involved in bacterial antibiotic resistance. There are at least 20 distinct organisms that produce a metallo-?-lactamase, and these enzymes have been extensively studied using X-ray crystallographic, computational, kinetic, and inhibition studies; however, much is still unknown about how substrates bind and the catalytic mechanism. In an effort to probe substrate binding to metallo-?-lactamase L1 from Stenotrophomonas maltophilia, nine site-directed mutants of L1 were prepared and characterized using metal analyses, CD spectroscopy, and pre-steady state and steady state kinetics. Results Site-directed mutations were generated of amino acids previously predicted to be important in substrate binding. Steady-state kinetic studies using the mutant enzymes and 9 different substrates demonstrated varying Km and kcat values for the different enzymes and substrates and that no direct correlation between Km and the effect of the mutation on substrate binding could be drawn. Stopped-flow fluorescence studies using nitrocefin as the substrate showed that only the S224D and Y228A mutants exhibited weaker nitrocefin binding. Conclusions The data presented herein indicate that Ser224, Ile164, Phe158, Tyr228, and Asn233 are not essential for tight binding of substrate to metallo-?-lactamase L1. The results in this work also show that Km values are not reliable for showing substrate binding, and there is no correlation between substrate binding and the amount of reaction intermediate formed during the reaction. This work represents the first experimental testing of one of the computational models of the metallo-?-lactamases.

Carenbauer, Anne L; Garrity, James D; Periyannan, Gopal; Yates, Robert B; Crowder, Michael W

2002-01-01

75

Modification of surface and enzymatic properties of Achromobacter denitrificans and Stenotrophomonas maltophilia in association with diesel oil biodegradation enhanced with alkyl polyglucosides.  

PubMed

The article concerns the influence of selected alkyl polyglucosides on biodegradation, cell surface and enzymatic properties of Stenotrophomonas maltophilia and Achromobacter denitrificans. The biodegradation of diesel oil depends on several factors including type and the amount of surfactant as well as bacterial genera used in the process. Nevertheless, a careful selection of these variables must be made as some bacterial strains prefer to use surfactants as their carbon source. This leads to the lowered biodegradation of diesel oil as can be observed for the tested S. maltophilia strain. Alkyl polyglucosides influenced the cell surface properties of both of the tested strains in slightly different ways. Especially for A. denitrificans, for which the hydrophobicity increased with concentration of both - Lutensol GD 70 and Glucopon 215 in diesel oil-surfactant systems. Moreover, judging by the efficiency of biodegradation, the most effective process was observed in the presence of Lutensol GD 70 (240 and 360mgL(-1)) with biodegradation rising from 32% (without surfactant) to 68%. No such relation was observed for S. maltophilia. PMID:23777790

Sa?ek, Karina; Zgo?a-Grze?kowiak, Agnieszka; Kaczorek, Ewa

2013-05-22

76

In vitro antibacterial and antibiofilm activities of chlorogenic acid against clinical isolates of Stenotrophomonas maltophilia including the trimethoprim/sulfamethoxazole resistant strain.  

PubMed

The in vitro antibacterial and antibiofilm activity of chlorogenic acid against clinical isolates of Stenotrophomonas maltophilia was investigated through disk diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), time-kill and biofilm assays. A total of 9 clinical S. maltophilia isolates including one isolate resistant to trimethoprim/sulfamethoxazole (TMP/SMX) were tested. The inhibition zone sizes for the isolates ranged from 17 to 29?mm, while the MIC and MBC values ranged from 8 to 16? ?g mL(-1) and 16 to 32? ?g mL(-1). Chlorogenic acid appeared to be strongly bactericidal at 4x MIC, with a 2-log reduction in viable bacteria at 10?h. In vitro antibiofilm testing showed a 4-fold reduction in biofilm viability at 4x MIC compared to 1x MIC values (0.085 < 0.397 A 490?nm) of chlorogenic acid. The data from this study support the notion that the chlorogenic acid has promising in vitro antibacterial and antibiofilm activities against S. maltophilia. PMID:23509719

Karunanidhi, Arunkumar; Thomas, Renjan; van Belkum, Alex; Neela, Vasanthakumari

2012-12-20

77

In Vitro Antibacterial and Antibiofilm Activities of Chlorogenic Acid against Clinical Isolates of Stenotrophomonas maltophilia including the Trimethoprim/Sulfamethoxazole Resistant Strain  

PubMed Central

The in vitro antibacterial and antibiofilm activity of chlorogenic acid against clinical isolates of Stenotrophomonas maltophilia was investigated through disk diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), time-kill and biofilm assays. A total of 9 clinical S. maltophilia isolates including one isolate resistant to trimethoprim/sulfamethoxazole (TMP/SMX) were tested. The inhibition zone sizes for the isolates ranged from 17 to 29?mm, while the MIC and MBC values ranged from 8 to 16??g mL?1 and 16 to 32??g mL?1. Chlorogenic acid appeared to be strongly bactericidal at 4x MIC, with a 2-log reduction in viable bacteria at 10?h. In vitro antibiofilm testing showed a 4-fold reduction in biofilm viability at 4x MIC compared to 1x MIC values (0.085 < 0.397 A 490?nm) of chlorogenic acid. The data from this study support the notion that the chlorogenic acid has promising in vitro antibacterial and antibiofilm activities against S. maltophilia.

Karunanidhi, Arunkumar; Thomas, Renjan; van Belkum, Alex; Neela, Vasanthakumari

2013-01-01

78

In vitro efficacy of copper and silver ions in eradicating Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Acinetobacter baumannii: implications for on-site disinfection for hospital infection control.  

PubMed

Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Acinetobacter baumannii are major opportunistic waterborne pathogens causing hospital-acquired infections. Copper-silver ionization has been shown to be effective in controlling Legionella colonization in hospital water systems. The objective was to determine the efficacy of copper and silver ions alone and in combination in eradicating P. aeruginosa, S. maltophilia and A. baumannii at the concentration applied to Legionella control. Kill curve experiments and mathematical modeling were conducted at copper and silver ion concentrations of 0.1, 0.2, 0.4, 0.8 and 0.01, 0.02, 0.04, 0.08 mg/L, respectively. The combinations of copper and silver ions were tested at concentrations of 0.2/0.02 and 0.4/0.04 mg/L, respectively. Initial organism concentration was ca. of 3 x 10(6)cfu/mL, and viability of the test organisms was assessed at predetermined time intervals. Samples (0.1 mL) withdrawn were mixed with 10 microL neutralizer solution immediately, serially diluted and plated in duplicate onto blood agar plates. The culture plates were incubated for 48 h at 37 degrees C and enumerated for the cfu (detection limit 10 cfu/mL). The results showed all copper ion concentrations tested (0.1-0.8 mg/L) achieved more than 99.999% reduction of P. aeruginosa which appears to be more susceptible to copper ions than S. maltophilia and A. baumannii. Silver ions concentration of 0.08 mg/L achieved more than 99.999% reduction of P. aeruginosa, S. maltophilia and A. baumannii in 6, 12 and 96 h, respectively. Combination of copper and silver ions exhibited a synergistic effect against P. aeruginosa and A. baumannii while the combination exhibited an antagonistic effect against S. maltophilia. Ionization may have a potential to eradicate P. aeruginosa, S. maltophilia and A. baumannii from hospital water systems. PMID:17655912

Huang, Hsin-I; Shih, Hsiu-Yun; Lee, Chien-Ming; Yang, Thomas C; Lay, Jiunn-Jyi; Lin, Yusen E

2007-07-12

79

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 36°C. 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.

Mukherjee, Piyali; Roy, Pranab

2013-01-01

80

Structure of Stenotrophomonas maltophilia FeoA complexed with zinc: a unique prokaryotic SH3-domain protein that possibly acts as a bacterial ferrous iron-transport activating factor.  

PubMed

Iron is vital to the majority of prokaryotes, with ferrous iron believed to be the preferred form for iron uptake owing to its much better solubility. The major route for bacterial ferrous iron uptake is found to be via an Feo (ferrous iron-transport) system comprising the three proteins FeoA, FeoB and FeoC. Although the structure and function of FeoB have received much attention recently, the roles played by FeoA and FeoC have been little investigated to date. Here, the tertiary structure of FeoA from Stenotrophomonas maltophilia (Sm), a vital opportunistic pathogen in immunodepressed hosts, is reported. The crystal structure of SmFeoA has been determined to a resolution of 1.7 A using an Se single-wavelength anomalous dispersion (Se-SAD) approach. Although SmFeoA bears low sequence identity to eukaryotic proteins, its structure is found to adopt a eukaryotic SH3-domain-like fold. It also bears weak similarity to the C-terminal SH3 domain of bacterial DtxR (diphtheria toxin regulator), with some unique characteristics. Intriguingly, SmFeoA is found to adopt a unique dimer cross-linked by two zinc ions and six anions (chloride ions). Since FeoB has been found to contain a G-protein-like domain with low GTPase activity, FeoA may interact with FeoB through the SH3-G-protein domain interaction to act as a ferrous iron-transport activating factor. PMID:20516589

Su, Yi Che; Chin, Ko Hsin; Hung, Hui Chih; Shen, Gwan Han; Wang, Andrew H J; Chou, Shan Ho

2010-05-25

81

Occurrence and antagonistic potential of Stenotrophomonas strains isolated from deep-sea invertebrates.  

PubMed

Stenotrophomonas maltophilia is known to be of significance as opportunistic pathogen as well as a source of biocontrol and bioremediation activities. S. maltophilia strains have been isolated from rhizospheres, soil, clinical material, aquatic habitats, but little is known about Stenotrophomonas strains recovered from marine environments. During a survey of the biodiversity of Pseudomonas-like bacteria associated with deep-sea invertebrates six Stenotrophomonas strains were isolated from sponge, sea urchin, and ophiura specimens collected from differing Pacific areas, including the Philippine Sea, the Fiji Sea and the Bering Sea. 16S rRNA gene sequence analysis confirmed an assignment of marine isolates to the genus Stenotrophomonas as it placed four strains into the S. maltophilia CIP 60.77T cluster and two related to the S. rhizophila DSM 14405T. Together with a number of common characteristics typical of S. maltophilia and S. rhizophila marine isolates exhibited differences in pigmentation, a NaCl tolerance, a range of temperatures, which supported their growth, substrate utilization pattern, and antibiotics resistance. Strains displayed hemolytic and remarkable inhibitory activity against a number of fungal cultures and Gram-positive microorganisms, but very weak or none against Candida albicans. This is the first report on isolation, taxonomic characterization and antimicrobial activity of Stenotrophomonas strains isolated from deep-sea invertebrates. PMID:18034228

Romanenko, Lyudmila A; Uchino, Masataka; Tanaka, Naoto; Frolova, Galina M; Slinkina, Natalia N; Mikhailov, Valery V

2007-11-21

82

Stenotrophomonas afiicana sp. nov., an Opportunistic Human Pathogen in Africa  

Microsoft Academic Search

A gram-negative bacterium was isolated from a cerebrospinal fluid sample from an HIV-seropositive Rwandan refugee with primary meningoencephalitis. This Marseille-Goma sample B isolate, strain MGBT (T = type strain), was found to exhibit evolutionary homology with Stenotrophomonas maltophilia, as deter- mined by a 16s rRNA gene sequence analysis, and this finding was reflected by similar phenotypic traits. MGBT could, however,

M. DRANCOURT; C. BOLLET; D. RAOULT

83

Delineation of Stenotrophomonas spp. by multi-locus sequence analysis and MALDI-TOF mass spectrometry  

Microsoft Academic Search

The genus Stenotrophomonas is genetically and phenotypically heterogeneous. Of the nine species now accepted, only S. maltophilia is of clinical importance. Based on DNA-sequences of seven house keeping genes, it encompasses genogroups of DNA-similarity below 97% that predominantly comprise strains of environmental origin. Therefore, in order to unravel the uneven distribution of environmental isolates within genogroups and reveal genetic relationships

Zinaida Vasileuskaya-Schulz; Sabine Kaiser; Thomas Maier; Markus Kostrzewa; Daniel Jonas

2011-01-01

84

PCR-based rapid genotyping of Stenotrophomonas maltophilia isolates  

Microsoft Academic Search

BACKGROUND: All bacterial genomes contain repetitive sequences which are members of specific DNA families. Such repeats may occur as single units, or found clustered in multiple copies in a head-to-tail configuration at specific loci. The number of clustered units per locus is a strain-defining parameter. Assessing the length variability of clusters of repeats is a versatile typing methodology known as

Emanuela Roscetto; Francesco Rocco; M Stella Carlomagno; Mariassunta Casalino; Bianca Colonna; Raffaele Zarrilli; Pier Paolo Di Nocera

2008-01-01

85

Screening for endophytic nitrogen-fixing bacteria in Brazilian sugar cane varieties used in organic farming and description of Stenotrophomonas pavanii sp. nov.  

PubMed

A Gram-negative, rod-shaped, non-spore-forming and nitrogen-fixing bacterium, designated ICB 89(T), was isolated from stems of a Brazilian sugar cane variety widely used in organic farming. 16S rRNA gene sequence analysis revealed that strain ICB 89(T) belonged to the genus Stenotrophomonas and was most closely related to Stenotrophomonas maltophilia LMG 958(T), Stenotrophomonas rhizophila LMG 22075(T), Stenotrophomonas nitritireducens L2(T), [Pseudomonas] geniculata ATCC 19374(T), [Pseudomonas] hibiscicola ATCC 19867(T) and [Pseudomonas] beteli ATCC 19861(T). DNA-DNA hybridization together with chemotaxonomic data and biochemical characteristics allowed the differentiation of strain ICB 89(T) from its nearest phylogenetic neighbours. Therefore, strain ICB 89(T) represents a novel species, for which the name Stenotrophomonas pavanii sp. nov. is proposed. The type strain is ICB 89(T) (?=?CBMAI 564(T) ?=?LMG 25348(T)). PMID:20495025

Ramos, Patrícia L; Van Trappen, Stefanie; Thompson, Fabiano L; Rocha, Rafael C S; Barbosa, Heloiza R; De Vos, Paul; Moreira-Filho, Carlos A

2010-05-21

86

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

87

Stenotrophomonas and Lysobacter: ubiquitous plant-associated gamma-proteobacteria of developing significance in applied microbiology.  

PubMed

The exploration of new source materials and the use of alternative isolation and identification methods have led to rapid expansion in the knowledge of diversity; in Lysobacter, 11 new species having been described since 2005, and in Stenotrophomonas with six new species since 2000. The new species of Lysobacter, isolated by dilution and direct plating on standard media, differ in several key phenotypic properties from those obtained by enrichment on complex polysaccharides in the original description of the genus. Revision of the definition of the genus will be required. Both culture-dependent and culture-independent methods to assess community structure, in a variety of host and nonhost environments, have established that some species of Lysobacter are a dominant component of the microflora, where previously their presence had not been suspected. Culture-independent studies have generally not added new information on the occurrence and distribution of Stenotrophomonas maltophilia and other members of the genus, which are readily isolated on standard media from source materials. Lysobacter enzymogenes and Sten. maltophilia produce similar antibiotics and share some enzyme activities which, subject to safety considerations, may make them attractive candidates for use in biological control of plant diseases and of nematodes. PMID:19702860

Hayward, A C; Fegan, N; Fegan, M; Stirling, G R

2009-07-13

88

[Environmental factors affecting the succinic acid production by Actinobacillus succinogenes CGMCC 1593].  

PubMed

Actinobacillus succinogenes is a promising candidate for the production of bio-based succinic acid. Previously, we isolated a succinic acid-producing strain Actinobacillus succinogenes CGMCC 1593 from bovine rumen. In this paper, the influence of the environmental factors such as gas phase, pH, ORP, on succinic acid production by A. succinogenes CGMCC 1593 was studied. The results showed that CO2 was the optimum gas phase for anaerobic fermentation ofA. succinogenes CGMCC 1593 as well as one of the substrate for the succinic acid synthesis. Using MgCO3 as a pH regulator, the pH was maintained within 7.1-6.2 during the anaerobic fermentation for the cell growth and acid production of A. succinogenes CGMCC 1593. Our results showed that low initial ORP was disadvantageous for the growth of A. succinogenes CGMCC 1593 and an ORP of -270 mV was demonstrated to be beneficial to the succinic acid production. By adding Na2S.9H2O to decrease ORP to -270 mV at the end of exponential growth phase in batch culture of A. succinogenes CGMCC 1593, the succinic acid concentration reached 37 g/L and the yield of succinic acid was 129% at 48 h. This work might provide valuable information for further optimization of succinic acid fermentation by A. succinogenes CGMCC 1593. PMID:18807991

Zheng, Pu; Zhou, Wei; Ni, Ye; Jiang, Min; Wei, Ping; Sun, Zhihao

2008-06-01

89

Optimization of Conditions for the Biotransformation of 5-Cyanovaleramide from Adiponitrile by Rhodococcus ruber CGMCC 3090  

Microsoft Academic Search

Abstract-Adiponitrile was regioselectively converted to 5-cyanovaleramide as the single product using resting cells of Rhodococcus ruber CGMCC3090. In this research, the reaction characteristics of regioselective biotransformation of adiponitrile to 5-cyanovaleramide using Rhodococcus ruber CGMCC3090 was studied, and the reaction conditions were optimized. As a result, the optimum reaction temperature and pH were 30°C and 7.5, respectively. The deactivation energy of

Xiao-Dan Li; Min Wang; Yu Zheng; Jian-mei Luo; Hua Sun

2010-01-01

90

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

91

Predictive analysis of transmissible quinolone resistance indicates Stenotrophomonas maltophilia as a potential source of a novel family of Qnr determinants  

Microsoft Academic Search

BACKGROUND: Predicting antibiotic resistance before it emerges at clinical settings constitutes a novel approach for preventing and fighting resistance of bacterial pathogens. To analyse the possibility that novel plasmid-encoded quinolone resistance determinants (Qnr) can emerge and disseminate among bacterial pathogens, we searched the presence of those elements in nearly 1000 bacterial genomes and metagenomes. RESULTS: We have found a number

María B Sánchez; Alvaro Hernández; José M Rodríguez-Martínez; Luis Martínez-Martínez; José L Martínez

2008-01-01

92

Probing substrate binding to Metallo-?-Lactamase L1 from Stenotrophomonas maltophilia by using site-directed mutagenesis  

Microsoft Academic Search

BACKGROUND: The metallo-?-lactamases are Zn(II)-containing enzymes that hydrolyze the ?-lactam bond in penicillins, cephalosporins, and carbapenems and are involved in bacterial antibiotic resistance. There are at least 20 distinct organisms that produce a metallo-?-lactamase, and these enzymes have been extensively studied using X-ray crystallographic, computational, kinetic, and inhibition studies; however, much is still unknown about how substrates bind and the

Anne L Carenbauer; James D Garrity; Gopal Periyannan; Robert B Yates; Michael W Crowder

2002-01-01

93

Production of poly(3-hydroxybutyrate- co -3-hydroxyhexanoate) with flexible 3-hydroxyhexanoate content in Aeromonas hydrophila CGMCC 0911  

Microsoft Academic Search

Aeromonas hydrophila CGMCC 0911 isolated from lake water was found to be able to synthesize a polyhydroxyalkanoate (PHA) copolymer (PHBHHx) consisting of 3-hydroxybutyrate (HB) and 4–6 mol% 3-hydroxyhexanoate (HHx). The wild-type bacterium accumulated 49% PHBHHx containing 6 mol% HHx in terms of cell dry weight (CDW) when grown on lauric acid for 48 h. When A. hydrophila CGMCC 0911 expressed the Acyl-CoA dehydrogenase

X. Y. Lu; Q. Wu; G. Q. Chen

2004-01-01

94

Acrylamide biodegradation ability and plant growth-promoting properties of Variovorax boronicumulans CGMCC 4969.  

PubMed

Species of the genus Variovorax are often isolated from nitrile or amide-containing organic compound-contaminated soil. However, there have been few biological characterizations of Variovorax and their contaminant-degrading enzymes. Previously, we reported a new soil isolate, Variovorax boronicumulans CGMCC 4969, and its nitrile hydratase that transforms the neonicotinoid insecticide thiacloprid into an amide metabolite. In this study, we showed that CGMCC 4969 is able to degrade acrylamide, a neurotoxicant and carcinogen in animals, during cell growth in a mineral salt medium as well as in its resting state. Resting cells rapidly hydrolyzed 600 mg/L acrylamide to acrylic acid with a half-life of 2.5 min. In in vitro tests, CGMCC 4969 showed plant growth-promoting properties; it produced a siderophore, ammonia, hydrogen cyanide, and the phytohormone salicylic acid. Interestingly, in soil inoculated with this strain, 200 mg/L acrylamide was completely degraded in 4 days. Gene cloning and overexpression in the Escherichia coli strain Rosetta (DE3) pLysS resulted in the production of an aliphatic amidase of 345 amino acids that hydrolyzed acrylamide into acrylic acid. The amidase contained a conserved catalytic triad, Glu59, Lys 134, and Cys166, and an "MRHGDISSS" amino acid sequence at the N-terminal region. Variovorax boronicumulans CGMCC 4969, which is able to use acrylamide for cell growth and rapidly degrade acrylamide in soil, shows promising plant growth-promoting properties. As such, it has the potential to be developed into an effective Bioaugmentation strategy to promote growth of field crops in acrylamide-contaminated soil. PMID:23546990

Liu, Zhong-Hua; Cao, Yu-Min; Zhou, Qian-Wen; Guo, Kun; Ge, Feng; Hou, Jun-Yi; Hu, Si-Yi; Yuan, Sheng; Dai, Yi-Jun

2013-04-02

95

Biosynthetic pathway of sugar nucleotides essential for welan gum production in Alcaligenes sp. CGMCC2428  

Microsoft Academic Search

Welan gum is a microbial polysaccharide produced by Alcaligenes sp. CGMCC2428 that has d-glucose, d-glucuronic acid, d-glucose, and l-rhamnose as the main structural unit. The biosynthetic pathway of sugar nucleotides essential for producing welan gum in\\u000a this strain was established in the following ways: (1) the detection of the presence of several intermediates and key enzymes;\\u000a (2) the analysis of

Hui Li; Hong Xu; Hao Xu; Sha Li; Ping-Kai Ouyang

2010-01-01

96

Advances in the bioconversion mechanism of lovastatin to wuxistatin by Amycolatopsis sp. CGMCC 1149.  

PubMed

Wuxistatin, a novel statin and more potent than lovastatin, was converted from lovastatin by Amycolatopsis sp. (CGMCC 1149). Product I, an intermediate product, was found in the fermentation broth, and the structure analysis showed that product I had an additional hydroxyl group at the methyl group attached to C3 compared to lovastatin, which indicates that product I is one isomer of wuxistatin. Isotope tracing experiment proved that hydroxyl group of wuxistatin was provided by product I and the reaction from product I to wuxistatin was an intramolecular transfer. Hydroxylation reaction established in a cell-free system could be inhibited by CO and enhanced by ATP, Fe(2+), and ascorbic acid, which were consistent with the presumption that the hydroxylase was an induced cytochrome P450. Study on proteomics of Amycolatopsis sp. CGMCC 1149 suggested that three identified proteins, including integral membrane protein, Fe-S oxidoreductase, and GTP-binding protein YchF, were induced by lovastatin and required during hydroxylation reaction. In conclusion, bioconversion mechanism of wuxistatin by Amycolatopsis sp. CGMCC 1149 was proposed: lovastatin is firstly hydroxylated to product I by a hydroxylase, namely cytochrome P450, and then product I is rearranged to wuxistatin by isomerases. PMID:22885669

Zong, Hong; Zhuge, Bin; Fang, Huiying; Cao, Yanhui; Mu, Lin; Fu, Weilai; Song, Jian; Zhuge, Jian

2012-08-11

97

Effect of temperature on antimicrobial susceptibilities of Pseudomonas maltophilia  

Microsoft Academic Search

After a case of peritonitis caused by Pseudomonas maltophilia had occurred 20 strains of the organism were investigated and the minimum inhibitory concentrations of a variety of antibiotics determined at 30 degrees C and 37 degrees C. There was a significant difference in susceptibility between 30 degrees C (most resistant) and 37 degrees C (most susceptible) for aminoglycosides and polymyxin

P F Wheat; T G Winstanley; R C Spencer

1985-01-01

98

Controlled study of Pseudomonas cepacia and Pseudomonas maltophilia in cystic fibrosis  

Microsoft Academic Search

In a retrospective study, children with cystic fibrosis who were colonised with Pseudomonas cepacia were compared with a control group who were colonised with Pseudomonas maltophilia. Out of 216 children with cystic fibrosis seen between 1983 and 1990, P cepacia was recovered from 13 (median age at colonisation 12.2 years) and P maltophilia from 23 (median age at first colonisation

G Gladman; P J Connor; R F Williams; T J David

1992-01-01

99

Biotransformation of ursolic acid by Syncephalastrum racemosum CGMCC 3.2500 and anti-HCV activity.  

PubMed

Microbial transformation of ursolic acid (UA, 3?-hydroxy-urs-12-en-28-oic acid, 1) by filamentous fungus Syncephalastrum racemosum CGMCC 3.2500 was conducted. Five metabolites 3?, 7?, 21?-trihydroxy-urs-12-en-28-oic acid (2); 3?, 21?-dihydroxy-urs-11-en-28-oic acid-13-lactone (3); 1?, 3?, 21?-trihydroxy-urs-12-en-28-oic acid (4); 3?, 7?, 21?-trihydroxy-urs-1-en-28-oic acid-13-lactone (5); and 21-oxo-1?, 3?-dihydroxy-urs-12-en-28-oic acid (6) were afforded. Elucidation of the structures of these metabolites was primarily based on 1D and 2D NMR and HR-MS data. Metabolite 2 was a new compound. In addition, the anti-HCV activity of compounds 1-6 was evaluated. PMID:23425601

Fu, Shao-Bin; Yang, Jun-Shan; Cui, Jin-Long; Sun, Di-An

2013-02-17

100

Cloning, purification, crystallization and preliminary X-ray diffraction of the OleC protein from Stenotrophomonas maltophilia involved in head-to-head hydrocarbon biosynthesis  

PubMed Central

OleC, a biosynthetic enzyme involved in microbial hydrocarbon biosynthesis, has been crystallized. Synchrotron X-ray diffraction data have been collected to 3.4?Å resolution. The crystals belonged to space group P3121 or P3221, with unit-cell parameters a = b = 98.8, c = 141.0?Å.

Frias, Janice A.; Goblirsch, Brandon R.; Wackett, Lawrence P.; Wilmot, Carrie M.

2010-01-01

101

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

Microsoft Academic Search

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

Alvaro Hernández; Federico M. Ruiz; Antonio Romero; José L. Martínez

2011-01-01

102

Study of the anti-sapstain fungus activity of Bacillus amyloliquefaciens CGMCC 5569 associated with Ginkgo biloba and identification of its active components.  

PubMed

An endophytic bacterium, designated strain Bacillus amyloliquefaciens CGMCC 5569 was isolated from Chinese medicinal Ginkgo biloba collected from Xuzhou, China. Both the filtrate and the ethyl acetate extract of strain CGMCC 5569 showed growth inhibition activity against the sapstain fungi Lasiodiplodia rubropurpurea, L. crassispora, and L. theobromae obviously (>65%) based on the comparison of the length of zones on the petri dish. From the ethyl acetate extract of the filtrate, the antifungal compounds were obtained as a series of lipopeptides, which including series of fengycin, surfactin and bacillomycin. It showed strong growth inhibition activity in vitro against the L. rubropurpurea, L. crassispora and L. theobromae by about 70.22%, 69.53% and 78.76%, respectively. The strong anti-sapstain fungus activity indicated that the endophytic B. amyloliquefaciens CGMCC 5569 and its bioactive components might provide an alternative bio-resource for the bio-control of sapstain. PMID:22520222

Yuan, Bo; Wang, Zhe; Qin, Sheng; Zhao, Gui-Hua; Feng, You-Jian; Wei, Li-Hui; Jiang, Ji-Hong

2012-03-28

103

Effects of nitrogen sources on production and composition of sophorolipids by Wickerhamiella domercqiae var. sophorolipid CGMCC 1576.  

PubMed

The effects of nitrogen sources on growth of sophorolipid-producing yeast, Wickerhamiella domercqiae var. sophorolipid CGMCC 1576 and on production and composition of sophorolipids were studied. Organic nitrogen sources are more favorable for accumulation of biomass than inorganic ones. Presence of ammonium ion from different inorganic nitrogen sources (except NH(4)HCO(3)) greatly inhibited the production of lactonic sophorolipids. However, when organic nitrogen sources were used, lactonic sophorolipid production was strongly increased. Production of crystalline lactonic sophorolipids from organic/inorganic nitrogen sources was enhanced with the increase of pH value adjusted by sodium hydroxide or sodium citrate solution. Fourier-transform infrared (FT-IR), gas chromatography mass spectrometry (GC-MS), high-performance liquid chromatography (HPLC), and mass spectra (MS) were employed to compare the composition of sophorolipid mixture obtained from different nitrogen sources. More than 15 acidic sophorolipid molecules and only 4 lactonic sophorolipid molecules were produced by using 1.27 g/l ammonium sulfate as nitrogen source; they were separated by preparative HPLC and their structures were elucidated by MS. These results suggest extraordinary regulatory effects of nitrogen source on growth and sophorolipid synthesis of W. domercqiae var. sophorolipid. PMID:21590287

Ma, Xiao-jing; Li, Hui; Shao, Ling-jian; Shen, Jing; Song, Xin

2011-05-17

104

Enhancement of sophorolipid production of Wickerhamiella domercqiae var. sophorolipid CGMCC 1576 by low-energy ion beam implantation.  

PubMed

To meet the increasing demands of sophorolipids as biosurfactants and bioactive compounds, it is necessary to obtain higher and more specific sophorolipid-producing strains. One sophorolipid-producing strain, Wickerhamiella domercqiae var. sophorolipid CGMCC 1576 (Y(2A)), was mutated by low-energy nitrogen ion beam implantation. Eighteen mutants produced 20 % more sophorolipids than the wild strain, and one mutant, N3-18, produced the highest yield of sophorolipids, 104 g/l, in a shaking flask, which increased by 84.71 % than the wild strain, and further elevated to 135 g/l in a 5-l bioreactor. High performance liquid chromatography analysis showed that the composition of every sophorolipid mixture from different strains was similar, while the contents of most components from mutants were higher than that from the wild strain. Two mutants, N1-32 and N3-18, produced more acidic sophorolipid components; three lactonic sophorolipid molecules with good anticancer activities were greatly enhanced in several mutants, especially monoacetylated lactonic sophorolipid with a C18 monounsaturated fatty acid, which were enhanced by 153 and 211 % in strains N1-32 and N3-18. Low-energy nitrogen ion beam implantation was efficient for obtaining a variety of high and specific sophorolipid-producing mutants to be applied in food, cosmetic, environmental, and pharmaceutical sectors. PMID:22562550

Li, Hui; Ma, Xiaojing; Shao, Lingjian; Shen, Jing; Song, Xin

2012-05-06

105

Substrate specificity of Stenotrophomonas nitritireducens in the hydroxylation of unsaturated fatty acid  

Microsoft Academic Search

An isolated bacterium that converted unsaturated fatty acids to hydroxy fatty acids was identified as Stenotrophomonas nitritireducens by API analysis, cellular fatty acids compositions, sequencing the full 16S ribosomal ribonucleic acid, and evaluating its\\u000a nitrite reduction ability. S. nitritireducens has unique regio-specificity for C16 and C18 cis-9 unsaturated fatty acids. These fatty acids are converted to their 10-hydroxy fatty acids

In-Sik Yu; Soo-Jin Yeom; Hye-Jung Kim; Jung-Kul Lee; Yong-Hwi Kim; Deok-Kun Oh

2008-01-01

106

Genetic engineering to contain the Vitreoscilla hemoglobin gene enhances degradation of benzoic acid by Xanthomonas maltophilia  

SciTech Connect

Xanthomonas maltophilia was transformed with the gene encoding Vitreoscilla (bacterial) hemoglobin, vgb, and the growth of the engineered strain was compared with that of the untransformed strain using benzoic acid as the sole carbon source. In general, growth of the engineered strain was greater than that of the untransformed strain; this was true for experiments using both overnight cultures and log phase cells as inocula, but particularly for the latter. In both cases the engineered strain was also more efficiency than the untransformed strain in converting benzoic acid into biomass.

Liu, S.C.; Webster, D.A.; Wei, M.L.; Stark, B.C. [Illinois Inst. of Technology, Chicago, IL (United States)

1996-01-05

107

Isolation of the chitinolytic bacteria Xanthomonas maltophilia and Serratia marcescens as biological control agents for summer patch disease of turfgrass  

Microsoft Academic Search

A mycelial baiting method was used to isolate chitinolytic bacteria from soils known to harbor Magnaporthe poae, the causal agent of summer patch on Kentucky bluegrass. Two bacterial isolates, identified as Xanthomonas maltophilia 34S1 and Serratia marcescens 9M5, suppressed summer patch symptom development in Kentucky bluegrass cv. Baron by more than 70 and 50%, respectively, when compared to untreated control

Donald Y. Kobayashi; Mirta Guglielmoni; Bruce B. Clarke

1995-01-01

108

Biochemical properties of inducible beta-lactamases produced from Xanthomonas maltophilia.  

PubMed Central

Four different beta-lactamases have been found in several strains of Xanthomonas maltophilia isolated from blood cultures during 1984 to 1991 at the Edinburgh Royal Infirmary. One was a metallo-beta-lactamase with predominantly penicillinase activity and an isoelectric point of 6.8. Its molecular size as determined by gel filtration was 96 kDa but was only 26 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), suggesting a tetramer of four equal subunits. The enzyme hydrolyzed all classes of beta-lactams except the monobactam aztreonam. This enzyme was not inhibited by potassium clavulanate or BRL 42715 but was inhibited by p-chloromercuribenzoate, mercuric chloride, and EDTA. The beta-lactamase was unstable in 50 mM sodium phosphate buffer (pH 8.0) but stable in 50 mM Tris HCl (pH 8.0). The other beta-lactamases focused as a series of different isoelectric points, ranging from pI 5.2 to 6.6. Together, these enzymes exhibited a broad spectrum of activity, hydrolyzing most classes of beta-lactams but not imipenem or aztreonam. Their molecular size was 48 kDa by Sephadex gel filtration and 24 kDa by SDS-PAGE, indicating that they were enzymes consisting of two equal subunits. They were inhibited by p-chloromercuribenzoate, mercuric chloride, potassium clavulanate, and BRL 42715 but not EDTA. This study demonstrated that X. maltophilia produces more than just the L1 and L2 beta-lactamases. Images

Paton, R; Miles, R S; Amyes, S G

1994-01-01

109

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

110

Demonstration and partial characterization of ADP-ribosylation in Pseudomonas maltophilia.  

PubMed Central

ADP-ribosylation of proteins occurs in many eukaryotes, and it is also the mechanism of action of a growing number of important bacterial toxins. To date, however, there is only one well-characterized ADP-ribosylation system where the ADP-ribosyltransferase and the substrate protein are both bacterial in origin, namely within the nitrogen-fixing bacterium Rhodospirillum rubrum. The present paper demonstrates the endogenous ADP-ribosylation of two proteins of Mr 32,000 and 20,000 within Pseudomonas maltophilia, a Gram-negative aerobe. The proteins have been partially purified: two apparently separate species of modified protein can be separated by ion-exchange chromatography and gel filtration (V0 and Mr 158,000 - Vi). The substrate protein(s) either has, or is co-eluted with, NAD+ glycohydrolase activity. The modification is mono-ADP-ribosyl in nature. The linkage between the acceptor amino acid and the ADP-ribose moiety is alkali-labile and stable to hydroxylamine, possibly indicating an S-glycosidic bond. The activity appears to be a true ADP-ribosylation reaction and not an NAD+ glycohydrolase activity followed by non-enzymic addition of ADP-ribose to protein. The results presented here indicate that ADP-ribosylation may have a wider significance within prokaryotic systems than previously thought. Images Fig. 1.

Edmonds, C; Griffin, G E; Johnstone, A P

1989-01-01

111

Design, synthesis, and SAR of novel carbapenem antibiotics with high stability to Xanthomonas maltophilia oxyiminocephalosporinase type II.  

PubMed

Racemic cis-6-(phenylacetamido)carbapenem (21), 2-hydroxycarbonyl-cis-6-(phenylacetamido)carbapenem (22), 2-methoxycarbonyl-cis-6-(phenylacetamido)carbapenem (30), 2-methoxycarbomethyl-cis-6-(phenylacetamido)carbapenem (33), 2-hydroxyethyl-cis-6-(phenylacetamido)carbapenem (34), and 2-acetoxyethyl-cis-6-(phenylacetamido)carbapenem (35) were synthesized. Formation of the carbapenem nuclei in 21, 22, and 30 involved dehydrophosphonation of the corresponding 2-diphenylphosphono-6-(phenylacetamido)carbapenam precursors 14, 15, and 28 using trimethylsilyl triflate and 1,8-diazabicyclo[5.4.0]undec-7-ene in THF. Syntheses of carbapenems 33-35 involved a Wittig reaction of carbapenam 14 with methyl glyoxylate in the presence of lithium 2,2,6,6-tetramethylpiperidine in THF. For the antibacterial activities against Staphylococcus aureus FDA 209P, S. aureus 95, Escherichia coli ATCC 39188, Klebsiellapneumoniae NCTC 418, Pseudomonas aeruginosa 1101-75, and P. aeruginosa 18S-H, carbapenems (+/-)-21, (+/-)-22, (+/-)-30, and (+/-)-33-35 were found comparable with imipenem ((+)-3), yet they were notably more potent than (+)-3 against Xanthomonas maltophilia GN 12873. On the other hand, unlike (+)-3, carbapenems (+/-)-21, (+/-)-22, (+/-)-30, and (+/-)-33-35 were stable to X. maltophilia oxyiminocephalosporinase type II. Their beta-lactamase inhibitory properties, however, were found to be more comparable with those of penicillin G ((+)-4) than to those of imipenem ((+)-3). A combination of imipenem ((+)-3) with (+/-)-21, (+/-)-22, (+/-)-30, and (+/-)-33-35 resulted in synergistic antibacterial activity against X. maltophilia GN 12873. Results from the biological tests were correlated with the distribution of the electron density at C(2)=C(3) of carbapenems upon reaction with transpeptidases or beta-lactamases. PMID:11020277

Hakimelahi, G H; Moosavi-Movahedi, A A; Tsay, S C; Tsai, F Y; Wright, J D; Dudev, T; Hakimelahi, S; Lim, C

2000-10-01

112

Biosynthesis of gold and silver nanoparticles using a novel marine strain of Stenotrophomonas.  

PubMed

The present study aims at exploiting marine microbial diversity for biosynthesis of metal nanoparticles and also investigates role of microbial proteins in the process of bio-mineralization of gold and silver. This is the first report for concurrent production of gold and silver nanoparticles (AuNPs and AgNPs) by extracellular secretion of a novel strain of Stenotrophomonas, isolated from Indian marine origin. This novel strain has faster rate kinetics for AgNPs synthesis than any other organism reported earlier. The nanoparticles were further characterized using UV-vis spectrophotometer, TEM, DLS and EDAX confirming their size ranging from 10-50 nm and 40-60 nm in dimensions for AuNPs and AgNPs, respectively. TEM analysis indicated formation of multi-shaped nanoparticles with heterogeneous size distribution in both the cases. Finally, the SDS-PAGE analysis of extracellular media supernatant suggested a potential involvement of certain low molecular weight secretory proteins in AuNPs and AgNPs biosynthesis. PMID:23791020

Malhotra, Ankit; Dolma, Kunzes; Kaur, Navjot; Rathore, Y S; Ashish; Mayilraj, S; Choudhury, Anirban Roy

2013-05-31

113

Biodegradation of toluene and xylenes under microaerophilic and denitrifying conditions by Pseudomonas maltophilia  

SciTech Connect

Aerobic biodegradation of aromatic hydrocarbons has been well studied. Under aerobic conditions, aerobes or facultative anaerobes can utilize aromatic hydrocarbons as sole carbon and energy sources by using oxygen as the cosubstrate of oxygenase enzymes for the initial attack of the aromatic ring and as the terminal electron acceptor for aerobic respiration. However, some facultative or obligate anaerobes can degrade these hydrocarbons by using alternate electron acceptors, such as nitrate, sulfate, carbon dioxide, or iron for anaerobic respiration. Among the potential alternate electron acceptors available, nitrate is the most common one used by microorganisms under oxygen-limited conditions. The first objective of this project was to explore hydrocarbon utilization under anoxic or low oxygen conditions. A microorganism that can utilize the petroleum hydrocarbons, toluene and xylene, as sole carbon and energy sources under microaerophilic (2% oxygen) and denitrifying conditions was isolated and characterized. Since oxygen may repress microbial denitrification, it was of interest to monitor the effects of low oxygen levels on aromatic hydrocarbon biodegradation coupled to denitrification. We isolated a Gram-negative rod, Pseudomonas maltophilia from anaerobic sewage digester sludge. The patterns of biodegradations of toluene and two isomers of xylenes, m- and p-xylene, were very similar under either microaerophilic or anaerobic conditions. Nitrate reduction was also observed during time course experiments under aerobic conditions. The final objective was to test the feasibility of an immobilized cell reactor to treat waste streams. Therefore, a bench-scale bioreactor was built to treat a waste stream contaminated with both toluene and nitrate without aeration. The utilization of toluene and nitrate was monitored periodically in a continuous system under anaerobic conditions.

Su, J.J.

1994-01-01

114

Root-microbe systems: the effect and mode of interaction of Stress Protecting Agent (SPA) Stenotrophomonas rhizophila DSM14405(T.).  

PubMed

Stenotrophomonas rhizophila has great potential for applications in biotechnology and biological control due to its ability to both promote plant growth and protect roots against biotic and a-biotic stresses, yet little is known about the mode of interactions in the root-environment system. We studied mechanisms associated with osmotic stress using transcriptomic and microscopic approaches. In response to salt or root extracts, the transcriptome of S. rhizophila DSM14405(T) changed drastically. We found a notably similar response for several functional gene groups responsible for general stress protection, energy production, and cell motility. However, unique changes in the transcriptome were also observed: the negative regulation of flagella-coding genes together with the up-regulation of the genes responsible for biofilm formation and alginate biosynthesis were identified as a single mechanism of S. rhizophila DSM14405(T) against salt shock. However, production and excretion of glucosylglycerol (GG) were found as a remarkable mechanism for the stress protection of this Stenotrophomonas strain. For S. rhizophila treated with root exudates, the shift from the planktonic lifestyle to a sessile one was measured as expressed in the down-regulation of flagellar-driven motility. These findings fit well with the observed positive regulation of host colonization genes and microscopic images that show different colonization patterns of oilseed rape roots. Spermidine, described as a plant growth regulator, was also newly identified as a protector against stress. Overall, we identified mechanisms of Stenotrophomonas to protect roots against osmotic stress in the environment. In addition to both the changes in life style and energy metabolism, phytohormons, and osmoprotectants were also found to play a key role in stress protection. PMID:23717321

Alavi, Peyman; Starcher, Margaret R; Zachow, Christin; Müller, Henry; Berg, Gabriele

2013-05-14

115

Simultaneous Cr(VI) reduction and phenol degradation using Stenotrophomonas sp. isolated from tannery effluent contaminated soil.  

PubMed

This study presents simultaneous hexavalent chromium (Cr(VI)) reduction and phenol degradation using Stenotrophomonas sp., isolated from tannery effluent contaminated soil. Phenol was used as the sole carbon and energy source for Cr(VI) reduction. The optimization of different operating parameters was done using Placket-Burman design (PBD) and Box-Behnken design (BBD). The significant operating variables identified by PBD were initial Cr(VI) and phenol concentration, pH, temperature, and reaction time. These variables were optimized by a three-level BBD and the optimum initial Cr(VI) concentration, initial phenol concentration, pH, temperature, and reaction time obtained were 16.59 mg/l, 200.05 mg/l, 7.38, 31.96 °C and 4.07 days, respectively. Under the optimum conditions, 81.27 % Cr(VI) reduction and 100 % phenol degradation were observed experimentally. The results concluded that the Stenotrophomonas sp. could be used to decontaminate the effluents containing Cr(VI) and phenol effectively. PMID:23608988

Gunasundari, Dharmaraj; Muthukumar, Karuppan

2013-04-23

116

A three-component dicamba O-demethylase from Pseudomonas maltophilia, strain DI-6: gene isolation, characterization, and heterologous expression.  

PubMed

Dicamba O-demethylase is a multicomponent enzyme from Pseudomonas maltophilia, strain DI-6, that catalyzes the conversion of the widely used herbicide dicamba (2-methoxy-3,6-dichlorobenzoic acid) to DCSA (3,6-dichlorosalicylic acid). We recently described the biochemical characteristics of the three components of this enzyme (i.e. reductase(DIC), ferredoxin(DIC), and oxygenase(DIC)) and classified the oxygenase component of dicamba O-demethylase as a member of the Rieske non-heme iron family of oxygenases. In the current study, we used N-terminal and internal amino acid sequence information from the purified proteins to clone the genes that encode dicamba O-demethylase. Two reductase genes (ddmA1 and ddmA2) with predicted amino acid sequences of 408 and 409 residues were identified. The open reading frames encode 43.7- and 43.9-kDa proteins that are 99.3% identical to each other and homologous to members of the FAD-dependent pyridine nucleotide reductase family. The ferredoxin coding sequence (ddmB) specifies an 11.4-kDa protein composed of 105 residues with similarity to the adrenodoxin family of [2Fe-2S] bacterial ferredoxins. The oxygenase gene (ddmC) encodes a 37.3-kDa protein composed of 339 amino acids that is homologous to members of the Phthalate family of Rieske non-heme iron oxygenases that function as monooxygenases. Southern analysis localized the oxygenase gene to a megaplasmid in cells of P. maltophilia. Mixtures of the three highly purified recombinant dicamba O-demethylase components overexpressed in Escherichia coli converted dicamba to DCSA with an efficiency similar to that of the native enzyme, suggesting that all of the components required for optimal enzymatic activity have been identified. Computer modeling suggests that oxygenase(DIC) has strong similarities with the core alphasubunits of naphthalene 1,2-dioxygenase. Nonetheless, the present studies point to dicamba O-demethylase as an enzyme system with its own unique combination of characteristics. PMID:15855162

Herman, Patricia L; Behrens, Mark; Chakraborty, Sarbani; Chrastil, Brenda M; Barycki, Joseph; Weeks, Donald P

2005-04-26

117

Analysis of TNT (2,4,6-trinitrotoluene)-inducible cellular responses and stress shock proteome in Stenotrophomonas sp. OK-5.  

PubMed

In this study, the cellular responses of Stenotrophomonas sp. OK-5 to explosive 2,4,6-trinitrotoluene (TNT) have been extensively analyzed. The stress shock proteins, which might contribute to enhancing cellular resistance to TNT-mediated toxicity, were induced at different concentrations of TNT used as a substrate for cell culture of Stenotrophomonas sp. OK-5 capable of utilizing TNT. Proteomic analysis for 2-DE of soluble protein fractions from the culture of OK-5 exposed to TNT demonstrated approximately 300 spots on the silver-stained gel ranging from pH 3 to pH 10. Among them, 10 spots significantly induced and expressed in response to TNT were selected and analyzed. As the result of internal amino acid sequencing with ESI-Q TOF mass spectrometry, TNT-mediated stress shock proteins such as DnaK, OmpW, and OsmC were identified and characterized. Survival of strain OK-5 was periodically monitored in the presence of different concentrations of TNT along with the production of the stress shock proteins. Cells of strain OK-5 pre-exposed to TNT had in improved survival tolerance. Analysis of total cellular fatty acids in strain OK-5 suggested that several saturated or unsaturated fatty acids might increase or decrease under TNT-mediated stress condition. Scanning electron microscopy of cells treated with 0.8 mM TNT for 12 h revealed irregular rod shapes with wrinkled surfaces. PMID:15486709

Ho, Eun-Mi; Chang, Hyo-Won; Kim, Seung-Il; Kahng, Hyung-Yeel; Oh, Kye-Heon

2004-11-01

118

Biodegradation of DNA and nucleotides to nucleosides and free bases  

Microsoft Academic Search

Thirty-two different microorganisms were examined in order to check their ability to degrade an exogenous DNA. Bacteria from species: Stenotrophomonas maltophilia, Brevundimonas diminuta, Bacillus subtilis, Mycobacterium butyricum and fungus Fusarium moniliforme were capable to degrade DNA to nucleic bases or their derivatives. Degradation of DNA by S. maltophilia resulted in formation of free bases, such as hypoxanthine, thymine, uracil and

Hanna Kruszewska; Aleksandra Misicka; Urszula Chmielowiec

2004-01-01

119

Unusual respiratory bacterial flora in cystic fibrosis: microbiologic and clinical features  

Microsoft Academic Search

Pulmonary infections continue to be a significant source of morbidity and mortality among patients with cystic fibrosis. Although our understanding of the pathogenesis and clinical consequences of pulmonary infections with Pseudomonas aeruginosa has increased greatly in recent years, very little is known about potentially emerging pathogens such as Burkholderia cepacia complex, Stenotrophomonas maltophilia, Alcaligenes xylosoxidans, and methicillin-resistant Staphylococcus aureus. In

Paul M. Beringer; Maria D. Appleman

2000-01-01

120

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

2013-10-03

121

Isolation of soil Streptomyces as source antibiotics active against antibiotic-resistant bacteria  

Microsoft Academic Search

The focus of this study was the in vitro antimicrobial activities of Streptomycetes, bacteria commonly found in soil and known antibiotic-producers. Streptomycete isolates obtained from different fields in Muðla, Turkey were evaluated for their inhibitory activities on seven microorganisms including multiple antibiotic resistant Staphylococcus aureus and Stenotrophomonas maltophilia. Fifteen Streptomycete isolates which exhibited antimicrobial activity against at least two of

Ozgur Ceylan; Gulten Okmen; Aysel Ugur

2008-01-01

122

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.

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

2013-01-01

123

Biological control of Verticillium dahliae kleb. by natural occurring rhizosphere bacteria  

Microsoft Academic Search

Three bacteria were isolated from the rhizosphere of Brassica napus L. and Capsella bursa? pastoris (L.) MED. and determined as Bacillus subtilis, Pseudomonas fluorescens and Stenotrophomonas maltophilia. The efficacy of the bacterial antagonists against different phytopathogenic fungi was proven by using in vitro bioassays. Antifungal mechanisms (production of siderophores, of lytic enzymes and of antibiotics) of these isolates were also

Gabriele Berg; Christian Knaape; Günter Ballin; Dieter Seidel

1994-01-01

124

Emerging pathogens in cystic fibrosis: ten years of follow-up in a cohort of patients  

Microsoft Academic Search

In patients with cystic fibrosis (CF), there is an increasing incidence of some uncommon respiratory pathogens, such as Burkholderia cepacia complex (Bcc), Stenotrophomonas maltophilia, and Achromobacter xylosoxidans. In order to evaluate the prevalence and the clinical impact of these pathogens, we retrospectively studied a total of 109\\u000a patients followed in our center from 1996 to 2006 and reviewed the results

L. Spicuzza; C. Sciuto; G. Vitaliti; G. Di Dio; S. Leonardi; M. La Rosa

2009-01-01

125

Efficacy of copper-silver ionization in controlling biofilm- and plankton-associated waterborne pathogens.  

PubMed

The study was to determine the efficacy of copper-silver ionization against the formation of Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Acinetobacter baumannii in biofilms and planktonic phases. At concentrations below the EPA limits, ionization has potential to control the three waterborne pathogens, in addition to Legionella, in hospital water systems for nosocomial infection control. PMID:20080997

Shih, Hsiu-Yun; Lin, Yusen E

2010-01-15

126

Neonatal listeriosis followed by nosocomial infection.  

PubMed

Neonatal listeriosis is widely reported, but this is the first case reported in Serbia. A newborn developed respiratory distress syndrome 2 hours after delivery and was admitted to the neonatal intensive care unit. Initial empirical therapy was inappropriate. Consequently, on the second day, the patient developed meningitis. Listeria monocytogenes was isolated from the tracheal aspirate, blood, periumbilical swab, and cerebrospinal fluid. After bacteriology results, the therapy was changed to ampicillin and meropenem. On day 11 of hospitalization, the patient developed nosocomial infection due to multidrug-resistant Stenotrophomonas maltophilia. Since therapeutic options were limited, the patient was treated with ciprofloxacin. After 26 days of hospitalization the patient showed complete recovery and was discharged with no apparent sequelae. This case showed the importance of bacteriological examination in cases of infections caused by uncommon organisms. Pediatricians should be aware of the neonatal infection caused by Stenotrophomonas maltophilia. PMID:23867680

Dinic, M; Stankovic, S

127

Antibacterial evaluation of a collection of norfloxacin and ciprofloxacin derivatives against multiresistant bacteria  

Microsoft Academic Search

The objective of this study was to analyse an array of ciprofloxacin and norfloxacin derivatives in order to determine those with good activity against bacteria that already present fluoroquinolone resistance associated with mutations in the gyrA and\\/or parC genes. Four norfloxacin and 20 ciprofloxacin derivatives were synthesised and tested against quinolone-susceptible and -resistant Escherichia coli, Acinetobacter baumannii, Stenotrophomonas maltophilia and

J. Vila; J. Sánchez-Céspedes; J. M. Sierra; M. Piqueras; E. Nicolás; J. Freixas; E. Giralt

2006-01-01

128

Bacteremia due to glucose non-fermenting gram-negative bacilli in patients with hematological neoplasias and solid tumors  

Microsoft Academic Search

Twenty-six patients with hematological or solid tumors who developed bacteremia caused byStenotrophomonas maltophilia (n=10),Pseudomonas putida (n=6),Sphingomonas paucimobilis complex (n=4) orAlcaligenes xylosoxidans (n=6) in the period between 1993 and 1995 were studied. Seventeen patients were neutropenic during the infection, and 13 were undergoing bone marrow or peripheral blood stem cell transplantation. Twenty-three patients had catheter-related infections; only 3 of the 26

R. Martino; C. Martínez; R. Pericas; R. Salazar; C. Solfi; S. Brunet; A. Sureda; A. Domingo-Albós

1996-01-01

129

Carbapenemases: a problem in waiting?  

Microsoft Academic Search

Carbapenems are stable to most prevalent ?-lactamases, and chromosomal carbapenemases are restricted to Stenotrophomonas maltophilia, to a few Bacteroides fragilis, and to rare pathogens. Nevertheless, an acquired metallo-?-lactamase called IMP-1 is beginning to emerge in Pseudomonas aeruginosa and Enterobacteriaceae isolates in Japan, and has also been found in isolates from Singapore. Furthermore, IMP-producing Acinetobacter spp. have been identified in Italy

David M Livermore; Neil Woodford

2000-01-01

130

Antithymocyte globulin-induced acute lung injury during transplantation for aplastic anemia.  

PubMed

A 10-year-old boy with acquired, very severe aplastic anemia developed acute lung injury after the administration of equine antithymocyte globulin, during conditioning for allogenic bone marrow transplantation. Limited cases of antithymocyte globulin-induced acute lung injury have been described in adults. The respiratory worsening was sudden and required mechanical ventilation. The clinical course was complicated by sepsis with Escherichia coli, vancomycin-resistant enterococci, and Stenotrophomonas maltophilia. Implications for treatment are discussed and earlier literature is reviewed. PMID:21285902

Oberoi, Sapna; Bansal, Deepak; Sharma, Ratti Ram; Gautam, Vikas; Marwaha, Neelam; Marwaha, Ram Kumar

2011-03-01

131

Effect of organic nitrogen fertilizers on microbial populations associated with bermudagrass putting greens  

Microsoft Academic Search

Four natural organic fertilizers, alone or in combination with the synthetic organic fertilizer isobutylidene diurea (IBDU),\\u000a were compared with IBDU alone for their effect on soil\\/root microbial populations associated with bermudagrass grown on a\\u000a golf course putting green in southern Florida, USA. Populations of total fungi, total bacteria, fluorescent pseudomonads,\\u000a Stenotrophomonas maltophilia, actinomycetes and heat-tolerant bacteria were monitored every 3

M. L. Elliott; E. A. Des Jardin

1999-01-01

132

Microbiology of airway disease in a cohort of patients with Cystic Fibrosis  

Microsoft Academic Search

BACKGROUND: Recent reports document an increasing incidence of new Gram-negative pathogens such as Stenotrophomonas maltophilia and Alcaligenes xylosoxidans isolated from patients with Cystic Fibrosis, along with an increase in common Gram-negative pathogens such as Pseudomonas aeruginosa and Burkholderia cepacia complex. Furthermore, the increase in multidrug-resistance of such organisms makes the therapeutic management of these patients more problematic. Therefore, careful isolation

Antonietta Lambiase; Valeria Raia; Mariassunta Del Pezzo; Angela Sepe; Vincenzo Carnovale; Fabio Rossano

2006-01-01

133

Airborne bacteria and antibiotic resistance genes in hospital rooms  

Microsoft Academic Search

The microbial biodiversity of bioaerosols in recently occupied hospital rooms was assessed in a pulmonology unit. Environmental\\u000a samples and isolates were also screened for antibiotics resistance genes. Biofilms from sink drains were also studied to evaluate\\u000a whether sink drains constitute a potential source of bioaerosols in this environment and a reservoir for opportunistic bacteria\\u000a and antibiotic resistance genes. Stenotrophomonas maltophilia

Yan Gilbert; Marc Veillette; Caroline Duchaine

2010-01-01

134

Activities of Taurolidine In Vitro and in Experimental Enterococcal Endocarditis  

PubMed Central

In vitro, the antimicrobial agent taurolidine inhibited virtually all of the bacteria tested, including vancomycin-resistant enterococci, oxacillin-resistant staphylococci, and Stenotrophomonas maltophilia, at concentrations between 250 and 2,000 ?g/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 (<10?9) are favorable indicators for its possible development for topical use.

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

2000-01-01

135

Identification and control of bacterial contaminants from Ilex dumosa nodal segments culture in a temporal immersion bioreactor system using 16S rDNA analysis  

Microsoft Academic Search

Endogenous bacterial contaminants isolated from infected cultures of Ilex dumosa nodal segments were identified as Stenotrophomonas maltophilia and Achromobacter sp. using 16S rDNA analysis. A range of antibiotics with different mechanism of actions and the commercial biocide PPM™ were\\u000a tested for their capacity to repress the growth of Gram negative bacteria grown in liquid medium during the establishment\\u000a phase of

Claudia Luna; Mónica Collavino; Luis Mroginski; Pedro Sansberro

2008-01-01

136

[Purification and characterization of a novel alpha-galactosidase from penicillium sp. F63 CGMCC1669].  

PubMed

An a-galactosidase-producing fungus was screened out of 26 filamentous fungi isolated from soil by us. Phylogenetic analysis based on the alignment of 18S rDNA sequences, combined with the morphological identification, indicated that the strain F63 was a member of the genus Penicillium. The a-galactosidase from Penicillium sp. F63 was purified to apparent homogeneity by ammonium sulfate precipitation, ion-exchange and gel filtration chromatography. The molecular size of the purified enzyme is approximately 82kDa estimated by SDS-PAGE. The a-galactosidase has an optimum pH of 5.0 and an optimum temperature of 45 degrees C. The enzyme is stable between pH5.0 and 6.0 below 40 degrees C. The a-galactosidase activity is slightly inhibited by Ag+ , which is dissimilar to other a-galactosidases. Kinetic studies of the a-galactosidase showed that the Km and the Vmax for pNPG are 1.4mmol/L and 1.556mmol/L. min(-1) x mg- 1, respectively. The enzyme is able to degrade natural substrates such as melibiose, raffinose and stachyose but not galactose-containing polysaccharides. The alpha-galactosidase was identified by MALDI-TOF-MS and its inner peptides were sequenced by ESI-MS/MS. The results show that the a-galactosidase is a novel one. PMID:17436644

Mi, Shi-jun; Bai, Ying-guo; Meng, Kun; Wang, Ya-ru; Yao, Bin; Shi, Xiu-yun; Huang, Huo-qing; Zhang, Yu-hong; Shi, Peng-jun

2007-02-01

137

Histamine and cadaverine production by bacteria isolated from fresh and frozen albacore (Thunnus alalunga).  

PubMed

Two hundred twenty-seven bacterial strains were isolated from fresh and frozen albacore stored either at -18 or -25 degrees C and investigated for their abilities to produce biogenic amines. As a preliminary screening, all 227 strains were tested in either Niven or Niven modified medium, which allowed the selection of 25 presumptive histamine-producing strains. High-pressure liquid chromatography revealed that only 10 of the 25 strains selected were able to produce low histamine concentrations (<25 ppm) in tryptic soy broth medium supplemented with 2% histidine. None of the 25 strains tested produced putrescine or spermine, whereas 6 strains produced spermidine. Histamine production by Stenotrophomonas maltophilia strain 25MC6 was not prevented at 4 degrees C, and the levels of this amine reached concentrations of 25.8 ppm after 6 days. Three S. maltophilia strains showed strong lysine-decarboxylating activity. Their cadaverine formation capacity was determined by high-pressure liquid chromatography in tryptic soy broth supplemented with 1% lysine; this revealed that the three S. maltophilia strains tested produced more than 700 ppm of cadaverine during the first 24 h of incubation at 37 degrees C. S. maltophilia strain 15MF, initially obtained from fresh albacore tuna, produced up to 2,399 ppm and 4,820 ppm of cadaverine after 24 and 48 h of incubation at 37 degrees C, respectively. To our knowledge, this is the first report on histamine and cadaverine production by strains of the species S. maltophilia, previously known as Pseudomonas and Xanthomonas maltophilia, isolated from fresh and frozen albacore tuna. PMID:10456749

Ben-Gigirey, B; Vieites Baaptista de Sousa, J M; Villa, T G; Barros-Velazquez, J

1999-08-01

138

Complete mineralization of dodecyldimethylamine using a two-membered bacterial culture.  

PubMed

Complete degradation of dodecyldimethylamine was achieved using a two-membered bacterial culture isolated from activated sludge. One member, identified as Burkholderia cepacia, was capable of degrading the alkyl chain of the molecule. The other member, identified as Stenotrophomonas maltophilia, was able to degrade dimethylamine, the product of the former. Batch culture experiments revealed that the two-membered culture consisting of B. cepacia and S. maltophilia was based on a commensalistic relationship under carbon-limited conditions. Under nitrogen-limited conditions, the relationship of this culture was transformed from a commensalistic to a mutualistic one. A two-membered culture was therefore imperative for growth on dodecyldimethylamine under nitrogen-limited conditions, whereas a pure culture of B. cepacia was capable of growth on dodecyldimethylamine under carbon-limited conditions. PMID:11321543

Kroon, A G; van Ginkel, C G

2001-02-01

139

Bacterial strains isolated from PCB-contaminated sediments and their use for bioaugmentation strategy in microcosms.  

PubMed

This study was focused on the characterization of 15 bacterial strains isolated from long-term PCB-contaminated sediment located at the Strážsky canal in eastern part of Slovakia, in the surroundings of a former PCB producer. PCB-degrading strains were isolated and identified as Microbacterium oleivorans, Stenotrophomonas maltophilia, Brevibacterium sp., Ochrobactrum anthropi, Pseudomonas mandelii, Rhodococcus sp., Achromobacter xylosoxidans, Stenotrophomonas sp., Ochrobactrum sp., Pseudomonas aeruginosa, and Starkeya novella by the 16S rRNA gene sequence phylogenetic analysis. This study presents a newly isolated bacterial strain S. novella with PCB-degrading ability in liquid medium as well as in sediment. For A. xylosoxidans, the bphA gene was identified. The best growth ability in the presence of all sole carbon sources (biphenyl and PCBs vapor) was obtained for Ochrobactrum sp. and Rhodococcus sp. Uncultured Achromobacter sp. showed the highest potential for bioaugmentation of PCB-contaminated sediment. PMID:23553615

Dudášová, Hana; Luká?ová, Lucia; Murínová, Slavomíra; Puškárová, Andrea; Pangallo, Domenico; Dercová, Katarína

2013-04-01

140

Microbiological identification in cystic fibrosis patients with CFTR I1234V mutation.  

PubMed

Recurrent and chronic bacterial pulmonary infection is the major cause of morbidity and mortality in cystic fibrosis (CF). Over 6 months, 72 sputa or oropharyngeal samples were examined from 36 Arab Bedouin CF patients attending Hamad General Hospital, Doha, Qatar. More than 100 pathogens were isolated, mostly Haemophilus influenzae, Staphylococcus aureus and Pseudomonas aeruginosa. Unusual pathogens included Stenotrophomonas maltophilia, Acaligenes xylosoxidans and Mycobacterium abscessus. It is concluded that microbiological biodiversity in the lower airways of CF patients continues to be underestimated and that CF patients harbouring mucoid strains of P. aeruginosa are at a higher risk of acquiring more unusual organisms and probably have a worse prognosis. PMID:15357563

Wahab, A Abdul; Janahi, I A; Marafia, M M; El-Shafie, S

2004-08-01

141

Pathogen-host interactions in Dictyostelium, Legionella, Mycobacterium and other pathogens.  

PubMed

Dictyostelium discoideum is a haploid social soil amoeba that is an established host model for several human pathogens. The research areas presently pursued include the use of D. discoideum to identify genetic host factors determining the outcome of infections and the use as screening system for identifying bacterial virulence factors. Here we report about the Legionella pneumophila directed phagosome biogenesis and the cell-to-cell spread of Mycobacterium species. Moreover, we highlight recent insights from the host-pathogen cross-talk between D. discoideum and the pathogens Salmonella typhimurium, Klebsiella pneumoniae, Yersinia pseudotuberculosis, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Burkholderia cenocepacia, Vibrio cholerae and Neisseria meningitidis. PMID:21109012

Steinert, Michael

2010-11-23

142

[Prevalence of microbiota in the digestive tract of wild females of Lutzomyia longipalpis Lutz & Neiva, 1912) (Diptera: Psychodidae)].  

PubMed

We dissected the digestive tract of 245 females in pools of 35 flies forming 7 groups. These flies were Lutzomyia longipalpis originating from Lapinha Cave, Lagoa Santa, Minas Gerais. Out of the 8 species of bacteria isolated there was a predominancy of Gram negative bacterias (GNB) in the group of non-fermenters of sugar belonging to the following species: Acinetobacter lwoffii, Stenotrophomonas maltophilia, Pseudomonas putida and Flavimonas orizihabitans. The group of GNB fermenters were: Enterobacter cloacae and Klebsiella ozaenae. In the Gram positive group we isolated the genera Bacillus thuringiensis and Staphylococcus spp. PMID:10967602

Oliveira, S M; Moraes, B A; Gonçalves, C A; Giordano-Dias, C M; D'Almeida, J M; Asensi, M D; Mello, R P; Brazil, R P

143

Bacterial cis-2-unsaturated fatty acids found in the cystic fibrosis airway modulate virulence and persistence of Pseudomonas aeruginosa  

PubMed Central

There is an increasing appreciation of the polymicrobial nature of many bacterial infections such as those associated with cystic fibrosis (CF) and of the potentially important role for interspecies interactions in influencing both bacterial virulence and response to therapy. Patients with CF are often co-infected with Pseudomonas aeruginosa and other pathogens including Burkholderia cenocepacia and Stenotrophomonas maltophilia. These latter bacteria produce signal molecules of the diffusible signal factor (DSF) family, which are cis-2-unsaturated fatty acids. We have previously shown by in vitro studies that DSF from S. maltophilia leads to altered biofilm formation and increased resistance to antibiotics by P. aeruginosa; these responses of P. aeruginosa require the sensor kinase PA1396. Here we show that DSF signals are present in sputum taken from patients with CF. Presence of these DSF signals was correlated with patient colonization by S. maltophilia and/or B. cenocepacia. Analysis of 50 clinical isolates of P. aeruginosa showed that each responded to the presence of synthetic DSF by increased antibiotic resistance and these strains demonstrated little sequence variation in the PA1396 gene. In animal experiments using CF transmembrane conductance regulator knockout mice, the presence of DSF promoted P. aeruginosa persistence. Furthermore, antibiotic resistance of P. aeruginosa biofilms grown on human airway epithelial cells was enhanced in the presence of DSF. Taken together, these data provide substantial evidence that interspecies DSF-mediated bacterial interactions occur in the CF lung and may influence the efficacy of antibiotic treatment, particularly for chronic infections involving persistence of bacteria.

Twomey, Kate B; O'Connell, Oisin J; McCarthy, Yvonne; Dow, J Maxwell; O'Toole, George A; Plant, Barry J; Ryan, Robert P

2012-01-01

144

Evaluation of colistin susceptibility in multidrug-resistant clinical isolates from cystic fibrosis, France.  

PubMed

The emergence of multidrug-resistant (MDR) bacteria in cystic fibrosis (CF) patients has led to the use of colistin drug and the emergence of colistin-resistant Gram-negative bacteria. The aim of this study was to compare the disk diffusion and Etest methods for colistin susceptibility testing on MDR bacteria associated with CF from Marseille, France. Forty-nine MDR clinical isolates (27 Stenotrophomonas maltophilia, 22 Achromobacter xylosoxidans) were used in this study. Disk diffusion and Etest assays were used to assess the reliability of these two techniques. For S. maltophilia, 25 out of 27 isolates had low minimum inhibitory concentrations (MICs, 0.125-0.75 mg/L), whereas two isolates displayed high MICs (32 mg/L). Similarly, 19 out of 22 A. xylosoxidans isolates had low MICs (0.75-3.0 mg/L), whereas three isolates had high MICs (32-256 mg/L). The diameters of zone inhibition with a 50-?g colistin disk displayed a good correlation with the MICs obtained by the Etest. Susceptible and resistant strains were eventually separated using a disk diffusion assay at a cut-off of ?12 mm for a 50-?g disk. Colistin displayed excellent activity against S. maltophilia and A. xylosoxidans and the disk diffusion assay could be confidently used to determine the susceptibility to colistin for MDR Gram-negative bacteria in the context of CF. PMID:23719852

Biswas, S; Dubus, J-C; Reynaud-Gaubert, M; Stremler, N; Rolain, J-M

2013-05-30

145

Nontuberculous Mycobacteria, Fungi, and Opportunistic Pathogens in Unchlorinated Drinking Water in the Netherlands  

PubMed Central

The multiplication of opportunistic pathogens in drinking water supplies might pose a threat to public health. In this study, distributed unchlorinated drinking water from eight treatment plants in the Netherlands was sampled and analyzed for fungi, nontuberculous mycobacteria (NTM), and several opportunistic pathogens by using selective quantitative PCR methods. Fungi and NTM were detected in all drinking water samples, whereas Legionella pneumophila, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Aspergillus fumigatus were sporadically observed. Mycobacterium avium complex and Acanthamoeba spp. were not detected. Season had no influence on the occurrence of these organisms, except for NTM and S. maltophilia, which were present in higher numbers in the summer. Opportunistic pathogens were more often observed in premise plumbing water samples than in samples from the distribution system. The lowest number of these organisms was observed in the finished water at the plant. Thus, fungi, NTM, and some of the studied opportunistic pathogens can multiply in the distribution and premise plumbing systems. Assimilable organic carbon (AOC) and/or total organic carbon (TOC) had no clear effects on fungal and NTM numbers or on P. aeruginosa- and S. maltophilia-positive samples. However, L. pneumophila was detected more often in water with AOC concentrations above 10 ?g C liter?1 than in water with AOC levels below 5 ?g C liter?1. Finally, samples that contained L. pneumophila, P. aeruginosa, or S. maltophilia were more frequently positive for a second opportunistic pathogen, which shows that certain drinking water types and/or sampling locations promote the growth of multiple opportunistic pathogens.

van der Kooij, Dick

2013-01-01

146

Evaluation of the VITEK 2 System for the Identification and Susceptibility Testing of Three Species of Nonfermenting Gram-Negative Rods Frequently Isolated from Clinical Samples  

PubMed Central

VITEK 2 is a new automatic system for the identification and susceptibility testing of the most clinically important bacteria. In the present study 198 clinical isolates, including Pseudomonas aeruginosa (n = 146), Acinetobacter baumannii (n = 25), and Stenotrophomonas maltophilia (n = 27) were evaluated. Reference susceptibility testing of cefepime, cefotaxime, ceftazidime, ciprofloxacin, gentamicin, imipenem, meropenem, piperacillin, tobramycin, levofloxacin (only for P. aeruginosa), co-trimoxazole (only for S. maltophilia), and ampicillin-sulbactam and tetracycline (only for A. baumannii) was performed by microdilution (NCCLS guidelines). The VITEK 2 system correctly identified 91.6, 100, and 76% of P. aeruginosa, S. maltophilia, and A. baumannii isolates, respectively, within 3 h. The respective percentages of essential agreement (to within 1 twofold dilution) for P. aeruginosa and A. baumannii were 89.0 and 88.0% (cefepime), 91.1 and 100% (cefotaxime), 95.2 and 96.0% (ceftazidime), 98.6 and 100% (ciprofloxacin), 88.4 and 100% (gentamicin), 87.0 and 92.0% (imipenem), 85.0 and 88.0% (meropenem), 84.2 and 96.0% (piperacillin), and 97.3 and 80% (tobramycin). The essential agreement for levofloxacin against P. aeruginosa was 86.3%. The percentages of essential agreement for ampicillin-sulbactam and tetracycline against A. baumannii were 88.0 and 100%, respectively. Very major errors for P. aeruginosa (resistant by the reference method, susceptible with the VITEK 2 system [resistant to susceptible]) were noted for cefepime (0.7%), cefotaxime (0.7%), gentamicin (0.7%), imipenem (1.4%), levofloxacin (2.7%), and piperacillin (2.7%) and, for one strain of A. baumannii, for imipenem. Major errors (susceptible to resistant) were noted only for P. aeruginosa and cefepime (2.0%), ceftazidime (0.7%), and piperacillin (3.4%). Minor errors ranged from 0.0% for piperacillin to 22.6% for cefotaxime against P. aeruginosa and from 0.0% for piperacillin and ciprofloxacin to 20.0% for cefepime against A. baumannii. The VITEK 2 system provided co-trimoxazole MICs only for S. maltophilia; no very major or major errors were obtained for co-trimoxazole against this species. It is concluded that the VITEK 2 system allows the rapid identification of S. maltophilia and most P. aeruginosa and A. baumannii isolates. The VITEK 2 system can perform reliable susceptibility testing of many of the antimicrobial agents used against P. aeruginosa and A. baumannii. It would be desirable if new versions of the VITEK 2 software were able to determine MICs and the corresponding clinical categories of agents active against S. maltophilia.

Joyanes, Providencia; del Carmen Conejo, Maria; Martinez-Martinez, Luis; Perea, Evelio J.

2001-01-01

147

Class 1 integron gene cassettes in multidrug-resistant Gram-negative bacteria in southern China.  

PubMed

Non-duplicate multidrug-resistant Gram-negative bacteria (n=1447) isolated from January 2008 to December 2009 were investigated for the presence of integrons as well as characterisation of gene cassettes. Among 825 strains carrying the class 1 integrase gene intI1, 461 gene cassette-positive isolates were found. Thirty-eight distinct gene cassette arrays were identified by restriction fragment length polymorphism (RFLP) and DNA sequencing analyses. In addition, several novel gene cassette arrays detected in this study were reported for the first time in some species: one in Escherichia coli, six in Klebsiella pneumoniae, six in Enterobacter cloacae, three in Enterobacter aerogenes, one in Proteus mirabilis, one in Acinetobacter spp., one in Stenotrophomonas maltophilia and one in Pseudomonas putida. Among them, three cassettes, including HAD-like, ?MFS-1 and qnrVC-like genes, were originally detected in integrons. PMID:22817917

Wu, Kuihai; Wang, Fengping; Sun, Jingjing; Wang, Qian; Chen, Qing; Yu, Shouyi; Rui, Yongyu

2012-07-19

148

A case of unusual Gram-negative bacilli septic arthritis in an immunocompetent patient.  

PubMed

The Gram-negative bacilli Acinetobacter baumannii, Burkholderia cepacia, Ochrobactrum anthropi, Pseudomonas mendocina, Ralstonia spp., Serratia marcescens and Stenotrophomonas maltophilia are ubiquitous environmental organisms of low virulence, and do not usually cause illness in immunocompetent hosts. We report a case of multiple concurrent opportunistic Gram-negative bacilli causing septic arthritis in a healthy patient following trauma to the knee. Repeated operations, including arthroscopy, arthrotomy and debridement, were required before tissue cultures became negative. The patient also required an extended duration of intravenous and oral antibiotic treatment before he was discharged. Gram-negative bacillary septic arthritis is an uncommon but significant condition that requires repeated debridement and washouts in order to achieve bacterial eradication. This case report highlights the importance of an awareness of the external environment at the time of injury, as it impacts the type of organisms causing the infection, and consequently, the choice of empiric antibiotics required for successful treatment. PMID:24005465

Chiu, Li Qi; Wang, Wilson

2013-08-01

149

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.

Lee, Yoonjin

2013-01-01

150

Chemical composition of endemic Scorzonera sandrasica and studies on the antimicrobial activity against multiresistant bacteria.  

PubMed

The present study describes the antimicrobial activity and chemical composition of Scorzonera sandrasica Hartvig et Strid (Family Asteraceae), endemic to Turkey. The antimicrobial activity of the hexane, chloroform, ethyl acetate, and ethanol extracts of the aerial parts of S. sandrasica was evaluated against microorganisms, including multiresistant bacteria, using a paper disc diffusion method. The chemical composition of the chloroform extract of the plant was determined by gas chromatography and gas chromatography-mass spectrometry. The major compounds of the chloroform extract of the plant were caryophyllene oxide (19.7%), manoyl oxide (16.5%), and manool (11.3%), respectively. The extracts had antibacterial activity; however, no antifungal activity was observed against the two fungi. In particular, the ethanol and chloroform extracts exhibited significant activity against multiresistant strains of Stenotrophomonas maltophilia. PMID:20438328

Ugur, Aysel; Sarac, Nurdan; Ceylan, Ozgur; Duru, M Emin; Beyatli, Yavuz

2010-06-01

151

Screening for novel quorum-sensing inhibitors to interfere with the formation of Pseudomonas aeruginosa biofilm.  

PubMed

The objective of this study was to screen for novel quorum-sensing inhibitors (QSIs) from traditional Chinese medicines (TCMs) that inhibit bacterial biofilm formation. Six of 46 active components found in TCMs were identified as putative QSIs based on molecular docking studies. Of these, three compounds inhibited biofilm formation by Pseudomonas aeruginosa and Stenotrophomonas maltophilia at a concentration of 200 µM. A fourth compound (emodin) significantly inhibited biofilm formation at 20 µM and induced proteolysis of the quorum-sensing signal receptor TraR in Escherichia coli at a concentration of 3-30 mM. Emodin also increased the activity of ampicillin against P. aeruginosa. Therefore, emodin might be suitable for development into an antivirulence and antibacterial agent. PMID:21852522

Ding, Xian; Yin, Bo; Qian, Li; Zeng, Zhirui; Yang, Zeliang; Li, Huixian; Lu, Yongjun; Zhou, Shining

2011-08-18

152

Challenging and emerging pathogens in cystic fibrosis.  

PubMed

Cystic fibrosis (CF) lung disease is characterised by chronic inflammation and infection. Patients are predominantly infected by specific pathogens, of which Staphylococcus aureus and Pseudomonas aeruginosa are the most important. In recent years however there has been an increasing number of reports on potentially emerging and challenging pathogens like Stenotrophomonas maltophilia, Non-tuberculous mycobacteria, highly prevalent P. aeruginosa clones, methicillin resistant Staphylococcus aureus and Burkholderia cepacia. Also, a role for viral infections in the pathogenesis of CF lung disease has increasingly been recognised. It is not always clear whether or how these pathogens influence the progression of CF lung disease and how they should be treated. In this review, the epidemiology and clinical impact of these pathogens is discussed. Furthermore, treatment strategies of these pathogens in a CF setting are reviewed. PMID:21109184

de Vrankrijker, A M M; Wolfs, T F W; van der Ent, C K

2010-08-07

153

A novel isoquinoline alkaloid, DD-carboxypeptidase inhibitor, with antibacterial activity isolated from Streptomyces sp. 8812. Part I: Taxonomy, fermentation, isolation and biological activities.  

PubMed

A novel isoquinoline alkaloid of molecular formula C10H9NO4, labeled JS-1, was isolated from the culture broth of Streptomyces sp. 8812. It was purified by acetone protein precipitation from the culture supernatant, followed by anion exchange and C18 RP HPLC columns. JS-1 is an inhibitor of exocellular DD-carboxypeptidases/transpeptidases (DD-peptidases) 64-575 II from Saccharopolyspora erythraea 64-575 II, and R39 from Actinomadura R39. JS-1 exhibits activity against Gram-negative bacteria, such as Bordetella bronchiseptica, Stenotrophomonas maltophilia, Proteus vulgaris, P. mirabilis, Burkholderia cepacia and Acinetobacter baumanii, with MIC values 10-160 microg ml(-1), and against Gram-positive bacteria, such as Staphylococcus aureus, with MIC values 40-206 microg ml(-1). PMID:19713994

Solecka, Jolanta; Rajnisz, Aleksandra; Laudy, Agnieszka E

2009-08-28

154

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

2013-09-06

155

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.

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

2012-01-01

156

Bacterial stimulation of copper phytoaccumulation by bioaugmentation with rhizosphere bacteria.  

PubMed

Copper contaminated areas pose environmental health risk to living organisms. Remediation processes are thus required for both crop production and industrial activities. This study employed bioaugmentation with copper resistant bacteria to improve phytoremediation of vineyard soils and copper mining waste contaminated with high copper concentrations. Oatmeal plant (Avena sativa L.) was used for copper phytoextraction. Three copper resistant bacterial isolates from oatmeal rhizosphere (Pseudomonas putida A1; Stenotrophomonas maltophilia A2 and Acinetobacter calcoaceticus A6) were used for the stimulation of copper phytoextraction. Two long-term copper contaminated vineyard soils (Mollisol and Inceptisol) and copper mining waste from Southern Brazil were evaluated. Oatmeal plants substantially extracted copper from vineyard soils and copper mining waste. As much as 1549 mg of Cu kg?¹ dry mass was extracted from plants grown in Inceptisol soil. The vineyard Mollisol copper uptake (55 mg Cu kg?¹ of dry mass) in the shoots was significantly improved upon inoculation of oatmeal plants with isolate A2 (128 mg of Cu kg?¹ of shoot dry mass). Overall oatmeal plant biomass displayed higher potential of copper phytoextraction with inoculation of rhizosphere bacteria in vineyard soil to the extent that 404 and 327 g ha?¹ of copper removal were respectively observed in vineyard Mollisol bioaugmented with isolate A2 (S. maltophilia) and isolate A6 (A. calcoaceticus). Results suggest potential application of bacterial stimulation of phytoaccumulation of copper for biological removal of copper from contaminated areas. PMID:20937516

Andreazza, Robson; Okeke, Benedict C; Lambais, Márcio Rodrigues; Bortolon, Leandro; de Melo, George Wellington Bastos; Camargo, Flávio Anastácio de Oliveira

2010-11-01

157

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

158

Microbial contamination of embryos and semen during long term banking in liquid nitrogen.  

PubMed

We report on microbial contamination of embryos and semen cryopreserved in sealed plastic straws and stored for 6-35 years in liquid nitrogen. There were 32 bacterial and 1 fungal species identified from randomly drawn liquid nitrogen, frozen semen, and embryos samples stored in 8 commercial and 8 research facility liquid nitrogen (LN) tanks. The identified bacteria represented commensal or environmental microorganisms and some, such as Escherichia coli, were potential or opportunistic pathogens for humans and animals. Stenotrophomonas maltophilia was the most common contaminant identified from the samples and was further shown to significantly suppress fertilization and embryonic development in vitro. Analysis of the strains by pulsed field gel electrophoresis revealed restriction patterns with no relatedness indicating that there was no apparent cross-contamination of S. maltophilia strains between the germplasm and liquid nitrogen samples. In addition, no transmission of bovine viral diarrhea virus (BVDV) and bovine herpesvirus-1 (BHV-1) from infected semen and embryos straws to clean germplasm stored in the same LN tanks or LN was detected. PMID:12686204

Bielanski, A; Bergeron, H; Lau, P C K; Devenish, J

2003-04-01

159

Cloning, Expression and Crystallization of Heterotetrameric Sarcosine Oxidase from Pseudomonas maltophilia  

PubMed Central

Heterotetrameric sarcosine oxidase (TSOX) is a complex bifunctional enzyme that catalyzes the oxidation of the methyl group in sarcosine (N-methylglycine) and transfer of the oxidized methyl group into the 1-carbon metabolic pool. In addition to four different subunits, TSOX contains three coenzymes (FAD, FMN, NAD) and a binding site for tetrahydrofolate, the coenzyme acceptor of the oxidized methyl group from sarcosine. Based on preliminary success in crystallization of the natural enzyme, the genes encoding the subunits for TSOX from Pseudomonas maltophila (pTSOX) were cloned by functional screening of a genomic library. Recombinant enzyme exhibiting the same specific activity as natural pTSOX could not be isolated using a similar or identical purification procedure. This difficulty was overcome by affinity purification of recombinant pTSOX containing a C-terminal (His)6 tag on the subunit (?) encoded by soxG, the gene located at the 3? end of the pTSOX operon. Affinity purified pTSOX could not be crystallized, a problem traced to microheterogeneity in the recombinant enzyme where about half of the FMN is present in a modified form that is not found in the natural enzyme and may be a biosynthetic intermediate. The modified flavin was eliminated by expression of the recombinant enzyme in the presence of sarcosine, the same reagent used to induce expression of the natural enzyme. Homogenous recombinant pTSOX was isolated from cells grown in the presence of sarcosine by chromatography on affinity and hydrophobic interaction matrices. High quality crystals that diffract to 1.85 Å resolution have been obtained.

Hassan-Abdallah, Alshaimaa; Zhao, Guohua; Eschenbrenner, Michael; Chen, Zhi-wei; Mathews, F. Scott; Jorns, Marilyn Schuman

2005-01-01

160

Production of phytohormones, siderophores and population fluctuation of two root-promoting rhizobacteria in Eucalyptus globulus cuttings.  

PubMed

Vegetative propagation by stem cuttings and mini-cuttings has been used worldwide for growing Eucalyptus plants. However, clones and hybrids of this plant present a great variability in their rooting capacity, apart from a gradual decrease in the rooting potential due to the ontogenetic age of the mother plant. Several studies have demonstrated that some bacteria promote plant growth and rooting through the action of direct and indirect mechanisms that are not still completely clear. Considering this, the objective of this study was to assess the production of auxins, abscisic acid and siderophores in Bacillus subtilis and Stenotrophomona maltophilia, which in previous studies increased rooting of E. globulus cuttings. Additionally, the population of these bacteria in the rhizosphere, superficial tissues of the stem-base and callus of the mini-cuttings was identified, and quantified by real-time PCR. Only S. maltophilia produced IAA in the presence of tryptophan; none of the bacterial strains produced ABA, but both produced siderophores. A comparative analysis of the separation profiles showed that there is a diverse microbial community in the rhizosphere, and only S. maltophilia was capable of keeping its population at a density of 2.03 × 10(7) cells/mg in different tissues of the mini-cuttings. The results would indicate that the rooting stimulus in E. globulus could be related to the action of one or several mechanisms such as the production of auxins and siderophores, and it could also be associated with the ability of bacteria to stay in the rhizosphere or in plant callus tissues. PMID:22806022

Peralta, Katy Díaz; Araya, Támara; Valenzuela, Sofía; Sossa, Katherine; Martínez, Miguel; Peña-Cortés, Hugo; Sanfuentes, Eugenio

2012-01-15

161

In vitro antimicrobial activity of "last-resort" antibiotics against unusual nonfermenting Gram-negative bacilli clinical isolates.  

PubMed

In this prospective multicentric study, we assessed the in vitro antimicrobial activity of carbapenems (imipenem, meropenem, and doripenem), tigecycline, and colistin against 166 unusual nonfermenting Gram-negative bacilli (NF-GNB) clinical isolates collected from nine French hospitals during a 6-month period (from December 1, 2008, to May 31, 2009). All NF-GNB isolates were included, except those phenotypically identified as Pseudomonas aeruginosa or Acinetobacter baumannii. Minimal inhibitory concentrations (MICs) of antimicrobial agents were determined by using the E-test technique. The following microorganisms were identified: Stenotrophomonas maltophilia (n=72), Pseudomonas spp. (n=30), Achromobacter xylosoxidans (n=25), Acinetobacter spp. (n=18), Burkholderia cepacia complex (n=9), Alcaligenes faecalis (n=7), and Delftia spp. (n=5). All isolates of Acinetobacter spp., A. faecalis, and Delftia spp. were susceptible to the three carbapenems. Imipenem exhibited the lowest MICs against Pseudomonas spp., and meropenem, as compared with imipenem and doripenem, displayed an interesting antimicrobial activity against A. xylosoxidans and B. cepacia complex isolates. Conversely, no carbapenem exhibited any activity against S. maltophilia. Except for S. maltophilia isolates, tigecycline and colistin exhibited higher MICs than carbapenems, but covered most of the microorganisms tested in this study. To our knowledge, no prior study has compared antimicrobial activity of these five antibiotics, often considered as "last-resort" treatment options for resistant Gram-negative infections, against unusual NF-GNB clinical isolates. Further studies should be carried out to assess the potential clinical use of these antibiotics for the treatment of infections due to these microorganisms. PMID:22335615

Jacquier, Herve; Le Monnier, Alban; Carbonnelle, Etienne; Corvec, Stephane; Illiaquer, Marina; Bille, Emmanuelle; Zahar, Jean-Ralph; Jauréguy, Françoise; Fihman, Vincent; Tankovic, Jacques; Cattoir, Vincent

2012-02-15

162

Adhesive properties of predominant bacteria in raw cow's milk to bovine mammary gland epithelial cells.  

PubMed

Various bacteria have been found in raw cow's milk, and identifying milk microflora and its functions is critical for maintaining cow health and farm hygiene. Although studies on pathogens and spoilage bacteria in milk have been widely reported, the relationship between milk bacteria, including nonpathogenic bacteria, and the bovine udder is poorly understood. We investigated milk microflora over 1 year using a culture-dependent method and culture-independent analysis by denaturing gradient gel electrophoresis. Among 240 isolates, Lactococcus lactis (81/240) was predominant. The predominant genera were Lactococcus, Stenotrophomonas, Microbacterium, Chryseobacterium, Serratia and Pseudomonas. Among seven strains belonging to these predominant genera, two strains of L. lactis (ssp. lactis and ssp. cremoris) exhibited the highest adherence to bovine mammary gland epithelial cells (BMECs) derived from the bovine udder; 3.4 % of the inoculated bacteria adhered to BMECs. This was followed by Serratia sp. (1.6 %), Microbacterium sp. (0.8 %), Stenotrophomonas maltophilia (0.5 %), Pseudomonas sp. (0.3 %) and Chryseobacterium sp. (0.1 %). The two L. lactis isolates exhibited higher adherence to BMECs than type strains and isolates of various origins. PMID:23532507

Hagi, Tatsuro; Sasaki, Keisuke; Aso, Hisashi; Nomura, Masaru

2013-03-27

163

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

164

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.

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

2000-01-01

165

Emergence of Imipenem-Resistant Gram-Negative Bacilli in Intestinal Flora of Intensive Care Patients  

PubMed Central

Intestinal flora contains a reservoir of Gram-negative bacilli (GNB) resistant to cephalosporins, which are potentially pathogenic for intensive care unit (ICU) patients; this has led to increasing use of carbapenems. The emergence of carbapenem resistance is a major concern for ICUs. Therefore, in this study, we aimed to assess the intestinal carriage of imipenem-resistant GNB (IR-GNB) in intensive care patients. For 6 months, 523 consecutive ICU patients were screened for rectal IR-GNB colonization upon admission and weekly thereafter. The phenotypes and genotypes of all isolates were determined, and a case control study was performed to identify risk factors for colonization. The IR-GNB colonization rate increased regularly from 5.6% after 1 week to 58.6% after 6 weeks in the ICU. In all, 56 IR-GNB strains were collected from 50 patients: 36 Pseudomonas aeruginosa strains, 12 Stenotrophomonas maltophilia strains, 6 Enterobacteriaceae strains, and 2 Acinetobacter baumannii strains. In P. aeruginosa, imipenem resistance was due to chromosomally encoded resistance (32 strains) or carbapenemase production (4 strains). In the Enterobacteriaceae strains, resistance was due to AmpC cephalosporinase and/or extended-spectrum ?-lactamase production with porin loss. Genomic comparison showed that the strains were highly diverse, with 8 exceptions (4 VIM-2 carbapenemase-producing P. aeruginosa strains, 2 Klebsiella pneumoniae strains, and 2 S. maltophilia strains). The main risk factor for IR-GNB colonization was prior imipenem exposure. The odds ratio for colonization was already as high as 5.9 (95% confidence interval [95% CI], 1.5 to 25.7) after 1 to 3 days of exposure and increased to 7.8 (95% CI, 2.4 to 29.8) thereafter. In conclusion, even brief exposure to imipenem is a major risk factor for IR-GNB carriage.

Angebault, Cecile; Barbier, Francois; Hamelet, Emilie; Defrance, Gilles; Ruppe, Etienne; Bronchard, Regis; Lepeule, Raphael; Lucet, Jean-Christophe; El Mniai, Assiya; Wolff, Michel; Montravers, Philippe; Plesiat, Patrick; Andremont, Antoine

2013-01-01

166

Characterization of a soil-derived bacterial consortium degrading 4-chloroaniline.  

PubMed

A bacterial consortium comprising four different species was isolated from an Indonesian agricultural soil using a mixture of aniline and 4-chloroaniline (4CA) as principal carbon sources. The four species were identified as Chryseobacterium indologenes SB1, Comamonas testosteroni SB2, Pseudomonas corrugata SB4 and Stenotrophomonas maltophilia SB5. Growth studies on aniline and 4CA as single and mixed substrates demonstrated that the bacteria preferred to grow on and utilize aniline rather than 4CA, although both compounds were eventually depleted from the culture supernatant. However, despite 100 % disappearance of the parent substrates, the degradation of 4CA was always characterized by incomplete dechlorination and 4-chlorocatechol accumulation. This result suggests that further degradation of 4-chlorocatechol may be the rate-limiting step in the metabolism of 4CA by the bacterial consortium. HPLC-UV analysis showed that 4-chlorocatechol was further degraded via an ortho-cleavage pathway by the bacterial consortium. This hypothesis was supported by the results from enzyme assays of the crude cell extract of the consortium revealing catechol 1,2-dioxygenase activity which converted catechol and 4-chlorocatechol to cis,cis-muconic acid and 3-chloro-cis,cis-muconic acid respectively. However, the enzyme had a much higher conversion rate for catechol [156 U (g protein)(-1)] than for 4-chlorocatechol [17.2 U (g protein)(-1)], indicating preference for non-chlorinated substrates. Members of the bacterial consortium were also characterized individually. All isolates were able to assimilate aniline. P. corrugata SB4 was able to grow on 4CA solely, while S. maltophilia SB5 was able to grow on 4-chlorocatechol. These results suggest that the degradation of 4CA in the presence of aniline by the bacterial consortium was a result of interspecies interactions. PMID:14600240

Radianingtyas, Helia; Robinson, Gary K; Bull, Alan T

2003-11-01

167

Identification and susceptibility to multipurpose disinfectant solutions of bacteria isolated from contact lens storage cases of patients with corneal infiltrative events.  

PubMed

Corneal infiltrative events (CIEs) are being reported with increasing frequency in lens wearers and may be related to specific multipurpose disinfecting solution (MPDS), contact lens type or bacterial bio-burden. Here, the efficacy of MPDS's against bacteria from contact lens storage cases (CLSC) of patients with CIEs was investigated. Eighteen CLSC from patients with CIEs were cultured. All reported using the same MPDS based on PQ-1+Aldox+nonanoyl-EDTA prior to experiencing CIEs. Bacteria were identified and tested for sensitivity to MPDS-1 and three other MPSDs. 16/18 CLSC (89%) contained bacterial counts of ?10(4)-10(8)/mL. Achromobacter spp. was most frequently identified and was found in 11/18 cases (61%). This was followed by 4/18 (22%) Stenotrophomonas maltophilia, 3/18 (17%) Serratia marcescens, 3/18 (17%) Delftia spp., 2/18 (11%) Elizabethkingia spp., 2/18 (11%) Chryseobacterium indologenes and 1/18 Sphingobacterium spiritivorum. Acanthamoeba was not isolated. All of the Achromobacter strains were resistant to MPDS-1 with <1log10 kill up to 14 days exposure and the solution also showed reduced efficacy against the other isolates at the manufacturer's recommended disinfection time of 6h. Two strains of S. maltophilia and Delftia spp. grew in the solution over 14 days. Factors responsible for causing adverse events such as CIEs in contact lens wearers remain unclear. However, the presence of significant bio-burden in the contact lens storage case and lens may initiate an immunological response resulting in CIEs either directly or through the release of endotoxins (e.g. lipopolysaccharides) from the bacterial outer cell membrane. PMID:23466175

Kilvington, Simon; Shovlin, Joseph; Nikolic, Marina

2013-03-01

168

Expression of chitinase-encoding genes from Aeromonas hydrophila and Pseudomonas maltophilia in Bacillus thuringiensis subsp. israelensis  

Microsoft Academic Search

Fifty isolates of chitinase (Cts)-producing bacteria were collected from soil samples and tested for their ability to degrade chitin using colloidal chitin agar as the primary plating medium. The results indicated that three isolates could degrade chitin at high pH. Further studies also demonstrated that crude Cts preparations from Bacillus circulans (Bc) No. 4.1 could enhance the toxicity of Bacillus

Chanpen Wiwat; Monton Lertcanawanichakul; Patcharaporn Siwayapram; Somsak Pantuwatana; Amaret Bhumiratana

1996-01-01

169

Secretion, modification, and regulation of Ax21.  

PubMed

Innate immunity provides a first line of defense against pathogen attack and is activated rapidly following infection. Although it is now widely appreciated that host receptors of conserved microbial signatures play a key role in innate immunity in plants and animals, very little is known about the biological function of the microbially derived molecules recognized by such receptors. We have recently demonstrated that the rice XA21 receptor binds the AxY(S)22 peptide corresponding to the N-terminal region of Ax21, a type I-secreted protein that is highly conserved in all Xanthomonas species as well as in Xylella fastidiosa and the human pathogen, Stenotrophomonas maltophilia. We hypothesize that post-translational modification of Ax21 is carried out by the RaxP, RaxQ, and RaxST proteins and that perception and regulation of Ax21 is controlled by the RaxR/H and PhoP/Q 2-component regulatory systems. Ax21 is predicted to serve as an inducer of quorum sensing (QS), a process where bacteria communicate with one another. Because this is the first example of a conserved microbial signature that binds a host receptor and is also predicted to serve as an inducer of QS, this work has revealed fundamental new principles governing host-microbe interactions and has provided insight into the signaling dynamics of microbial communities. PMID:21236725

Han, Sang-Wook; Lee, Sang-Won; Ronald, Pamela C

2011-01-12

170

Design and quality control of a pharmaceutical formulation containing natural products with antibacterial, antifungal and antioxidant properties.  

PubMed

The aims of the present study were to determine the antibacterial and antifungal activity as well as mutagenicity of Sechium edule fluid extract and to obtain a pharmaceutical formulation with them. The extract exhibited antimicrobial activity against Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterobacter cloacae, Serratia marcescens, Morganella morganii, Acinetobacter baumannii, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Candida spp. and Aspergillus spp. isolated from clinical samples from two hospitals of Tucuman, Argentina. Non-toxicity and mutagenicity on both Salmonella typhimurium TA98 and TA 100 strains until 100 microg/plate were observed. A hydrogel with carbopol acrylic acid polymer containing S. edule fluid extract as antibacterial, antimycotic and antioxidant agent was obtained. Microbiological, physical and functional stability of pharmaceutical formulation conserved at room temperature for 1 year were determined. Addition of antioxidant preservatives to store the pharmaceutical formulation was not necessary. The semisolid system showed antimicrobial activity against all gram positive and gram negative bacteria and fungi assayed. The minimal inhibitory concentration (MIC) values ranged from 20 to 800 microg/mL. Its activity was compared with a pharmaceutical formulation containing commercial antibiotic and antifungal. A pseudoplastic behavior and positive thixotropy were observed. Our current finding shows an antimicrobial activity of hydrogel containing S. edule extract on a large range of gram negative and gram positive multi-resistant bacteria and fungi. This topical formulation may be used as antimycotic and as antibacterial in cutaneous infections. PMID:19477252

Ordoñez, Adriana A L; Ordoñez, Roxana M; Zampini, Iris C; Isla, María I

2009-05-27

171

High antibiotic susceptibility among bacterial pathogens in Swedish ICUs. Report from a nation-wide surveillance program using TA90 as a novel index of susceptibility.  

PubMed

Local infection control measures, antibiotic consumption and patient demographics from 1999-2000 together with bacteriological analyses were investigated in 29 ICUs participating in the ICU-STRAMA programme. The median antibiotic consumption per ICU was 1147 (range 605-2143) daily doses per 1000 occupied bed d (DDD1000). Antibiotics to which > 90% of isolates of an organism were susceptible were defined as treatment alternatives (TA90). The mean number of TA90 was low (1-2 per organism) for Enterococcus faecium (vancomycin:VAN), coagulase negative staphylococci (VAN), Pseudomonas aeruginosa (ceftazidime:CTZ, netilmicin: NET) and Stenotrophomonas maltophilia (CTZ, trimethoprim-sulfamethoxazole: TSU), but higher (3-7) for Acinetobacter spp. (imipenem:IMI, NET, TSU), Enterococcus faecalis (ampicillin:AMP, IMI, VAN), Serratia spp. (ciprofloxacin:CIP, IMI, NET), Enterobacter spp. (CIP, IMI, NET, TSU), E. coli (cefuroxime:CXM, cefotaxime/eftazidime:CTX/CTZ, CIP, IMI, NET, piperacillin-tazobactam:PTZ, TSU), Klebsiella spp. (CTX/CTZ CIP, IMI, NET, PTZ, TSU) and Staphylococcus aureus (clindamycin, fusidic acid, NET, oxacillin, rifampicin, VAN). Of S. aureus isolates 2% were MRSA. Facilities for alcohol hand disinfection at each bed were available in 96% of the ICUs. The numbers of TA90 available were apparently higher than in ICUs in southern Europe and the US, despite a relatively high antibiotic consumption. This may be due to a moderate ecological impact of the used agents and the infection control routines in Swedish ICUs. PMID:15000555

Hanberger, Håkan; Erlandsson, Marcus; Burman, Lars G; Cars, Otto; Gill, Hans; Lindgren, Sune; Nilsson, Lennart E; Olsson-Liljequist, Barbro; Walther, Sten

2004-01-01

172

AmpG is required for BlaXc beta-lactamase expression in Xanthomonas campestris pv. campestris str. 17.  

PubMed

The chromosomal ampR(Xc) -bla(Xc) module is essential for the ?-lactam resistance of Xanthomonas campestris pv. campestris. Bla(Xc) ?-lactamase is expressed at a high basal level in the absence of an inducer and its expression can be further induced by ?-lactam. In enterobacteria, ampG encodes an inner membrane facilitator involved in the recycling of murein degradation compounds. An isogenic ampG mutant (XcampG) of X. campestris pv. campestris str. 17 (Xc17) was constructed to investigate the link between murein recycling and bla(Xc) expression. Our data demonstrate that (1) XcampG is susceptible to ?-lactam antibiotics; (2) AmpG(Xc) is essential for expression of bla(Xc) ; (3) AmpGs of Xc17, Stenotrophomonas maltophilia KJ (SmKJ) and Escherichia coli DH5? can complement the defect of XcampG; (4) overexpression of AmpG(X) (c) significantly increased bla(Xc) expression; and (5) AmpG(Xc) from Xc17 is able to restore ?-lactamase induction of the ampN(Xc) -ampG(Xc) double mutant of SmKJ. In Xc17, ampG(Xc) can be expressed from the promoter residing in the intergenic region of ampN(Xc) -ampG(Xc) and the expression is independent of ?-lactam induction. AmpN, which is required for ?-lactamases induction in SmKJ, is not required for the ?-lactam antibiotic resistance of Xc17. PMID:23278458

Yang, Tsuey-Ching; Chen, Tzu-Fan; Tsai, Jeffrey J P; Hu, Rouh-Mei

2013-01-31

173

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 300ppm of phenanthrene and 1000ppm of naphthalene within 120h and 48h, respectively. Tween 80 showed a positive effect on phenanthrene degradation. The consortium was able to consume maximum phenanthrene at the rate of 46mg/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

2013-07-29

174

Cleavage of influenza A virus H1 hemagglutinin by swine respiratory bacterial proteases.  

PubMed Central

Cleavage of influenza A virus hemagglutinin (HA) is required for expression of fusion activity and virus entry into cells. Extracellular proteases are responsible for the proteolytic cleavage activation of avirulent avian and mammalian influenza viruses and contribute to pathogenicity and tissue tropism. The relative contributions of host and microbial proteases to cleavage activation in natural infection remain to be established. We examined 23 respiratory bacterial pathogens and 150 aerobic bacterial isolates cultured from the nasal cavities of pigs for proteolytic activity. No evidence of secreted proteases was found for the bacterial pathogens, including Haemophilus parasuis, Pasteurella multocida, Actinobacillus pleuropneumoniae, Bordetella bronchiseptica, and Streptococcus suis. Proteolytic bacteria were isolated from 7 of 11 swine nasal samples and included Staphylococcus chromogenes, Staphylococcus hyicus, Aeromonas caviae, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Enterococcus sp. Only P. aeruginosa secreted a protease, elastase, that cleaved influenza virus HA. However, compared to trypsin, the site of cleavage by elastase was shifted one amino acid in the carboxy-terminal direction and resulted in inactivation of the virus. Under the conditions of this study, we identified several bacterial isolates from the respiratory tracts of pigs that secrete proteases in vitro. However, none of these proteolytic isolates demonstrated direct cleavage activation of influenza virus HA.

Callan, R J; Hartmann, F A; West, S E; Hinshaw, V S

1997-01-01

175

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; Justé, Annelies; Crauwels, Sam; Willems, Kris; De Cooman, Luc; Lievens, Bart; Aerts, Guido

2013-07-12

176

The exposition of a calcareous Mediterranean soil to toxic concentrations of Cr, Cd and Pb produces changes in the microbiota mainly related to differential metal bioavailability.  

PubMed

The involvement of the bacterial community of an agricultural Mediterranean calcareous soil in relation to several heavy metals has been studied in microcosms under controlled laboratory conditions. Soil samples were artificially polluted with Cr(VI), Cd(II) and Pb(II) at concentrations ranging from 0.1 to 5000 mg kg(-1) and incubated along 28 d. The lowest concentrations with significant effects in soil respirometry were 10 mg kg(-1) Cr and 1000 mg kg(-1) Cd and Pb. However, only treatments showing more than 40% inhibition of respirometric activity led to significant changes in bacterial composition, as indicated by PCR-DGGE analyses. Presumable Cr- and Cd-resistant bacteria were detected in polluted microcosms, but development of the microbiota was severely impaired at the highest amendments of both metals. Results also showed that bioavailability is an important factor determining the impact of the heavy metals assayed, and even an inverted potential toxicity ranking could be achieved if their soluble fraction is considered instead of the total concentration. Moreover, multiresistant bacteria were isolated from Cr-polluted soil microcosms, some of them showing the capacity to reduce Cr(VI) concentrations between 26% and 84% of the initial value. Potentially useful strains for bioremediation were related to Arthrobacter crystallopoietes, Stenotrophomonas maltophilia and several species of Bacillus. PMID:22658943

Caliz, Joan; Montserrat, Genoveva; Martí, Esther; Sierra, Jordi; Cruañas, Robert; Garau, M Antonia; Triadó-Margarit, Xavier; Vila, Xavier

2012-06-02

177

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

178

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

179

Targeting Pan-Resistant Bacteria With Antibodies to a Broadly Conserved Surface Polysaccharide Expressed During Infection  

PubMed Central

Background New therapeutic targets for antibiotic-resistant bacterial pathogens are desperately needed. The bacterial surface polysaccharide poly-?-(1-6)-N-acetyl-glucosamine (PNAG) mediates biofilm formation by some bacterial species, and antibodies to PNAG can confer protective immunity. By analyzing sequenced genomes, we found that potentially multidrug-resistant bacterial species such as Klebsiella pneumoniae, Enterobacter cloacae, Stenotrophomonas maltophilia, and the Burkholderia cepacia complex (BCC) may be able to produce PNAG. Among patients with cystic fibrosis patients, highly antibiotic-resistant bacteria in the BCC have emerged as problematic pathogens, providing an impetus to study the potential of PNAG to be targeted for immunotherapy against pan-resistant bacterial pathogens. Methods The presence of PNAG on BCC was assessed using a combination of bacterial genetics, microscopy, and immunochemical approaches. Antibodies to PNAG were tested using opsonophagocytic assays and for protective efficacy against lethal peritonitis in mice. Results PNAG is expressed in vitro and in vivo by the BCC, and cystic fibrosis patients infected by the BCC species B. dolosa mounted a PNAG-specific opsonophagocytic antibody response. Antisera to PNAG mediated opsonophagocytic killing of BCC and were protective against lethal BCC peritonitis even during coinfection with methicillin-resistant Staphylococcus aureus. Conclusions Our findings raise potential new therapeutic options against PNAG-producing bacteria, including even pan-resistant pathogens.

Skurnik, David; Davis, Michael R.; Benedetti, Dennis; Moravec, Katie L.; Cywes-Bentley, Colette; Roux, Damien; Traficante, David C.; Walsh, Rebecca L.; Maira-Litran, Tomas; Cassidy, Sara K.; Hermos, Christina R.; Martin, Thomas R.; Thakkallapalli, Erin L.; Vargas, Sara O.; McAdam, Alexander J.; Lieberman, Tami D.; Kishony, Roy; LiPuma, John J.; Pier, Gerald B.; Goldberg, Joanna B.; Priebe, Gregory P.

2012-01-01

180

Production and characterization of monoclonal antibodies specific for the lipopolysaccharide of Escherichia coli O157.  

PubMed Central

Identification of the O157 antigen is an essential part of the detection of Escherichia coli O157:H7, which is recognized as a major etiologic agent of hemorrhagic colitis. However, polyclonal antibodies produced against E. coli O157:H7 lipopolysaccharide (LPS) may react with several other bacteria including Brucella abortus, Brucella melitensis, Yersinia enterocolitica O9, Escherichia hermannii, and Stenotrophomonas maltophilia. We produced eight monoclonal antibodies (MAbs) specific for the LPS of E. coli O157. Western blots (immunoblots) of both the phenol phase (smooth) and the aqueous phase (rough) of hot phenol-water-purified LPS indicated that three of the MAbs were specific for the O antigen and five were reactive with the LPS core. The eight MAbs could be further differentiated by their reactivities to Salmonella O30 LPS (group N), which is reported to be identical to the E. coli O157 antigen. All eight MAbs reacted strongly to all of the 64 strains of E. coli O157 tested, which included 47 isolates of O157:H7 and 17 other O157 strains. None of the eight MAbs cross-reacted with any of the 38 other E. coli serotypes tested, which consisted of 29 different O-antigen serotypes, or with 38 strains (22 genera) of non-E. coli gram-negative enteric bacteria.

Westerman, R B; He, Y; Keen, J E; Littledike, E T; Kwang, J

1997-01-01

181

Production and characterization of monoclonal antibodies specific for the lipopolysaccharide of Escherichia coli O157.  

PubMed

Identification of the O157 antigen is an essential part of the detection of Escherichia coli O157:H7, which is recognized as a major etiologic agent of hemorrhagic colitis. However, polyclonal antibodies produced against E. coli O157:H7 lipopolysaccharide (LPS) may react with several other bacteria including Brucella abortus, Brucella melitensis, Yersinia enterocolitica O9, Escherichia hermannii, and Stenotrophomonas maltophilia. We produced eight monoclonal antibodies (MAbs) specific for the LPS of E. coli O157. Western blots (immunoblots) of both the phenol phase (smooth) and the aqueous phase (rough) of hot phenol-water-purified LPS indicated that three of the MAbs were specific for the O antigen and five were reactive with the LPS core. The eight MAbs could be further differentiated by their reactivities to Salmonella O30 LPS (group N), which is reported to be identical to the E. coli O157 antigen. All eight MAbs reacted strongly to all of the 64 strains of E. coli O157 tested, which included 47 isolates of O157:H7 and 17 other O157 strains. None of the eight MAbs cross-reacted with any of the 38 other E. coli serotypes tested, which consisted of 29 different O-antigen serotypes, or with 38 strains (22 genera) of non-E. coli gram-negative enteric bacteria. PMID:9041412

Westerman, R B; He, Y; Keen, J E; Littledike, E T; Kwang, J

1997-03-01

182

Reducing the development of antibiotic resistance in critical care units.  

PubMed

Bacteria becoming resistant to an increasing number of antibiotic classes are a major problem at hospitals including critical care units worldwide. Awareness of this problem and the need to prevent the development of antibiotic resistance are very important, especially since very few new antibiotics will become available in the near future. This article gives an overview of the mechanisms of antibacterial resistance and actual resistance data worldwide of the most prevalent Gram positive (MRSA, VISA/VRSE and VRE) and Gram negative bacteria (Pseudomonas aeruginosa, Acinetobacter spp., ESBL producing Enterobacteriaceae and Stenotrophomonas maltophilia). Furthermore, strategies to reduce antibiotic resistance are reviewed. Most important is institution of infection control policies including guidelines on surveillance, isolation of colonized patients and contact precautions, hand hygiene, decolonization measures and environmental decontamination. Antimicrobial stewardship, or striking the balance between an optimal antibiotic treatment for a patient and a minimal risk of development of antibiotic resistance, is another important strategy. Finally, optimizing of antibiotic dosage regimens and thus avoiding underdosage is essential to avoid selection of the most resistant subpopulation of bacteria during antibiotic treatment. Intensive care units with knowledge of local epidemiology of resistance, an effective infection control program and antimicrobial stewardship policy tailored to their specific needs, and using optimal antibiotic dosing regimens have both locally decreased the risk of an outbreak with multi-resistant bacteria, and maybe even more important help to reduce the development of antibiotic resistance. PMID:22188438

Deege, Marjolein P D; Paterson, David L

2011-12-01

183

In vitro activity and spectrum of LY333328, a novel glycopeptide derivative.  

PubMed Central

Reference methods were used to determine the potency of LY333328, a semisynthetic glycopeptide derivative with a key N-alkylation substitution, against 833 strains (393 gram-positive strains and representative gram-negative bacilli) with various defined resistance mechanisms. The MICs at which 90% of the isolates are inhibited (MIC90S) (in micrograms per milliliter) of LY333328 and the percentages of strains at < or = 8 micrograms/ml were as follows: for oxacillin-susceptible Staphylococcus aureus, 2 and 100%, and for oxacillin-resistant Staphylococcus aureus, 4 and 100%; for oxacillin-susceptible Staphylococcus epidermis, 4 and 100%, and for oxacillin-resistant Staphylococcus aureus, 8 and 96%; for Streptococcus serogroups A, B, C, and G, 0.25 to 1 and 100%; for Streptococcus pneumoniae < or = 0.015 to 0.06 and 100%; for Enterococcus faecalis, 2 and 100%; and for vancomycin-susceptible Enterococcus faecium, 0.25 and 100%, and for vancomycin-resistant Enterococcus faecium, 4 and 100%. LY333328 was not active (MIC50, > or = 16 micrograms/ml) against more than 400 representative strains of Enterobacteriaceae, pseudomonads, Acinetobacter spp., Stenotrophomonas maltophilia, Haemophilus influenzae, Moraxella catarrhalis, pathogenic Neisseria spp., and anaerobic gram-negative bacilli. Gram-positive anaerobes were LY333328 susceptible (MICs, < or = 2 micrograms/ml). Test methods and conditions may have affected MICs of LY333328, with most (species variation) agar dilution MICs being greater than the broth microdilution MICs.

Jones, R N; Barrett, M S; Erwin, M E

1997-01-01

184

Genetic Diversity and Phylogeny of Antagonistic Bacteria against Phytophthora nicotianae Isolated from Tobacco Rhizosphere  

PubMed Central

The genetic diversity of antagonistic bacteria from the tobacco rhizosphere was examined by BOXAIR-PCR, 16S-RFLP, 16S rRNA sequence homology and phylogenetic analysis methods. These studies revealed that 4.01% of the 6652 tested had some inhibitory activity against Phytophthora nicotianae. BOXAIR-PCR analysis revealed 35 distinct amplimers aligning at a 91% similarity level, reflecting a high degree of genotypic diversity among the antagonistic bacteria. A total of 25 16S-RFLP patterns were identified representing over 33 species from 17 different genera. Our results also found a significant amount of bacterial diversity among the antagonistic bacteria compared to other published reports. For the first time; Delftia tsuruhatensis, Stenotrophomonas maltophilia, Advenella incenata, Bacillus altitudinis, Kocuria palustris, Bacillus licheniformis, Agrobacterium tumefaciens and Myroides odoratimimus are reported to display antagonistic activity towards Phytophthora nicotianae. Furthermore, the majority (75%) of the isolates assayed for antagonistic activity were Gram-positives compared to only 25% that were Gram-negative bacteria.

Jin, Fengli; Ding, Yanqin; Ding, Wei; Reddy, M.S.; Fernando, W.G. Dilantha; Du, Binghai

2011-01-01

185

Application of a continuously stirred tank bioreactor (CSTR) for bioremediation of hydrocarbon-rich industrial wastewater effluents.  

PubMed

A continuously stirred tank bioreactor (CSTR) was used to optimize feasible and reliable bioprocess system in order to treat hydrocarbon-rich industrial wastewaters. A successful bioremediation was developed by an efficient acclimatized microbial consortium. After an experimental period of 225 days, the process was shown to be highly efficient in decontaminating the wastewater. The performance of the bioaugmented reactor was demonstrated by the reduction of COD rates up to 95%. The residual total petroleum hydrocarbon (TPH) decreased from 320 mg TPH l(-1) to 8 mg TPH l(-1). Analysis using gas chromatography-mass spectrometry (GC-MS) identified 26 hydrocarbons. The use of the mixed cultures demonstrated high degradation performance for hydrocarbons range n-alkanes (C10-C35). Six microbial isolates from the CSTR were characterized and species identification was confirmed by sequencing the 16S rRNA genes. The partial 16S rRNA gene sequences demonstrated that 5 strains were closely related to Aeromonas punctata (Aeromonas caviae), Bacillus cereus, Ochrobactrum intermedium, Stenotrophomonas maltophilia and Rhodococcus sp. The 6th isolate was affiliated to genera Achromobacter. Besides, the treated wastewater could be considered as non toxic according to the phytotoxicity test since the germination index of Lepidium sativum ranged between 57 and 95%. The treatment provided satisfactory results and presents a feasible technology for the treatment of hydrocarbon-rich wastewater from petrochemical industries and petroleum refineries. PMID:21419572

Gargouri, Boutheina; Karray, Fatma; Mhiri, Najla; Aloui, Fathi; Sayadi, Sami

2011-02-24

186

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.

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

2013-01-01

187

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.

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

2012-01-01

188

Diversity and antimicrobial properties of lactic Acid bacteria isolated from rhizosphere of olive trees and desert truffles of Tunisia.  

PubMed

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

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

2013-09-14

189

Bacterial reduction of selenium in coal mine tailings pond sediment.  

PubMed

Sediment from a storage facility for coal tailings solids was assessed for its capacity to reduce selenium (Se) by native bacterial community. One Se(6+)-reducing bacterium Enterobacter hormaechei (Tar11) and four Se(4+)-reducing bacteria, Klebsiella pneumoniae (Tar1), Pseudomonas fluorescens (Tar3), Stenotrophomonas maltophilia (Tar6), and Enterobacter amnigenus (Tar8) were isolated from the sediment. Enterobacter hormaechei removed 96% of the added Se(6+) (0.92 mg L(-1)) from the effluents when Se(6+) was determined after 5 d of incubation. Analysis of the red precipitates showed that Se(6+) reduction resulted in the formation of spherical particles (<1.0 microm) 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(6+) in the sediment with or without addition of Enterobacter hormaechei cells. More than 99% of the added Se(6+) (approximately 2.5 mg L(-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(6+)- and Se(4+)-reducing bacteria and may be important sinks for soluble Se (Se(6+) and Se(4+)). Enterobacter hormaechei isolated from metal-contaminated sediment may have potential application in removing Se from industrial effluents. PMID:17412898

Siddique, Tariq; Arocena, Joselito M; Thring, Ronald W; Zhang, Yiqiang

2007-04-05

190

Polyphasic approach for the characterization of rhizobial symbionts effective in fixing N(2) with common bean (Phaseolus vulgaris L.).  

PubMed

Common bean (Phaseolus vulgaris L.) is a legume that has been reported as highly promiscuous in nodulating with a variety of rhizobial strains, often with low effectiveness in fixing nitrogen. The aim of this work was to assess the symbiotic efficiency of rhizobial strains isolated from common bean seeds, nodules of Arachis hypogaea, Mucuna pruriens, and soils from various Brazilian agroecosystems, followed by the characterization of elite strains identified in the first screening. Forty-five elite strains were analyzed for symbiotic properties (nodulation, plant-growth, and nitrogen-fixation parameters) under greenhouse conditions in pots containing non-sterile soil, and variation in symbiotic performance was observed. Elite strains were also characterized in relation to morpho-physiological properties, genetic profiles of rep-polymerase chain reaction (PCR; BOX), and restriction fragment length polymorphism (RFLP)-PCR of the 16S rRNA. Sequence analyses of the 16S rRNA were obtained for 17 strains representative of the main groups resulting from all previous analyses. One of the most effective strains, IPR-Pv 2604, was clustered with Rhizobium tropici, whereas strain IPR-Pv 583, showing lower effectiveness in fixing N(2), was clustered with Herbaspirillum lusitanum. Surprisingly, effective strains were clustered with unusual symbiotic genera/species, including Leifsonia xyli, Stenotrophomonas maltophilia, Burkholderia, and Enterobacter. Some strains recognized in this study were outstanding in their nitrogen-fixing capacity and therefore, show high biotechnological potential for use in commercial inoculants. PMID:22159885

Cardoso, Juscélio Donizete; Hungria, Mariangela; Andrade, Diva S

2011-12-09

191

Bacteria from Ips sexdentatus (Coleoptera: Curculionidae) and their biocontrol potential.  

PubMed

Ips sexdentatus (Coleoptera: Curculionidae) is one of the most destructive pests of the spruce trees in Europe. In this study, we have isolated and characterized culturable bacteria from I. sexdentatus and tested their insecticidal activity against the last instar larvae of the pest as a possible biocontrol agent. A total of eight bacterial isolates was determined and four of them were identified at species level, and the others were identified at genus level. Isolates were identified as Stenotrophomonas maltophilia (Is1), Rahnella sp. (Is2), Pseudomonas sp. (Is3), Bacillus sp. (Is4), Alcaligenes faecalis (Is5), Panteoea agglomerans (Is6), Pseudomonas fluorescens (Is7) and Serratia sp. (Is8) based on their morphological, biochemical and molecular characteristics. Insecticidal effects of bacterial isolates were performed on the last instar larvae of the pest. The highest insecticidal activity was obtained from P. fluorescens (Is7) with 73% mortality within 10 days after inoculation (p < 0.05). Mortality values of the other isolates ranged from 20 to 53%. This study suggests that Pseudomonas fluorescens (Is7) seems to be a good candidate as a possible biocontrol agent against I. sexdentatus, and provides suitable strains that can be modified to express insecticidal toxins and/or other detrimental substances to develop new control methods for I. sexdentatus. PMID:22581609

Sevim, Ali; Gökçe, Cihan; Erba?, Zeynep; Ozkan, Filiz

2012-05-14

192

Pseudomonas aeruginosa Las quorum sensing autoinducer suppresses growth and biofilm production in Legionella species.  

PubMed

Bacteria commonly communicate with each other by a cell-to-cell signalling mechanism known as quorum sensing (QS). Recent studies have shown that the Las QS autoinducer N-(3-oxododecanoyl)-l-homoserine lactone (3-oxo-C(12)-HSL) of Pseudomonas aeruginosa performs a variety of functions not only in intraspecies communication, but also in interspecies and interkingdom interactions. In this study, we report the effects of Pseudomonas 3-oxo-C(12)-HSL on the growth and suppression of virulence factors in other bacterial species that frequently co-exist with Ps. aeruginosa in nature. It was found that 3-oxo-C(12)-HSL, but not its analogues, suppressed the growth of Legionella pneumophila in a dose-dependent manner. However, 3-oxo-C(12)-HSL did not exhibit a growth-suppressive effect on Serratia marcescens, Proteus mirabilis, Escherichia coli, Alcaligenes faecalis and Stenotrophomonas maltophilia. A concentration of 50 microM 3-oxo-C(12)-HSL completely inhibited the growth of L. pneumophila. Additionally, a significant suppression of biofilm formation was demonstrated in L. pneumophila exposed to 3-oxo-C(12)-HSL. Our results suggest that the Pseudomonas QS autoinducer 3-oxo-C(12)-HSL exerts both bacteriostatic and virulence factor-suppressive activities on L. pneumophila alone. PMID:19383702

Kimura, Soichiro; Tateda, Kazuhiro; Ishii, Yoshikazu; Horikawa, Manabu; Miyairi, Shinichi; Gotoh, Naomasa; Ishiguro, Masaji; Yamaguchi, Keizo

2009-04-21

193

Genetic diversity of phenazine- and pyoluteorin-producing pseudomonads isolated from green pepper rhizosphere.  

PubMed

The genetic diversity among indigenous phenazine-1-carboxylic acid (PCA)-producing and pyoluteorin (Plt)-producing isolates of pseudomonads screened from green pepper rhizosphere was exploited in this study. A total of 48 bacterium isolates producing one or both of these antibiotics were screened from green pepper rhizosphere in diverse regions in China. Among these isolates, 45 could produce PCA, 3 could produce both PCA and Plt, and none could produce Plt only. Based on the restriction patterns of partial 16S and 16S-23S internal transcribed spacer (ITS) PCR fragments generated by enzyme HaeIII or HinfI, these isolates fell into 19 or 17 distinct groups respectively, indicating that there was a significant diversity among them. Polygenetic analysis of the partial 16S rDNA and 16S-23S ITS sequence from the representative in each group in the context of similar sequence from previously described bacterial species indicated that most isolates were closely related to the species of Pseudomonas fluorescens, P. putida, and Stenotrophomonas maltophilia. Some of these representatives of these isolates, then, are likely to be novel strains or species in these two genera. PMID:16395554

Liu, Haiming; Dong, Dexian; Peng, Huasong; Zhang, Xuehong; Xu, Yuquan

2006-01-03

194

Ciprofloxacin-Resistant Gram-Negative Bacilli in the Fecal Microflora of Children  

PubMed Central

The extent to which antibiotic-resistant bacteria are excreted by humans who have not been exposed to antibiotics is not known. Children, who rarely receive fluoroquinolones, provide opportunities to assess the frequency of fecal excretion by fluoroquinolone-naïve hosts of fluoroquinolone-resistant gram-negative bacilli. Fresh nondiarrheal stools from children were processed by screening them on agar containing ciprofloxacin to recover ciprofloxacin-resistant gram-negative bacilli. Resistant isolates were identified, and ciprofloxacin MICs were determined. Resistant Escherichia coli isolates were also analyzed for urovirulence-associated loci. Thirteen (2.9%) of 455 stools yielded ciprofloxacin-resistant E. coli (seven children), Stenotrophomonas maltophilia (four children), and Achromobacter xylosoxidans and Enterobacter aerogenes (one child each). Neither the subjects themselves nor members of their households used fluoroquinolones in the 4 weeks preceding collection. Six of the seven resistant E. coli isolates belonged to phylogenetic groups B2 and D, in which extraintestinal pathogenic E. coli bacteria are frequently found. All resistant E. coli isolates contained at least three putative E. coli virulence loci. Most ciprofloxacin-resistant bacteria were resistant to additional antibiotics. Potentially pathogenic bacteria that are resistant to therapeutically important antimicrobial agents are excreted by some humans, despite these persons' lack of exposure to the particular drugs. The sources of these resistant organisms are unknown. This underrecognized reservoir of drug-resistant potential pathogens poses public health challenges.

Qin, Xuan; Razia, Yasmin; Johnson, James R.; Stapp, Jennifer R.; Boster, Daniel R.; Tsosie, Treva; Smith, Donna L.; Braden, Christopher R.; Gay, Kathryn; Angulo, Frederick J.; Tarr, Phillip I.

2006-01-01

195

In Vitro and In Vivo Antibacterial Activities of CS-834, a New Oral Carbapenem  

PubMed Central

CS-834 is a prodrug of the carbapenem R-95867, developed by Sankyo Co., Ltd., Tokyo, Japan. To investigate the possibility that CS-834 may be the first carbapenem usable in an oral dosage form, its in vitro antibacterial activity (as R-95867) and in vivo antibacterial activity were compared with those of cefpodoxime proxetil, cefditoren pivoxil, cefdinir, ofloxacin, imipenem, and amoxicillin. R-95867 had high levels of activity against methicillin-susceptible staphylococci and streptococci, including penicillin-resistant Streptococcus pneumoniae, as well as Neisseria gonorrhoeae, Moraxella catarrhalis, the members of the family Enterobacteriaceae (with the exception of Serratia marcescens), Haemophilus influenzae, and Bordetella pertussis; for all these strains, the MICs at which 90% of tested strains are inhibited (MIC90s) were 1.0 ?g/ml or less. Against methicillin-resistant staphylococci, enterococci, Serratia marcescens, Brukholderia cepacia, Stenotrophomonas maltophilia, and Acinetobacter calcoaceticus, R-95867 showed activity comparable to or slightly less than that of imipenem, with MIC90s ranging from 2 to >128 ?g/ml. The in vivo efficacy of oral CS-834 against experimental mouse septicemia caused by gram-positive and gram-negative bacteria was better than that of comparative drugs. In murine respiratory infection models, the efficacy of CS-834 reflected not only its potent in vitro activity but also the high levels present in the lungs.

Yamaguchi, Keizo; Domon, Haruki; Miyazaki, Shuichi; Tateda, Kazuhiro; Ohno, Akira; Ishii, Kazuhiro; Matsumoto, Tetsuya; Furuya, Nobuhiko

1998-01-01

196

Histamine, cadaverine, and putrescine produced in vitro by enterobacteriaceae and pseudomonadaceae isolated from spinach.  

PubMed

A total of 364 bacterial isolates, obtained from spinach leaves, were assayed in a decarboxylase broth containing histidine, lysine, and ornithine to check their ability to produce biogenic amines, and then quantified by high-performance liquid chromatography. Among these isolates, 240 formed cadaverine, 208 formed putrescine, and 196 formed histamine, in widely varying amounts. They frequently produced more than one biogenic amine. Klebsiella pneumoniae subsp. pneumoniae and Morganella morganii were the main histamine producers, with mean values of 1,600 and 2,440 mg/liter, respectively, followed by Pantoea spp. 3 (1,710 mg/liter) and Hafnia alvei (2,500 mg/liter). Enterobacter amnigenus and Enterobacter cloacae produced particularly high amounts of putrescine, with mean values of 2,340 and 2,890 mg/liter, respectively. The strongest cadaverine formation was shown by Serratia liquefaciens (3,300 mg/liter), Serratia marcescens (3,280 mg/liter), and Stenotrophomonas maltophilia (1,000 mg/liter). PMID:20132689

Lavizzari, T; Breccia, M; Bover-Cid, S; Vidal-Carou, M C; Veciana-Nogués, M T

2010-02-01

197

Frequency of fungi in respiratory samples from Turkish cystic fibrosis patients.  

PubMed

An increased isolation of fungi from the respiratory tract of patients with cystic fibrosis (CF) has been reported. The prevalence of different fungi in CF patients from Turkey is not known. Our aim was to determine the frequency of fungi in the respiratory tract of Turkish CF patients. We investigated a total of 184 samples from 48 patients. Samples were inoculated on Medium B+ and CHROMagar Candida. Candida albicans was the predominant yeast isolated [30 patients (62.5%)], followed by C. parapsilosis [6 (12.5%)] and C. dubliniensis 5 (10.4%). Aspergillus fumigatus was the most common filamentous fungus [5 (10.4%)] and non-fumigatus Aspergillus species were isolated from four (8.3%) patients. Staphylococcus aureus was the most frequently detected bacterium in C. albicans positive samples (53.57%). A. fumigatus and Pseudomonas aeruginosa or S. aureus were detected together in 75% of A. fumigatus positive samples each. No statistically significant relationship was detected between growth of yeast and moulds and age, gender, the use of inhaled corticosteroids or tobramycin. No significant correlation was found between the isolation of C. albicans, A. fumigatus and P. aeruginosa, Stenotrophomonas maltophilia or S. aureus, and the isolation of C. albicans and Haemophilus influenzae. Other factors which may be responsible for the increased isolation of fungi in CF need to be investigated. PMID:22747891

Güngör, Ozge; Tamay, Zeynep; Güler, Nermin; Erturan, Zayre

2012-07-03

198

Isolation and characterization of phenol utilizing bacteria from industrial effluent-contaminated soil and kinetic evaluation of their biodegradation potential.  

PubMed

Microbial degradation of phenol by pure bacterial species is a well-known approach towards alleviation of environmental pollution. In this study, five phenol-degrading bacterial species designated as CUPS-1 to CUPS-5 were isolated from the oil-effluent dumped sites of Haldia Industrial area of West Bengal, India. Detailed morphological, biochemical and molecular characterization identified CUPS-3 as a novel strain- Stenotrophomonas maltophilia (GU358076), while the others could be identified as Pseudomonas (CUPS-2, 5), Delftia (CUPS-1) and Micrococcus (CUPS-4) genera, respectively. Although all of these strains utilized phenol as their sole carbon source supporting growth, three among them, CUPS-2, CUPS-3 and CUPS-5 proved potential phenol degraders and hence used for further biodegradation studies. Degradation experiments were carried out for several initial phenol concentrations of 500 mg/L, 750 mg/L, 1000 mg/L, 1250 mg/L and 1500 mg/L. The novel strain, CUPS-3 could completely degrade 500 mg/L phenol within 48 h, with 0.0937/h substrate degradation rate and 16.34 mg/L/h substrate consumption rate. The strains degraded phenol via meta-cleavage pathway. Prediction of kinetic parameters of the biodegradation was accomplished Haldane model using the experimental data of degradation rate and phenol concentration as function of time. PMID:24117085

Basak, Sreela Pal; Sarkar, Priyabrata; Pal, Priyabrata

2014-01-01

199

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; Julák, J; Kríha, V; Mosinger, J; Kopecká, S

2007-01-01

200

Microbial etiologies of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia.  

PubMed

Hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP) can be caused by a wide variety of bacteria that originate from the patient flora or the health care environment. We review the medical and microbiology literature and the results of the SENTRY Antimicrobial Surveillance Program (1997-2008) to establish the pathogens most likely to cause HABP or VABP. In all studies, a consistent 6 organisms (Staphylococcus aureus [28.0%], Pseudomonas aeruginosa [21.8%], Klebsiella species [9.8%], Escherichia coli [6.9%], Acinetobacter species [6.8%], and Enterobacter species [6.3%]) caused approximately 80% of episodes, with lower prevalences of Serratia species, Stenotrophomonas maltophilia, and community-acquired pathogens, such as pneumococci and Haemophilus influenzae. Slight changes in the pathogen order were noted among geographic regions; Latin America had an increased incidence of nonfermentative gram-negative bacilli. In addition, VABP isolates of the same species had a mean of 5%-10% less susceptibility to frequently used extended-spectrum antimicrobials, and the rate of drug resistance among HABP and VABP pathogens has been increasing by 1% per year (2004-2008). In conclusion, the empirical treatment of HABP and VABP due to prevailing bacterial causes and emerging drug resistance has become more challenging and requires use of multidrug empirical treatment regimens for routine clinical practice. These facts have profound impact on the choices of comparison therapies to be applied in contemporary new drug clinical trials for pneumonia. PMID:20597676

Jones, Ronald N

2010-08-01

201

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

2012-12-19

202

Fourier Transform Infrared Spectroscopy for Rapid Identification of Nonfermenting Gram-Negative Bacteria Isolated from Sputum Samples from Cystic Fibrosis Patients?  

PubMed Central

The accurate and rapid identification of bacteria isolated from the respiratory tract of patients with cystic fibrosis (CF) is critical in epidemiological studies, during intrahospital outbreaks, for patient treatment, and for determination of therapeutic options. While the most common organisms isolated from sputum samples are Pseudomonas aeruginosa, Staphylococcus aureus, and Haemophilus influenzae, in recent decades an increasing fraction of CF patients has been colonized by other nonfermenting (NF) gram-negative rods, such as Burkholderia cepacia complex (BCC) bacteria, Stenotrophomonas maltophilia, Ralstonia pickettii, Acinetobacter spp., and Achromobacter spp. In the present study, we developed a novel strategy for the rapid identification of NF rods based on Fourier transform infrared spectroscopy (FTIR) in combination with artificial neural networks (ANNs). A total of 15 reference strains and 169 clinical isolates of NF gram-negative bacteria recovered from sputum samples from 150 CF patients were used in this study. The clinical isolates were identified according to the guidelines for clinical microbiology practices for respiratory tract specimens from CF patients; and particularly, BCC bacteria were further identified by recA-based PCR followed by restriction fragment length polymorphism analysis with HaeIII, and their identities were confirmed by recA species-specific PCR. In addition, some strains belonging to genera different from BCC were identified by 16S rRNA gene sequencing. A standardized experimental protocol was established, and an FTIR spectral database containing more than 2,000 infrared spectra was created. The ANN identification system consisted of two hierarchical levels. The top-level network allowed the identification of P. aeruginosa, S. maltophilia, Achromobacter xylosoxidans, Acinetobacter spp., R. pickettii, and BCC bacteria with an identification success rate of 98.1%. The second-level network was developed to differentiate the four most clinically relevant species of BCC, B. cepacia, B. multivorans, B. cenocepacia, and B. stabilis (genomovars I to IV, respectively), with a correct identification rate of 93.8%. Our results demonstrate the high degree of reliability and strong potential of ANN-based FTIR spectrum analysis for the rapid identification of NF rods suitable for use in routine clinical microbiology laboratories.

Bosch, Alejandra; Minan, Alejandro; Vescina, Cecilia; Degrossi, Jose; Gatti, Blanca; Montanaro, Patricia; Messina, Matias; Franco, Mirta; Vay, Carlos; Schmitt, Juergen; Naumann, Dieter; Yantorno, Osvaldo

2008-01-01

203

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 patient’s 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

204

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

205

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

PubMed

The survival of eight undesired (spoilage/pathogenic) food related bacteria (Citrobacter freundii PSS60, Enterobacter spp. PSS11, Escherichia coli PSS2, Klebsiella oxytoca PSS82, Serratia grimesii PSS72, Pseudomonas putida PSS21, Stenotrophomonas maltophilia PSS52 and Listeria monocytogenes ATCC 19114(T)) was investigated in mineral nutrient solution (MNS) during the crop cycle of radishes (Raphanus sativus L.) cultivated in hydroponics in a greenhouse. MNSs were microbiologically analyzed weekly by plate count. The evolution of the pure cultures was also evaluated in sterile MNS in test tubes. The inoculated trials contained an initial total mesophilic count (TMC) ranging between 6.69 and 7.78Log CFU/mL, while non-sterile and sterile control trials showed levels of 4.39 and 0.97Log CFU/mL, respectively. In general, all inoculated trials showed similar levels of TMC in MNS during the experimentation, even though the levels of the inoculated bacteria decreased. The presence of the inoculums was ascertained by randomly amplified polymorphic DNA (RAPD) analysis applied on the isolates collected at 7-day intervals. At harvest, MNSs were also analyzed by denaturing gradient gel electrophoresis (DGGE). The last analysis, except P. putida PSS21 in the corresponding trial, did not detect the other bacteria, but confirmed that pseudomonads were present in un-inoculated MNSs. Despite the high counts detected (6.44 and 7.24CFU/g), only C. freundii PSS60, Enterobacter spp. PSS11 and K. oxytoca PSS82 were detected in radishes in a living form, suggesting their internalization. PMID:23290244

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

2012-11-20

206

Identification of Burkholderia cepacia isolates from patients with cystic fibrosis and use of a simple new selective medium.  

PubMed Central

We evaluated 819 isolates referred to us as "Burkholderia cepacia" from cystic fibrosis (CF) clinics and research laboratories from five countries; 28 (3.4%) were not B. cepacia. A further 12 (1.5%) organisms appeared to be other Burkholderia species, but identification could not be confirmed by conventional means. The most prevalently misidentified organisms were Stenotrophomonas maltophilia, Alcaligenes xylosoxidans, and Comamonas acidovorans. Many of these organisms grew on oxidation-fermentation polymyxin-bacitracin-lactose (OFPBL) and Pseudomonas cepacia agars, selective media currently used for B. cepacia isolation. We developed a new medium, B. cepacia selective agar (BCSA), which is more enriched for the growth of B. cepacia yet which is more selective against other organisms than currently available selective agars. A total of 190 of 191 (99.5%) isolates of B. cepacia from patients with CF grew on BCSA without vancomycin, whereas 100% grew on OFPBL agar and 179 (94.2%) grew on P. cepacia agar. Of 189 other gram-negative and gram-positive organisms tested, 10 (5.3%) grew on BCSA without vancomycin. The addition of vancomycin to BCSA lowered the false positivity rate to 3.7% without further inhibition of B. cepacia. The false positivity rates for OFPBL and P. cepacia agars were 19.6 and 13.8%, respectively. Isolates of B. cepacia from CF patients grew most quickly on BCSA, with 201 of 205 (98.0%) being readily visible within 24 h, whereas 182 (88.8%) grew on OFPBL agar and 162 (79.0%) grew on P. cepacia agar within 24 h. We propose that the use of BCSA will allow investigators to overcome many of the difficulties associated with the identification of B. cepacia and should be considered for use as a primary isolation agar for specimens from patients with CF.

Henry, D A; Campbell, M E; LiPuma, J J; Speert, D P

1997-01-01

207

Integration of molecular characterization of microorganisms in a global antimicrobial resistance surveillance program.  

PubMed

The SENTRY Antimicrobial Surveillance Program has incorporated molecular strain typing and resistance genotyping as a means of providing additional information that may be useful for understanding pathogenic microorganisms worldwide. Resistance phenotypes of interest include multidrug-resistant pathogens, extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci, and fluoroquinolone-resistant (FQR) strains of gram-negative bacilli and Streptococcus pneumoniae. Clusters of > or =2 isolates within a given resistance profile that are linked temporally and by hospital location are flagged for DNA fingerprinting. Further characterization of organisms with respect to resistance genotype is accomplished with use of polymerase chain reaction and DNA sequencing. This process has been highly successful in identifying clonal spread within clusters of multiresistant pathogens. Between 50% and 90% of MRSA clusters identified by phenotypic screening contained evidence of clonal spread. Among the Enterobacteriaceae, ESBL-producing strains of Escherichia coli and Klebsiella pneumoniae are the most common pathogens causing clusters of infection, and approximately 50% of recognized clusters demonstrate clonal spread. Clusters of Pseudomonas aeruginosa, Acinetobacter species, and Stenotrophomonas maltophilia have been noted with clonal spread among patients with urinary tract, respiratory, and bloodstream infections. Characterization of mutations in the FQR-determining region of phenotypically susceptible isolates of E. coli and S. pneumoniae has identified first-stage mutants among as many as 40% of isolates. The ability to characterize organisms phenotypically and genotypically is extremely powerful and provides unique information that is important in a global antimicrobial surveillance program. PMID:11320455

Pfaller, M A; Acar, J; Jones, R N; Verhoef, J; Turnidge, J; Sader, H S

2001-05-15

208

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.

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

2008-01-01

209

Cough-generated aerosols of Pseudomonas aeruginosa and other Gram-negative bacteria from patients with cystic fibrosis  

PubMed Central

Background: Pseudomonas aeruginosa is the most common bacterial pathogen in patients with cystic fibrosis (CF). Current infection control guidelines aim to prevent transmission via contact and respiratory droplet routes and do not consider the possibility of airborne transmission. It was hypothesised that subjects with CF produce viable respirable bacterial aerosols with coughing. Methods: A cross-sectional study was undertaken of 15 children and 13 adults with CF, 26 chronically infected with P aeruginosa. A cough aerosol sampling system enabled fractioning of respiratory particles of different sizes and culture of viable Gram-negative non-fermentative bacteria. Cough aerosols were collected during 5 min of voluntary coughing and during a sputum induction procedure when tolerated. Standardised quantitative culture and genotyping techniques were used. Results: P aeruginosa was isolated in cough aerosols of 25 subjects (89%), 22 of whom produced sputum samples. P aeruginosa from sputum and paired cough aerosols were indistinguishable by molecular typing. In four cases the same genotype was isolated from ambient room air. Approximately 70% of viable aerosols collected during voluntary coughing were of particles ?3.3 ?m aerodynamic diameter. P aeruginosa, Burkholderia cenocepacia, Stenotrophomonas maltophilia and Achromobacter xylosoxidans were cultivated from respiratory particles in this size range. Positive room air samples were associated with high total counts in cough aerosols (p?=?0.003). The magnitude of cough aerosols was associated with higher forced expiratory volume in 1 s (r?=?0.45, p?=?0.02) and higher quantitative sputum culture results (r?=?0.58, p?=?0.008). Conclusion: During coughing, patients with CF produce viable aerosols of P aeruginosa and other Gram-negative bacteria of respirable size range, suggesting the potential for airborne transmission.

Wainwright, C E; France, M W; O'Rourke, P; Anuj, S; Kidd, T J; Nissen, M D; Sloots, T P; Coulter, C; Ristovski, Z; Hargreaves, M; Rose, B R; Harbour, C; Bell, S C; Fennelly, K P

2009-01-01

210

Intragenomic and intraspecific heterogeneity of the 16S rRNA gene in seven bacterial species from the respiratory tract of cystic fibrosis patients assessed by PCR-Temporal Temperature Gel Electrophoresis.  

PubMed

16S rRNA gene-based cultivation-independent methods are increasingly used to study the diversity of microbiota during health and disease. One bias of these methods is the variability of 16S rRNA gene that may exist among strains of a same species (intraspecific heterogeneity) or between rrs copies in a genome (intragenomic heterogeneity). We evaluated the level of intraspecific and intragenomic 16S rDNA variability in seven species frequently encountered in respiratory tract samples in cystic fibrosis (CF). A total of 179 strains were subjected to V3 region 16S rDNA PCR-TTGE. Using this easy-to-perform and rapid method, different levels of V3 region rrs heterogeneity were demonstrated. No intraspecific and intragenomic rrs heterogeneity was demonstrated for Moraxella catarrhalis (n=16), Pseudomonas aeruginosa (n=31) and Streptococcus pneumoniae (n=14) showing a single PCR-TTGE band characteristic of the species. Low level of intraspecific heterogeneity was observed for Staphylococcus aureus (n=30), Stenotrophomonas maltophilia (n=29) and Achromobacter xylosoxidans (n=28), and 17%, 38% and 96% of these strains showed intragenomic heterogeneity (two to four different rrs copies), respectively. Haemophilus influenzae (n=31) displayed the higher level of intraspecific variability with 23 different PCR-TTGE patterns and 61% of the strains showed intragenomic rrs heterogeneity (two to four different rrs copies). Although only one hypervariable region of the 16S rRNA gene was explored, intraspecific and intragenomic rrs heterogeneity was frequently observed in this study and should be taken into consideration for a better interpretation of 16S rRNA gene-based diversity profiles in denaturing gels and to avoid any overestimation of the respiratory microbiota diversity in CF. PMID:21621347

Michon, A-L; Jumas-Bilak, E; Imbert, A; Aleyrangues, L; Counil, F; Chiron, R; Marchandin, H

2011-05-31

211

[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 Fundación Favaloro, the Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia and the Hospital de Niños Ricardo Gutiérrez. 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; Fernández, A; Zudiker, R; Echeverría, A; Nagel, C; del Castillo, M; López, E; Gutfraind, Z; Tokumoto, M; Guelfand, L

212

Composting and vermicomposting experiences in the treatment and bioconversion of asphaltens from the Prestige oil spill.  

PubMed

This work illustrates the effectiveness of composting and vermicomposting in degrading fuel-in-water emulsions from oil spills (chapapote), and the isolation of potentially useful microorganisms for its biodegradation. Firstly, an alternative to the biodegradation of asphaltens from the Prestige oil spill (still present in some chapapote rafts in the Cantabrian coast) by means of the application of composting techniques to a microbial partnership acclimated to fuel-oil is offered. Our aim is that, after a relatively short period of time, the microorganisms can obtain its source of carbon and energy from asphaltens. The addition of metabolic co-substrates, like cow bed and potato peelings, allows the fragmentation of complex compounds into smaller structures, susceptible to further degradation. Afterwards, a maturation of the compost by means of a treatment with earthworms (Eisenia foetida) is necessary. Thus, through the vermicomposting it will be possible to obtain a valued product, useful in the processes of ground amendment, with little presence of asphaltens and occluded polycyclic aromatic hydrocarbons, rich in humus, and with an important bacterial flora of Bacillus genera, so that it can be typical of co-activators and accelerating products in composting processes. Along with this article, we show some parameters that control the evolution of the compost products (evolved gases, acidity, temperature and humidity); the chemical and microbiological analytical results; and the germination assays of vermicomposting. Results reveal that by using microorganisms living in either earthworm intestines (Stenotrophomonas maltophilia) or vermiculture substrates (Scedosporium apiospermium), it is possible to degrade and to eliminate the polycyclic asphaltens into CO(2) and H(2)O, helped by evaporation, dissolution and/or photo-oxidation processes. The obtained end product has contents of interesting vegetal nutrients and, mainly, it displays very high germination indices. PMID:17512195

Martín-Gil, Jesús; Navas-Gracia, Luís Manuel; Gómez-Sobrino, Ernesto; Correa-Guimaraes, Adriana; Hernández-Navarro, Salvador; Sánchez-Báscones, Mercedes; del Carmen Ramos-Sánchez, María

2007-05-23

213

['In vitro' activity of different antimicrobial agents on Gram-negative nonfermentative bacilli, excluding Pseudomonas aeruginosa and Acinetobacter spp].  

PubMed

Gram-negative nonfermentative bacilli (NFB) are widely spread in the environment. Besides of difficulties for identification, they often have a marked multiresistance to antimicrobial agents, including those active against Pseudomonas aeruginosa. The objective of this study was to evaluate the 'in vitro' activity of different antimicrobial agents on 177 gram-negative nonfermentative bacilli isolates (excluding Pseudomonas aeruginosa and Acinetobacter spp.) isolated from clinical specimens. Minimum inhibitory concentrations (MIC) were determined according to the Mueller Hinton agar dilution method against the following antibacterial agents: ampicillin, piperacillin, piperacillin-tazobactam, sulbactam, cefoperazone, cefoperazone-sulbactam, ceftazidime, cefepime, aztreonam, imipenem, meropenem, colistin, gentamicin, amikacin, trimethoprim-sulfamethoxazole, chloramphenicol, erythromycin, rifampin, norfloxacin, ciprofloxacin and minocycline. Seven isolates: Sphingobacterium multivorum (2), Sphingobacteriumspiritivorum (1), Empedobacterbrevis (1), Weeksella virosa (1), Bergeyella zoohelcum (1) and Oligella urethralis (1), were tested for amoxicillin-clavulanic acid and ampicillin-sulbactam susceptibility, and susceptibility to cefoperazone or sulbactam was not determined. Multiresistance was generally found in Stenotrophomonas maltophilia, Burkholderia cepacia, Chryseobacterium spp., Myroides spp., Achromobacter xylosoxidans, and Ochrobactrum anthropi isolates. On the other hand, Pseudomonas stutzeri, Shewanella putrefaciens-algae, Sphingomonas paucimobilis, and Pseudomonas oryzihabitans, Bergeyella zoohelcum, Weeksella virosa and Oligella urethralis were widely susceptible to the antibacterial agents tested. As a result of the wide variation in antimicrobial susceptibility shown by different species, a test on susceptibility to different antibacterial agents is essential in order to select an adequate therapy. The marked multiresistance evidenced by some species, prompts the need to develop new antimicrobial agents active against this group of bacteria and to search for synergistic combinations. PMID:15991478

Vay, C A; Almuzara, M N; Rodríguez, C H; Pugliese, M L; Lorenzo Barba, F; Mattera, J C; Famiglietti, A M R

214

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

2013-08-30

215

Yersinia enterocolitica and Photorhabdus asymbiotica ?-lactamases BlaA are exported by the twin-arginine translocation pathway.  

PubMed

In general, ?-lactamases of medically important Gram-negative bacteria are Sec-dependently translocated into the periplasm. In contrast, ?-lactamases of Mycobacteria spp. (BlaC, BlaS) and the Gram-negative environmental bacteria Stenotrophomonas maltophilia (L2) and Xanthomonas campestris (Bla(XCC-1)) have been reported to be secreted by the twin-arginine translocation (Tat) system. Yersinia enterocolitica carries 2 distinct ?-lactamase genes (blaA and blaB) encoding BlaA(Ye) and the AmpC-like ?-lactamase BlaB, respectively. By using the software PRED-TAT for prediction and discrimination of Sec from Tat signal peptides, we identified a functional Tat signal sequence for Yersinia BlaA(Ye). The Tat-dependent translocation of BlaA(Ye) could be clearly demonstrated by using a Y. enterocolitica tatC-mutant and cell fractionation. Moreover, we could demonstrate a unique unusual temperature-dependent activity profile of BlaA(Ye) ranging from 15 to 60 °C and a high 'melting temperature' (T(M)=44.3°) in comparison to the related Sec-dependent ?-lactamase TEM-1 (20-50°C, T(M)=34.9 °C). Strikingly, the blaA gene of Y. enterocolitica is present in diverse environmental Yersinia spp. and a blaA homolog gene could be identified in the closely related Photorhabdus asymbiotica (BlaA(Pa); 69% identity to BlaA(Ye)). For BlaA(Pa) of P. asymbiotica, we could also demonstrate Tat-dependent secretion. These results suggest that Yersinia BlaA-related ?-lactamases may be the prototype of a large Tat-dependent ?-lactamase family, which originated from environmental bacteria. PMID:23276548

Schriefer, Eva-Maria; Hoffmann-Thoms, Stephanie; Schmid, Franz X; Schmid, Annika; Heesemann, Jürgen

2012-12-29

216

Pathogenic analysis of sputum from ventilator-associated pneumonia in a pediatric intensive care unit.  

PubMed

Ventilator-associated pneumonia (VAP) is a common and sometimes fatal complication in pediatric intensive care units (PICU). The aim of our study was to characterize the distribution and drug susceptibility of the pathogens isolated from the sputum of patients with VAP in the PICU of our hospital and to provide support to the administration of antibiotics early and reasonably in the clinic. Our study was conducted between January 2007 and December 2011 at the PICU of the Children's Hospital of Zhejiang University School of Medicine. The endotracheal aspirates were collected and transported to a microbiology laboratory within 15 min. The pathogens were routinely analyzed and identified with Vitek 60 and Kirby-Bauer disk diffusion methods. Among the 121 VAP patients, 127 pathogenic strains were isolated from sputum specimens. Gram-negative and gram-positive bacteria and fungi accounted for 64.57% (82/127), 29.92% (38/127) and 5.51% (7/127), respectively. Acinetobacter baumannii (25.61%), Escherichia coli (20.27%), Stenotrophomonas maltophilia (20.27%), Klebsiella pneumoniae (16.22%) and Pseudomonas aeruginosa (9.46%) were frequently identified isolates among gram-negative bacteria. Staphylococci were susceptible to vancomycin and linezolid. All fungi were sensitive to the antimicrobial agents. The gram-negative bacteria were more prevalent than gram-positive bacteria and fungi in VAP and demonstrated a higher drug resistance. It is important to administer antimicrobial agents early and reasonably for children with VAP. Knowledge of antibiotic resistance and the characteristics of drug resistance is important for VAP prophylaxis and treatment. PMID:23251300

Ning, Bo-Tao; Zhang, Chen-Mei; Liu, Tao; Ye, Sheng; Yang, Zi-Hao; Chen, Zhen-Jie

2012-10-22

217

Pathogenic analysis of sputum from ventilator-associated pneumonia in a pediatric intensive care unit  

PubMed Central

Ventilator-associated pneumonia (VAP) is a common and sometimes fatal complication in pediatric intensive care units (PICU). The aim of our study was to characterize the distribution and drug susceptibility of the pathogens isolated from the sputum of patients with VAP in the PICU of our hospital and to provide support to the administration of antibiotics early and reasonably in the clinic. Our study was conducted between January 2007 and December 2011 at the PICU of the Children’s Hospital of Zhejiang University School of Medicine. The endotracheal aspirates were collected and transported to a microbiology laboratory within 15 min. The pathogens were routinely analyzed and identified with Vitek 60 and Kirby-Bauer disk diffusion methods. Among the 121 VAP patients, 127 pathogenic strains were isolated from sputum specimens. Gram-negative and gram-positive bacteria and fungi accounted for 64.57% (82/127), 29.92% (38/127) and 5.51% (7/127), respectively. Acinetobacter baumannii (25.61%), Escherichia coli (20.27%), Stenotrophomonas maltophilia (20.27%), Klebsiella pneumoniae (16.22%) and Pseudomonas aeruginosa (9.46%) were frequently identified isolates among gram-negative bacteria. Staphylococci were susceptible to vancomycin and linezolid. All fungi were sensitive to the antimicrobial agents. The gram-negative bacteria were more prevalent than gram-positive bacteria and fungi in VAP and demonstrated a higher drug resistance. It is important to administer antimicrobial agents early and reasonably for children with VAP. Knowledge of antibiotic resistance and the characteristics of drug resistance is important for VAP prophylaxis and treatment.

NING, BO-TAO; ZHANG, CHEN-MEI; LIU, TAO; YE, SHENG; YANG, ZI-HAO; CHEN, ZHEN-JIE

2013-01-01

218

Prevalence of antimicrobial resistance among gram-negative isolates in an adult intensive care unit at a tertiary care center in Saudi Arabia  

PubMed Central

BACKGROUND AND OBJECTIVES: Patients in the ICU have encountered an increasing emergence and spread of antibiotic-resistant pathogens. We examined patterns of antimicrobial susceptibility in gram-negative isolates to commonly used drugs in an adult ICU at a tertiary care hospital in Riyadh, Saudi Arabia. METHODS: A retrospective study was carried out of gram-negative isolates from the adult ICU of King Fahad National Guard Hospital (KFNGH) between 2004 and 2009. Organisms were identified and tested by an automated identification and susceptibility system, and the antibiotic susceptibility testing was confirmed by the disk diffusion method. RESULTS: The most frequently isolated organism was Acinetobacter baumannii, followed by Pseudomonas aeruginosa, Escherichia coli, Klebsiella pnemoniae, Stenotrophomonas maltophilia, and Enterobacter. Antibiotic susceptibility patterns significantly declined in many organisms, especially A baumannii, E coli, S marcescens, and Enterobacter. A baumannii susceptibility was significantly decreased to imipenem (55% to 10%), meropenem (33% to 10%), ciprofloxacin (22% to 10%), and amikacin (12% to 6%). E coli susceptibility was markedly decreased (from 75% to 50% or less) to cefuroxime, ceftazidime, cefotaxime, and cefepime. S marcescens susceptibility was markedly decreased to cefotaxime (100% to 32%), ceftazidime (100% to 35%), and cefepime (100% to 66%). Enterobacter susceptibility was markedly decreased to ceftazidime (34% to 5%), cefotaxime (34% to 6%), and pipracillin-tazobactam (51% to 35%). Respiratory samples were the most frequently indicative of multidrug-resistant pathogens (63%), followed by urinary samples (57%). CONCLUSION: Antimicrobial resistance is an emerging problem in the KFNGH ICU, justifying new more stringent antibiotic prescription guidelines. Continuous monitoring of antimicrobial susceptibility and strict adherence to infection prevention guidelines are essential to eliminate major outbreaks in the future.

Al Johani, Sameera M.; Akhter, Javed; Balkhy, Hanan; El-Saed, Ayman; Younan, Mousaad; Memish, Ziad

2010-01-01

219

Microbial consortia that degrade 2,4-DNT by interspecies metabolism: isolation and characterisation.  

PubMed

Two consortia, isolated by selective enrichment from a soil sample of a nitroaromatic-contaminated site, degraded 2,4-DNT as their sole nitrogen source without accumulating one or more detectable intermediates. Though originating from the same sample, the optimised consortia had no common members, indicating that selective enrichment resulted in different end points. Consortium 1 and consortium 2 contained four and six bacterial species respectively, but both had two members that were able to collectively degrade 2,4-DNT. Variovorax paradoxus VM685 (consortium 1) and Pseudomonas sp. VM908 (consortium 2) initiate the catabolism of 2,4-DNT by an oxidation step, thereby releasing nitrite and forming 4-methyl-5-nitrocatechol (4M5NC). Both strains contained a gene similar to the dntAa gene encoding 2,4-DNT dioxygenase. They subsequently metabolised 4M5NC to 2-hydroxy-5-methylquinone (2H5MQ) and nitrite, indicative of DntB or 4M5NC monooxygenase activity. A second consortium member, Pseudomonas marginalis VM683 (consortium 1) and P. aeruginosa VM903, Sphingomonas sp. VM904, Stenotrophomonas maltophilia VM905 or P. viridiflava VM907 (consortium 2), was found to be indispensable for efficient growth of the consortia on 2,4-DNT and for efficient metabolisation of the intermediates 4M5NC and 2H5MQ. Knowledge about the interactions in this step of the degradation pathway is rather limited. In addition, both consortia can use 2,4-DNT as sole nitrogen and carbon source. A gene similar to the dntD gene of Burkholderia sp. strain DNT that catalyses ring fission was demonstrated by DNA hybridisation in the second member strains. To our knowledge, this is the first time that consortia are shown to be necessary for 2,4-DNT degradation. PMID:12801097

Snellinx, Zita; Taghavi, Safieh; Vangronsveld, Jaco; van der Lelie, Daniël

2003-01-01

220

Fulminant pertussis: a multi-center study with new insights into the clinico-pathological mechanisms.  

PubMed

Pertussis carries a high risk of mortality in very young infants. The mechanism of refractory cardio-respiratory failure is complex and not clearly delineated. We aimed to examine the clinico-pathological features and suggest how they may be related to outcome, by multi-center review of clinical records and post-mortem findings of 10 patients with fulminant pertussis (FP). All cases were less than 8 weeks of age, and required ventilation for worsening respiratory symptoms and inotropic support for severe hemodynamic compromise. All died or underwent extra corporeal membrane oxygenation (ECMO) within 1 week. All had increased leukocyte counts (from 54 to 132 x 10(9)/L) with prominent neutrophilia in 9/10. The post-mortem demonstrated necrotizing bronchitis and bronchiolitis with extensive areas of necrosis of the alveolar epithelium. Hyaline membranes were present in those cases with viral co-infection. Pulmonary blood vessels were filled with leukocytes without well-organized thrombi. Immunodepletion of the thymus, spleen, and lymph nodes was a common feature. Other organisms were isolated as follows; 2/10 cases Para influenza type 3, 2/10 Moraxella catarrhalis, 1/10 each with respiratory syncytial virus (RSV), a coliform organism, methicillin-resistant Staphylococcus aureus (MRSA), Haemophilus influenzae, Stenotrophomonas maltophilia, methicillin-sensitive Staphylococcus aureus (MSSA), and candida tropicalis. We postulate that severe hypoxemia and intractable cardiac failure may be due to the effects of pertussis toxin, necrotizing bronchiolitis, extensive damage to the alveolar epithelium, tenacious airway secretions, and possibly leukostasis with activation of the immunological cascade, all contributing to increased pulmonary vascular resistance. Cellular apoptosis appeared to underlay much of these changes. The secondary immuno-compromise may facilitate co-infection. PMID:19725100

Sawal, Mohammad; Cohen, Marta; Irazuzta, Jose E; Kumar, Ramani; Kirton, Christine; Brundler, Marie-Anne; Evans, Clair Anne; Wilson, John Andrew; Raffeeq, Parakkal; Azaz, Amer; Rotta, Alexandre T; Vora, Ajay; Vohra, Amit; Abboud, Patricia; Mirkin, L David; Cooper, Mehrengise; Dishop, Megan K; Graf, Jeanine M; Petros, Andy; Klonin, Hilary

2009-10-01

221

Identification of a series of tricyclic natural products as potent broad-spectrum inhibitors of metallo-beta-lactamases.  

PubMed

This work describes the discovery and characterization of a novel series of tricyclic natural product-derived metallo-beta-lactamase inhibitors. Natural product screening of the Bacillus cereus II enzyme identified an extract from a strain of Chaetomium funicola with inhibitory activity against metallo-beta-lactamases. SB236050, SB238569, and SB236049 were successfully extracted and purified from this extract. The most active of these compounds was SB238569, which possessed K(i) values of 79, 17, and 3.4 microM for the Bacillus cereus II, Pseudomonas aeruginosa IMP-1, and Bacteroides fragilis CfiA metallo-beta-lactamases, respectively, yet none of the compounds exhibited any inhibitory activity against the Stenotrophomonas maltophilia L-1 metallo-beta-lactamase (50% inhibitory concentration > 1,000 microM). The lack of activity against angiotensin-converting enzyme and serine beta-lactamases demonstrated the selective nature of these compounds. The crystal structure of SB236050 complexed in the active site of CfiA has been obtained to a resolution of 2.5 A. SB236050 exhibits key polar interactions with Lys184, Asn193, and His162 and a stacking interaction with the indole ring of Trp49 in the flap, which is in the closed conformation over the active site groove. SB236050 and SB238569 also demonstrate good antibacterial synergy with meropenem. Eight micrograms of SB236050 per ml gave rise to an eightfold drop in the MIC of meropenem for two clinical isolates of B. fragilis producing CfiA, making these strains sensitive to meropenem (MIC < or = 4 microg/ml). Consequently, this series of metallo-beta-lactamase inhibitors exhibit the most promising antibacterial synergy activity so far observed against organisms producing metallo-beta-lactamases. PMID:12019104

Payne, David J; Hueso-Rodríguez, Juan Antonio; Boyd, Helen; Concha, Néstor O; Janson, Cheryl A; Gilpin, Martin; Bateson, John H; Cheever, Christy; Niconovich, Nancy L; Pearson, Stewart; Rittenhouse, Stephen; Tew, David; Díez, Emilio; Pérez, Paloma; De La Fuente, Jesus; Rees, Michael; Rivera-Sagredo, Alfonso

2002-06-01

222

Molecular investigation of bacterial communities on the inner and outer surfaces of peripheral venous catheters.  

PubMed

Peripheral venous catheters (PVCs) are some of the most widely used medical devices in hospitals worldwide. PVC-related infections increase morbidity and treatment costs. The inner surfaces of PVCs are rarely examined for the population structure of bacteria, as it is generally believed that bacteria at this niche are similar to those on the external surface of PVCs. We primarily test this hypothesis and also study the effect of antibiotic treatment on bacterial communities from PVC surfaces. The inner and outer surfaces of PVCs from 15 patients were examined by 454 GS FLX Titanium 16S rRNA sequencing and the culture method. None of the PVCs were colonised according to the culture method and none of the patients had a bacteraemia. From a total of 127,536 high-quality sequence reads, 14 bacterial phyla and 268 diverse bacterial genera were detected. The number of operational taxonomic units for each sample was in the range of 86-157, even though 60 % of patients had received antibiotic treatment. Stenotrophomonas maltophilia was the predominant bacterial species in all the examined PVC samples. There were noticeable but not statistically significant differences between the inner and outer surfaces of PVCs in terms of the distribution of the taxonomic groups. In addition, the bacterial communities on PVCs from antibiotic-treated patients were significantly different from untreated patients. In conclusion, the surfaces of PVCs display complex bacterial communities. Although their significance has yet to be determined, these findings alter our perception of PVC-related infections. PMID:23529345

Zhang, L; Morrison, M; Nimmo, G R; Sriprakash, K S; Mondot, S; Gowardman, J R; George, N; Marsh, N; Rickard, C M

2013-03-26

223

Rapid screening and cultivation of oleaginous microorganisms.  

PubMed

Oleaginous microbial strains were cultivated to identify the best oil-producing strain amongst Yarrowia lipolytica (CGMCC 2.1398), Lipomyces starkeyi (CGMCC 2.1608), Rhodosporidium toruloides (CGMCC 2.1389), Mortierella isabellina (CGMCC 3.3410), Cunninghamella blakeleana (CGMCC 3.970), and Mycobacterium QJ311. A method for rapid determination of oil content and fatty acid composition was established to identify the optimum oil-producing strains. This method had a relative standard deviation of 4.09%, an average recovery ratio of 97.09% and a detection limit of 0.1-1.0 g. Mortierella isabellina CGMCC 3.3410 was identified as the best oil-producing strain amongst the six strains tested, with a total biomass of 75 g/10 L and a lipid content of 35%. A rapid screening method of oleaginous microorganisms is discussed for the first time. PMID:22611917

Gao, Xinlei; Liu, Ye; Che, Zhongju; Wu, Li

2012-04-01

224

Epidemiology of bacteremia caused by uncommon non-fermentative gram-negative bacteria.  

PubMed

BACKGROUND: Prevalence of bacteremia caused by non-fermentative gram-negative bacteria (NFGNB) has been increasing over the past decade. Although many studies have already investigated epidemiology of NFGNB bacteremia, most focused only on common NFGNB including Pseudomonas aeruginosa (PA) and Acinetobacter baumannii (AB). Knowledge of uncommon NFGNB bacteremia is very limited. Our study aimed to investigate epidemiology and identify factors associated with uncommon NFGNB bacteremia. METHODS: This observational study was conducted at a university hospital in Thailand during July 1, 2007-Dec 31, 2008. All patients who had at least one blood culture positive for NFGNB and met the criteria for systemic inflammatory response syndrome within 24 hours before/after obtaining the blood culture were enrolled. The NFGNB isolates that could not be satisfactorily identified by the standard biochemical assays were further characterized by molecular sequencing methods. To identify factors associated with uncommon NFGNB bacteremia, characteristics of patients in the uncommon NFGNB group were subsequently compared to patients in the common NFGNB group (AB and PA bacteremia). RESULTS: Our study detected 223 clinical isolates of NFGNB in 221 unique patients. The major causative pathogens were AB (32.7%), followed by PA (27.8%), Stenotrophomonas maltophilia (5.4%), Acinetobacter lwoffii (4.9%) and Burkholderia pseudomallei (2.7%). Infection-related mortality was 63.0% in the AB group, 40.3% in the PA group and 17.4% in the uncommon NFGNB group. Factors associated with uncommon NFGNB bacteremia (OR [95%CI];p-value) were male sex (0.28[0.14-0.53];p < 0.001), hospital-acquired infection (0.23[0.11-0.51];p < 0.001), recent aminoglycosides exposure 0.23[0.06-0.8];p = 0.01), primary bacteremia (6.43[2.89-14.2];p < 0.001]), catheter related infection (4.48[1.54-13.06];p < 0.001) and recent vancomycin exposure (3.88[1.35-11.1];p = 0.02). CONCLUSIONS: Our distribution of causative pathogens was slightly different from other studies. The common NFGNB group had a remarkably higher ID-mortality than the uncommon NFGNB group. Knowledge of factors associated with uncommon NFGNB bacteremia would help physicians to distinguish between low vs. high risk patients. PMID:23566113

Rattanaumpawan, Pinyo; Ussavasodhi, Prapassorn; Kiratisin, Pattarachai; Aswapokee, Nalinee

2013-04-01

225

[Investigation of antibacterial activity of sertralin].  

PubMed

Sertralin is a psychotropic drug which acts by inhibiting the selective serotonin re-uptake in the synaptic area. Previous studies have shown that some antidepressant agents have antibacterial activity. The aim of this study was to investigate the in vitro antibacterial activity of sertralin. A total of 224 bacterial strains isolated from clinical specimens together with standard control strains were included to the study. The antibacterial activity of sertralin was determined by microdilution method in Mueller-Hinton broth according to the Clinical and Laboratory Standards Institute (CLSI) guideline. The minimum inhibitory concentration (MIC) values were found to be 4-32 microg/ml for 22 methicillin-susceptible Staphylococcus aureus strains, 16-32 microg/ml for 25 methicillin-resistant S. aureus strains, 8-32 microg/ml for 20 methicillin-resistant coagulase-negative staphylococci strains, 16-32 microg/ml for 4 vancomycin-susceptible Enterococcus faecalis strains, 0.5-32 microg/ml for 10 vancomycin-susceptible Enterococcus faecium strains, 2-8 microg/ml for 12 vancomycin-resistant E. faecium strains, 16-128 microg/ml for 21 Acinetobacter baumannii strains, 4->128 microg/ml for 20 Klebsiella pneumoniae strains, 0.25-128 microg/ml for 24 Escherichia coil strains, 64->128 microg/ml for 22 Pseudomonas aeruginosa strains, 128->128 microg/ml for 2 Proteus vulgaris strains, 64->128 microg/ml for 8 Proteus mirabilis strains, 32->128 microg/ml for 7 Stenotrophomonas maltophilia strains, 32-128 microg/ml for 21 Enterobacter cloacae strains and 8-128 microg/ml for 6 Enterobacter aerogenes strains. The MIC values of sertralin against standard strains were as follows; 16 microg/ml for S. aureus ATCC 29213 (methicillin-susceptible), 32 microg/ml for S. aureus ATCC 43300 (methicillin-resistant), 16 microg/ml for E. faecalis ATCC 29212, 32 microg/ml for K. pneumoniae ATCC 700603, 32 microg/ml for E. coli ATCC 25922 and > 128 microg/ml for P. aeruginosa ATCC 27853. Sertralin has showed antibacterial activity mainly against gram-positive bacteria, and it was surprising that MIC values of vancomycin-resistant enterococci were lower than those of vancomycin-susceptible ones. Further in vivo and in vitro studies are required to provide reliable data about the use of sertralin as an adjuvant agent in the antibacterial treatment of infections caused by multidrug-resistant bacteria. PMID:20084919

Coban, Ahmet Yilmaz; Tanriverdi Cayci, Yeliz; Kele? Uluda?, Selma; Durupinar, Belma

2009-10-01

226

The antimicrobial efficacy of silver on antibiotic-resistant bacteria isolated from burn wounds.  

PubMed

The antibiotic-resistant bacteria are a major concern to wound care because of their ability to resist many of the antibiotics used today to treat infections. Consequently, other antimicrobials, in particular ionic silver, are considered ideal topical agents for effectively helping to manage and prevent local infections. Little is known about the antimicrobial efficacy of ionic silver on antibiotic-resistant bacteria at different pH values. Consequently, in this study our aim was to evaluate the effect of pH on the antimicrobial efficacy of a silver alginate (SA) and a silver carboxymethyl cellulose (SCMC) dressing on antibiotic-resistant bacteria isolated from burn patients. Forty-nine antibiotic-resistant bacteria, including Vancomycin-resistant Enterococcus faecium, meticillin-resistant Staphylococcus aureus, multidrug-resistant (MDR) Pseudomonas aeruginosa, MDR Vibrio sp, MDR Stenotrophomonas maltophilia, extended-spectrum ß-lactamase (ESBL) producing Salmonella sp, ESBL producing Klebsiella pneumoniae, ESBL producing Proteus mirabilis, ESBL producing Escherichia coli and MDR Acinetobacter baumannii, routinely isolated from burn wounds were used in the study and evaluated for their susceptibility to two silver containing wound dressings using a standardised antimicrobial efficacy screening assay [corrected zone of inhibition (CZOI)]. The mean overall CZOI for the Gram-positive isolates at a pH of 5·5 were very similar for both dressings. A mean CZOI of 5 mm was recorded for the SCMC dressing, which was slightly higher, at 5·4 mm for the SA dressing. At a pH of 7·0 both dressings, in general, showed a similar activity. However, at a pH of 8·5 the mean CZOI of the SCMC dressing was found to be significantly (P < 0·05) higher than the SA dressing for a select number of isolates. The mean overall CZOI for the Gram-negative bacteria followed a similar pattern as observed with the Gram-positive bacteria. Susceptibility to silver ions did vary significantly between genera and species of bacteria. Interestingly, when pH was changed from 8·5 to 5·5 antimicrobial activity for both dressings in general increased significantly (P < 0·05). Overall, all forty-nine antibiotic-resistant bacteria isolated from burn wounds showed susceptibility to the antimicrobial activity of both silver containing wound dressings over all pH ranges. In addition, the study showed that the performance of both dressings apparently increased when pH became more acidic. The findings in this study may help to further enhance our knowledge of the role pH plays in affecting both bacterial susceptibility and antimicrobial activity of silver containing wound dressings. PMID:22182219

Percival, Steven L; Thomas, John; Linton, Sara; Okel, Tyler; Corum, Linda; Slone, Will

2011-12-19

227

Combination of chromogenic differential medium and estA-specific PCR for isolation and detection of phytopathogenic Xanthomonas spp.  

PubMed

A xanthomonad differential medium (designated Xan-D medium) was developed, on which streaks and colonies of xanthomonads, including 13 species of the genus Xanthomonas, turned wet-shining yellow-green and were surrounded with a smaller milky zone and a bigger clear zone in 3 to 4 days. The characteristics could easily be differentiated from those of yellow nonxanthomonads and other bacteria. The mechanism of color change and formation of a milky zone on the medium are mainly due to the Tween 80 hydrolytic capacity of xanthomonads. The gene, estA, responsible for Tween 80 hydrolysis was cloned and expressed in Escherichia coli, which acquired a capacity to hydrolyze Tween 80 and could turn green and form a milky zone on the Xan-D medium. The nucleotide sequence of estA is highly conserved in the xanthomonads, and the sequence was used to design a specific PCR primer set. The PCR amplification using the primer set amplified a 777-bp specific DNA fragment for all xanthomonad strains tested. The Xan-D medium was used to isolate and differentiate Xanthomonas campestris pv. campestris from naturally infected cabbages with black rot symptoms for a rapid diagnosis. All isolated X. campestris pv. campestris strains developed characteristic colonies and were positive in the PCR with the estA primer set. The Xan-D medium was further amended with antibiotics and successfully used for the detection of viable X. campestris pv. campestris cells from plant seeds. Although some yellow nonxanthomonads and other saprophytic bacteria from plant seeds could still grow on the medium, they did not interfere with the color development of X. campestris pv. campestris. However, Stenotrophomonas maltophilia, which is closely related to xanthomonads, existing in a seed lot could also develop yellow-green color but had different colony morphology and was negative in the PCR with the estA primer set. Accordingly, the combination of the Xan-D medium with the estA-specific PCR is a useful and reliable method for the isolation and detection of viable xanthomonad cells from plant materials. PMID:19749062

Lee, Yung-An; Sung, Ai-Ning; Liu, Tzu-Fen; Lee, Yung-Shan

2009-09-11

228

Interactions of ?-Lactamases with Sanfetrinem (GV 104326) Compared to Those with Imipenem and with Oral ?-Lactams  

PubMed Central

Sanfetrinem is a trinem ?-lactam which can be administered orally as a hexatil ester. We examined whether its ?-lactamase interactions resembled those of the available carbapenems, i.e., stable to AmpC and extended-spectrum ?-lactamases but labile to class B and functional group 2f enzymes. The comparator drugs were imipenem, oral cephalosporins, and amoxicillin. MICs were determined for ?-lactamase expression variants, and hydrolysis was examined directly with representative enzymes. Sanfetrinem was a weak inducer of AmpC ?-lactamases below the MIC and had slight lability, with a kcat of 0.00033 s?1 for the Enterobacter cloacae enzyme. Its MICs for AmpC-derepressed E. cloacae and Citrobacter freundii were 4 to 8 ?g/ml, compared with MICs of 0.12 to 2 ?g/ml for AmpC-inducible and -basal strains; MICs for AmpC-derepressed Serratia marcescens and Morganella morganii were not raised. Cefixime and cefpodoxime were more labile than sanfetrinem to the E. cloacae AmpC enzyme, and AmpC-derepressed mutants showed much greater resistance; imipenem was more stable and retained full activity against derepressed mutants. Like imipenem, sanfetrinem was stable to TEM-1 and TEM-10 enzymes and retained full activity against isolates and transconjugants with various extended-spectrum TEM and SHV enzymes, whereas these organisms were resistant to cefixime and cefpodoxime. Sanfetrinem, like imipenem and cefixime but unlike cefpodoxime, also retained activity against Proteus vulgaris and Klebsiella oxytoca strains that hyperproduced potent chromosomal class A ?-lactamases. Functional group 2f enzymes, including Sme-1, NMC-A, and an unnamed enzyme from Acinetobacter spp., increased the sanfetrinem MICs by up to 64-fold. These enzymes also compromised the activities of imipenem and amoxicillin but not those of the cephalosporins. The hydrolysis of sanfetrinem was examined with a purified Sme-1 enzyme, and biphasic kinetics were found. Finally, zinc ?-lactamases, including IMP-1 and the L1 enzyme of Stenotrophomonas maltophilia, conferred resistance to sanfetrinem and all other ?-lactams tested, and hydrolysis was confirmed with the IMP-1 enzyme. We conclude that sanfetrinem has ?-lactamase interactions similar to those of the available carbapenems except that it is a weaker inducer of AmpC types, with some tendency to select derepressed mutants, unlike imipenem and meropenem.

Babini, Gioia S.; Yuan, Meifang; Livermore, David M.

1998-01-01

229

Isolation and characterization of novel iron-oxidizing bacteria that grow at circumneutral pH.  

PubMed Central

A gel-stabilized gradient method that employed opposing gradients of Fe2+ and O2 was used to isolate and characterize two new Fe-oxidizing bacteria from a neutral pH, Fe(2+)-containing groundwater in Michigan. Two separate enrichment cultures were obtained, and in each the cells grew in a distinct, rust-colored band in the gel at the oxic-anoxic interface. The cells were tightly associated with the ferric hydroxides. Repeated serial dilutions of both enrichments resulted in the isolation of two axenic strains, ES-1 and ES-2. The cultures were judged pure based on (i) growth from single colonies in tubes at dilutions of 10(-7) (ES-2) (ES-2) and 10(-8) (ES-1); (ii) uniform cell morphologies, i.e., ES-1 was a motile long thin, bent, or S-shaped rod and ES-2 was a shorter curved rod; and (iii) no growth on a heterotrophic medium. Strain ES-1 grew to a density of 10(8) cells/ml on FeS with a doubling time of 8 h. Strain ES-2 grew to a density of 5 x 10(7) cells/ml with a doubling time of 12.5 h. Both strains also grew on FeCO3. Neither strain grew without Fe2+, nor did they grow with glucose, pyruvate, acetate, Mn, or H2S as an electron donor. Studies with an oxygen microelectrode revealed that both strains grew at the oxic-anoxic interface of the gradients and tracked the O2 minima when subjected to higher O2 concentrations, suggesting they are microaerobes. Phylogenetically the two strains formed a novel lineage within the gamma Proteobacteria. They were very closely related to each other and were equally closely related to PVB OTU 1, a phylotype obtained from an iron-rich hydrothermal vent system at the Loihi Seamount in the Pacific Ocean, and SPB OTU 1, a phylotype obtained from permafrost soil in Siberia. Their closest cultivated relative was Stenotrophomonas maltophilia. In total, this evidence suggests ES-1 and ES-2 are members of a previously untapped group of putatively lithotrophic, unicellular iron-oxidizing bacteria.

Emerson, D; Moyer, C

1997-01-01

230

Isolation and Characterization of a Virulent Bacteriophage AB1 of Acinetobacter baumannii  

PubMed Central

Background Acinetobacter baumannii is an emerging nosocomial pathogen worldwide with increasing prevalence of multi-drug and pan-drug resistance. A. baumannii exists widely in natural environment, especially in health care settings, and has been shown difficult to be eradicated. Bacteriophages are often considered alternative agent for controlling bacterial infection and contamination. In this study, we described the isolation and characterization of one virulent bacteriophage AB1 capable of specifically infecting A. baumannii. Results A virulent bacteriophage AB1, specific for infecting a clinical strain A. baumannii KD311, was first isolated from marine sediment sample. Restriction analysis indicated that phage AB1 was a dsDNA virus with an approximate genome size of 45.2 kb to 46.9 kb. Transmission electron microscopy showed that phage AB1 had an icosahedral head with a non-contractile tail and collar or whisker structures, and might be tentatively classified as a member of the Siphoviridae family. Proteomic pattern of phage AB1, generated by SDS-PAGE using purified phage particles, revealed five major bands and six minor bands with molecular weight ranging from 14 to 80 kilo-dalton. Also determined was the adsorption rate of phage AB1 to the host bacterium, which was significantly enhanced by addition of 10 mM CaCl2. In a single step growth test, phage AB1 was shown having a latent period of 18 minutes and a burst size of 409. Moreover, pH and thermal stability of phage AB1 were also investigated. At the optimal pH 6.0, 73.2% of phages survived after 60 min incubation at 50°C. When phage AB1 was used to infect four additional clinical isolates of A. baumannii, one clinical isolate of Stenotrophomonas maltophilia, and Pseudomonas aeruginosa lab strains PAK and PAO1, none of the tested strains was found susceptible, indicating a relatively narrow host range for phage AB1. Conclusion Phage AB1 was capable of eliciting efficient lysis of A. baumannii, revealing its potential as a non-toxic sanitizer for controlling A. baumannii infection and contamination in both hospital and other public environments.

2010-01-01

231

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

232

Cryobacterium levicorallinum sp. nov., a psychrophilic bacterium isolated from glacier ice.  

PubMed

In this study, two psychrophilic bacterial strains were isolated from the China No. 1 glacier in Xinjiang, north-west China. Cells were Gram-positive rods. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the strains belonged to the genus Cryobacterium. Phylogenetic analysis showed that they clustered together and are most closely related to Cryobacterium luteum CGMCC 1.11210(T), Cryobacterium flavum CGMCC 1.11215(T), Cryobacterium psychrophilum CGMCC 1.4292(T), Cryobacterium psychrotolerans CGMCC 1.5382(T) and Cryobacterium roopkundense CGMCC 1.10672(T). The major cellular fatty acids of the novel strains were anteiso-C15?:?0, anteiso-C15 : 1 A, iso-C16 : 0 and iso-C15 : 0. Both strains contained diphosphatidylglycerol, phosphatidylglycerol and one unidentified glycolipid in the cell membrane. The results of DNA-DNA hybridization and physiological tests allowed the genotypic and phenotypic differentiation of strains Hh34(T) and Hh28 from related species. However, their high DNA-DNA relatedness showed that they belong to the same novel species. Strain Hh34(T) (= NBRC 107883(T) = CGMCC 1.11211(T)) was selected as the type strain to represent this novel species, for which the name Cryobacterium levicorallinum sp. nov. is proposed. PMID:23315411

Liu, Qing; Liu, Hongcan; Zhang, Jianli; Zhou, Yuguang; Xin, Yuhua

2013-01-11

233

Genetic Basis of Long-Chain Aliphatic Hydrocarbon Biosynthesis in Bacteria. Final Technical Report, July 7, 1981-January 6, 1983.  

National Technical Information Service (NTIS)

A variety of Micrococcus species, some related Arthrobacter, and Pseudomonas maltophilia are among the few bacteria which produce significant quantities of long chain aliphatic hydrocarbons. It was the purpose of this investigation to initiate studies aim...

W. E. Kloos

1983-01-01

234

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 ...

235

Analysis of Bacterial Community Structure in Sulfurous-Oil-Containing Soils and Detection of Species Carrying Dibenzothiophene Desulfurization (dsz) Genes  

PubMed Central

The selective effects of sulfur-containing hydrocarbons, with respect to changes in bacterial community structure and selection of desulfurizing organisms and genes, were studied in soil. Samples taken from a polluted field soil (A) along a concentration gradient of sulfurous oil and from soil microcosms treated with dibenzothiophene (DBT)-containing petroleum (FSL soil) were analyzed. Analyses included plate counts of total bacteria and of DBT utilizers, molecular community profiling via soil DNA-based PCR-denaturing gradient gel electrophoresis (PCR-DGGE), and detection of genes that encode enzymes involved in the desulfurization of hydrocarbons, i.e., dszA, dszB, and dszC.Data obtained from the A soil showed no discriminating effects of oil levels on the culturable bacterial numbers on either medium used. Generally, counts of DBT degraders were 10- to 100-fold lower than the total culturable counts. However, PCR-DGGE showed that the numbers of bands detected in the molecular community profiles decreased with increasing oil content of the soil. Analysis of the sequences of three prominent bands of the profiles generated with the highly polluted soil samples suggested that the underlying organisms were related to Actinomyces sp., Arthrobacter sp., and a bacterium of uncertain affiliation. dszA, dszB, and dszC genes were present in all A soil samples, whereas a range of unpolluted soils gave negative results in this analysis. Results from the study of FSL soil revealed minor effects of the petroleum-DBT treatment on culturable bacterial numbers and clear effects on the DBT-utilizing communities. The molecular community profiles were largely stable over time in the untreated soil, whereas they showed a progressive change over time following treatment with DBT-containing petroleum. Direct PCR assessment revealed the presence of dszB-related signals in the untreated FSL soil and the apparent selection of dszA- and dszC-related sequences by the petroleum-DBT treatment. PCR-DGGE applied to sequential enrichment cultures in DBT-containing sulfur-free basal salts medium prepared from the A and treated FSL soils revealed the selection of up to 10 distinct bands. Sequencing a subset of these bands provided evidence for the presence of organisms related to Pseudomonas putida, a Pseudomonas sp., Stenotrophomonas maltophilia, and Rhodococcus erythropolis. Several of 52 colonies obtained from the A and FSL soils on agar plates with DBT as the sole sulfur source produced bands that matched the migration of bands selected in the enrichment cultures. Evidence for the presence of dszB in 12 strains was obtained, whereas dszA and dszC genes were found in only 7 and 6 strains, respectively. Most of the strains carrying dszA or dszC were classified as R. erythropolis related, and all revealed the capacity to desulfurize DBT. A comparison of 37 dszA sequences, obtained via PCR from the A and FSL soils, from enrichments of these soils, and from isolates, revealed the great similarity of all sequences to the canonical (R. erythropolis strain IGTS8) dszA sequence and a large degree of internal conservation. The 37 sequences recovered were grouped in three clusters. One group, consisting of 30 sequences, was minimally 98% related to the IGTS8 sequence, a second group of 2 sequences was slightly different, and a third group of 5 sequences was 95% similar. The first two groups contained sequences obtained from both soil types and enrichment cultures (including isolates), but the last consisted of sequences obtained directly from the polluted A soil.

Duarte, Gabriela Frois; Rosado, Alexandre Soares; Seldin, Lucy; de Araujo, Welington; van Elsas, Jan Dirk

2001-01-01

236

Bacterial diversity, organic pollutants and their metabolites in two aeration lagoons of common effluent treatment plant (CETP) during the degradation and detoxification of tannery wastewater  

Microsoft Academic Search

In this study, PCR-RFLP and GC–MS approaches were used to characterize the bacterial diversity, organic pollutants and metabolites during the tannery wastewater treatment process at common effluent treatment plant (CETP). Results revealed that the bacterial communities growing in aeration lagoon-I were dominated with Escherichia sp., Stenotrophomonas sp., Bacillus sp. and Cronobacter sp. while that of aeration lagoon-II prevailed with Stenotrophomonas

Ram Chandra; Ram Naresh Bharagava; Atya Kapley; Hemant J. Purohit

2011-01-01

237

Draft Genome Sequence of Bacillus cereus Strain LCT-BC244  

PubMed Central

Bacillus cereus is a prevalent, soil-dwelling, Gram-positive bacterium. Some strains are harmful to humans and cause food-borne illness, while other strains can be beneficial as probiotics for animals. To gain insight into the bacterial genetic determinants, we report the genome sequence of a strain, LCT-BC244, which was isolated from CGMCC 1.230.

Su, Longxiang; Zhou, Tao; Zhou, Lisha; Fang, Xiangqun; Li, Tianzhi; Wang, Junfeng; Guo, Yinghua; Chang, De; Wang, Yajuan

2012-01-01

238

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.

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

2012-01-01

239

Draft Genome Sequence of Serratia marcescens Strain LCT-SM213  

PubMed Central

Serratia marcescens is a species of Gram-negative, rod-shaped bacterium of the family Enterobacteriaceae. S. marcescens can cause nosocomial infections, particularly catheter-associated bacteremia, urinary tract infections, and wound infections. Here, we present the draft genome sequence of Serratia marcescens strain LCT-SM213, which was isolated from CGMCC 1.1857.

Wang, Yajuan; Yuan, Yanting; Zhou, Lisha; Su, Qingqing; Fang, Xiangqun; Li, Tianzhi; Wang, Junfeng; Chang, De; Su, Longxiang; Xu, Guogang; Guo, Yinghua

2012-01-01

240

Genetic basis of long-chain aliphatic hydrocarbon biosynthesis in bacteria. Final technical report, July 7, 1981January 6, 1983  

Microsoft Academic Search

A variety of Micrococcus species, some related Arthrobacter, and Pseudomonas maltophilia are among the few bacteria which produce significant quantities of long chain aliphatic hydrocarbons. It was the purpose of this investigation to initiate studies aimed at understanding the genetic basis of aliphatic hydrocarbon production. Results have shown that some strains of several of the Micrococcus species carry plasmids, but

Kloos

1983-01-01

241

Genetic and Biochemical Characterization of the Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) Synthase in Haloferax mediterranei  

Microsoft Academic Search

The haloarchaeon Haloferax mediterranei has shown promise for the economical production of poly(3- hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), a desirable bioplastic. However, little is known at present about the genes involved in PHBV synthesis in the domain Archaea. In this study, we cloned the gene cluster (phaECHme) encoding a polyhydroxyalkanoate (PHA) synthase in H. mediterranei CGMCC 1.2087 via thermal asymmetric interlaced PCR. Western

Qiuhe Lu; Jing Han; Ligang Zhou; Jian Zhou; Hua Xiang

2008-01-01

242

Economical succinic acid production from cane molasses by Actinobacillus succinogenes  

Microsoft Academic Search

In this work, production of succinic acid by Actinobacillus succinogenes CGMCC1593 using cane molasses as a low cost carbon source was developed. In anaerobic bottles fermentation, succinic acid concentration of 50.6±0.9gl?1 was attained at 60h using an optimum medium containing molasses pretreated with sulfuric acid, resulting in a succinic acid yield of 79.5±1.1% and sugar utilization of 97.1±0.6%. When batch

Yu-Peng Liu; Pu Zheng; Zhi-Hao Sun; Ye Ni; Jin-Jun Dong; Lei-Lei Zhu

2008-01-01

243

Proposal to reclassify the Streptomyces albidoflavus clade on the basis of multilocus sequence analysis and DNA–DNA 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

244

Biotransformation of steriodal saponins in Dioscorea zingiberensis C. H. Wright to diosgenin by Trichoderma harzianum  

Microsoft Academic Search

Diosgenin is an important starting material in the steroidal hormone industry. Traditionally, diosgenin is mainly produced\\u000a by acid hydrolysis of Dioscorea zingiberensis C. H. Wright (DZW) tubers. This method yields numerous byproducts that can cause serious pollution. In this study, diosgenin\\u000a was obtained by biotransformation of steroidal saponins in DZW afforded by Trichoderma harzianum CGMCC 2979. The medium was optimized

Lin Liu; Yue-Sheng Dong; Shan-Shan Qi; Hui Wang; Zhi-Long Xiu

2010-01-01

245

Identification of fengycin homologues from Bacillus subtilis with ESI-MS\\/CID  

Microsoft Academic Search

Bacillus subtilis fmbJ (CGMCC no.0943) was used to produce lipopeptides antibiotics fengycin. The fengycin mixture was precipitated with 6N HCl and extracted by methanol. Electrospray ionization mass spectrometry\\/collision-induced dissociation (ESI-MS\\/CID) were used to analyze the fengycin mixture. In the ESI-MS\\/CID spectra of fengycin molecular ions, production ions (m\\/z 1080, m\\/z 966, m\\/z 1108 and m\\/z 994) were always detected. Therefore,

Xiaomei Bie; Zhaoxin Lu; Fengxia Lu

2009-01-01

246

Succession and growth strategy of a spring microbial community from kezhou sinter in china  

PubMed Central

The succession and growth strategy of a spring microbial community under earthquake action were investigated. The majority of pre-earthquake isolates belonged to the Gammaproteobacteria, including two numerically dominant Stenotrophomonas sp. RB25 and Acinetobacter sp. RB11 (r-strategists). The predominant post-earthquake isolates were Alphaproteobacteria, with Rhizobium sp. RA42 (K-strategists) being dominant among these organisms.

Yang, Hongmei; Lou, Kai

2011-01-01

247

Simultaneous degradation of the pesticides methyl parathion and chlorpyrifos by an isolated bacterial consortium from a contaminated site  

Microsoft Academic Search

The simultaneous degradation of the pesticide methyl parathion and chlorpyrifos was tested using a bacterial consortium obtained by selective enrichment from highly contaminated soils in Moravia (Medellin, Colombia). Microorganisms identified in the consortium were 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. In

Nancy Pino; Gustavo Peñuela

2011-01-01

248

Carbapenem-based prodrugs. Design, synthesis, and biological evaluation of carbapenems.  

PubMed

Syntheses of racemic trans-3-hydroxycarbonyl-6-(phenylacetamido)carbapenem (13), trans-3-phosphono-6-(phenylacetamido)carbapenem (17), and beta-lactam based prodrugs 19 and 22 were accomplished. Carbapenem 13 was found to possess antibacterial activity, comparable with imipenem (+)-3, against Staphylococcus aureus FDA 209P, S. aureus 95, Escherichia coli ATCC 39188, Klebsiella pneumoniae NCTC 418, Pseudomonas aeruginosa 1101-75, P. aeruginosa 18S-H, and Xanthomonas maltophilia GN 12873. Like imipenem ((+)-3), carbapenem 13 was not stable to X. maltophilia oxyiminocephalosporinase type II. Its phosphonate analog 17, however, was neither a significant antibacterial agent nor a good beta-lactamase inhibitor. Chemical combinations of trans carbapenem 13 with cis carbapenem 6 (compound 19) as well as clavulanic acid (20) with cis carbapenem 6 (compound 22) via a tetrachloroethane linker exhibited remarkable activity against beta-lactamase producing microorganisms in vitro. PMID:15804533

Hakimelahi, Gholam Hossein; Moosavi-Movahedi, Ali Akbar; Saboury, Ali Akbar; Osetrov, Valeriy; Khodarahmi, Ghadam Ali; Shia, Kak-Shan

2005-01-20

249

Studies on the microflora associated with xenic cultures of Entamoeba gingivalis.  

PubMed

The microflora associated with xenic stock cultures (ATCC 30927) of Entamoeba gingivalis, the major protozoan of the human oral cavity, were isolated and identified as Citrobacter diversus, Yersinia enterocolitica, Acinetobacter anitratus and Pseudomonas maltophilia. In studies to determine whether the bacterial isolates were able to utilize rice starch as a sole carbon source, Y. enterocolitica exhibited excellent growth in rice starch minimal medium and TYSGM-9 medium (with rice starch), but growth was weak in TYSGM-9 medium (without rice starch). C. diversus, A. anitratus and P. maltophilia exhibited poor growth in rice starch minimal medium, but they produced excellent growth in TYSGM-9 medium with or without rice starch. In order to determine the effect of the rice starch hydrolysis on Entamoeba growth, the filtrate from each isolate grown in rice starch minimal medium was added to an E. gingivalis culture grown in TYSGM-9 medium. The filtrate from a Y. enterocolitica culture grown in rice starch minimal medium enhanced E. gingivalis growth, but the filtrates from cultures of C. diversus, A. anitratus and P. maltophilia suppressed E. gingivalis growth. This supported the concept that Y. enterocolitica is capable of metabolizing rice starch into intermediate products, which in turn can be utilized by the amoeba. PMID:2739589

Gannon, J T; Linke, H A

1989-01-01

250

Diversity of bacterial endophytes in roots of Mexican husk tomato plants (Physalis ixocarpa) and their detection in the rhizosphere.  

PubMed

Endophytic bacterial diversity was estimated in Mexican husk tomato plant roots by amplified rDNA restriction analysis and sequence homology comparison of the 16S rDNA genes. Sixteen operational taxonomic units from the 16S rDNA root library were identified based on sequence analysis, including the classes Gammaproteobacteria, Betaproteobacteria, Actinobacteria, and Bacilli. The predominant genera were Stenotrophomonas (21.9%), Microbacterium (17.1%), Burkholderia (14.3%), Bacillus (14.3%), and Pseudomonas (10.5%). In a 16S rDNA gene library of the same plant species' rhizosphere, only common soil bacteria, including Stenotrophomonas, Burkholderia, Bacillus, and Pseudomonas, were detected. We suggest that the endophytic bacterial diversity within the roots of Mexican husk tomato plants is a subset of the rhizosphere bacterial population, dominated by a few genera. PMID:21157706

Marquez-Santacruz, H A; Hernandez-Leon, R; Orozco-Mosqueda, M C; Velazquez-Sepulveda, I; Santoyo, G

2010-12-07

251

Conjugative transfer of preferential utilization of aromatic compounds from Pseudomonas putida CSV86  

Microsoft Academic Search

Pseudomonas putida CSV86 utilizes naphthalene (Nap), salicylate (Sal), benzyl alcohol (Balc), and methylnaphthalene (MN) preferentially over\\u000a glucose. Methylnaphthalene is metabolized by ring-hydroxylation as well as side-chain hydroxylation pathway. Although the\\u000a degradation property was found to be stable, the frequency of obtaining Nap?Sal?MN?Balc? phenotype increased to 11% in the presence of curing agents. This property was transferred by conjugation to Stenotrophomonas

Aditya Basu; Prashant S. Phale

2008-01-01

252

Adhesion Mechanisms of Plant-Pathogenic Xanthomonadaceae  

Microsoft Academic Search

\\u000a The family Xanthomonadaceae is a wide-spread family of bacteria belonging to the gamma subdivision of the Gram-negative proteobacteria, including the\\u000a two plant-pathogenic genera Xanthomonas and Xylella, and the related genus Stenotrophomonas. Adhesion is a widely conserved virulence mechanism among Gram-negative bacteria, no matter whether they are human, animal\\u000a or plant pathogens, since attachment to the host tissue is one of

Nadia Mhedbi-Hajri; Marie-Agnès Jacques; Ralf Koebnik

253

Paenibacillus —a predominant endophytic bacterium colonising tissue cultures of woody plants  

Microsoft Academic Search

High densities of endophytic bacteria were found in plant material from poplar, larch and spruce that had been micropropagated\\u000a for at least 5 years. The majority of these bacteria were assigned to the genus Paenibacillus based on the sequencing of the 16S rRNA genes. Other endophytic bacteria such as Methylobacterium, Stenotrophomonas or Bacillus could also be found but only in some

Kristina Ulrich; Thomas Stauber; Dietrich Ewald

2008-01-01

254

Biodegradation of Indeno (1,2,3-cd) Pyrene by a Pure Bacterial Culture of Pandoraea sp  

Microsoft Academic Search

Three new isolated bacterial cultures of Pandoraea sp., Stenotrophomonas sp., and T Pseudoxanthomonas mexicana that could efficiently degraded Indeno (1,2,3-cd) pyrene (Inp) were reported in this paper. The biodegradation performance of Inp by Pandoraea sp was studied under different pH conditions. Under the conditions of pH=8, the removal efficiency of Inp fluctuated sharply among 8% and 40%. The optimal condition

Yongchao Du; Junfeng Dou; Lirong Cheng; Aizhong Ding; Fuqiang Fan; Haiying Chen

2010-01-01

255

Genetic and Biochemical Characterization of the Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) Synthase in Haloferax mediterranei? †  

PubMed Central

The haloarchaeon Haloferax mediterranei has shown promise for the economical production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), a desirable bioplastic. However, little is known at present about the genes involved in PHBV synthesis in the domain Archaea. In this study, we cloned the gene cluster (phaECHme) encoding a polyhydroxyalkanoate (PHA) synthase in H. mediterranei CGMCC 1.2087 via thermal asymmetric interlaced PCR. Western blotting revealed that the phaEHme and phaCHme genes were constitutively expressed, and both the PhaEHme and PhaCHme proteins were strongly bound to the PHBV granules. Interestingly, CGMCC 1.2087 could synthesize PHBV in either nutrient-limited medium (supplemented with 1% starch) or nutrient-rich medium, up to 24 or 18% (wt/wt) in shaking flasks. Knockout of the phaECHme genes in CGMCC 1.2087 led to a complete loss of PHBV synthesis, and only complementation with the phaECHme genes together (but not either one alone) could restore to this mutant the capability for PHBV accumulation. The known haloarchaeal PhaC subunits are much longer at their C termini than their bacterial counterparts, and the C-terminal extension of PhaCHme was proven to be indispensable for its function in vivo. Moreover, the mixture of purified PhaEHme/PhaCHme (1:1) showed significant activity of PHA synthase in vitro. Taken together, our results indicated that a novel member of the class III PHA synthases, composed of PhaCHme and PhaEHme, accounted for the PHBV synthesis in H. mediterranei.

Lu, Qiuhe; Han, Jing; Zhou, Ligang; Zhou, Jian; Xiang, Hua

2008-01-01

256

Gracilibacillus marinus sp. nov., isolated from the northern South China Sea.  

PubMed

Two gram-positive, aerobic, spore-forming, rod-shaped bacteria, designated HB09003(T) and HB12160, were isolated from seawater and sediment in the northern South China Sea, respectively. Cells were found to be motile by means of peritrichous flagella. The strains were found to grow with 0-15 % (w/v) NaCl, at 10-45 °C and pH 5.0-10.7, with an optimum of 3 % NaCl, 28 °C and pH 8.5, respectively. The predominant isoprenoid quinone of strain HB09003(T), selected as the representative strain, was identified as MK-7. This strain was found to possess anteiso-C15:0, iso-C15:0, anteiso-C17:0 and C16:0 as the major fatty acids. The G+C contents of strain HB09003(T) and HB12160 were determined to be 34.1 and 34.3 mol%, respectively. Analysis of the 16S rRNA gene sequences of the two strains showed an affiliation with the genus Gracilibacillus, with Gracilibacillus kekensis CGMCC 1.10681(T) (similarity of 97.4, 98.0 %, respectively) and Gracilibacillus ureilyticus CGMCC 1.7727(T) (similarity of 97.1, 97.8 %, respectively) as their closest relatives. The DNA-DNA hybridization values between strain HB09003(T) and the two type strains were 42.2 and 54.1 %, respectively. On the basis of phenotypic and genotypic data, strain HB09003(T) and HB12160 are proposed to represent a novel species of the genus Gracilibacillus, for which the name Gracilibacillus marinus sp. nov. is proposed. The type strain is HB09003(T) (=CGMCC 1.10343(T) = DSM 23372(T)). PMID:23942614

Huang, Hui-Qin; Wang, Ying; Yuan, Wei-Dao; Xiao, Chuan; Ye, Jian-Jun; Liu, Min; Zhu, Jun; Sun, Qian-Guang; Bao, Shi-Xiang

2013-08-14

257

Classification of Streptomyces phylogroup pratensis (Doroghazi and Buckley, 2010) based on genetic and phenotypic evidence, and proposal of Streptomyces pratensis sp. nov.  

PubMed

The Streptomyces phylogroup pratensis (Doroghazi and Buckley, 2010) contains isolates obtained from grassy fields, as well as Streptomyces flavogriseus ATCC 33331 and strain CGMCC 4.1868. This latter strain was received as Streptomyces griseoplanus but was subsequently found to be mislabeled, and S. flavogriseus ATCC 33331 (=IAF-45-CD) was shown to be clearly distinct from the type strain S. flavogriseus ATCC 25452(T) (=CGMCC 4.1884(T)). In order to evaluate the taxonomic position of phylogroup pratensis further, sequences of the 16S rRNA gene and five protein-coding housekeeping genes (atpD, gyrB, recA, rpoB and trpB) were determined for six strains of the phylogroup and type strains of 19 related species, which were selected by a BLAST search based on the sequences of the phylogroup. The 16S rRNA gene sequences for the phylogroup were identical to those of eight species belonging to cluster I of the S. griseus clade. However, in all the individual protein-coding gene and MLSA phylogenies, the phylogroup strains without exception formed an obviously distinct cluster that could be equated with a new species status. The phylogenetic evidence for the new species assignment was also supported by corresponding DNA-DNA hybridization values and by phenotypic characteristics. It is therefore proposed that the phylogroup should be classified as Streptomyces pratensis sp. nov., and the type strain is ch24(T) (=CGMCC 4.6829(T)=NRRL B-24916(T)). PMID:23769815

Rong, Xiaoying; Doroghazi, James R; Cheng, Kun; Zhang, Limin; Buckley, Daniel H; Huang, Ying

2013-06-14

258

Codon optimization of Bacillus licheniformis ?-1,3-1,4-glucanase gene and its expression in Pichia pastoris  

Microsoft Academic Search

?-1,3-1,4-glucanase (EC3.2.1.73) as an important industrial enzyme has been widely used in the brewing and animal feed additive\\u000a industry. To improve expression efficiency of recombinant ?-1,3-1,4-glucanase from Bacillus licheniformis EGW039(CGMCC 0635) in methylotrophic yeast Pichia pastoris GS115, the DNA sequence encoding ?-1,3-1,4-glucanase was designed and synthesized based on the codon bias of P. pastoris, the codons encoding 96 amino acids

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

2007-01-01

259

Thalassospira xiamenensis sp. nov. and Thalassospira profundimaris sp. nov.  

PubMed

Two bacterial strains, M-5T and WP0211T, were isolated from the surface water of a waste-oil pool in a coastal dock and from a deep-sea sediment sample from the West Pacific Ocean, respectively. Analysis of 16S rRNA gene sequences indicated that both strains belonged to the class Alphaproteobacteria and were closely related to Thalassospira lucentensis (96.1 and 96.2 %, gene sequence similarity, respectively). Based on the results of physiological and biochemical tests, as well as DNA-DNA hybridization experiments, it is suggested that these isolates represent two novel species of the genus Thalassospira. Various traits allow both novel strains to be differentiated from Thalassospira lucentensis, including oxygen requirement, nitrate reduction and denitrification abilities and major fatty acid profiles, as well as their ability to utilize six different carbon sources. Furthermore, the novel strains may be readily distinguished from each other by differences in their motility, flagellation, growth at 4 degrees C and 40 degrees C, their ability to hydrolyse Tween 40 and Tween 80, their utilization of 19 different carbon sources and by quantitative differences in their fatty acid contents. It is proposed that the isolates represent two novel species for which the names Thalassospira xiamenensis sp. nov. (type strain, M-5T=DSM 17429T=CGMCC 1.3998T) and Thalassospira profundimaris sp. nov. (type strain, WP0211T=DSM 17430T=CGMCC 1.3997T) are proposed. PMID:17267971

Liu, Chenli; Wu, Yehui; Li, Li; Ma, Yingfei; Shao, Zongze

2007-02-01

260

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 96.6–98?% 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).

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

2013-01-01

261

Mutation-Screening of Pleurotus Ferulae with High Temperature Tolerance by Nitrogen Ion Implantation  

NASA Astrophysics Data System (ADS)

In order to obtain Pleurotus ferulae with high temperature tolerance, conidiophores of wild type strain ACK were implanted with nitrogen ions in energy of 5 ~15 keV and dose of 1.5 × 1015 ~ 1.5 × 1016 cm-2, and a mutant CGMCC1763 was isolated subsequently through thermotolerant screening method. It was found that during riper period the surface layer mycelium of the mutant in mushroom bag wasn't aging neither grew tegument even above 30° C. The mycelium endurable temperature of the mutant was increased by 5°C compared to that of the wild type strain. The fruiting bodies growth temperature of the mutant was 18 ~22°C in daytime and 8~14°C at night. The highest growth temperature of fruiting bodies of the mutant was increased about 7°C w.r.t. that of original strain. Through three generations investigations, it was found that the mutant CGMCC1763 was stable with high temperature tolerance.

Chen, Henglei; Wan, Honggui; Zhang, Jun; Zeng, Xianxian

2008-08-01

262

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

Members of the haloarchaeal genera Halosarcina and Halogeometricum (family Halobacteriaceae) are closely related to each other and show 96.6-98?% 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 RO1-4(T), Halosarcina pallida BZ256(T) and Halosarcina limi RO1-6(T) are related more to each other than to Halogeometricum borinquense CGMCC 1.6168(T). 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, BZ256(T)?=?KCTC 4017(T)?=?JCM 14848(T)) and Halogeometricum limi comb. nov. (type strain, RO1-6(T)?=?CGMCC 1.8711(T)?=?JCM 16054(T)). PMID:24097833

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

2013-10-01

263

Thermotolerant Kluyveromyces marxianus and Saccharomyces cerevisiae strains representing potentials for bioethanol production from Jerusalem artichoke by consolidated bioprocessing.  

PubMed

Thermotolerant inulin-utilizing yeast strains are desirable for ethanol production from Jerusalem artichoke tubers by consolidated bioprocessing (CBP). To obtain such strains, 21 naturally occurring yeast strains isolated by using an enrichment method and 65 previously isolated Saccharomyces cerevisiae strains were investigated in inulin utilization, extracellular inulinase activity, and ethanol fermentation from inulin and Jerusalem artichoke tuber flour at 40 °C. The strains Kluyveromyces marxianus PT-1 (CGMCC AS2.4515) and S. cerevisiae JZ1C (CGMCC AS2.3878) presented the highest extracellular inulinase activity and ethanol yield in this study. The highest ethanol concentration in Jerusalem artichoke tuber flour fermentation (200 g?L(-1)) at 40 °C achieved by K. marxianus PT-1 and S. cerevisiae JZ1C was 73.6 and 65.2 g?L(-1), which corresponded to the theoretical ethanol yield of 90.0 and 79.7 %, respectively. In the range of 30 to 40 °C, temperature did not have a significant effect on ethanol production for both strains. This study displayed the distinctive superiority of K. marxianus PT-1 and S. cerevisiae JZ1C in the thermotolerance and utilization of inulin-type oligosaccharides reserved in Jerusalem artichoke tubers. It is proposed that both K. marxianus and S. cerevisiae have considerable potential in ethanol production from Jerusalem artichoke tubers by a high temperature CBP. PMID:22760784

Hu, Nan; Yuan, Bo; Sun, Juan; Wang, Shi-An; Li, Fu-Li

2012-07-04

264

Streptomyces chlorus sp. nov. and Streptomyces viridis sp. nov., isolated from soil.  

PubMed

Two actinomycete strains, BK125(T) and BK199(T), isolated from a hay meadow soil sample were investigated to determine their taxonomic position using a polyphasic approach. The isolates produced greenish-yellow and light green aerial mycelium on oatmeal agar, respectively. They contained anteiso-C15?:?0, iso-C15?:?0 and C16?:?0 as the major fatty acids, and MK-9 (H6) and MK-9 (H8) as the predominant isoprenoid quinones. Phylogenetic analysis of the 16S rRNA gene sequences showed that the isolates formed distinct phyletic lines towards the periphery of the Streptomyces prasinus subclade. Analysis of DNA-DNA relatedness between the two isolates showed that they belonged to different genomic species. The organisms were also distinguished from one another and from type strains of species classified in the S. prasinus subclade using a combination of genotypic and phenotypic properties. On the basis of these data, it is proposed that the isolates be assigned to the genus Streptomyces as Streptomyces chlorus sp. nov. and Streptomyces viridis sp. nov. with isolates BK125(T) (?=?KACC 20902(T)?=?CGMCC 4.5798(T)) and BK199(T) (?=?KACC 21003(T)?=?CGMCC 4.6824(T)) as the respective type strains. PMID:22922536

Kim, Byung-Yong; Rong, Xiaoying; Zucchi, Tiago D; Huang, Ying; Goodfellow, Michael

2012-08-24

265

In vitro activities of ICI 194008 and ICI 193428, two new cephem antimicrobial agents.  

PubMed Central

The in vitro activities of two new cephem antibiotics, ICI 193428 and ICI 194008, were compared with those of cefpirome, cefotaxime, ceftazidime, and piperacillin. Essentially all strains of the family Enterobacteriaceae were inhibited by both study drugs at concentrations of less than or equal to 4 micrograms/ml. Both new cephems were comparable to ceftazidime against Pseudomonas aeruginosa (MIC for 90% of strains, 8 micrograms/ml) and were the most active agents tested against Pseudomonas maltophilia (MIC for 90% of strains, 16 micrograms/ml).

Allan, J D; Eliopoulos, G M; Reiszner, E; Moellering, R C

1987-01-01

266

Exploring characteristics of bioelectricity generation and dye decolorization of mixed and pure bacterial cultures from wine-bearing wastewater treatment  

Microsoft Academic Search

This study uncovered microbial characteristics of bioelectricity generation and dye decolorization in single-chamber microbial\\u000a fuel cells (MFCs) using activated sludge for wine-containing wastewater treatment. Phylogenetic tree analysis on 16S rRNA\\u000a gene fragments indicated that the predominant strains on anodic biofilm in acclimatized MFCs were Gamma-Proteobacteria Aeromonas punctata NIU-P9, Pseudomonas plecoglossicida NIU-Y3, Pseudomonas koreensis NIU-X8, Acinetobacter junii NIU-Y8, Stenotrophomonas maltophila NIU-X2.

Jing-Long Han; Ying Liu; Chang-Tang Chang; Bor-Yann Chen; Wen-Ming Chen; Hui-Zhong Xu

2011-01-01

267

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.

2012-01-01

268

Gene cloning, expression, and characterization of a novel trehalose synthase from Arthrobacter aurescens.  

PubMed

Trehalose synthase (TreS) is an intramolecular transglycosylase. It specially catalyzes the conversion of maltose and trehalose. In this study, a novel treS gene, which had a length of 1,797 bp and encoded 598 amino acids, was cloned from Arthrobacter aurescens CGMCC 1.1892 and expressed in Escherichia coli. Thin layer chromatography results indicated that it could catalyze the conversion between maltose and trehalose in one step. However, the ion chromatography results showed that, as a byproduct, about 13% glucose was also produced. The purified recombinant enzyme had a molecular weight of 68 kDa and showed its optimal activity at 35 degrees C and pH 6.5. This enzyme was not thermostable, and its activity was increased by 1 mM Mg2+, Mn2+, and Ca2+ while strongly inhibited by 5 mM Cu2+ and SDS. PMID:19172263

Xiuli, Wu; Hongbiao, Ding; Ming, Yue; Yu, Qiao

2009-01-27

269

Identification of fengycin homologues from Bacillus subtilis with ESI-MS/CID.  

PubMed

Bacillus subtilis fmbJ (CGMCC no.0943) was used to produce lipopeptides antibiotics fengycin. The fengycin mixture was precipitated with 6N HCl and extracted by methanol. Electrospray ionization mass spectrometry/collision-induced dissociation (ESI-MS/CID) were used to analyze the fengycin mixture. In the ESI-MS/CID spectra of fengycin molecular ions, production ions (m/z 1080, m/z 966, m/z 1108 and m/z 994) were always detected. Therefore, these production ions (m/z 1080, m/z 966, m/z 1108 and m/z 994) could be used as fingerprints to quickly detect fengycin A and fengycin B. By the method of ESI-MS/CID, six homologues of fengycin A with C14 to 19 and four homologues of fengycin B with C14 to 17 were characterized. The method will be useful for rapidly determining whether a strain produces fengycin homologues. PMID:19781583

Bie, Xiaomei; Lu, Zhaoxin; Lu, Fengxia

2009-09-23

270

Sanguibacter marinus sp. nov., isolated from coastal sediment.  

PubMed

A Gram-positive, coryneform bacterium, strain 1-19(T), was isolated from coastal sediment from the Eastern China Sea. Phylogenetic analysis based on 16S rRNA gene sequences showed that the organism formed a robust clade with the type species of the genus Sanguibacter and displayed less than 97% gene sequence similarity. Phenotypic characteristics supported the assignment of this organism to the genus Sanguibacter. A range of biochemical features distinguished it from all other Sanguibacter species with validly published names. On the basis of a polyphasic taxonomical analysis, it is proposed that this bacterium is a novel species of Sanguibacter, for which the name Sanguibacter marinus sp. nov. is proposed. The type strain is 1-19(T) (=CGMCC 1.3457(T)=JCM 12547(T)). PMID:16166662

Huang, Ying; Dai, Xin; He, Liang; Wang, Ya-Nan; Wang, Bao-Jun; Liu, Zhiheng; Liu, Shuang-Jiang

2005-09-01

271

Devosia psychrophila sp. nov. and Devosia glacialis sp. nov., from alpine glacier cryoconite, and an emended description of the genus Devosia.  

PubMed

Two psychrophilic strains, Cr7-05(T) and Cr4-44(T), isolated from alpine glacier cryoconite, were characterized by using a polyphasic approach. Both strains were psychrophilic, showing good growth over a temperature range of 1-20 °C. The chemotaxonomic characteristics of these isolates included the presence of C(18:1)?7c and summed feature 3 (C(16:1)?7c and/or C(16:1)?6c) as the major cellular fatty acids, Q-10 as the predominant ubiquinone and diphosphatidylglycerol, phosphatidylglycerol and unknown glycolipids as major polar lipids. The DNA G+C contents of strains Cr7-05(T) and Cr4-44(T) were 61.4 and 63.6 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two isolates belong to the genus Devosia. The 16S rRNA gene sequence similarity between the two strains was 98.6%, but DNA-DNA hybridization indicated 54% relatedness. Strains Cr7-05(T) and Cr4-44(T) exhibited 16S rRNA gene sequence similarity of 94.7-97.2 and 94.9-96.9%, respectively, to the type strains of recognized Devosia species. On the basis of phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data, strains Cr7-05(T) and Cr4-44(T) represent two novel species within the genus Devosia, for which the names Devosia psychrophila sp. nov. (type strain Cr7-05(T) =DSM 22950(T) =CGMCC 1.10210(T) =CIP 110130(T)) and Devosia glacialis sp. nov. (type strain Cr4-44(T) =CGMCC 1.10691(T) =LMG 26051(T)) are proposed. An emended description of the genus Devosia is also provided. PMID:21551324

Zhang, De-Chao; Redzic, Mersiha; Liu, Hong-Can; Zhou, Yu-Guang; Schinner, Franz; Margesin, Rosa

2011-05-06

272

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

2010-05-21

273

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 20-50°C (optimum 37°C) in 1.4-5.1 M NaCl (optimum 3.1-4.3 M) 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 66.4 mol%, 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

2011-09-08

274

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.

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

2011-01-01

275

Bacterial diversity, organic pollutants and their metabolites in two aeration lagoons of common effluent treatment plant (CETP) during the degradation and detoxification of tannery wastewater.  

PubMed

In this study, PCR-RFLP and GC-MS approaches were used to characterize the bacterial diversity, organic pollutants and metabolites during the tannery wastewater treatment process at common effluent treatment plant (CETP). Results revealed that the bacterial communities growing in aeration lagoon-I were dominated with Escherichia sp., Stenotrophomonas sp., Bacillus sp. and Cronobacter sp. while that of aeration lagoon-II prevailed with Stenotrophomonas sp., and Burkholderiales bacterium, respectively. The HPLC and GC-MS analysis revealed that most of the organic pollutants detected in untreated tannery wastewater samples were diminished from bacterial treated tannery wastewater samples. Only two pollutants i.e. L-(+)-lactic acid and acetic acid could not be degraded by bacteria whereas benzene and 2-hydroxy-3-methyl-butanoic acid was produced as new metabolites during the bacterial treatment of tannery wastewater in aeration lagoon II of CETP. Further, it was observed that after bacterial treatment, the toxicity of tannery effluent was reduced significantly allowing 90% seed germination. PMID:21075615

Chandra, Ram; Bharagava, Ram Naresh; Kapley, Atya; Purohit, Hemant J

2010-10-23

276

Degradation of paracetamol by pure bacterial cultures and their microbial consortium.  

PubMed

Three bacterial strains utilizing paracetamol as the sole carbon, nitrogen, and energy source were isolated from a paracetamol-degrading aerobic aggregate, and assigned to species of the genera Stenotrophomonas and Pseudomonas. The Stenotrophomonas species have not included any known paracetamol degraders until now. In batch cultures, the organisms f1, f2, and fg-2 could perform complete degradation of paracetamol at concentrations of 400, 2,500, and 2,000 mg/L or below, respectively. A combination of three microbial strains resulted in significantly improved degradation and mineralization of paracetamol. The co-culture was able to use paracetamol up to concentrations of 4,000 mg/L, and mineralized 87.1 % of the added paracetamol at the initial of 2,000 mg/L. Two key metabolites of the biodegradation pathway of paracetamol, 4-aminophenol, and hydroquinone were detected. Paracetamol was degraded predominantly via 4-aminophenol to hydroquinone with subsequent ring fission, suggesting new pathways for paracetamol-degrading bacteria. The degradation of paracetamol could thus be performed by the single isolates, but is stimulated by a synergistic interaction of the three-member consortium, suggesting a possible complementary interaction among the various isolates. The exact roles of each of the strains in the consortium need to be further elucidated. PMID:22644530

Zhang, Lili; Hu, Jun; Zhu, Runye; Zhou, Qingwei; Chen, Jianmeng

2012-05-31

277

Substrate utilization of stress tolerant methylotrophs isolated from revegetated heavy metal polluted coalmine spoil.  

PubMed

We analyzed methylotrophs in Bina natural vegetation (BNV), and revegetated overburden dump of four (ROBD4) and 12 years (ROBD12), at Bina coal mine in Sonbhadra district. The cultured strains identified as Pseudomonas, Acinetobacter, Stenotrophomonas and Cellvibrio (?-Proteobacteria), Methylophilus, Ralstonia, Burkholderia (?-Proteobacteria) Methylobacterium and Inquilinus (?-Proteobacteria), Bacillus (Firmicutes) and Flexibacter (Sphingobacteria) in their 16s rRNA gene sequence similarity. The strains differed in citrate, lactose, formate, urea and xylose utilization. Methanol utilization by Stenotrophomonas, Inquilinus, Cellvibrio and Flexibacter is for first time. The preferred N- sources were proline, glutamate and nitrate for most of the strains. All strains tolerated (2.5 % NaCl) and SDS (0.2 %); 16 strains survived in crystal violet (0.01 %) and nine strains in sodium azide (0.02 %. Methylotrophic population trend was BNV > ROBD12 > ROBD4. The presence of majority of strain of BNV at ROBD12 and ROBD4 indicated restoration of soil methylotrophic functional diversity in revegetated dumps. PMID:23184579

Giri, D D; Shukla, P N; Ritu, Singh; Kumar, Ajay; Pandey, K D

2012-11-27

278

Anti-bacterial antibodies in Epstein-Barr virus (EBV)-transformed oligoclonal B-cell lines established from normal persons and autoimmune disease patients.  

PubMed

We have established 950 and 430 oligoclonal B-lymphoblastoid cell lines (LCL) from two normal persons and eight autoimmune disease patients, respectively by using Epstein-Barr virus (EBV)-induced transformation. To re-evaluate the EBV technique for production of human monoclonal antibodies (mAb) related to infectious disease, we screened these oligoclonal LCLs for antibodies against 31 bacterial strains systematically. A total of 74 cultures out of 1380 were reactive to a total of 18 strains out of 31. Among these, eight cultures showed 10(-3) antibody (Ab) titers to Pseudomonas aeruginosa serotypes C, E, F and I, Staphylococcus aureus, Serratia marcescens and Bacillus cereus. Ten cultures showed 10(-2) Ab titers to Ps. aeruginosa serotypes D, E, F and I, Ps. maltophilia, Staph. epidermidis, Klebsiella ozaenae, Ser. marcescens and B. subtilis. The results reveal the further possibilities for the EBV technique to produce various infectious disease-related human mAbs. PMID:7765395

Nagatsuka, Y; Hanazawa, S; Koroiwa, Y; Fukuda, T; Suganuma, T; Ono, Y

1994-10-01

279

Monoclonal antibodies to Pseudomonas aeruginosa ferripyochelin-binding protein.  

PubMed Central

Hybridomas secreting specific monoclonal antibodies against the Pseudomonas aeruginosa ferripyochelin-binding protein (FBP) were isolated. These monoclonal antibodies reacted with FBP in immunoblots of outer membrane preparations from all serotypes of P. aeruginosa. Two of the monoclonal antibodies also reacted with FBP in strains of P. putida, P. fluorescens, and P. stutzeri. These antibodies did not react with outer membranes of P. cepacia, "P. multivorans," P. maltophilia, or other gram-negative organisms. The monoclonal antibodies were opsonophagocytic and blocked the binding of [59Fe]ferripyochelin to isolated outer membranes of strain PAO. By indirect immunofluorescence techniques, the monoclonal antibodies were used to demonstrate that FBP is present on the cell surface of P. aeruginosa cells grown in low-iron but not high-iron medium. These observations were confirmed by using 125I in surface-labeling techniques. Images

Sokol, P A; Woods, D E

1986-01-01

280

Motion of the Zinc Ions in Catalysis by a di-Zinc Metallo-beta-Lactamase  

SciTech Connect

We report rapid-freeze-quench X-ray absorption spectroscopy of a dizinc metallo-beta-lactamase (MbetaL) reaction intermediate. The Zn(II) ions in the dinuclear active site of the S. maltophilia Class B3 MbetaL move away from each other, by approximately 0.3 A after 10 ms of reaction with nitrocefin, from 3.4 to 3.7 A. Together with our previous characterization of the resting enzyme and its nitrocefin product complex, where the Zn(II) ion separation relaxes to 3.6 A, these data indicate a scissoring motion of the active site that accompanies the ring-opening step. The average Zn(II) coordination number of 4.5 in the resting enzyme appears to be maintained throughout the reaction with nitrocefin. This is the first direct structural information available on early stage dizinc metallo-beta-lactamase catalysis.

R Breece; Z Hu; M Crowder; D Tierney

2011-12-31

281

Bu-2470, a new peptide antibiotic complex. I. Production, isolation and properties of Bu-2470 A, B1 and B2.  

PubMed

A strain of Bacillus circulans produced a complex of basic peptide antibiotics designated Bu-2470, which was found to contain four active components, A, B1, B2a and B2b. Bu-2470 A specifically inhibited various Pseudomonas species including P. aeruginosa, P. maltophilia and P. putida, but otherwise its antibacterial spectrum was limited to certain Gram-negative organisms. Bu-2470 B1 and B2 (B2a + B2b) showed broad antibiotic activity against Gram-positive and Gram-negative bacteria including Pseudomonas species. The physicochemical and biological properties of Bu-2470 B1 and B2 are very similar to those of the octapeptin group of antibiotics. PMID:6874583

Konishi, M; Sugawara, K; Tomita, K; Matsumoto, K; Miyaki, T; Fujisawa, K; Tsukiura, H; Kawaguchi, H

1983-06-01

282

Medical and surgical management of severe inflammation of the nictitating membrane in a Giant Panda (Ailuropoda melanoleuca).  

PubMed

A 10-year-old male giant panda (Ailuropoda melanoleuca) presented for severe, acute swelling and protrusion of the right nictitating membrane, unresponsive to topical therapy. Excisional biopsy of the nictitating membrane and its associated lacrimal gland was elected due to necrosis and friability of the tissue. Histopathology revealed suppurative, necrotizing conjunctivitis and dacryoadenitis. Culture grew Stenotrophomonas maltophila and Enterococcus spp with extensive antibiotic resistance. Treatment with topical and systemic antibiotics based on sensitivity results was initiated. All treatments were well tolerated. Healing was uncomplicated with no recurrence of the lesion and no clinical evidence of keratoconjunctivitis sicca. Ophthalmic exams and Schirmer tear tests performed opportunistically during postoperative anesthetic procedures were unremarkable, confirming that excision of the nictitating membrane had not caused clinically significant detrimental effects. The etiology of this lesion remains undetermined, but trauma is suspected. To the authors' knowledge, this is the first report of nictitating membrane pathology and excision in the giant panda. PMID:20840099

Boedeker, Nancy C; Walsh, Timothy; Murray, Suzan; Bromberg, Nancy

2010-09-01

283

Community structure analysis of reverse osmosis membrane biofilms and the significance of Rhizobiales bacteria in biofouling.  

PubMed

The biofilm community structure of a biofouled reverse osmosis (RO) membrane was examined using a polyphasic approach, and the dominant phylotypes retrieved were related to the order Rhizobiales, a group of bacteria that is hitherto not implicated in membrane biofouling. A comparison with two other membrane biofilms using T-RFLP fingerprinting also revealed the dominance of Rhizobiales organisms. When pure culture RO biofilm isolates were cultivated aerobically in BIOLOG microplates, most Rhizobiales were metabolically versatile in their choice of carbon substrates. Nitrate reduction was observed in five RO isolates related to Castellaniella, Ochrobactrum, Stenotrophomonas, and Xanthobacter. Many of the key Rhizobiales genera including Bosea, Ochrobactrum, Shinella, and Rhodopseudomonas were detected by PCR to contain the nirK gene responsible for nitrite reductase activity. These findings suggest that Rhizobiales organisms are ecologically significant in membrane biofilm communities under both aerobic and anoxic conditions and may be responsible for biofouling in membrane separation systems. PMID:17695921

Pang, Chee Meng; Liu, Wen-Tso

2007-07-01

284

Biodiversity characterization of cellulolytic bacteria present on native Chaco soil by comparison of ribosomal RNA genes.  

PubMed

Sequence analysis of the 16S ribosomal RNA gene was used to study bacterial diversity of a pristine forest soil and of two cultures of the same soil enriched with cellulolytic bacteria. Our analysis revealed high bacterial diversity in the native soil sample, evidencing at least 10 phyla, in which Actinobacteria, Proteobacteria and Acidobacteria accounted for more than 76% of all sequences. In both enriched samples, members of Proteobacteria were the most frequently represented. The majority of bacterial genera in both enriched samples were identified as Brevundimonas and Caulobacter, but members of Devosia, Sphingomonas, Variovorax, Acidovorax, Pseudomonas, Xanthomonas, Stenotrophomonas, Achromobacter and Delftia were also found. In addition, it was possible to identify cellulolytic taxa such as Acidothermus, Micromonospora, Streptomyces, Paenibacillus and Pseudomonas, which indicates that this ecosystem could be an attractive source for study of novel enzymes for cellulose degradation. PMID:22202170

Talia, Paola; Sede, Silvana M; Campos, Eleonora; Rorig, Marcela; Principi, Dario; Tosto, Daniela; Hopp, H Esteban; Grasso, Daniel; Cataldi, Angel

2011-12-13

285

Carbon utilization profiles of bacteria colonizing the headbox water of two paper machines in a Canadian mill.  

PubMed

Forty-one bacterial strains isolated from the headbox water of two machines in a Canadian paper mill were associated with the genera Asticcacaulis, Acidovorax, Bacillus, Exiguobacterium, Hydrogenophaga, Pseudomonas, Pseudoxanthomonas, Staphylococcus, Stenotrophomonas based on the sequence of their 16S rRNA genes. The metabolic profile of these strains were determined using Biolog EcoPlate, and the bacteria were divided into four metabolic groups. Metabolic profiles of the bacterial communities colonizing the headbox water of two paper machines was also determined weekly over a 1 year period. The only compound that was not reduced by the bacterial community was 2-hydroxybenzoic acid. Utilization frequency of the other carbon sources in the Biolog EcoPlate ranged from 3 to 100%. The metabolic profiles of the bacterial community did not vary considerably between the two paper machines. However, the metabolic profile varied among the sampling dates. PMID:19137341

Kashama, Johnny; Prince, Véronique; Simao-Beaunoir, Anne-Marie; Beaulieu, Carole

2009-01-10

286

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

287

Characterization of Co(III) EDTA-Reducing Bacteria in Metal- and Radionuclide-Contaminated Groundwater  

SciTech Connect

The Waste Area Grouping 5 (WAG5) site at Oak Ridge National Laboratory has a potential to be a field site for evaluating the effectiveness of various bioremediation approaches and strategies. The site has been well studied in terms of its geological and geochemical properties over the past decade. However, despite the importance of microorganisms in bioremediation processes, the microbiological populations at the WAG5 site and their potential in bioremediation have not been similarly evaluated. In this study, we initiated research to characterize the microbial populations in WAG5 groundwater. Approximately 100 isolates from WAG5 groundwater were isolated and selected based on colony morphology. Fifty-five unique isolates were identified by BOX-PCR and subjected to further characterization. 16S rRNA sequences indicated that these isolates belong to seventeen bacterial genera including Alcaligenes (1 isolate), Aquamonas (1), Aquaspirillum (1), Bacillus (10), Brevundimonas (5), Caulobacter (7), Dechloromonas (2), Janibacter (1), Janthinobacterium (2), Lactobacillus (1), Paenibacillus (4), Pseudomonas (9), Rhodoferax (1), Sphingomonas (1), Stenotrophomonas (6), Variovorax (2), and Zoogloea (1). Metal respiration assays identified several isolates, which phylogenically belong or are close to Caulobacter, Stenotrophomonas, Bacillus, Paenibacillus and Pseudomonas, capable of reducing Co(III)EDTA- to Co(II)EDTA{sup 2-} using the defined M1 medium under anaerobic conditions. In addition, using WAG5 groundwater directly as the inoculants, we found that organisms associated with WAG5 groundwater can reduce both Fe(III) and Co(III) under anaerobic conditions. Further assays were then performed to determine the optimal conditions for Co(III) reduction. These assays indicated that addition of various electron donors including ethanol, lactate, methanol, pyruvate, and acetate resulted in metal reduction. These experiments will provide useful background information for future bioremediation field experiments at the WAG5 site.

Gao, Weimin [Arizona State University; Gentry, Terry J [ORNL; Mehlhorn, Tonia L [ORNL; Carroll, Sue L [ORNL; Jardine, Philip M [ORNL; Zhou, Jizhong [University of Oklahoma, Norman

2010-01-01

288

Salinibacter iranicus sp. nov. and Salinibacter luteus sp. nov., isolated from a salt lake, and emended descriptions of the genus Salinibacter and of Salinibacter ruber.  

PubMed

Two Gram-staining-negative, red- and orange-pigmented, non-motile, rod-shaped, extremely halophilic bacteria, designated strains CB7(T) and DGO(T), were isolated from Aran-Bidgol salt lake, Iran. Growth occurred at NaCl concentrations of between 2 and 5 M NaCl and the isolates grew optimally with 3 M NaCl. The optimum pH and temperature for growth of the two strains were pH 7.5 and 37 °C, and they were able to grow over pH and temperature ranges of pH 6-8 and 25-50 °C. The predominant fatty acids of the two isolates were C(18:1)?7c, iso-C(15:0) and summed feature 3 (C(16:1)?7c and/or iso-C(15:0) 2-OH). The polar lipid pattern of the two isolates consisted of diphosphatidylglycerol, phosphatidylcholine, three unidentified lipids, one unidentified aminolipid and three unidentified glycolipids. The only quinone present was menaquinone 7 (MK-7). The G+C contents of the genomic DNA of strains CB7(T) and DGO(T) were 64.8 and 65.6 mol%, respectively. 16S rRNA gene sequence analysis indicated that strains CB7(T) and DGO(T) were related to Salinibacter ruber in the phylum Bacteroidetes. Levels of 16S rRNA gene sequence similarity between strains CB7(T) and DGO(T) and Salinibacter ruber DSM 13855(T) were 93.2 and 93.6%, respectively. The two novel strains shared 98.9% 16S rRNA gene sequence similarity. DNA-DNA hybridization experiments between strains CB7(T) and DGO(T) and Salinibacter ruber DSM 13855(T) indicated levels of relatedness of 44 and 52%, respectively, while the level of relatedness between the two new isolates was 53%. Chemotaxonomic data supported the placement of strains CB7(T) and DGO(T) in the genus Salinibacter. DNA-DNA hybridization studies and biochemical and physiological characterization allowed strains CB7(T) and DGO(T) to be differentiated from Salinibacter ruber and from each other. They are therefore considered to represent two novel species of the genus Salinibacter, for which the names Salinibacter iranicus sp. nov. (type strain CB7(T)=IBRC-M 10036(T)=CGMCC 1.11003(T)) and Salinibacter luteus sp. nov. (type strain DGO(T)=IBRC-M 10423(T)=CGMCC 1.11002(T)) are proposed. Emended descriptions of the genus Salinibacter and of Salinibacter ruber are also presented. PMID:21856978

Makhdoumi-Kakhki, Ali; Amoozegar, Mohammad Ali; Ventosa, Antonio

2011-08-19

289

Mycetocola zhadangensis sp. nov., isolated from snow.  

PubMed

A Gram-stain-positive, aerobic, short rod-shaped bacterium, strain ZD1-4(T), was isolated from the Zhadang Glacier snow pit. The 16S rRNA gene sequence of the isolate showed highest similarity (98.8?%) to that of Mycetocola manganoxydans MB1-14(T). The major fatty acids of strain ZD1-4(T) were anteiso-C15?:?0, C16?:?0, C18?:?0 and anteiso-C17?:?0. It possessed diphosphatidylglycerol as one of the major polar lipids, and MK-10 and MK-11 as the predominant isoprenoid quinones. The DNA G+C content of strain ZD1-4(T) was 63.8±0.2 mol% (Tm). A number of phenotypic characteristics distinguished this bacterium from the type strains of other species of the genus Mycetocola. Moreover, the novel isolate showed only approximately 50?% DNA-DNA relatedness with M. manganoxydans MB1-14(T). According to these genotypic and phenotypic data, it is evident that strain ZD1-4(T) represents a novel species of the genus Mycetocola, for which the name Mycetocola zhadangensis sp. nov. is proposed. The type strain is ZD1-4(T) (?=?KACC 16570(T)?=?CGMCC 1.12042(T)). PMID:23524357

Shen, Liang; Liu, Yongqin; Yao, Tandong; Kang, Shichang; Wang, Yanan; Jiao, Nianzhi; Liu, Hongcan; Zhou, Yuguang; Xu, Baiqing; Liu, Xiaobo

2013-03-22

290

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

2012-10-12

291

Halopiger salifodinae sp. nov., an extremely halophilic archaeon isolated from a salt mine.  

PubMed

A novel extremely halophilic archaeon KCY07-B2(T) was isolated from a salt mine in Kuche county, Xinjiang province, China. Colonies were cream-pigmented and cells were pleomorphic rod-shaped. Strain KCY07-B2(T) was able to grow at 25-50 °C (optimum 37-45 °C) and pH 6.0-8.0 (optimum 7.0). The strain required at least 1.9 M NaCl for growth. MgCl2 was not required. Cells lysed in distilled water. Polar lipid analysis revealed the presence of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, derived from both C20C20 and C20C25 glycerol diethers, together with five glyolipids. The bis-sulfated glycolipid S2-DGD-1 was present. The DNA G+C content was 62.5 mol%. Analysis of the 16S rRNA gene sequence revealed that strain KCY07-B2(T) was closely related to Halopiger xanaduensis SH-6(T) and Halopiger aswanensis 56(T) (95.8?% and 95.5?% similarity, respectively). On the basis of its phenotypic, chemotaxonomic and genotypic characteristics, strain KCY07-B2(T) is considered to represent a novel species of the genus Halopiger, for which the name Halopiger salifodinae sp. nov. is proposed. The type strain is KCY07-B2(T) (?=?JCM 18547(T)?=?CGMCC 1.12284(T)). PMID:23563233

Zhang, Wei-Yan; Meng, Yuan; Zhu, Xu-Fen; Wu, Min

2013-04-05

292

Nocardioides alpinus sp. nov., a psychrophilic actinomycete isolated from alpine glacier cryoconite.  

PubMed

A gram-positive, non-motile, rod-shaped, psychrophilic actinomycete, designated strain Cr7-14(T), was isolated from alpine glacier cryoconite. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Cr7-14(T) was related to members of the genus Nocardioides and shared highest 16S rRNA gene sequence similarities with the type strains of Nocardioides furvisabuli (98.6?%), Nocardioides ganghwensis (98.2?%), Nocardioides oleivorans (98.1?%) and Nocardioides exalbidus (97.6?%). The predominant cellular fatty acids of strain Cr7-14(T) were C(17?:?1)?8c (39.5?%) and iso-C(16?:?0) (32.4?%). The major menaquinone was MK-8(H(4)). The diagnostic diamino acid in the cell-wall peptidoglycan was ll-2,6-diaminopimelic acid. The predominant cell-wall sugars were galactose and rhamnose. The polar lipid pattern contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylinositol, four unknown glycolipids and two unknown polar lipids. The genomic DNA G+C content was 71.9 mol%. On the basis of phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data, a novel species, Nocardioides alpinus sp. nov., is proposed, with Cr7-14(T) (?=?DSM 23325(T)?=?LMG 26053(T)?=?CGMCC 1.10697(T)) as the type strain. PMID:21460134

Zhang, De-Chao; Schumann, Peter; Redzic, Mersiha; Zhou, Yu-Guang; Liu, Hong-Can; Schinner, Franz; Margesin, Rosa

2011-04-01

293

Arthrobacter cryoconiti sp. nov., a psychrophilic bacterium isolated from alpine glacier cryoconite.  

PubMed

A Gram-stain-positive, aerobic, non-motile, psychrophilic bacterium, designated strain Cr6-08(T), was isolated from alpine glacier cryoconite. Growth of strain Cr6-08(T) occurred at 1-25 °C. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain Cr6-08(T) is most closely related to members of the genus Arthrobacter. Strain Cr6-08(T) possessed chemotaxonomic properties consistent with those of the genus Arthrobacter, such as peptidoglycan type A3? (l-Lys-L-Ala(4)), MK-9(H(2)) as major menaquinone and anteiso- and iso-branched compounds (anteiso-C(15?:?0) and iso-C(15?:?0)) as major cellular fatty acids. The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, one unknown glycolipid and three unknown polar lipids. The genomic DNA G+C content of strain Cr6-08(T) was 57.3 mol%. On the basis of phenotypic and chemotaxonomic characteristics, phylogenetic analysis and DNA-DNA relatedness data, strain Cr6-08(T) is considered to represent a novel species of the genus Arthrobacter, for which the name Arthrobacter cryoconiti sp. nov. is proposed. The type strain is Cr6-08(T) (?=?DSM 23324(T) ?=?LMG 26052(T) ?=?CGMCC 1.10698(T)). PMID:21441372

Margesin, Rosa; Schumann, Peter; Zhang, De-Chao; Redzic, Mersiha; Zhou, Yu-Guang; Liu, Hong-Can; Schinner, Franz

2011-03-25

294

A novel non-hydrolytic protein from Pseudomonas oryzihabitans enhances the enzymatic hydrolysis of cellulose.  

PubMed

Several kinds of protein such as the expansin, expansin-like proteins and LPMOs (lytic polysaccharide monooxygenases) are known to exert enhancement effects on cellulase activity. In this study, a novel cellulase synergistic protein named POEP1 was purified from the culture filtrate of Pseudomonas oryzihabitans CGMCC 6169, and was homogeneous on SDS-PAGE with a molecular weight of 60kDa. Mass spectrometry analysis indicated that it was an unknown protein without sequence similarity to the expansin and expansin-like proteins. Evaluation of the enzymatic hydrolysis of filter paper revealed that POEP1 had no cellulase activity but displayed high synergistic activity of 364% at a cellulase concentration of 0.1FPU/g of filter paper. When a mixture containing 0.6FPU cellulase and 700?g POEP1 per g of cellulose was evaluated, the maximal sugar yield was achieved, which was 2.2-fold greater than that with the cellulase alone. POEP1 was found to have functional similarity to the expansin and expansin-like proteins, which could decrease both the hydrogen-bond intensity and crystallinity, and cause the filter paper disruption. This study provided evidence for the existence of novel bacterial proteins in nature serving the same function as expansin and expansin-like proteins. PMID:23916949

Qin, Yi-Min; Tao, Heng; Liu, You-Yan; Wang, Yan-Dong; Zhang, Jing-Ru; Tang, Ai-Xing

2013-07-31

295

Mesorhizobium qingshengii sp. nov., isolated from effective nodules of Astragalus sinicus.  

PubMed

In a study on the diversity of rhizobia isolated from root nodules of Astragalus sinicus, five strains showed identical 16S rRNA gene sequences. They were related most closely to the type strains of Mesorhizobium loti, Mesorhizobium shangrilense, Mesorhizobium ciceri and Mesorhizobium australicum, with sequence similarities of 99.6-99.8%. A polyphasic approach, including 16S-23S intergenic spacer (IGS) RFLP, comparative sequence analysis of 16S rRNA, atpD, glnII and recA genes, DNA-DNA hybridization and phenotypic tests, clustered the five isolates into a coherent group distinct from all recognized Mesorhizobium species. Except for strain CCBAU 33446, from which no symbiotic gene was detected, the four remaining strains shared identical nifH and nodC gene sequences and nodulated with Astragalus sinicus. In addition, these five strains showed similar but different fingerprints in IGS-RFLP and BOX-repeat-based PCR, indicating that they were not clones of the same strain. They were also distinguished from recognized Mesorhizobium species by several phenotypic features and fatty acid profiles. Based upon all the results, we suggest that the five strains represent a novel species for which the name Mesorhizobium qingshengii sp. nov. is proposed. The type strain is CCBAU 33460(T) (=CGMCC 1.12097(T)=LMG 26793(T)=HAMBI 3277(T)). The DNA G+C content of the type strain is 59.52 mol% (Tm). PMID:23041644

Zheng, Wen Tao; Li, Ying; Wang, Rui; Sui, Xin Hua; Zhang, Xiao Xia; Zhang, Jun Jie; Wang, En Tao; Chen, Wen Xin

2012-10-05

296

Salinicoccus halodurans sp. nov., a moderate halophile from saline soil in China.  

PubMed

A moderately halophilic, Gram-positive coccus, designated strain W24(T), was isolated from saline soil in Qinghai province, China. The isolate was able to grow at salinities of 0-24 % (w/v) NaCl (optimally at 8 %, w/v), at pH 5.5-9.0 (optimally at pH 7.5) and at 8-43 degrees C (optimally at 28 degrees C). The genomic DNA G+C content of strain W24(T) was 45.8 mol%. The predominant isoprenoid quinone was MK-6 and the cell wall contained lysine and glycine as diagnostic diamino acids. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The major cellular fatty acids were iso-C(15 : 0), anteiso-C(15 : 0) and C(16 : 0). Based on 16S rRNA gene sequence analysis, strain W24(T) was found to be a member of the genus Salinicoccus and was related most closely to Salinicoccus hispanicus DSM 5352(T) (96.5 % sequence similarity). Based on data from the current polyphasic study, strain W24(T) is considered to represent a novel species of the genus Salinicoccus, for which the name Salinicoccus halodurans sp. nov. is proposed. The type strain is W24(T) (=CGMCC 1.6501(T)=DSM 19336(T)). PMID:18599690

Wang, Xiaowei; Xue, Yanfen; Yuan, Sanqing; Zhou, Cheng; Ma, Yanhe

2008-07-01

297

Longimycelium tulufanense gen. nov., sp. nov., a filamentous actinomycete of the family Pseudonocardiaceae.  

PubMed

A novel filamentous actinomycete strain, designated TRM 46004(T), was isolated from sediment of Aiding Lake in Tulufan Basin (42° 64' N 89° 26' E), north-west China. The isolate was characterized using a polyphasic approach. The isolate formed abundant aerial mycelium with few branches and vegetative mycelium, occasionally twisted and coiled; spherical sporangia containing one to several spherical spores developed at the ends of short sporangiophores on aerial mycelium. The G+C content of the DNA was 65.2 mol%. The isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and xylose, galactose and ribose as the major whole-cell sugars. The diagnostic phospholipids were phosphatidylethanolamine, phosphatidylcholine and phosphatidylglycerol. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H10). The major fatty acids were iso-C16 : 0 and anteiso-C17 : 0. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain TRM 46004(T) formed a distinct lineage within the family Pseudonocardiaceae and showed 91.7-96.1 % 16S rRNA gene sequence similarity with members of the family Pseudonocardiaceae. On the basis of the evidence from this polyphasic study, a novel genus and species, Longimycelium tulufanense gen. nov., sp. nov., are proposed. The type strain of Longimycelium tulufanense is TRM 46004(T) (= CGMCC 4.5737(T) = NBRC 107726(T)). PMID:23315412

Xia, Zhan-Feng; Guan, Tong-Wei; Ruan, Ji-Sheng; Huang, Ying; Zhang, Li-Li

2013-01-11

298

Glycerol/Glucose Co-Fermentation: One More Proficient Process to Produce Propionic Acid by Propionibacterium acidipropionici  

PubMed Central

Cosubstrates fermentation is such an effective strategy for increasing subject metabolic products that it could be available and studied in propionic acid production, using glycerol and glucose as carbon resources. The effects of glycerol, glucose, and their mixtures on the propionic acid production by Propionibacterium acidipropionici CGMCC1.2225 (ATCC4965) were studied, with the aim of improving the efficiency of propionic acid production. The propionic acid yield from substrate was improved from 0.475 and 0.303 g g?1 with glycerol and glucose alone, respectively, to 0.572 g g?1 with co-fermentation of a glycerol/glucose mixture of 4/1 (mol/mol). The maximal propionic acid and substrate conversion rate were 21.9 g l?1 and 57.2% (w/w), respectively, both significantly higher than for a sole carbon source. Under optimized conditions of fed-batch fermentation, the maximal propionic acid yield and substrate conversion efficiency were 29.2 g l?1 and 54.4% (w/w), respectively. These results showed that glycerol/glucose co-fermentation could serve as an excellent alternative to conventional propionic acid fermentation.

Liu, Yin; Zhang, Yong-Guang; Zhang, Ru-Bing; Zhang, Fan

2010-01-01

299

Improving the productivity of propionic acid with FBB-immobilized cells of an adapted acid-tolerant Propionibacterium acidipropionici.  

PubMed

Propionic acid is an important short-chain fatty acid with many applications, but its large-scale bioproduction was hindered by the low productivity. An adapted acid-tolerant Propionibacterium acidipropionici CGMCC 1.2230 strain was selected to produce propionic acid with a relatively high productivity (0.29 g/(Lh)) in the free-cell fermentation. Further immobilized-cell fermentation in fibrous-bed bioreactor (FBB) supported high-level repeated batch fermentations with a high productivity of 0.96 g/(Lh). The FBB also presents the potential to increase final propionic acid concentration by using glucose feeding strategy. The propionic acid concentration was increased to 51.2g/L in the fed-batch fermentation with the productivity of 0.71 g/(Lh). By adopting the above strategies, sugarcane bagasse hydrolysate could support the production of propionic acid with high productivity in the repeat-batch and fed-batch fermentations. The present work would pave one road to the accomplishment of large-scale bioproduction of propionic acid from renewable resources. PMID:22406066

Zhu, Linqi; Wei, Peilian; Cai, Jin; Zhu, Xiangcheng; Wang, Zimeng; Huang, Lei; Xu, Zhinan

2012-02-02

300

Bradyrhizobium arachidis sp. nov., isolated from effective nodules of Arachis hypogaea grown in China.  

PubMed

Twenty-three bacterial strains isolated from root nodules of Arachis hypogaea and Lablab purpureus grown in five provinces of China were classified as a novel group within the genus Bradyrhizobium by analyses of PCR-based RFLP of the 16S rRNA gene and 16S-23S IGS. To determine their taxonomic position, four representative strains were further characterized. The comparative sequence analyses of 16S rRNA and six housekeeping genes clustered the four strains into a distinctive group closely related to the defined species Bradyrhizobium liaoningense, Bradyrhizobium yuanmingense, Bradyrhizobium huanghuaihaiense, Bradyrhizobium japonicum and Bradyrhizobium daqingense. The DNA-DNA relatedness between the reference strain of the novel group, CCBAU 051107(T), and the corresponding type strains of the five mentioned species varied between 46.05% and 13.64%. The nodC and nifH genes of CCBAU 051107(T) were phylogenetically divergent from those of the reference strains for the related species. The four representative strains could nodulate with A. hypogaea and L. purpureus. In addition, some phenotypic features differentiated the novel group from the related species. Based on all the results, we propose a new species Bradyrhizobium arachidis sp. nov. and designate CCBAU 051107(T) (=CGMCC 1.12100(T)=HAMBI 3281(T)=LMG 26795(T)) as the type strain, which was isolated from a root nodule of A. hypogaea and had a DNA G+C mol% of 60.1 (Tm). PMID:23295123

Wang, Rui; Chang, Yue Li; Zheng, Wen Tao; Zhang, Dan; Zhang, Xiao Xia; Sui, Xin Hua; Wang, En Tao; Hu, Jia Qi; Zhang, Li Ya; Chen, Wen Xin

2013-01-05

301

Caldalkalibacillus thermarum gen. nov., sp. nov., a novel alkalithermophilic bacterium from a hot spring in China.  

PubMed

A thermophilic, alkaliphilic and catalase-positive bacterium, designated strain HA6(T), was isolated from a hot spring in China. The strain was aerobic and chemo-organotrophic and grew optimally at 60 degrees C, pH 8.5 and 1.5 % (w/v) NaCl. The cells were Gram-positive rods, forming single terminal endospores. The predominant cellular fatty acids were iso-C(15 : 0) and iso-C(17 : 0). The cell-wall peptidoglycan contained meso-diaminopimelic acid. The genomic DNA G+C content was 45.2 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain HA6(T) formed a distinct lineage within the family Bacillaceae and was most closely related to Bacillus horti K13(T) and Bacillus smithii DSM 4216(T), with sequence similarities of 91.8 and 93.1 %, respectively. On the basis of its physiological and molecular properties, strain HA6(T) should be placed in a novel genus and species, for which the name Caldalkalibacillus thermarum gen. nov., sp. nov. is proposed. The type strain of Caldalkalibacillus thermarum is strain HA6(T) (=CGMCC 1.4242(T)=JCM 13486(T)). PMID:16738094

Xue, Yanfen; Zhang, Xinqi; Zhou, Cheng; Zhao, Yueju; Cowan, Don A; Heaphy, Shaun; Grant, William D; Jones, Brian E; Ventosa, Antonio; Ma, Yanhe

2006-06-01

302

Lysobacter arseniciresistens sp. nov., an arsenite-resistant bacterium isolated from iron-mined soil.  

PubMed

A Gram-negative, aerobic, motile, rod-shaped, arsenite [As(III)]-resistant bacterium, designated strain ZS79(T), was isolated from subsurface soil of an iron mine in China. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain ZS79(T) clustered closely with strains of five Lysobacter species, with 96.9, 96.1, 96.0, 95.8 and 95.3% sequence similarities to Lysobacter concretionis Ko07(T), L. daejeonensis GH1-9(T), L. defluvii IMMIB APB-9(T), L. spongiicola KMM 329(T) and L. ruishenii CTN-1(T), respectively. The major cellular fatty acids were iso-C(15:0) (28.6%), iso-C(17:1)?9c (19.9%), iso-C(16:0) (13.6%), iso-C(11:0) (12.6%) and iso-C(11:0) 3-OH (12.4%). The genomic DNA G+C content was 70.7 mol% and the major respiratory quinone was Q-8. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and an unknown phospholipid. On the basis of morphological and physiological/biochemical characteristics, phylogenetic position and chemotaxonomic data, this strain is considered to represent a novel species of the genus Lysobacter, for which the name Lysobacter arseniciresistens sp. nov. is proposed; the type strain is ZS79(T) (=CGMCC 1.10752(T)=KCTC 23365(T)). PMID:21890727

Luo, Guosheng; Shi, Zunji; Wang, Gejiao

2011-09-02

303

Roseovarius pacificus sp. nov., isolated from deep-sea sediment.  

PubMed

An aerobic, Gram-negative, ovoid to rod-shaped bacterial isolate, strain 81-2(T), was isolated from deep-sea sediment of the Western Pacific Ocean. Strain 81-2(T) was motile, formed faint pink colonies, and was catalase-positive, weakly positive for oxidase and required NaCl for growth. It did not synthesize bacteriochlorophyll a and its DNA G+C content was 62.3 mol%. The 16S rRNA gene sequence of strain 81-2(T) indicated that it was a member of the Roseobacter clade of the class Alphaproteobacteria, with moderate bootstrap support for inclusion in the genus Roseovarius. Its closest phylogenetic neighbour was the type strain of Roseovarius nubinhibens, which shared 95.8 % 16S rRNA gene sequence similarity; strain 81-2(T) was <95.0 % similar to strains of other related species and genera. Phenotypic, chemotaxonomic and phylogenetic data support assignment of this strain to the genus Roseovarius as a representative of a novel species. The name Roseovarius pacificus sp. nov. is proposed, with strain 81-2(T) (=MCCC 1A00293(T)=CGMCC 1.7083(T)=LMG 24575(T)) as the type strain. PMID:19406803

Wang, Baojiang; Tan, Tianfeng; Shao, Zongze

2009-05-01

304

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

2013-01-04

305

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

2013-04-26

306

Pseudonocardia ammonioxydans sp. nov., isolated from coastal sediment.  

PubMed

Actinomycete strain H9T was isolated from coastal sediment of the Jiao-Dong peninsula (near Tsingdao city) in China, and was identified by means of polyphasic taxonomy. The strain grew autotrophically on modified nitrifying medium and heterotrophically on Luria-Bertani medium, with NaCl ranging from 0 to 8% (w/v) (optimal growth at 3.5%). The 16S rRNA gene sequence similarities of strain H9T to members of the genus Pseudonocardia ranged from 93.0 to 97.5%, indicating that strain H9T was phylogenetically related to members of the genus Pseudonocardia. Strain H9T had type IV cell wall and type PIII phospholipid, and its major menaquinone was MK-8 (H4). DNA-DNA relatedness values between strain H9T and Pseudonocardia kongjuensis, Pseudonocardia autotrophica and Pseudonocardia compacta were 42, 13 and 11%, respectively. These results support the conclusion that H9T represents a novel species within the genus Pseudonocardia, for which the name Pseudonocardia ammonioxydans sp. nov. is proposed, with the type strain H9T (= CGMCC 4.1877T = JCM 12462T). PMID:16514026

Liu, Zhi-Pei; Wu, Jian-Feng; Liu, Zhi-Heng; Liu, Shuang-Jiang

2006-03-01

307

Arenitalea lutea gen. nov., sp. nov., a marine bacterium of the family Flavobacteriaceae isolated from intertidal sand.  

PubMed

A yellow, rod-shaped, Gram-negative, facultatively aerobic, gliding bacterium, designed strain P7-3-5(T), was isolated from intertidal sand of the Yellow Sea, China. Analysis of 16S rRNA gene sequences revealed that strain P7-3-5(T) formed a distinct lineage within the family Flavobacteriaceae, sharing 94.2-96.9 % sequence similarity with type strains of species of the most closely related genera, including Hyunsoonleella, Jejuia, Marinivirga and Algibacter. The strain grew at 4-40 °C and with 0.5-5.0 % (w/v) NaCl. It reduced nitrate to nitrite and hydrolysed gelatin and DNA. The major cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G and anteiso-C15 : 0 and the major respiratory quinone was MK-6. Polar lipids included phosphatidylethanolamine (PE), three unidentified aminolipids (AL1-3) and four unidentified lipids (L1-4). The genomic DNA G+C content of strain P7-3-5(T) was 32.1 mol%. Data from this polyphasic study suggest that strain P7-3-5(T) represents a novel species in a new genus in the family Flavobacteriaceae, for which the name Arenitalea lutea gen. nov., sp. nov. is proposed. The type strain of Arenitalea lutea is P7-3-5(T) ( = CGMCC 1.12213(T) = KACC 16457(T)). PMID:23315415

Zhang, Xi-Ying; Liu, Ang; Liu, Chang; Li, Hai; Li, Guo-Wei; Xu, Zhong; Chen, Xiu-Lan; Zhou, Bai-Cheng; Zhang, Yu-Zhong

2013-01-11

308

Reclassification of [Glaciecola] lipolytica and [Aestuariibacter] litoralis in Aliiglaciecola gen. nov., as Aliiglaciecola lipolytica comb. nov. and Aliiglaciecola litoralis comb. nov., respectively.  

PubMed

Following phylogenetic analysis based on 16S rRNA gene sequences, together with DNA G+C contents and differential chemotaxonomic and physiological characteristics, a new genus with the name Aliiglaciecola gen. nov. is proposed to more appropriately accommodate two recognized species of the genera Glaciecola and Aestuariibacter. Accordingly, [Glaciecola] lipolytica and [Aestuariibacter] litoralis should be reassigned to the novel genus as Aliiglaciecola lipolytica comb. nov. (type strain, E3(T) = JCM 15139(T) = CGMCC 1.7001(T)) and Aliiglaciecola litoralis comb. nov. (type strain, KMM 3894(T) = JCM 15896(T) = NRIC 0754(T)), respectively. Aliiglaciecola lipolytica is proposed as the type species of this new genus. Physiologically, the combined characteristics of positive reactions for nitrate reduction and growth at 4 °C and 36 °C distinguish the new genus from the genera Aestuariibacter and Glaciecola by one to three traits. Moreover, the new genus is also distinguished from the genus Glaciecola by the fatty acid profile and distinguished from the genus Aestuariibacter by the differences of major isoprenoid quinone (MK-7 vs Q-8) and DNA G+C content (40.8-43.0 mol% vs 48.0-54.0 mol%). PMID:23315410

Jean, Wen Dar; Hsu, Cheng Yu; Huang, Ssu-Po; Chen, Jwo-Sheng; Lin, Saulwood; Su, Mong-Huai; Shieh, Wung Yang

2013-01-11

309

Xiangella phaseoli gen. nov., sp. nov., a member of the family Micromonosporaceae.  

PubMed

A novel endophytic actinomycete, designated strain NEAU-J5(T) was isolated from roots of snap bean (Phaseolus vulgaris L.). Comparative analysis of the 16S rRNA gene sequence indicated that NEAU-J5(T) is phylogenetically related to members of the family Micromonosporaceae. The whole-cell sugars were galactose, mannose and glucose. The predominant menaquinones were MK-9(H4) and MK-9(H6). The major fatty acids were C16:0, C18:0, C17:1?7c, iso-C15:0 and C17:0. The phospholipids were phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol and phosphatidylinositol mannoside. The DNA G+C content was 72.2 mol%. On the basis of the morphological and chemotaxonomic characteristics, phylogenetic analysis and characteristic patterns of 16S rRNA gene signature nucleotides, strain NEAU-J5(T) represents a novel species of a new genus within the family Micromonosporaceae, for which the name Xiangella phaseoli gen. nov., sp. nov. is proposed. The type strain of Xiangella phaseoli is strain NEAU-J5(T) (=CGMCC 4.7038(T)=DSM 45730(T)). PMID:23104362

Wang, Xiangjing; Jia, Feiyu; Liu, Chongxi; Zhao, Junwei; Wang, Liang; Shen, Yue; Wang, Jidong; Zhang, Ji; Li, Chuang; Xiang, Wensheng

2012-10-26

310

Evaluation of PASCO MIC-ID system for identifying gram-negative bacilli.  

PubMed Central

A production model of the semi-automated PASCO MIC-ID system (PASCO Laboratories, Wheat Ridge, Colo.) was evaluated with 122 groups or species of gram-negative bacilli, which included typical (499 cultures) and atypical (37 cultures) strains of fermenters and nonfermenters. The PASCO system identified 90.9% of 536 cultures accurately; these included 90.8% of 152 nonfermenters, 93.8% of 308 enteric fermenters, and 78.9% of 76 oxidase-positive fermenters. These results were obtained with the aid of serologic tests and a few additional biochemical tests, when recommended by the PASCO system. Of the 14 misidentified nonfermenters, 3 were Pseudomonas paucimobilis, 3 were Weeksella virosa (Centers for Disease Control group IIf), 2 were Xanthomonas (Pseudomonas) maltophilia, and 6 were randomly distributed among the other groups and species tested. The 19 enteric fermenters that were misidentified were randomly distributed among the groups and species tested. Of the 16 misidentified oxidase-positive fermenters, 4 were Pasteurella ureae, and 12 were randomly distributed among the other groups and species. The system identified the most commonly encountered organisms at a rate of 95% or better. The PASCO system is easy to inoculate and read. A slightly improved data base should remedy most of the identification problems.

Rhoden, D L; Schable, B; Smith, P B

1987-01-01

311

Reliability of early identifications obtained with Enterobacteriaceae-plus biochemical cards in the automicrobic system.  

PubMed

The AutoMicrobic system (AMS) is capable of identifying most Enterobacteriaceae within 8 h and many glucose-nonfermenting, gram-negative bacilli after 13 h of incubation. Early preliminary results can be readily obtained from the computer as the tests incubate. Data with 1,023 bacterial isolates were reviewed to determine the relative accuracy of 4-, 6-, 8-, 10-, and 13-h identifications. All AutoMicrobic system identifications with probability (P) values of less than 0.80 were considered equivocal responses which needed supplementary tests before a final report could be issued. Analysis of our data suggests that early identifications of Morganella morganii, Acinetobacter sp., Yersinia spp., Salmonella spp. (other than Salmonella typhi), Shigella spp. (other than Shigella sonnei), Enterobacter agglomerans, Pseudomonas spp. (other than Pseudomonas aeruginosa or Pseudomonas maltophilia), Klebsiella spp. (other than Klebsiella pneumoniae or Klebsiella oxytoca), Citrobacter amalonauticus, Serratia liquefaciens, or Vibrio spp. Should be considered nonspecific responses, even when P greater than or equal to 0.80. Other identifications reported after 4 h were 96% accurate. At least half of our isolates (60% of our Enterobacteriaceae) could be identified reliably within 4 h, the remaining isolates required longer incubation. PMID:6749890

Barry, A L; Badal, R E

1982-08-01

312

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

313

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

2011-08-24

314

Evaluation of the Minitek system for identification of nonfermentative and nonenteric fermentative Gram-negative bacteria.  

PubMed Central

The Minitek identification system (MT) was compared with a conventional testing battery for the characterization of 735 isolates which included 57 species and groups of nonfermentative (NF) and nonenteric fermentative (NEF) gram-negative bacteria. The MT correctly identified 585 of 616 NF (94,96%) and 115 of 119 NEF (96.65%) bacteria and 700 of 735 strains (95.24%) overall. A total of 31 NF and NEF (4.22%) bacteria were misidentified, and no identification was determined for four strains (0.69%). All strains of Acinetobacter anitratus, Pseudomonas maltophilia, P. fluroescens, and P. putida and all but one strain of P. aeruginosa were correctly identified. The most frequently misidentified taxa were CDC group Va-1, P. pickettii (Va-2), P. mendocina, and Moraxella urethralis (M-4). Supplemental tests were needed for the complete identification of 214 strains (29.11%). An average of 1.54 supplemental tests were used with each of these strains. A total of 134 strains (18.23%) had their identification delayed by 1 day due to supplemental testing. We recommend the use of the 42 degree C growth test with the MT. When used in accord with the manufacturer's instructions and with the MT code book the MT was found to be a valuable system for the identification of a wide variety of common and infrequently encountered NF and NEF bacteria.

Chester, V; Cleary, T J

1980-01-01

315

Inoculation with microorganisms of Lolium perenne L.: evaluation of plant growth parameters and endophytic colonization of roots.  

PubMed

Turfgrasses are not only designed for recreation activities, but they also provide beneficial environmental effects and positively influence the human wellness. Their major problems are predisposition to tearing out and microbial diseases. The aim of this study was to investigate whether the inoculation of microorganisms can be effective to improve plant growth and root development of perennial ryegrass, to evaluate new sustainable practice for green preservation. A microorganism-based commercial product was used to amend hydroponically grown Lolium perenne L. and results compared with the use of the same filtered product, a phytohormone solution and an untreated control. Plants were grown for five weeks, shoots cut and measured at one-week interval and, at the end, roots were measured for length and weight. Shoot resistance to tearing out was also tested. Moreover, the main microbial groups present in the product were characterized and the microbial profile of sand and root samples was investigated by PCR-DGGE. The plants treated with the product showed an increased resistance to tearing out with respect to other treatments and roots were longer with respect to the control. Microbial analyses of the product evidenced bacterial and yeast species with plant growth promoting activity, such as Stenothrophomonas maltophilia, Candida utilis and several Lactobacillus species. Some Lactobacillus strains were also found to be able to colonize plant roots. In conclusion, the treatment with microorganisms has a great potential for the maintenance and increased performance of turfgrass surfaces. PMID:23632388

Gaggìa, Francesca; Baffoni, Loredana; Di Gioia, Diana; Accorsi, Mattia; Bosi, Sara; Marotti, Ilaria; Biavati, Bruno; Dinelli, Giovanni

2013-04-28

316

In vitro evaluation of Ro 09-1227, a novel catechol-substituted cephalosporin.  

PubMed Central

Ro 09-1227 is a novel 7-position catechol-substituted parenteral cephalosporin that also has a 3-position radical similar to previously described cephems. The Ro 09-1227 spectrum was slightly wider than that of ceftazidime against members of the family Enterobacteriaceae tested, principally because of greater activity against species producing Richmond-Sykes type I beta-lactamases. Ro 09-1227 was also more active than ceftazidime against some strains producing extended-spectrum plasmid-encoded beta-lactamases, such as TEM-3, -4, -5, -6, -7, and -9, SHV-2 and -3, and CAZ-2. Most strains of Pseudomonas aeruginosa, Xanthomonas maltophilia, and Acinetobacter spp. were also more susceptible to Ro 09-1227 than cefotaxime, ceftriaxone, cefoperazone, and ceftazidime. Haemophilus influenzae (MIC for 90% of strains tested [MIC90], 0.5 micrograms/ml), Neisseria gonorrhoeae (MIC90, 0.015 micrograms/ml), and Moraxella (Branhamella) catarrhalis (MIC90, 0.5 micrograms/ml) were also Ro 09-1227 susceptible. Ro 09-1227 activity against important gram-positive cocci was most comparable to that of ceftazidime. Bacteroides fragilis (MIC90, greater than 32 micrograms/ml) and the enterococci (MIC90, greater than 32 micrograms/ml) were resistant to Ro 09-1227. These in vitro results indicate that this catechol-substituted cephalosporin may be useful as an empiric agent, especially for some isolates resistant to currently available broad-spectrum cephalosporins.

Jones, R N; Erwin, M E

1992-01-01

317

[Gram negative bacilli endocarditis ].  

PubMed

Gram negative bacilli endocarditis are unfrequent. Nevertheless we encountered 28 cases of them (8.8%) among 320 endocarditis of which 10 were primitive and 7 cases (10.9%) among 65 prosthetic endocarditis. Bacterial species were 12 Pseudomonas aeruginosa, 2 Ps, stutzeri, 1 Ps. maltophilia, 2 Klebsiella pneumoniae, 2 Escherichia coli, 3 Serratia marcescans, 1 Enterobacter cloacae, 1 Brucella, 1 Hemophilus aphrophilus, 1 Fusobacterium funduliformis, 18 cases were hospital acquired infections related to cardiac surgery (4 cases), intracardiac catheterization (5 cases), intravenous catheter (4 cases). Uncontrolled infection or cardiac insufficiency underwent respectively in 14 and 18 cases. The overall mortality was 50 p. cent. The death occurred more frequently in primitive endocarditis (70%) than in secondary native endocarditis (45%) or prosthetic endocarditis (29%). It was also more frequent in Pseudomonas endocarditis (59%) than with other species (36%) and more frequent when cardiac sufficiency was present (50%). 15 patients underwent surgical procedure of which 6 died (40%). The results were better if the infection was cured before surgical procedures: 5 deaths occurred when the culture of the valves remained positive (9 cases) but none when it was negative. The 5 most recent cases of prosthetic endocarditis were cured. Since 1979, no death occurred among treated patients. we concluded that surgery is usually necessary but after an effective antibiotic therapy over a 4 or 6 week period. PMID:6750526

Witchitz, S; Regnier, B; Witchitz, J; Schlemmer, B; Bouvet, E; Vachon, F

1982-06-01

318

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 20-50 °C (optimum 37 °C), at 1.4-4.8 M NaCl (optimum 2.1 M NaCl), at 0.05-1.0 M MgCl2 (optimum 0.3 M MgCl2) and at pH 6.0-9.0 (optimum pH 7.0) while strain YCA11 was able to grow at 20-50 °C (optimum 37 °C), at 2.1-4.8 M NaCl (optimum 3.1 M NaCl), at 0.01-0.7 M MgCl2 (optimum 0.1 M 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 64.5 mol%, 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

2013-08-15

319

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

2010-12-17

320

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

321

Tenacibaculum xiamenense sp. nov., an algicidal bacterium isolated from coastal seawater.  

PubMed

A Gram-stain-negative, elongated rod-shaped, yellow-pigmented, aerobic bacterial strain, designated WJ-1(T), was isolated from coastal seawater in Xiamen, Fujian province, China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain WJ-1(T) fell within the genus Tenacibaculum and was most closely associated with Tenacibaculum aestuarii SMK-4(T) (96.7?% 16S rRNA gene sequence similarity); lower similarities were shown to other members of the genus Tenacibaculum (<96.2?%). The strain formed a distinct lineage with Tenacibaculum litopenaei B-I(T) (96.0?%), Tenacibaculum geojense YCS-6(T) (94.5?%) and Tenacibaculum jejuense CNURIC 013(T) (95.4?%). Growth was observed at temperatures from 16 to 38 °C, at salinities from 2 to 4?% and at pH 6-9. The major fatty acids were summed feature 3 (C16?:?1?6c and/or C16?:?1?7c), iso-C17?:?0 3-OH, iso-C15?:?0 and iso-C15?:?0 3-OH. The DNA G+C content of strain WJ-1(T) was 33.2 mol% and the major respiratory quinone was menaquinone-6 (MK-6). Differential phenotypic properties and phylogenetic distinctiveness in this study distinguished strain WJ-1(T) from all other members of the genus Tenacibaculum. According to the morphology, physiology, fatty acid composition and 16S rRNA gene sequence data, strain WJ-1(T) represents a novel species of the genus Tenacibaculum, for which the name Tenacibaculum xiamenense sp. nov. is proposed. The type strain is WJ-1(T) (?=?CGMCC 1.12378(T)?=?LMG 27422(T)). PMID:23543502

Li, Yi; Wei, Jun; Yang, Caiyun; Lai, Qiliang; Chen, Zhangran; Li, Dong; Zhang, Huajun; Tian, Yun; Zheng, Wei; Zheng, Tianling

2013-03-29

322

Sphingomonas rubra sp. nov., isolated from bioreactor wastewater.  

PubMed

A Gram-reaction-negative, rod-shaped, motile, neutrophilic bacterium, designated strain BH3(T), was isolated from wastewater of a sequential batch reactor treating wastewater taken from a leather plant. The isolate grew in 0-8 % (w/v) NaCl, at pH 6-9 and at 4-45 °C. Chemotaxonomic analysis showed that strain BH3(T) had characteristics typical of members of the genus Sphingomonas, such as the presence of sphingolipids, Q-10 and 2-hydroxymyristic acid and the absence of 3-hydroxy fatty acids. The presence of C(18 : 1)?7c (39.2 %) and C(16 : 0) (11.2 %) as major fatty acids, C(14 : 0) 2-OH (20.6 %) as the major 2-hydroxy fatty acid and homospermidine as the major polyamine indicated that strain BH3(T) belonged to the genus Sphingomonas sensu stricto. The genomic DNA G+C content of strain BH3(T) was 65.6 mol%. 16S rRNA gene sequence similarities between the isolate and closely related members of the genus Sphingomonas sensu stricto ranged from 92.6 to 97.3 %, the highest sequence similarities being to Sphingomonas melonis DSM 14444(T) (97.3 %) and Sphingomonas aquatilis DSM 15581(T) (97.3 %). Based on its phenotypic characteristics and the results of DNA-DNA hybridization studies and 16S rRNA gene sequence comparisons, strain BH3(T) represents a novel species of the genus Sphingomonas sensu stricto, for which the name Sphingomonas rubra sp. nov. is proposed. The type strain is BH3(T) (?=?CGMCC 1.9113(T) ?=?JCM 16230(T)). PMID:20511462

Huo, Ying-Yi; Xu, Xue-Wei; Liu, Sheng-Pan; Cui, Heng-Lin; Li, Xue; Wu, Min

2010-05-28

323

Barrientosiimonas humi gen. nov., sp. nov., an actinobacterium of the family Dermacoccaceae.  

PubMed

Three novel actinobacteria, strains 39(T), 40 and 41, were isolated from soil collected from Barrientos Island in the Antarctic. The taxonomic status of these strains was determined using a polyphasic approach. Comparison of 16S rRNA gene sequences revealed that strain 39(T) represented a novel lineage within the family Dermacoccaceae and was most closely related to members of the genera Demetria (96.9 % 16S rRNA gene sequence similarity), Branchiibius (95.7 %), Dermacoccus (94.4-95.3 %), Calidifontibacter (94.6 %), Luteipulveratus (94.3 %), Yimella (94.2 %) and Kytococcus (93.1 %). Cells were irregular cocci and short rods. The peptidoglycan type was A4? with an L-Lys-L-Ser-D-Asp interpeptide bridge. The cell-wall sugars were galactose and glucose. The major menaquinone was MK-8(H(4)). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphoglycolipid, two glycolipids and one unknown phospholipid. The acyl type of the cell-wall polysaccharide was N-acetyl. The major cellular fatty acids were anteiso-C(17 : 0) (41.97 %), anteiso-C(17 : 1)?9c (32.16 %) and iso-C(16 : 0) (7.68 %). The DNA G+C content of strain 39(T) was 68.4 mol%. On the basis of phylogenetic and phenotypic differences from other genera of the family Dermacoccaceae, a novel genus and species, Barrientosiimonas humi gen. nov., sp. nov., is proposed; the type strain of the type species is 39(T) (=CGMCC 4.6864(T) = DSM 24617(T)). PMID:22389286

Lee, Learn-Han; Cheah, Yoke-Kqueen; Sidik, Shiran Mohd; Xie, Qing-Yi; Tang, Yi-Li; Lin, Hai-Peng; Mutalib, Nurul-Syakima Ab; Hong, Kui

2012-03-02

324

Paenibacillus taihuensis sp. nov., isolated from an eutrophic lake.  

PubMed

Two Gram-stain-negative, facultatively anaerobic and endospore-forming rod-shaped bacterial strains, THMBG22(T) and R24, were isolated from decomposing algal scum. Phylogenetic analysis of 16S rRNA gene sequences showed that the two strains were closely related to each other (99.7?% similarity) and that they were also closely related to Paenibacillus sacheonensis DSM 23054(T) (97-97.1?%) and Paenibacillus phyllosphaerae DSM 17399(T) (96.1-96.4?%). This affiliation was also supported by rpoB-based phylogenetic analyses. Growth was observed at 20-40 °C (optimum, 30-37 °C) and at pH 5.0-9.0 (optimum, pH 6.0-7.0). The cells contained MK-7 as the sole respiratory quinone and anteiso-C15?:?0 as the major cellular fatty acid. Their cellular polar lipids were composed of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and 12 unidentified polar lipids. The diamino acid of their cell-wall peptidoglycan was meso-diaminopimelic acid. The DNA-DNA hybridization value between THMBG22(T) and R24 was 84?%, and DNA-DNA relatedness to the most closely related species with a validly published name (P. sacheonensis) was 35-37?%. These results supported the assignment of the new isolates to the genus Paenibacillus and also distinguished them from the previously described species of the genus Paenibacillus. Hence, it is proposed that strains THMBG22(T) and R24 represent a novel species of the genus Paenibacillus, with the name Paenibacillus taihuensis sp. nov. The type strain is THMBG22(T) (?=?CGMCC 1.10966(T)?=?NBRC 108766(T)). PMID:23625256

Wu, Yu-Fan; Wu, Qing-Long; Liu, Shuang-Jiang

2013-04-26

325

Oligosphaera ethanolica gen. nov., sp. nov., an anaerobic, carbohydrate-fermenting bacterium isolated from methanogenic sludge, and description of Oligosphaeria classis nov. in the phylum Lentisphaerae.  

PubMed

A mesophilic, obligately anaerobic, carbohydrate-fermenting bacterium, designated 8KG-4(T), was isolated from an upflow anaerobic sludge blanket reactor treating high-strength organic wastewater from salted vegetable production processes. Cells of strain 8KG-4(T) were non-motile, spherical and 0.7-1.5 µm in diameter (mean, 1.0 µm). Spore formation was not observed under any culture conditions tested. The strain grew optimally at 37 °C (range for growth 25-40 °C) and pH 7.0 (range, pH 6.5-7.5), and could grow fermentatively on glucose, ribose, xylose, galactose and sucrose. The main end products of glucose fermentation were acetate, ethanol and hydrogen. Organic acids, alcohols and amino acids were not utilized for growth. Yeast extract was not required for growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite and Fe(III) nitrilotriacetate were not used as terminal electron acceptors. The G+C content of the genomic DNA was 61.1 mol%. 16S rRNA gene sequence analysis revealed that the isolate represented a previously uncultured lineage at the subphylum level within the phylum Lentisphaerae known as 'WWE2 subgroup I'. The major cellular fatty acids were anteiso-C(15?:?0), iso-C(16?:?0), C(16?:?0) and anteiso-C(17?:?0). Respiratory quinones were not detected. The most abundant polar lipid of strain 8KG-4(T) was phosphatidylethanolamine. A novel genus and species, Oligosphaera ethanolica gen. nov., sp. nov., is proposed to accommodate strain 8KG-4(T) (?=?JCM 17152(T)?=?DSM 24202(T) ?=?CGMCC 1.5160(T)). In addition, we formally propose Oligosphaeria classis nov. and the subordinate taxa Oligosphaerales order nov. and Oligosphaeraceae fam. nov. PMID:22523166

Qiu, Yan-Ling; Muramatsu, Mizuho; Hanada, Satoshi; Kamagata, Yoichi; Guo, Rong-Bo; Sekiguchi, Yuji

2012-04-20

326

Vibrio xiamenensis sp. nov., a cellulase-producing bacterium isolated from mangrove soil.  

PubMed

A taxonomic study was carried out on a cellulase-producing bacterium, strain G21(T), isolated from mangrove soil in Xiamen, Fujian province, China. Cells were Gram-negative, slightly curved rods, motile with a single polar flagellum. The strain grew at 15-40 °C and in 0.5-10% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain G21(T) belonged to the genus Vibrio and formed a clade with Vibrio furnissii ATCC 350116(T) (97.4% sequence similarity), V. fluvialis LMG 7894(T) (97.1%) and V. ponticus CECT 5869(T) (96.1%). However, multilocus sequence analysis (using rpoA, recA, mreB, gapA, gyrB and pyrH sequences) and DNA-DNA hybridization experiments indicated that the strain was distinct from the closest related Vibrio species. Additionally, strain G21(T) could be differentiated from them phenotypically by the ability to grow in 10% NaCl but not on TCBS plates, its enzyme activity spectrum, citrate utilization, oxidization of various carbon sources, hydrolysis of several substrates and its cellular fatty acid profile. The G+C content of the genomic DNA was 46.0 mol%. The major cellular fatty acids were summed feature 3 (C(16:1)?7c and/or iso-C(15:0) 2-OH), C(16:0) and C(18:1)?7c. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol, with trace amounts of diphosphatidylglycerol. The predominant quinones were Q-8 and Q-7. Based on phylogenetic, phenotypic and chemotaxonomic characteristics and DNA-DNA hybridization analysis, it is concluded that strain G21(T) represents a novel species of the genus Vibrio, for which the name Vibrio xiamenensis sp. nov. is proposed. The type strain is G21(T) (?=?DSM 22851(T) ?=?CGMCC 1.10228(T)). PMID:22039001

Gao, Zhao-Ming; Xiao, Jing; Wang, Xing-Na; Ruan, Ling-Wei; Chen, Xiu-Lan; Zhang, Yu-Zhong

2011-10-28

327

Paenibacillus taohuashanense sp. nov., a nitrogen-fixing species isolated from rhizosphere soil of the root of Caragana kansuensis Pojark.  

PubMed

A nitrogen-fixing bacterium, designated strain gs65(T), was isolated from a rhizosphere soil sample of Caragana kansuensis Pojark. Phylogenetic analysis based on a fragment of the nifH gene and the full-length 16S rRNA gene sequence revealed that strain gs65(T) is a member of the genus Paenibacillus. High levels of 16S rRNA gene similarity were found between strain gs65(T) and Paenibacillus borealis DSM 13188(T) (97.5 %), Paenibacillus odorifer ATCC BAA-93(T) (97.3 %), Paenibacillus durus DSM 1735(T) (97.0 %) and Paenibacillus sophorae DSM23020(T) (96.9 %). Levels of 16S rRNA gene sequence similarity between strain gs65(T) and the type strains of other recognized members of the genus Paenibacillus were below 97.0 %. Levels of DNA-DNA relatedness between strain gs65(T) and P. borealis DSM 13188(T), P. odorifer ATCC BAA-93(T) (97.3 %), P. durus DSM 1735(T) and P. sophorae DSM23020(T) were 35.9, 38.0, 34.2 and 35.5 % respectively. The DNA G+C content of strain gs65(T) was determined to be 51.6 mol%. The major fatty acids were found to be iso-C(14:0), anteiso-C(15:0) and iso-C(16:0). On the basis of its phenotypic characteristics and levels of DNA-DNA hybridization, strain gs65(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus taohuashanense sp. nov. is proposed. The type strain is gs65(T) (=CGMCC 1.12175(T) = DSM 25809(T)). PMID:22791017

Xie, Jian-Bo; Zhang, Li-Hong; Zhou, Yu-Guang; Liu, Hong-Can; Chen, San-Feng

2012-07-12

328

Paenibacillus jilunlii sp. nov., a nitrogen-fixing species isolated from the rhizosphere of Begonia semperflorens.  

PubMed

A nitrogen-fixing bacterium, designated strain Be17(T), was isolated from rhizosphere soil of Begonia semperflorens planted in Beijing Botanical Garden, PR China. Phylogenetic analyses based on a segment of the nifH gene sequence and a full-length 16S rRNA gene sequence revealed that strain Be17(T) was a member of the genus Paenibacillus. High levels of 16S rRNA gene sequence similarity were found between strain Be17(T) and Paenibacillus graminis RSA19(T) (97.9 %), Paenibacillus sonchi LMG 24727(T) (97.8 %), Paenibacillus riograndensis CECT 7330(T) (96.2 %) and Paenibacillus borealis DSM 13188(T) (96.1 %), respectively. Levels of 16S rRNA gene sequence similarity between strain Be17(T) and the type strains of other recognized members of the genus Paenibacillus were below 96.0 %. However, the DNA-DNA hybridization values between strain Be17(T) and P. graminis RSA19(T), P. sonchi LMG 24727(T) and P. riograndensis CECT 7330(T) were 47.9 %, 38.7 % and 37.5 %, respectively. The DNA G+C content of strain Be17(T) was 52.9 mol%. The major fatty acid component of strain Be17(T) was anteiso-branched C(15 : 0) (30.92 %). The major isoprenoid quinone was MK-7. The cell-wall peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. On the basis of its phenotypic characteristics, 16S rRNA gene sequences, DNA G+C content, DNA-DNA relatedness, chemotaxonomic properties and nifH gene sequence, strain Be17(T) represents a nitrogen-fixing strain of a novel species of the genus Paenibacillus, for which the name Paenibacillus jilunlii sp. nov. is proposed. The type strain is Be17(T) (?=?CGMCC 1.10239(T)?=?DSM 23019(T)). PMID:20601486

Jin, Hao-Jie; Zhou, Yu-Guang; Liu, Hong-Can; Chen, San-Feng

2010-07-02

329

Alcanivorax hongdengensis sp. nov., an alkane-degrading bacterium isolated from surface seawater of the straits of Malacca and Singapore, producing a lipopeptide as its biosurfactant.  

PubMed

A taxonomic study was carried out on strain A-11-3(T), which was isolated from an oil-enriched consortia from the surface seawater of Hong-Deng dock in the Straits of Malacca and Singapore. Cells were aerobic, Gram-negative, non-spore-forming irregular rods. The strain was catalase- and oxidase-negative. It grew on a restricted spectrum of organic compounds, including some organic acids and alkanes. 16S rRNA gene sequence comparisons showed that strain A-11-3(T) was most closely related to the type strains of Alcanivorax jadensis (96.8 % sequence similarity), Alcanivorax borkumensis (96.8 %), Alcanivorax dieselolei (94.8 %), Alcanivorax venustensis (94.2 %) and Alcanivorax balearicus (94.0 %). The predominant fatty acids were C(16 : 0) (31.2 %), C(18 : 1)omega7c (24.8 %), C(18 : 0) (9.6 %), C(12 : 0) (8.3 %), C(16 : 1)omega7c (8.3 %) and C(16 : 0) 3-OH (5.1 %). The G+C content of the genomic DNA was 54.7 mol%. Moreover, the strain produced lipopeptides as its surface-active compounds. According to physiological and biochemical tests, DNA-DNA hybridization results and sequence comparisons of the 16S-23S internal transcribed spacer, the gyrB gene and the alkane hydroxylase gene alkB1, strain A-11-3(T) was affiliated with the genus Alcanivorax but could be readily distinguished from recognized Alcanivorax species. Therefore strain A-11-3(T) represents a novel species of the genus Alcanivorax for which the name Alcanivorax hongdengensis sp. nov. is proposed. The type strain is A-11-3(T) (=CGMCC 1.7084(T)=LMG 24624(T)=MCCC 1A01496(T)). PMID:19502338

Wu, Yehui; Lai, Qiliang; Zhou, Zhongwen; Qiao, Nan; Liu, Chenli; Shao, Zongze

2009-06-01

330

Streptomyces aidingensis sp. nov., an actinomycete isolated from lake sediment.  

PubMed

A novel actinomycete strain, designated TRM 46012(T), was isolated from sediment of Aiding Lake in Tulufan Basin (42° 64' N 89° 26' E), north-west China. The strain was aerobic and Gram-staining-positive with an optimum NaCl concentration for growth of 0-5?% (w/v). The isolate had sparse aerial mycelium and produced bud-shaped spores at the end of the aerial mycelium on ISP medium 4. The isolate contained ll-diaminopimelic acid as the diagnostic diamino acid and ribose as the major whole-cell sugar. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol mannoside, one unidentified phospholipid and three unidentified glycolipids. The predominant menaquinones were MK-9(H6), MK-9(H8) and MK-9(H4). The major fatty acids were iso-C16?:?0, anteiso-C17?:?0 and anteiso-C15?:?0. The G+C content of the DNA was 74.4 mol%. Phylogenetic analysis showed that strain TRM 46012(T) had 16S rRNA gene sequence similarity of 95.7?% with the most closely related species with a validly published name, Streptomyces cheonanensis, and it could be distinguished from all species in the genus Streptomyces by using the data from this polyphasic taxonomic study. On the basis of these data, strain TRM 46012(T) should be designated as a representative of a novel species of the genus Streptomyces, for which the name Streptomyces aidingensis sp. nov. is proposed. The type strain is TRM 46012(T) (?=?CGMCC 4.5739(T)?=?NBRC 108211(T)). PMID:23456804

Xia, Zhan-Feng; Ruan, Ji-Sheng; Huang, Ying; Zhang, Li-Li

2013-03-01

331

Rheinheimera tangshanensis sp. nov., a rice root-associated bacterium.  

PubMed

A Gram-negative, aerobic, rod-shaped bacterium, designated strain JA3-B52(T), was isolated from the roots of fresh rice plants (Oryza sativa). The cells were motile by means of polar single or lateral flagella. The colonies were non-pigmented. On the basis of 16S rRNA gene sequence comparisons, the strain was phylogenetically related to species of the genus Rheinheimera, having the greatest level of sequence similarity with respect to Rheinheimera texasensis A62-14B(T) (97.16 %). The bacterium grew at temperatures from 10 to 37 degrees C, with an optimum at 30 degrees C. The strain exhibited growth with 0-3.0 % (w/v) NaCl and at pH 6.0-8.5. The main cellular fatty acids were C(16 : 1)omega7c, C(17 : 1)omega8c, C (16 : 0), C(18 : 1)omega7c and C(12 : 0) 3-OH. The DNA G+C content was 47.0 mol%. The levels of similarity between the 16S rRNA gene sequence of strain JA3-B52(T) and those of the type strains of Rheinheimera species ranged from 95.38 to 97.16 %. The mean level of DNA-DNA relatedness between strain JA3-B52(T) and R. texasensis A62-14B(T), the strain most closely related to the isolate, was 20.4 %. On the basis of physiological and biochemical characteristics and genotypic data obtained in this work, strain JA3-B52(T) represents a novel species of the genus Rheinheimera, for which the name Rheinheimera tangshanensis sp. nov. is proposed. The type strain is JA3-B52(T) (=CGMCC 1.6362(T) =DSM 19460(T)). PMID:18842867

Zhang, Xiaoxia; Sun, Lei; Qiu, Fubin; McLean, Robert J C; Jiang, Ruibo; Song, Wei

2008-10-01

332

Albimonas pacifica sp. nov., isolated from seawater of the Pacific, and emended description of the genus Albimonas.  

PubMed

A Gram-stain-negative, aerobic, catalase- and oxidase-positive, non-flagellated, rod-shaped bacterium, designated strain P-50-3(T), was isolated from seawater of the Pacific. The strain grew at 10-40 °C (optimum at 30 °C) and with 0-12?% (w/v, optimum 2?%) NaCl. It reduced nitrate to nitrite but did not hydrolyse gelatin, starch or Tween 80. Analysis of 16S rRNA gene sequences showed that strain P-50-3(T) clustered tightly with the genus Albimonas and shared the highest 16S rRNA gene sequence similarity (94.3?%) with the type strain of Albimonas donghaensis. The major respiratory quinone was Q-10 and the major cellular fatty acids were C18?:?1?7c, C18?:?0, 11-methyl C18?:?1?7c and C16?:?0. Polar lipids included phosphatidylglycerol (PG), phosphatidylcholine (PC), two unidentified aminolipids and an unidentified lipid. The genomic DNA G+C content of strain P-50-3(T) was 69.0 mol%. On the basis of the data obtained in this polyphasic study, strain P-50-3(T) represents a novel species within the genus Albimonas, for which the name Albimonas pacifica sp. nov. is proposed. The type strain of Albimonas pacifica is P-50-3(T) (?=?KACC 16527(T)?=?CGMCC 1.11030(T)). An emended description of the genus Albimonas Lim et al. 2008 is also proposed. PMID:23606476

Li, Guo-Wei; Zhang, Xi-Ying; Wang, Chun-Sheng; Zhang, Yan-Jiao; Xu, Xue-Wei; Liu, Chang; Li, Hai; Liu, Ang; Xu, Zhong; Song, Xiao-Yan; Chen, Xiu-Lan; Zhou, Bai-Cheng; Zhang, Yu-Zhong

2013-04-19

333

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

2011-07-29

334

Paenibacillus typhae sp. nov., isolated from roots of Typha angustifolia L.  

PubMed

A Gram-stain-positive, facultatively anaerobic and rod-shaped bacterium, designated strain xj7(T), was isolated from roots of Typha angustifolia L. growing in Beijing Cuihu Wetland, China. The isolate was identified as a member of the genus Paenibacillus based on phenotypic characteristics and phylogenetic inference. The novel strain was spore-forming, motile, catalase-positive and oxidase-negative. Optimal growth of strain xj7(T) occurred at 28-30 °C and pH 7.0-7.5. Diphosphatidylglycerol was the most abundant polar lipid and occurred along with phosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid and three unknown aminophospholipids. The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The predominant isoprenoid quinone was MK-7. The major fatty acid components were anteiso-C15?:?0 (56.1?%), iso-C16?:?0 (9.1?%), C16?:?0 (8.0?%), iso-C14?:?0 (6.3?%) and iso-C15?:?0 (5.1?%). The G+C content of genomic DNA was 47.9 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain xj7(T) fell within the evolutionary radiation encompassed by the genus Paenibacillus, its closest neighbours were Paenibacillus borealis KK19(T) (97.5?%) and Paenibacillus durus DSM 1735(T) (97.1?%). However, the DNA-DNA relatedness values between strain xj7(T) and P. borealis KK19(T) and between strain xj7(T) and P. durus DSM 1735(T), were both 35?%. Based on phenotypic, chemotaxonomic and phylogenetic properties, strain xj7(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus typhae sp. nov. is proposed. The type strain is xj7(T) (?=?CGMCC 1.11012(T)?=?DSM 25190(T)). PMID:22707528

Kong, Bi He; Liu, Qun Fang; Liu, Min; Liu, Yang; Liu, Lei; Li, Chun Li; Yu, Rong; Li, Yan Hong

2012-06-15

335

Halopelagius longus sp. nov., a member of the family Halobacteriaceae isolated from a salt mine, and emended description of the genus Halopelagius.  

PubMed

A thermotolerant, extremely halophilic archaeon, BC12-B1(T), was isolated from a salt mine in Baicheng county, Xinjiang province, China. Colonies were off-white-grey. The cells stained Gram-negative, were motile and irregularly long-rod-shaped (variation in both width and length) with abundant gas vesicles. The strain was able to grow at 20-55 °C (optimum, 48 °C), at pH 6.0-8.0 (optimum, 7.0-7.3), with 1.8-6.0 M NaCl (optimum, 3.0-3.5 M) and with 0.02-2.2 M Mg(2+) (optimum, 0.1-0.2 M). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 8?% (w/v). Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain BC12-B1(T) was most closely related to Halopelagius inordinatus RO5-2(T) (98.5?%) with less than 95?% sequence similarity to other described species. The genomic DNA G+C content of strain BC12-B1(T) was 64.0 mol%. The DNA-DNA hybridization value between strain BC12-B1(T) and Hpl. inordinatus RO5-2(T) was 43.6?%. The major polar lipids of strain BC12-B1(T) were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, four glycolipids and an unknown lipid. Based on phenotypic, chemotaxonomic and genotypic characteristics, strain BC12-B1(T) represents a novel species of the genus Halopelagius, for which the name Halopelagius longus sp. nov. is proposed. The type strain is BC12-B1(T) (?=?CGMCC 1.12397(T)?=?JCM 18758(T)). An emended description of the genus Halopelagius is also provided. PMID:23584287

Zhang, Xin; Zhang, Wei-Yan; Shen, Ai-Hua; Huo, Ying-Yi; Zhu, Xu-Fen; Wu, Min

2013-04-12

336

Reclassification of Leifsonia ginsengi (Qiu et al. 2007) as Herbiconiux ginsengi gen. nov., comb. nov. and description of Herbiconiux solani sp. nov., an actinobacterium associated with the phyllosphere of Solanum tuberosum L.  

PubMed

In the context of studying the effects of transgenic fructan-producing potatoes on the community structure of phyllosphere bacteria, a group of strains closely related to the species Leifsonia ginsengi was isolated. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the new isolates and L. ginsengi DSM 19088(T) formed a lineage at the genus level and this finding was supported by chemotaxonomic characterization. The peptidoglycan type of the representative isolate, K134/01(T), and L. ginsengi DSM 19088(T) was B2?, with d- and l-diaminobutyric acid as the diagnostic diamino acid and glycine, alanine and threo-3-hydroxyglutamic acid. The almost-complete substitution of glutamic acid by threo-3-hydroxyglutamic acid supported the differentiation of the new strains from recognized species of the genus Leifsonia. Furthermore, the detection of substantial amounts of the fatty acid cyclohexyl-C(17 : 0) in the new isolates and L. ginsengi DSM 19088(T) was a prominent chemotaxonomic feature for a clear demarcation of these strains from all genera of the family Microbacteriaceae that display the B2? cell-wall type. Comparative phylogenetic and phenotypic analyses of the isolates and L. ginsengi DSM 19088(T) revealed the separate species status of the isolates. On the basis of these results, it is proposed that L. ginsengi should be classified as the type species of a novel genus, Herbiconiux gen. nov., with the name Herbiconiux ginsengi gen. nov., comb. nov. (type strain wged11(T)?=?CGMCC 4.3491(T)?=?JCM 13908(T)?=?DSM 19088(T)?=?NBRC 104580(T)). The phyllosphere isolates are assigned to a novel species, Herbiconiux solani sp. nov. (type strain K134/01(T)?=?DSM 19813(T)?=?LMG 24387(T)?=?NBRC 106740(T)). PMID:20511458

Behrendt, Undine; Schumann, Peter; Hamada, Moriyuki; Suzuki, Ken-Ichiro; Spröer, Cathrin; Ulrich, Andreas

2010-05-28

337

Pleomorphobacterium xiamenense gen. nov., sp. nov., a moderate thermophile isolated from a terrestrial hot spring.  

PubMed

An aerobic, motile, moderately thermophilic rod, designated strain CLW(T), was isolated from a terrestrial hot spring in an exposition garden in Xiamen City, Fujian Province, the People's Republic of China. Strain CLW(T) formed beige, dry colonies on solid 2216E medium and flocks in liquid medium. Cells were Gram-stain-negative, short rods (1.0-3.0 µm long and 0.4-0.6 µm wide) with six or more polar flagella. The temperature and pH for growth of strain CLW(T) were 28-65 °C (optimum, 50-58 °C) and pH 5.5-9.5 (optimum, pH 6.0-8.0). Growth occurred in the presence of 0.3-6.0?% NaCl (optimum 2.5-4.5?%). Phylogenetic analysis based on 16S rRNA gene sequences showed that the closest relative of the isolate was Amaricoccus kaplicensis Ben 101(T) (94.3?% sequence similarity). The DNA G+C content of strain CLW(T) was 72.2 mol%. The respiratory quinone was ubiquinone 10. The predominant polar lipids consisted of phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids (>10?%) were summed feature 8 (consisting of C18?:?1?7c and/or C18?:?1?6c), C18?:?1?7c 11-methyl and C18?:?0. Based on phylogenetic, physiological and biochemical data and DNA G+C content, strain CLW(T) is considered to represent a novel species of a new genus in the family Rhodobacteraceae, for which the name Pleomorphobacterium xiamenense gen. nov., sp. nov. is proposed. The type strain of the type species is CLW(T) (?=?LMG 26245(T)?=?CGMCC 1.10808(T)?=?MCCC 1A06272(T)). PMID:23041633

Yin, Decui; Chen, Liwei; Ao, Jingqun; Ai, Chunxiang; Chen, Xinhua

2012-10-05

338

Anoxybacillus vitaminiphilus sp. nov., a strictly aerobic and moderately thermophilic bacterium from the Puge hot spring in southwest China.  

PubMed

A strictly aerobic, Gram-positive, motile and spore-forming bacterium, strain 3nP4(T), was isolated from the Puge hot spring located in the southwestern geothermal area of China. Strain 3nP4(T) grew within the ranges of 38-66 °C (optimum 57-60 °C), pH 6.0 to 9.3 (optimum 7.0-7.5) and 0-4% (w/v) NaCl (optimum 0-0.5%). Phylogenetic analysis of 16S rRNA gene sequences, as well as the levels of DNA-DNA relatedness indicated that the new isolate represents a novel species of the genus Anoxybacillus with closest relation to Anoxybacillus voinovskiensis DSM 12111(T). Strain 3nP4(T) had DPG (diphosphatidylglycerol), PG (phosphatidylglycerol), PE (phosphatidylethanolamine), and one phospholipid (PL1) as major polar lipids and had iso-branched C15:0 and C17:0 as major fatty acids, which are both typical chemotaxonomic characteristics of the genus Anoxybacillus. The DNA G+C content of strain 3nP4(T) was 39.2±0.95 mol% (HPLC). Extremely reliant on vitamin mixture or yeast extract for growth is the most distinctive characteristic of the new isolate. Based on the polyphasic taxonomic characteristics, we have concluded that strain 3nP4(T) (= CGMCC 1.8979(T) = JCM 16594(T)) represents a novel species of the genus Anoxybacillus with suggested name Anoxybacillus vitaminiphilus sp. nov. PMID:23728374

Zhang, Xin-Qi; Zhang, Zhen-Li; Wu, Nan; Zhu, Xu-Fen; Wu, Min

2013-05-31

339

Bradyrhizobium huanghuaihaiense sp. nov., an effective symbiotic bacterium isolated from soybean (Glycine max L.) nodules.  

PubMed

In a survey of the biodiversity and biogeography of rhizobia associated with soybean (Glycine max L.) in different sites of the Northern (Huang-Huai-Hai) Plain of China, ten strains were defined as representing a novel genomic species in the genus of Bradyrhizobium. They were distinguished from defined species in restriction fragment length polymorphism (RFLP) analysis of the 16S rRNA gene and the 16S-23S rRNA gene intergenic spacer (IGS). In BOX-PCR, these strains presented two patterns that shared 94% similarity, demonstrating that they were a homogenous group with limited diversity. In phylogenetic analyses of the 16S rRNA gene, IGS and housekeeping gene sequences, four representative strains formed a distant lineage within the genus Bradyrhizobium, which was consistent with the results of DNA-DNA hybridization. The strains of this novel group formed effective nodules with G. max, Glycine soja and Vigna unguiculata in cross-nodulation tests and harboured symbiotic genes (nodC and nifH) identical to those of reference strains of Bradyrhizobium japonicum, Bradyrhizobium liaoningense and 'Bradyrhizobium daqingense' originating from soybean, implying that the novel group may have obtained these symbiotic genes by lateral gene transfer. In analyses of cellular fatty acids and phenotypic features, some differences were found between the novel group and related Bradyrhizobium species, demonstrating that the novel group is distinct phenotypically from other Bradyrhizobium species. Based upon the data obtained, these strains are proposed to represent a novel species, Bradyrhizobium huanghuaihaiense sp. nov., with CCBAU 23303(T) (?=?LMG 26136(T) ?=?CGMCC 1.10948(T) ?=?HAMBI 3180(T)) as the type strain. The DNA G+C content of strain CCBAU 23303(T) is 61.5 mol% (T(m)). PMID:22003042

Zhang, Yan Ming; Li, Ying; Chen, Wen Feng; Wang, En Tao; Sui, Xin Hua; Li, Qin Qin; Zhang, Yun Zeng; Zhou, Yu Guang; Chen, Wen Xin

2011-10-14

340

Gracilibacillus xinjiangensis sp. nov., a new member of the genus Gracilibacillus isolated from Xinjiang region, China.  

PubMed

A Gram-positive, endospore-forming, rod-shaped bacterium, designated isolate J2(T) was isolated from a soil sample from Xinjiang Uyghur Autonomous Region, China. The isolate was observed to grow at 16-46 °C and pH 6.5-8.0. Chemotaxonomic analysis showed menaquinone-7 (MK-7) to be the major isoprenoid quinone; diphosphatidylglycerol, phosphatidylglycerol, one aminophospholipid, two phosphoglycolipids and one glycolipid as the major cellular polar lipids; and anteiso-C15:0, iso-C15:0, anteiso-C17:0 and C16:0 as the major fatty acids. Comparative analyses of the 16S rRNA gene sequence showed that strain J2(T) is most closely related to Gracilibacillus ureilyticus (with 98.8 % similarity), Gracilibacillus dipsosauri (97.2 %), Gracilibacillus quinghaiensis (97.1 %) and Gracilibacillus thailandensis (97.0 %). The DNA-DNA reassociation values between strain J2(T) and G. ureilyticus MF38(T), G. dipsosauri DD1(T), G. quinghaiensis YIM-C229(T) and G. thailandensis TP2-8(T) were 29.8 ± 3.7, 23.0 ± 3.5, 15.8 ± 4.9 and 15.9 ± 5.0 %, respectively. The genomic DNA G+C content of strain J2(T) was determined to be 36.5 mol%. Based on these data, strain J2(T) is considered as a novel species of the genus Gracilibacillus, for which the name Gracilibacillus xinjiangensis sp. nov. is proposed. The type species is J2(T) (= CGMCC 1.12449(T) = JCM 18859(T)). PMID:23921649

Yang, Na; Ren, Biao; Dai, Huanqin; Liu, Zhiheng; Zhou, Yuguang; Song, Fuhang; Zhang, Lixin

2013-08-07

341

Paenibacillus tianmuensis sp. nov., isolated from soil.  

PubMed

Two closely related, Gram-stain-negative, rod-shaped, spore-forming strains, B27(T) and F6-B70, were isolated from soil samples of Tianmu Mountain National Natural Reserve in Zhejiang, China. Phylogenetic analysis based on 16S rRNA gene and rpoB sequences indicated that the isolates were members of the genus Paenibacillus. Both isolates were closely related to Paenibacillus ehimensis IFO 15659(T), Paenibacillus elgii SD17(T) and Paenibacillus koreensis YC300(T) (? 95.2 % 16S rRNA gene sequence similarity). DNA-DNA relatedness between strain B27(T) and P. ehimensis DSM 11029(T), P. elgii NBRC 100335(T) and P. koreensis KCTC 2393(T) was 21.2, 28.6 and 16.8 %, respectively. The major cellular fatty acids of strains B27(T) and F6-B70 were anteiso-C(15 : 0) and iso-C(15 : 0). The cell wall contained meso-diaminopimelic acid. The two isolates differed from their closest neighbours in terms of phenotypic characteristics and cellular fatty acid profiles (such as variable for oxidase, negative for methyl red test, unable to produce acid from d-fructose and glycogen and relatively higher amounts of iso-C(15 : 0) and lower amounts of C(16 : 0) and iso-C(16 : 0)). Strains B27(T) and F6-B70 represent a novel species of the genus Paenibacillus, for which the name Paenibacillus tianmuensis sp. nov. is proposed. The type strain is B27(T) (?=?DSM 22342(T) ?=?CGMCC 1.8946(T)). PMID:20543152

Wu, Xuechang; Fang, Haihuan; Qian, Chaodong; Wen, Yanping; Shen, Xiaobo; Li, Ou; Gao, Haichun

2010-06-11

342

Halogranum rubrum gen. nov., sp. nov., a halophilic archaeon isolated from a marine solar saltern.  

PubMed

Two extremely halophilic archaea, strains RO2-11(T) and HO2-1, were isolated from two Chinese marine solar salterns, Rudong solar saltern and Haimen solar saltern, respectively. Cells of the two strains were polymorphic and Gram-stain-negative; colonies were red-pigmented. The two strains grew at NaCl concentrations of 2.6-4.3 M (optimum 3.9 M) and required at least 0.1 M Mg2+ for growth. They were able to grow over a pH range of 6.0-8.0 and a temperature range of 20-50 degrees C, with optimal pH of 7.5 and optimal temperature of 37 degrees C. The major polar lipids of strain RO2-11(T) and strain HO2-1 were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and three glycolipids, two of them chromatographically identical to S-DGD-1 and DGD-1, the third unidentified. The 16S rRNA gene sequence similarity of strain RO2-11(T) and strain HO2-1 was 99.3 % and highest sequence similarity with the closest relative (Haloferax larsenii) was 91.4 %. Based on the data obtained, the two isolates could not be classified in any recognized genus of the family Halobacteriaceae. Strain RO2-11(T) and strain HO2-1 are thus considered to represent a novel species of a new genus within the family Halobacteriaceae, for which the name Halogranum rubrum gen. nov., sp. nov. is proposed. The type strain is RO2-11(T) (=CGMCC 1.7738(T) =JCM 15772(T)). PMID:19671729

Cui, Heng-Lin; Gao, Xia; Sun, Fang-Fang; Dong, Ying; Xu, Xue-Wei; Zhou, Yu-Guang; Liu, Hong-Can; Oren, Aharon; Zhou, Pei-Jin

2009-08-11

343

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

2009-10-23

344

Amphibacillus jilinensis sp. nov., a facultatively anaerobic, alkaliphilic bacillus from a soda lake.  

PubMed

A facultatively anaerobic, alkaliphilic, spore-forming, Gram-positive-staining rod, designated Y1(T), was isolated under strictly anaerobic conditions from sediment of a soda lake in Jilin province, China. The strain was not dependent on Na(+) but was highly halotolerant and grew optimally in medium JY with 0.5 M Na(+) (0.06 M NaHCO(3) and 0.44 M NaCl). The optimum pH for growth was 9.0, with a range of pH 7.5-10.5. No growth occurred at pH 7.0 or 11.0. The strain was mesophilic, with a temperature range of 15-45 °C and optimum growth at 32 °C. Strain Y1(T) was able to use certain mono- and oligosaccharides. Soluble starch and casein were hydrolysed. The methyl red test, Voges-Proskauer test and tests for catalase and oxidase activities were negative. The predominant fatty acids were anteiso-C(15?:?0) and iso-C(15?:?0). Comparative 16S rRNA gene sequence analysis revealed 93.4-96.8?% sequence similarity to members of the genus Amphibacillus. The DNA G+C content was 37.7 mol% (T(m) method). The DNA-DNA relatedness of strain Y1(T) with respect to Amphibacillus tropicus DSM 13870(T) and Amphibacillus sediminis DSM 21624(T) was 48 and 37?%, respectively. On the basis of its phylogenetic position and the DNA-DNA relatedness data as well as its physiological and biochemical properties, strain Y1(T) represents a novel species of the genus Amphibacillus, for which the name Amphibacillus jilinensis sp. nov. is proposed. The type strain is Y1(T) (=CGMCC 1.5123(T) =JCM 16149(T)). PMID:19965990

Wu, Xiao-Yue; Zheng, Gang; Zhang, Wen-Wu; Xu, Xue-Wei; Wu, Min; Zhu, Xu-Fen

2009-12-04

345

Haloterrigena daqingensis sp. nov., an extremely haloalkaliphilic archaeon isolated from a saline-alkaline soil.  

PubMed

A haloalkaliphilic archaeon, strain JX313(T), was isolated from a saline-alkaline soil from Daqing, Heilongjiang Province, China. Its morphological, physiological and biochemical features and 16S rRNA gene sequence were determined. Colonies of the strain were orange-red and cells were non-motile cocci and Gram-stain-variable. The strain required at least 1.7 M NaCl for growth, with optimal growth occurring in 2.0-2.5 M NaCl. Growth was observed at 20-50°C and pH 8.0-10.5, with optimal growth at 35°C and pH 10.0. The G+C content of its genomic DNA was 59.3 mol%. Phylogenetic analysis of 16S rRNA gene sequences showed that strain JX313(T) is associated with the genera Haloterrigena and Natrinema and is most closely related to Haloterrigena salina XH-65(T) (96.2? % sequence similarity) and Haloterrigena hispanica FP1(T) (96.2?%). DNA-DNA hybridization experiments revealed that the relatedness of strain JX313(T) to type strains of related species of the genus Haloterrigena or Natrinema was less than 50?%. Furthermore, the cellular polar lipids of strain JX313(T), identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and mannose-2,6-disulfate (1?2)-glucose glycerol diether (S?-DGD), were consistent with the polar lipid characteristics of the genus Haloterrigena. Therefore, phylogenetic analysis, phenotypic assessment and chemotaxonomic data showed that JX313(T) represents a novel species within the genus Haloterrigena, for which the name Haloterrigena daqingensis sp. nov. is proposed. The type strain is JX313(T) (=CGMCC 1.8909(T) =NBRC 105739(T)). PMID:19915113

Wang, Shuang; Yang, Qian; Liu, Zhi-Hua; Sun, Lei; Wei, Dan; Zhang, Jun-Zheng; Song, Jin-Zhu; Yuan, Hai-Feng

2009-11-13

346

Bacillus daliensis sp. nov., an alkaliphilic, Gram-positive bacterium isolated from a soda lake.  

PubMed

A Gram-positive, alkaliphilic bacterium, designated strain DLS13T, was isolated from Dali Lake in Inner Mongolia Autonomous Region, China. The isolate was able to grow at pH 7.5-11.0 (optimum at pH 9), in 0-8?% (w/v) NaCl (optimum at 2?%, w/v) and at 10-45 °C (optimum at 30 °C). Cells of the isolate were facultatively anaerobic, spore-forming rods with peritrichous flagella. The predominant isoprenoid quinone was MK-7 and its cell wall peptidoglycan contained meso-diaminopimelic acid. The major polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. The major cellular fatty acids were anteiso-C15:0, anteiso-C17:0 and iso-C15:0. The genomic DNA G+C content of the isolate was 43.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain DLS13T was a member of the genus Bacillus and most closely related to Bacillus saliphilus DSM 15402T (96.9?% similarity). The DNA-DNA relatedness value between strain DLS13T and B. saliphilus DSM 15402T was 38.7±1.9?%. Comparative analysis of genotypic and phenotypic features indicated that strain DLS13T represents a novel species of the genus Bacillus, for which the name Bacillus daliensis sp. nov. is proposed; the type strain is DLS13T (=CGMCC 1.10369T=JCM 17097T=NBRC 107572T). PMID:21669916

Zhai, Lei; Liao, Tingting; Xue, Yanfen; Ma, Yanhe

2011-06-13

347

Pustulibacterium marinum gen. nov., sp. nov., a member of the family Flavobacteriaceae isolated from the Bashi Channel.  

PubMed

A Gram-reaction-negative, non-spore-forming, gliding, non-translucent, colourless or yellow, aerobic and elevated-colony-forming strain, designated E403(T), was isolated from the Bashi Channel and subjected to a polyphasic taxonomic study. Strain E403(T) could grow in the presence of 0.3-8 % (w/v) NaCl, at 16-43 °C and at pH 6-9, and grew optimally at 28 °C, pH 8, in natural seawater medium. The respiratory quinones were MK-6 and MK-7. The major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 1 G, summed feature 3 (C16 : 1?7c/C16 : 1?6c), iso-C15 : 0 3-OH and C16 : 0. The DNA G+C content of strain E403(T) was 37.9 mol%. Phylogenetic analyses based on 16S rRNA gene sequences of members of the family Flavobacteriaceae showed that strain E403(T) formed a distinct evolutionary lineage within the stable cluster containing type strains Zhouia amylolytica HN-171(T) (92.2 % similarity) and Joostella marina En5(T) (92.4 % similarity). In addition to the large 16S rRNA gene sequence differences, E403(T) can also be distinguished from the reference type strains J. marina En5(T) and Sinomicrobium oceani SCSIO 03483(T) by several phenotypic characteristics and chemotaxonomic properties. On the basis of phenotypic, chemotaxonomic and phylogenetic properties, strain E403(T) is suggested to represent a novel species of a new genus in the family Flavobacteriaceae, for which the name Pustulibacterium marinum gen. nov., sp. nov. is proposed. The type strain is E403(T) (= CCTCC AB2012862(T) = CGMCC 1.12333(T) = KCTC 32192(T)). PMID:23416571

Wang, Guanghua; Zhou, Danyan; Dai, Shikun; Tian, Xinpeng; Li, Jie; Chen, Wen; Xiang, Wenzhou; Li, Xiang

2013-02-15

348

Ornithinimicrobium pekingense sp. nov., isolated from activated sludge.  

PubMed

The bacterial strain LW6(T) was isolated from activated sludge of a wastewater treatment bioreactor. Cells of strain LW6(T) are Gram-positive, irregular, short rods and cocci, 0.5-0.8x1.0-1.6 microm. Colonies are light-yellow, smooth, circular and 0.2-1.0 mm in diameter after 3 days incubation. Strain LW6(T) is aerobic and heterotrophic. It grows at a temperature range of 26-38 degrees C and pH range of 6-9, with optimal growth at 33-37 degrees C and pH 7.8-8.2. The predominant cellular fatty acids of strain LW6(T) are iso-C(15:0) (38.9%) and iso-C(17:1)omega9c (18.8%). Strain LW6(T) has the major respiratory menaquinones MK-8(H(4)) and MK-8(H(2)) and polar lipids phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol and unknown glycolipid/phospholipids. The cell wall peptidoglycan of strain LW6(T) contained the amino acids ornithine, lysine, glutamic acid, alanine, glycine and aspartic acid. Its molar DNA G+C content is 69 mol% (T(m)). Analysis of 16S rRNA gene sequences indicated that strain LW6(T) was related phylogenetically to members of the genus Ornithinimicrobium, with similarities ranging from 98.3 to 98.7%. The DNA-DNA relatedness of strain LW6(T) to Ornithinimicrobium humiphilum DSM 12362(T) and Ornithinimicrobium kibberense K22-20(T) was respectively 31.5 and 15.2%. Based on these results, it is concluded that strain LW6(T) represents a novel species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium pekingense sp. nov. is proposed. The type strain is strain LW6(T) (=CGMCC 1.5362(T) =JCM 14001(T)). PMID:18175694

Liu, Xing-Yu; Wang, Bao-Jun; Jiang, Cheng-Ying; Liu, Shuang-Jiang

2008-01-01

349

Enterobacter sacchari sp. nov., a nitrogen-fixing bacterium associated with sugar cane (Saccharum officinarum L.).  

PubMed

Five nitrogen-fixing bacterial strains (SP1(T), NN143, NN144, NN208 and HX148) were isolated from stem, root or rhizosphere soil of sugar cane (Saccharum officinarum L.) plants. Cells were Gram-negative, motile, rods with peritrichous flagella. DNA G+C content was 55.0 ± 0.5 mol%. Sequence determinations and phylogenetic analysis of 16S rRNA gene and rpoB indicated that the strains were affiliated with the genus Enterobacter and most closely related to E. radicincitans DSM 16656(T) and E. oryzae LMG 24251(T). Fluorimetric determination of thermal denaturation temperatures after DNA-DNA hybridization, enterobacterial repetitive intergenic consensus PCR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry differentiated the whole-genome, genotype and protein profiles from those of E. radicincitans and E. oryzae. The strains' cell fatty acid composition differentiated them from E. radicincitans and E. oryzae by containing a higher level of summed feature 2 (C16 : 1?7c and/or C16 : 1?6c) and a lower level of C17 : 0 cyclo. Their physiological and biochemical profiles differentiated them from E. radicincitans by being positive for methyl red test, ornithine decarboxylase and utilization of putrescine, D-arabitol, L-fucose and methyl ?-D-glucoside and being negative for arginine dihydrolase, and differentiated them from E. oryzae by being positive for aesculin hydrolysis and utilization of putrescine, D-arabitol and L-rhamnose and being negative for arginine dihydrolase, lysine decarboxylase and utilization of mucate. The five strains therefore represent a novel species, for which the name Enterobacter sacchari sp. nov. is proposed, with the type strain SP1(T) ( = CGMCC 1.12102(T) = LMG 26783(T)). PMID:23291881

Zhu, Bo; Zhou, Qing; Lin, Li; Hu, Chunjin; Shen, Ping; Yang, Litao; An, Qianli; Xie, Guanlin; Li, Yangrui

2013-01-04

350

Streptomyces wuyuanensis sp. nov., an actinomycete from soil.  

PubMed

A novel actinomycete, strain FX61(T), was isolated from a saline sample collected from the Inner Mongolian Autonomous Region in China and subjected to a taxonomic study using a polyphasic approach. The predominant menaquinones were MK-9(H6), MK-9(H8) and MK-9(H4). The major fatty acids were iso-C16 : 0, anteiso-C15 : 0, iso-C15 : 0, iso-C16 : 1 H, C16 : 0, iso-C14 : 0 and anteiso-C17 : 0. The phospholipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, two phosphatidylinositol mannosides and an unidentified phospholipid. The G+C content of the genomic DNA was 72 mol%. The 16S rRNA gene sequence of the isolate had greater than 98 % similarity with those of Streptomyces griseoincarnatus ATCC 23623(T) (98.2 %), Streptomyces labedae DSM 41446(T) (98.2 %), Streptomyces variabilis ATCC 19815(T) (98.2 %), Streptomyces erythrogriseus ATCC 27427(T) (98.2 %), Streptomyces matensis ATCC 23935(T) (98.2 %), Streptomyces althioticus ATCC 19724(T) (98.2 %) and Streptomyces luteosporeus ATCC 33049(T) (98.0 %), showing that the novel strain should be assigned to the genus Streptomyces. DNA-DNA hybridizations with the seven above-mentioned members of the genus Streptomyces showed 29.8, 28.5, 27.0, 25.5, 25.0, 23.5 and 22.0 % relatedness, respectively. On the basis of the phenotypic characteristics and genotypic distinctiveness, strain FX61(T) should be classified as a novel species of the genus Streptomyces, for which the name Streptomyces wuyuanensis sp. nov. is proposed. The type strain is FX61(T) (= CGMCC 4.7042(T) = KCTC 29112(T)). PMID:23355697

Zhang, Xuefang; Zhang, Jianli; Zheng, Jimei; Xin, Di; Xin, Yuhua; Pang, Huancheng

2013-01-25

351

Syntrophomonas erecta subsp. sporosyntropha subsp. nov., a spore-forming bacterium that degrades short chain fatty acids in co-culture with methanogens.  

PubMed

Two obligate anaerobic bacterial strains (5-3-Z(T) and Y4-1) were isolated from river sediment and rice field mud, respectively. They degraded straight-chain fatty acids with 4-8 carbon atoms in syntrophic association with methanogens, however, neither tested branch-chain fatty acids nor could benzoate be degraded. The strains formed spores when cocultured with methanogens on butyrate, or when grew on butyrate plus dimethyl sulfoxide (DMSO) in pure culture. The cells were slightly curved rods with Gram-negative cell wall structure, and contained small amount of poly beta-hydroxyalkanoate. The strains could not degrade butyrate alone, nor could use fumarate, sulfate, thiosulfate, sulfur or nitrate as electron acceptors except DMSO for butyrate degradation. The generation time of strain 5-3-Z(T) was about 12h when growing on crotonate at 37 degrees C. The growth of the new strains occurred in the range of pH 5.5-8.4, and of temperature 20-48 degrees C, and at NaCl concentration of 0-700 mM. The G+C content of the genomic DNA of strain 5-3-Z(T) was 40.6mol%. Phylogenetic analysis based on 16S rRNA gene similarity showed the two strains to be a member of species Syntrophomonas erecta (98.4-98.9% sequence similarity), however they differed from the existing strains in both phenotypic and genetic characteristics. Therefore, a new subspecies of S. erecta, S. erecta subsp. sporosyntropha was proposed. The type strain was 5-3-Z(T) (=CGMCC1.5032(T)=JCM13344(T)). PMID:16455220

Wu, Chenggang; Liu, Xiaoli; Dong, Xiuzhu

2006-02-07

352

Adhesion mechanisms of plant-pathogenic Xanthomonadaceae.  

PubMed

The family Xanthomonadaceae is a wide-spread family of bacteria belonging to the gamma subdivision of the Gram-negative proteobacteria, including the two plant-pathogenic genera Xanthomonas and Xylella, and the related genus Stenotrophomonas. Adhesion is a widely conserved virulence mechanism among Gram-negative bacteria, no matter whether they are human, animal or plant pathogens, since attachment to the host tissue is one of the key early steps of the bacterial infection process. Bacterial attachment to surfaces is mediated by surface structures that are anchored in the bacterial outer membrane and cover a broad group of fimbrial and non-fimbrial structures, commonly known as adhesins. In this chapter, we discuss recent findings on candidate adhesins of plant-pathogenic Xanthomonadaceae, including polysaccharidic (lipopolysaccharides, exopolysaccharides) and proteineous structures (chaperone/usher pili, type IV pili, autotransporters, two-partner-secreted and other outer membrane adhesins), their involvement in the formation of biofilms and their mode of regulation via quorum sensing. We then compare the arsenals of adhesins among different Xanthomonas strains and evaluate their mode of selection. Finally, we summarize the sparse knowledge on specific adhesin receptors in plants and the possible role of RGD motifs in binding to integrin-like plant molecules. PMID:21557058

Mhedbi-Hajri, Nadia; Jacques, Marie-Agnès; Koebnik, Ralf

2011-01-01

353

Isolation and Identification of Cellulolytic Bacteria from the Gut of Holotrichia parallela Larvae (Coleoptera: Scarabaeidae).  

PubMed

In this study, 207 strains of aerobic and facultatively anaerobic cellulolytic bacteria were isolated from the gut of Holotrichia parallela larvae. These bacterial isolates were assigned to 21 genotypes by amplified ribosomal DNA restriction analysis (ARDRA). A partial 16S rDNA sequence analysis and standard biochemical and physiological tests were used for the assignment of the 21 representative isolates. Our results show that the cellulolytic bacterial community is dominated by the Proteobacteria (70.05%), followed by the Actinobacteria (24.15%), the Firmicutes (4.35%), and the Bacteroidetes (1.45%). At the genus level, Gram-negative bacteria including Pseudomonas, Ochrobactrum, Rhizobium, Cellulosimicrobium, and Microbacterium were the predominant groups, but members of Bacillus, Dyadobacter, Siphonobacter, Paracoccus, Kaistia, Devosia, Labrys, Ensifer, Variovorax, Shinella, Citrobacter, and Stenotrophomonas were also found. Furthermore, our results suggest that a significant amount of bacterial diversity exists among the cellulolytic bacteria, and that Siphonobacter aquaeclarae, Cellulosimicrobium funkei, Paracoccus sulfuroxidans, Ochrobactrum cytisi, Ochrobactrum haematophilum, Kaistia adipata, Devosia riboflavina, Labrys neptuniae, Ensifer adhaerens, Shinella zoogloeoides, Citrobacter freundii, and Pseudomonas nitroreducens are reported to be cellulolytic for the first time in this study. Our results indicate that the scarab gut is an attractive source for the study of novel cellulolytic microorganisms and enzymes useful for cellulose degradation. PMID:22489111

Huang, Shengwei; Sheng, Ping; Zhang, Hongyu

2012-02-23

354

Bacterial communities on food court tables and cleaning equipment in a shopping mall.  

PubMed

The food court at a shopping mall is a potential transfer point for pathogenic microbes, but to date, this environment has not been the subject of detailed molecular microbiological study. We used a combination of culture-based and culture-independent approaches to investigate the types and numbers of bacteria present on food court tables, and on a food court cleaning cloth. Bacteria were found at 10²-10? c.f.u./m² on food court tables and 10¹? c.f.u./m² on the cleaning cloth. Tag-pyrosequencing of amplified 16S rRNA genes revealed that the dominant bacterial types on the cleaning cloth were genera known to include pathogenic species (Stenotrophomonas, Aeromonas), and that these genera were also evident at lower levels on table surfaces, suggesting possible cross-contamination. The evidence suggests a public health threat is posed by bacteria in the food court, and that this may be due to cross-contamination between cleaning equipment and table surfaces. PMID:22995219

Dingsdag, S; Coleman, N V

2012-09-21

355

NeutroPhase® in chronic non-healing wounds  

PubMed Central

Chronic non-healing wounds, such as venous stasis ulcers, diabetic ulcers, and pressure ulcers are serious unmet medical needs that affect a patient’s morbidity and mortality. Common pathogens observed in chronic non-healing wounds are Staphylococcus including MRSA, Pseudomonas, Enterobacter, Stenotrophomonas, and Serratia spp. Topical and systemically administered antibiotics do not adequately decrease the level of bacteria or the associated biofilm in chronic granulating wounds and the use of sub-lethal concentrations of antibiotics can lead to resistant phenotypes. Furthermore, topical antiseptics may not be fully effective and can actually impede wound healing. We show 5 representative examples from our more than 30 clinical case studies using NeutroPhase® as an irrigation solution with chronic non-healing wounds with and without the technique of negative pressure wound therapy (NPWT). NeutroPhase® is pure 0.01% hypochlorous acid (i.e. >97% relative molar distribution of active chlorine species as HOCl) in a 0.9% saline solution at pH 4-5 and is stored in glass containers. NovaBay has three FDA cleared 510(k)s. Patients showed a profound improvement and marked accelerated rates of wound healing using NeutroPhase® with and without NPWT. NeutroPhase® was non-toxic to living tissues.

Crew, John; Varilla, Randell; Rocas, Thomas Allandale; Debabov, Dmitri; Wang, Lu; Najafi, Azar; Rani, Suriani Abdul; Najafi, Ramin (Ron); Anderson, Mark

2012-01-01

356

Exploration for facultative endosymbionts of glassy-wingedsharpshooter (Hemiptera: Cicadellidae)  

SciTech Connect

Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae),glassy-winged sharpshooter, was collected in California and severalstates in the southeastern United States in 2002 and 2003 and analyzedfor endosymbiotic bacteria. Hemolymph, eggs, and bacteriomes wereexamined for the presence of bacteria by polymerase chain reaction. Asubset of hemolymph and egg samples had their 16S rRNA gene ampliconscloned and sequenced or analyzed by restriction digest patterns ofsamples compared with known bacterial DNA. Baumannia cicadellinicola, oneof the primary symbionts of glassy-winged sharpshooter, was found in themajority of hemolymph samples, although it has been considered until nowto reside primarily inside the specialized host bacteriocytes. Wolbachiasp., a common secondary symbiont in many insect taxa investigated todate, was the second most frequently detected bacterium in hemolymphsamples. In addition, we detected bacteria that were most closely related(by 16S rRNA gene sequence) to Pseudomonas, Stenotrophomonas, andAcinetobacter in hemolymph samples of one and/or two glassy-wingedsharpshooters, but their origin is uncertain.

Montllor-Curley, C.; Brodie, E.L.; Lechner, M.G.; Purcell, A.H.

2006-07-01

357

Isolation and characterization of endophytic bacteria isolated from the leaves of the common bean (Phaseolus vulgaris)  

PubMed Central

The common bean is one of the most important legumes in the human diet, but little is known about the endophytic bacteria associated with the leaves of this plant. The objective of this study was to characterize the culturable endophytic bacteria of common bean (Phaseolus vulgaris) leaves from three different cultivars (Vermelhinho, Talismã, and Ouro Negro) grown under the same field conditions. The density of endophytic populations varied from 4.5 x 102 to 2.8 x 103 CFU g-1 of fresh weight. Of the 158 total isolates, 36.7% belonged to the Proteobacteria, 32.9% to Firmicutes, 29.7% to Actinobacteria, and 0.6% to Bacteroidetes. The three P. vulgaris cultivars showed class distribution differences among Actinobacteria, Alphaproteobacteria and Bacilli. Based on 16S rDNA sequences, 23 different genera were isolated comprising bacteria commonly associated with soil and plants. The genera Bacillus, Delftia, Methylobacterium, Microbacterium, Paenibacillus, Staphylococcus and Stenotrophomonas were isolated from all three cultivars. To access and compare the community structure, diversity indices were calculated. The isolates from the Talismã cultivar were less diverse than the isolates derived from the other two cultivars. The results of this work indicate that the cultivar of the plant may contribute to the structure of the endophytic community associated with the common bean. This is the first report of endophytic bacteria from the leaves of P. vulgaris cultivars. Future studies will determine the potential application of these isolates in biological control, growth promotion and enzyme production for biotechnology.

de Oliveira Costa, Leonardo Emanuel; de Queiroz, Marisa Vieira; Borges, Arnaldo Chaer; de Moraes, Celia Alencar; de Araujo, Elza Fernandes

2012-01-01

358

Characterization of Phragmites cummunis rhizosphere bacterial communities and metabolic products during the two stage sequential treatment of post methanated distillery effluent by bacteria and wetland plants.  

PubMed

This study deals with the characterization of rhizosphere bacterial communities and metabolic products produced during the two stage sequential treatment of post methanated distillery effluent by bacteria and constructed wetland plants. Results showed that bacterial treatment followed by wetland plants (Phragmites cummunis) resulted 94.5% and 96.0% reduction in BOD and COD values, respectively. The PCR-RFLP analysis showed the presence of Stenotrophomonas, Enterobacter, Pantoea, Acinetobacter and Klebsiella sp., as dominant rhizosphere bacterial communities which play an important role in degradation and decolorization of PMDE in wetland treatment system. Further, the LC-MS-MS and other spectrophotometric analysis have shown that most of the pollutants detected in untreated PMDE were diminished from bacteria and wetland plant treated PMDE indicating that bacteria and wetland plant rhizosphere microbes utilized them as carbon, nitrogen and energy source. While, methylbenzene, furfuryl alcohol, and 4-vinyl-2-methoxyphenol were detected as metabolites in bacteria and hexadecanol in wetland plant rhizosphere treated PMDE. PMID:22047662

Chandra, Ram; Bharagava, Ram Naresh; Kapley, Atya; Purohit, Hemant J

2011-10-10

359

Antibiotic resistance of bacteria isolated from the internal organs of edible snow crabs.  

PubMed

Antibiotic resistance and microbiota within edible snow crabs are important for the Chionoecetes (snow crab) fishing industry. We investigated these parameters using culture methods and antibiotic susceptibility tests with six internal organs from three species of Chionoecetes. Each sample revealed many unexpected microbial species within Chionoecetes internal organs. On the basis of 16S rRNA sequence analysis of 381 isolates, the most abundant genera identified in Chionoecetes opilio were Acinetobacter spp. (24%), Bacillus spp. (4%), Pseudomonas spp. (34%), Stenotrophomonas spp. (28%), and Agreia spp. (11%). In Chionoecetes sp. crabs, Acinetobacter spp. (23%), Bacillus spp. (12%), and Psychrobacter spp. (20%) were most prevalent, while Agreia spp. (11%), Bacillus spp. (31%), Microbacterium spp. (10%), Rhodococcus spp. (12%), and Agrococcus spp. (6%) were most abundant in C. japonicus. Our antibiotic resistance test found resistance to all nine antibiotics tested in 19, 14, and two of the isolates from C. opilio, Chionoecetes sp., and, C. japonicus respectively. Our results are the first to show that microbes with antibiotic resistance are widely distributed throughout the internal organs of natural snow crabs. PMID:23990916

Kim, Misoon; Kwon, Tae-Hyung; Jung, Su-Mi; Cho, Seung-Hak; Jin, Seon Yeong; Park, Nyun-Ho; Kim, Choong-Gon; Kim, Jong-Shik

2013-08-21

360

Defluorination of sodium fluoroacetate by bacteria from soil and plants in Brazil.  

PubMed

The aim of this work was to isolate and identify bacteria able to degrade sodium fluoroacetate from soil and plant samples collected in areas where the fluoroacetate-containing plants Mascagnia rigida and Palicourea aenofusca are found. The samples were cultivated in mineral medium added with 20?mmol?L(-1) sodium fluoroacetate. Seven isolates were identified by 16S rRNA gene sequencing as Paenibacillus sp. (ECPB01), Burkholderia sp. (ECPB02), Cupriavidus sp. (ECPB03), Staphylococcus sp. (ECPB04), Ancylobacter sp. (ECPB05), Ralstonia sp. (ECPB06), and Stenotrophomonas sp. (ECPB07). All seven isolates degraded sodium-fluoroacetate-containing in the medium, reaching defluorination rate of fluoride ion of 20?mmol?L(-1). Six of them are reported for the first time as able to degrade sodium fluoroacetate (SF). In the future, some of these microorganisms can be used to establish in the rumen an engineered bacterial population able to degrade sodium fluoroacetate and protect ruminants from the poisoning by this compound. PMID:22619595

Camboim, Expedito K A; Tadra-Sfeir, Michelle Z; de Souza, Emanuel M; Pedrosa, Fabio de O; Andrade, Paulo P; McSweeney, Chris S; Riet-Correa, Franklin; Melo, Marcia A

2012-04-24

361

Defluorination of Sodium Fluoroacetate by Bacteria from Soil and Plants in Brazil  

PubMed Central

The aim of this work was to isolate and identify bacteria able to degrade sodium fluoroacetate from soil and plant samples collected in areas where the fluoroacetate-containing plants Mascagnia rigida and Palicourea aenofusca are found. The samples were cultivated in mineral medium added with 20?mmol?L?1 sodium fluoroacetate. Seven isolates were identified by 16S rRNA gene sequencing as Paenibacillus sp. (ECPB01), Burkholderia sp. (ECPB02), Cupriavidus sp. (ECPB03), Staphylococcus sp. (ECPB04), Ancylobacter sp. (ECPB05), Ralstonia sp. (ECPB06), and Stenotrophomonas sp. (ECPB07). All seven isolates degraded sodium-fluoroacetate-containing in the medium, reaching defluorination rate of fluoride ion of 20?mmol?L?1. Six of them are reported for the first time as able to degrade sodium fluoroacetate (SF). In the future, some of these microorganisms can be used to establish in the rumen an engineered bacterial population able to degrade sodium fluoroacetate and protect ruminants from the poisoning by this compound.

Camboim, Expedito K. A.; Tadra-Sfeir, Michelle Z.; de Souza, Emanuel M.; Pedrosa, Fabio de O.; Andrade, Paulo P.; McSweeney, Chris S.; Riet-Correa, Franklin; Melo, Marcia A.

2012-01-01

362

Diversity of culturable root-associated/endophytic bacteria and their chitinolytic and aflatoxin inhibition activity of peanut plant in China.  

PubMed

A total of 72 isolates of root-associated/endophytic (RAE) bacteria were isolated from peanut plants grown in the main producing areas of 6 provinces in China. The 16S rRNA gene sequences of these isolates were determined and phylogenetic analyses revealed that 72 isolates belonged to the classes Bacilli (49 isolates) and Gammaproteobacteria (23 isolates). The majority of RAE bacteria in Bacilli belonged to 2 genera, Bacillus and Lysinibacillus (48 and 1) while those in Gammaproteobacteria belonged to the genera Enterobacter, Serratia, Stenotrophomonas, and Pseudomonas (7, 11, 3 and 2 isolates, respectively). This is the first report of Lysinibacillus xylanilyticus isolate as biocontrol agent against AFs. All of the selected RAE bacteria showed inhibitory activities against Aspergillus parasiticus (A. parasiticus) growth and/or aflatoxins (AFs) production by visual agar plate assay and tip culture method. Most of the RAE bacteria strains (96 % strains) were determined to have decreased mycelia growth or AFs production levels by >50 % (p < 0.05). Bacterial isolates were further characterized for chitinolytic activity and 22 strains (30 % strains) of identified RAE bacteria degraded colloidal chitin on the chitin medium plate. Ten selected chitinolytic RAE bacteria were tested for antifungal activity on peanuts and most of them significantly decreased mycelial growth and AFs production levels by >90 %. These results showed a wide distribution of biological control bacteria against AFs in Chinese peanut main producing areas and the selected RAE bacteria could potentially be utilized for the biocontrol of toxicogenic fungi. PMID:23108663

Wang, Kai; Yan, Pei-Sheng; Ding, Qing-Long; Wu, Qin-Xi; Wang, Zhong-Bo; Peng, Jie

2012-10-30

363

Isolation of oxalotrophic bacteria able to disperse on fungal mycelium.  

PubMed

A technique based on an inverted Petri dish system was developed for the growth and isolation of soil oxalotrophic bacteria able to disperse on fungal mycelia. The method is related to the 'fungal highways' dispersion theory in which mycelial fungal networks allow active movement of bacteria in soil. Quantification of this phenomenon showed that bacterial dispersal occurs preferentially in upper soil horizons. Eight bacteria and one fungal strain were isolated by this method. The oxalotrophic activity of the isolated bacteria was confirmed through calcium oxalate dissolution in solid selective medium. After separation of the bacteria-fungus couple, partial sequencing of the 16S and the ITS1 and ITS2 sequences of the ribosomal RNA genes were used for the identification of bacteria and the associated fungus. The isolated oxalotrophic bacteria included strains related to Stenotrophomonas, Achromobacter, Lysobacter, Pseudomonas, Agrobacterium, Cohnella, and Variovorax. The recovered fungus corresponded to Trichoderma sp. A test carried out to verify bacterial transport in an unsaturated medium showed that all the isolated bacteria were able to migrate on Trichoderma hyphae or glass fibers to re-colonize an oxalate-rich medium. The results highlight the importance of fungus-driven bacterial dispersal to understand the functional role of oxalotrophic bacteria and fungi in soils. PMID:24106816

Bravo, Daniel; Cailleau, Guillaume; Bindschedler, Saskia; Simon, Anaele; Job, Daniel; Verrecchia, Eric; Junier, Pilar

2013-10-10

364

The role of nutrients in the biodegradation of 2,4,6-trinitrotoluene in liquid and soil.  

PubMed

The widely used explosive 2,4,6-trinitrotoluene (TNT) has residues that are potentially explosive, toxic, and mutagenic. TNT and other explosives can be degraded by microorganisms; however, biostimulation is needed for process efficiency. To investigate the effectiveness of using biostimulation to degrade TNT, we added varying concentrations of a nutrient amendment consisting of inorganic salts, plant extracts, and molasses to soil and liquid media. For the inoculum we used a consortium of bacteria AM 06 that had exhibited the ability to degrade TNT and which had been previously isolated from explosives-contaminated soils. Phylogenetically, the clones clustered into seven different genera: Klebsiella, Raoultella, Serratia, Stenotrophomonas, Pseudoxanthomonas, Achromobacter and Pseudomonas. The addition of AM 06 consortium to a liquid environment along with 100% nutrient amendment decreased the amount of TNT (and its degradation products) by up to 90% after 14 days incubation. At the total amount of TNT was less than 100 mg/l, the concentration of TNT did not influence the amount of sugar consumed by the bacteria consortium. In soil media, the TNT degradation process was dependent on the concentration of nutrient amendment added. At higher initial concentrations of TNT (500 mg/kg), bioaugmentation (i.e., addition of bacteria inoculum) had a demonstrated effect, especially when nutrient concentrations of 50% and 100% were added to the soil. Findings of this study could further the understanding of the TNT biodegradation processes in water and soil and provide for optimization of the technological conditions for bioremediation. PMID:22245864

Muter, Olga; Potapova, Katrina; Limane, Baiba; Sproge, Kristine; Jakobsone, Ida; Cepurnieks, Guntis; Bartkevics, Vadims

2012-01-13

365

[Utility of pyrrolidonyl-arylamidase detection for typing Enterobacteriaceae and non-fermenting Gram-negative bacteria].  

PubMed

Detection of pyrrolidonyl-aryl-amidase activity (PYR) is an important tool to identify gram-positive cocci, such as staphylococci, enterococci, streptococci, and other related genera. However, only few studies evaluating its usefulness with gram-negative rods have been published. Thus, a prospective study including 542 and 215 unique clinical isolates of Enterobacteriaceae and non-fermentative gram-negative rods, respectively, was undertaken. Strains were identified by conventional methods. PYR test was performed using a commercial kit, according to the manufacturer recommendations. Positive results were uniformly obtained for the PYR test with the following species: Citrobacter spp, Klebsiella spp, Enterobacter aerogenes, Enterobacter agglomerans group, Serratia marcescens and S. odorifera. On the other hand, negative results were uniformly displayed by E. coli (including inactive E. coli), Protease group, Salmonellia spp, Shigella spp, Acinetobacter spp, Burkholderia (Pseudomonas) cepacia and Flavobacterium spp. Variable results were shown in Pseudomonas aeruginosa, Stenotrophomonas (xanthomonas) malthophilia, Kluyvera cryocrescens, and Enterobacter cloacae. PYR test proved to be a reliable and simple tool to rapidly distinguish certain species belonging to Enterobacteriaceae (ie. Citrobacter freundii from Salmonella spp, and inactive E. coli from K. ozaenae). Further studies, including a wide diversity of species, are required to assess usefulness of the PYR test for the identification of non-fermentative gram-negative rods. PMID:8850133

Nicola, F; Centorbi, H; Bantar, C; Smayevsky, J; Bianchini, H

366

Plant growth promoting bacteria in Brachiaria brizantha.  

PubMed

Brachiaria brizantha is considered one of the preferred fodders among farmers for having high forage yield and large production of root mass. The association of beneficial bacteria with these grasses can be very valuable in the recovery of the pasture areas with nutritional deficiency. With the aim of studying this possibility, we carried out the sampling of soil and roots of B. brizantha in three areas (Nova Odessa-SP, São Carlos-SP and Campo Verde-MT, Brazil). Seventy-two bacterial strains were isolated and used in tests to evaluate their biotechnological potential. Almost all isolates presented at least one positive feature. Sixty-eight isolates produced analogues of indole-3-acetic acid, ten showed nitrogenase activity when subjected to the method of increasing the concentration of total nitrogen (total N) in the culture medium and sixty-five isolates showed nitrogenase activity when subjected to acetylene reduction technique. The partial sequencing of 16S rRNA of these isolates allowed the identification of seven main groups, with the prevalence of those affiliated to the genus Stenotrophomonas (69 %). At the end, this work elected the strains C4 (Pseudomonadaceae) and C7 (Rhodospirillaceae) as promising organisms for the development of inoculants due to their higher nitrogenase activity. PMID:22987328

Silva, Mylenne Calciolari Pinheiro; Figueiredo, Aline Fernandes; Andreote, Fernando Dini; Cardoso, Elke Jurandy Bran Nogueira

2012-09-18

367

Hessian fly-associated bacteria: transmission, essentiality, and composition.  

PubMed

Plant-feeding insects have been recently found to use microbes to manipulate host plant physiology and morphology. Gall midges are one of the largest groups of insects that manipulate host plants extensively. Hessian fly (HF, Mayetiola destructor) is an important pest of wheat and a model system for studying gall midges. To examine the role of bacteria in parasitism, a systematic analysis of bacteria associated with HF was performed for the first time. Diverse bacteria were found in different developmental HF stages. Fluorescent in situ hybridization detected a bacteriocyte-like structure in developing eggs. Bacterial DNA was also detected in eggs by PCR using primers targeted to different bacterial groups. These results indicated that HF hosted different types of bacteria that were maternally transmitted to the next generation. Eliminating bacteria from the insect with antibiotics resulted in high mortality of HF larvae, indicating that symbiotic bacteria are essential for the insect to survive on wheat seedlings. A preliminary survey identified various types of bacteria associated with different HF stages, including the genera Enterobacter, Pantoea, Stenotrophomonas, Pseudomonas, Bacillus, Ochrobactrum, Acinetobacter, Alcaligenes, Nitrosomonas, Arcanobacterium, Microbacterium, Paenibacillus, and Klebsiella. Similar bacteria were also found specifically in HF-infested susceptible wheat, suggesting that HF larvae had either transmitted bacteria into plant tissue or brought secondary infection of bacteria to the wheat host. The bacteria associated with wheat seedlings may play an essential role in the wheat-HF interaction. PMID:21858016

Bansal, Raman; Hulbert, Scot; Schemerhorn, Brandi; Reese, John C; Whitworth, R Jeff; Stuart, Jeffrey J; Chen, Ming-Shun

2011-08-16

368

Plant-microbe interactions: identification of epiphytic bacteria and their ability to alter leaf surface permeability.  

PubMed

Bacteria were either isolated from leaf surfaces of Hedera helix or obtained from a culture collection in order to analyse their effect on barrier properties of isolated Hedera and Prunus laurocerasus cuticles. On the basis of the 16S rDNA sequences the genera of the six bacterial isolates from Hedera were identified as Pseudomonas sp., Stenotrophomonas sp. and Achromobacter. Water permeability of cuticles isolated from H. helix was measured before and after inoculation with the six bacterial strains. In addition water permeability of cuticles isolated from P. laurocerasus was measured before and after inoculation with the three bacterial strains Pseudomonas aeruginosa, Xanthomonas campestris and Corynebacterium fascians. Rates of water diffusing across isolated cuticles of both species significantly increased by up to 50% after inoculation with all bacterial strains. Obtained results show that epiphytic bacteria have the ability of increasing water permeability of Hedera and Prunus cuticles, which in turn should increase the availability of water and dissolved compounds in the phyllopshere. Consequently, living conditions in the habitat phyllosphere are improved. It can be concluded that the ability to change leaf surface properties will improve epiphytic fitness of leaf surface bacteria. PMID:15819920

Schreiber, Lukas; Krimm, Ursula; Knoll, Daniel; Sayed, Mohamed; Auling, Georg; Kroppenstedt, Reiner M

2005-05-01

369

Diversity of culturable chitinolytic bacteria from rhizospheres of agronomic plants in Japan.  

PubMed

A total of 100 isolates of chitinolytic bacteria were obtained from the rhizospheres of various agronomic plants, and the 16S rRNA gene sequences of these isolates were determined. Phylogenetic analyses revealed that 81 isolates belonged to the classes Betaproteobacteria (39 isolates) and Gammaproteobacteria (42 isolates). Of the remaining 19 isolates, 16 belonged to the phylum Firmicutes. Clustering analysis identified 6 and 3 operational taxonomic units (OTUs) in Gammaproteobacteria and Betaproteobacteria, respectively, at the genus level. The majority of chitinolytic bacteria in Gammaproteobacteria belonged to the genera Serratia, Stenotrophomonas, and Lysobacter (14, 15, and 7 isolates, respectively) while those in Betaproteobacteria belonged to the genus Mitsuaria (37 isolates). The 16 isolates placed in Firmicutes belonged to 2 genera, Paenibacillus and Bacillus (8 isolates each). The isolates in the remaining OTUs belonged to the genera Erwinia, Aeromonas, Pseudomonas, Achromobacter, Flavobacterium, and Microbacterium, in less abundance. These results showed a wide distribution of culturable chitinolytic bacteria in the rhizospheres of various agronomic plants. Considering the potential antagonistic activity of chitinolytic enzymes against phytopathogenic fungi, which is exhibited by fungal cell wall degradation, the above-mentioned native chitinolytic bacteria in rhizospheres could potentially be utilized for the biological control of soil-borne phytopathogenic fungi. PMID:21487197

Someya, Nobutaka; Ikeda, Seishi; Morohoshi, Tomohiro; Noguchi Tsujimoto, Masako; Yoshida, Takanobu; Sawada, Hiroyuki; Ikeda, Tsukasa; Tsuchiya, Kenichi

2011-01-01

370

[Isolation of two endophytic phenanthrene-degrading strains and their degradation capacity].  

PubMed

Two endophytic bacterial strains, which could degrade high concentration (up to 200 mg.L-1) of phenanthrene in liquid, were isolated from plants grown in PAHs-contaminated soils by the selective. enrichment culture. According to the results of morphology, physiology and the phylogenetic analyses of 16S rDNA sequence, stain P1 was identified as Stenotrophomonas sp. , and strain P3 was identified as Pseudomonas sp.. Two strains were aerobic bacteria, the degradation rates of phenanthrene (100 mg.L-1) by strain P1 and strain P3 were all greater than 90% at 28 degrees C on the rotation shaker at 150 r.min-1 for 7 days. The degradation rates of phenanthrene by two strains were greater than 70% when cultivated under the conditions as: 20-30 degrees C , pH 6-8, 0%-4% NaCl, 10-30 mL/100 mL inventory. It suggested that the optimum culture condition was: 30 degrees C, pH 7.0, NaCl< or =4% , inventory < or = 30 mL/100 mL flask. Through comprehensive comparison analyses on the degradation capacity of two strains, it showed that the tolerance of strain P1 to high temperature was higher than that of str ain P3, while the tolerance of strain P3 to pH change and anoxic condition was higher than that of strain P1. PMID:23668150

Ni, Xue; Liu, Juan; Gao, Yan-Zheng; Zhu, Xue-Zhu; Sun, Kai

2013-02-01

371

Weakening Effect of Cell Permeabilizers on Gram-Negative Bacteria Causing Biodeterioration  

PubMed Central

Gram-negative bacteria play an important role in the formation and stabilization of biofilm structures on stone surfaces. Therefore, the control of growth of gram-negative bacteria offers a way to diminish biodeterioration of stone materials. The effect of potential permeabilizers on the outer membrane (OM) properties of gram-negative bacteria was investigated and further characterized. In addition, efficacy of the agents in enhancing the activity of a biocide (benzalkonium chloride) was assessed. EDTA, polyethylenimine (PEI), and succimer (meso-2,3-dimercaptosuccinic) were shown to be efficient permeabilizers of the members of Pseudomonas and Stenotrophomonas genera, as indicated by an increase in the uptake of a hydrophobic probe (1-N-phenylnaphthylamine) and sensitization to hydrophobic antibiotics. Visualization of Pseudomonas cells treated with EDTA or PEI by atomic force microscopy revealed damage in the outer membrane structure. PEI especially increased the surface area and bulges of the cells. Topographic images of EDTA-treated cells were compatible with events assigned for the effect of EDTA on outer membranes, i.e., release of lipopolysaccharide and disintegration of OM structure. In addition, the effect of EDTA treatment was visualized in phase-contrast images as large areas with varying hydrophilicity on cell surfaces. In liquid culture tests, EDTA and PEI supplementation enhanced the activity of benzalkonium chloride toward the target strains. Use of permeabilizers in biocide formulations would enable the use of decreased concentrations of the active biocide ingredient, thereby providing environmentally friendlier products.

Alakomi, H.-L.; Paananen, A.; Suihko, M.-L.; Helander, I. M.; Saarela, M.

2006-01-01

372

Diversity and metabolic potential of culturable root-associated bacteria from Origanum vulgare in sub-Himalayan region.  

PubMed

Study of rhizospheric bacteria from important plants is very essential, as they are known to influence plant growth and productivity, and also produce industrially important metabolites. Origanum vulgare is a perennial medicinal aromatic plant rich in phenolic antioxidants. Present study investigates the diversity of culturable root-associated bacteria from this plant in Palampur, India, which constitutes a unique ecosystem due to high rain fall, wide temperature fluctuations and acidic soil. Both root endophytes and rhizospheric soil bacteria were isolated, which resulted in a total of 120 morphologically different isolates. They were found to group into 21 phylotypes based on restriction fragment length polymorphism analysis. Growth medium composition had significant effect on the diversity of the isolated bacterial populations. The isolates were characterized for various metabolic, plant growth promoting (PGP) and other biotechnologically useful activities, based on which they were clustered into groups by principal component analysis. Majority of the isolates belonged to ?-Proteobacteria and Firmicutes. Pseudomonas and Stenotrophomonas were the most dominant species and together constituted 27.5 % of the total isolates. Many isolates, especially ?-Proteobacteria, showed very high PGP activities. Few isolates exhibited very high antioxidant activity, which may find potential applications in food and health industries. Firmicutes were catabolically the most versatile group and produced several hydrolytic enzymes. To the best of our knowledge, it is the first study describing rhizospheric microbial community of O. vulgare. PMID:22927014

Bafana, Amit

2012-08-28

373

Culture-dependent and -independent molecular analysis of the bacterial community within uranium ore.  

PubMed

The bacterial community structure within a uranium ore was investigated using culture-dependent and -independent clone library analysis and denaturing gradient gel electrophoresis of 16S rRNA genes. The major aerobic heterotrophic bacteria were isolated and identified, and their resistance to uranium and other heavy metals was characterized. Together with near neutral pH, moderate organic carbon content, elevated U and other heavy metals (V, Ni, Mn, Cu, etc.), the ore showed high microbial counts and phylotype richness. The bacterial community mainly consisted of uncultured Proteobacteria, with the predominance of ? - over ? - and ? -subdivisions, along with Actinobacteria and Firmicutes. A phylogenetic study revealed that nearly one-third of the community was affiliated to as yet uncultured and unidentified bacteria having a closer relationship to Pseudomonas. Lineages of Burkholderiaceae and Moraxellaceae were relatively more abundant in the total community, while genera affiliated to Xanthomonadaceae and Microbacteriaceae and Exiguobacterium were detected in the culturable fraction. More than 50% of the bacterial isolates affiliated to Stenotrophomonas, Microbacterium, Acinetobacter, Pseudomonas and Enterobacter showed resistance to uranium and other heavy metals. The study showed for the first time that uranium ore harbors major bacterial groups related to organisms having a wide range of environmentally significant functional attributes, and the most abundant members are possibly new groups/taxa. These findings provide new insights into U-ore geomicrobiology that could be useful in biohydrometallurgy and bioremediation applications. PMID:21656801

Islam, Ekramul; Sar, Pinaki

2011-03-24

374

Pyrosequencing reveals the influence of organic and conventional farming systems on bacterial communities.  

PubMed

It has been debated how different farming systems influence the composition of soil bacterial communities, which are crucial for maintaining soil health. In this research, we applied high-throughput pyrosequencing of V1 to V3 regions of bacterial 16S rRNA genes to gain further insight into how organic and conventional farming systems and crop rotation influence bulk soil bacterial communities. A 2×2 factorial experiment consisted of two agriculture management systems (organic versus conventional) and two crop rotations (flax-oat-fababean-wheat versus flax-alfalfa-alfalfa-wheat) was conducted at the Glenlea Long-Term Crop Rotation and Management Station, which is Canada's oldest organic-conventional management study field. Results revealed that there is a significant difference in the composition of bacterial genera between organic and conventional management systems but crop rotation was not a discriminator factor. Organic farming was associated with higher relative abundance of Proteobacteria, while Actinobacteria and Chloroflexi were more abundant in conventional farming. The dominant genera including Blastococcus, Microlunatus, Pseudonocardia, Solirubrobacter, Brevundimonas, Pseudomonas, and Stenotrophomonas exhibited significant variation between the organic and conventional farming systems. The relative abundance of bacterial communities at the phylum and class level was correlated to soil pH rather than other edaphic properties. In addition, it was found that Proteobacteria and Actinobacteria were more sensitive to pH variation. PMID:23284808

Li, Ru; Khafipour, Ehsan; Krause, Denis O; Entz, Martin H; de Kievit, Teresa R; Fernando, W G Dilantha

2012-12-19

375

Pyrosequencing Reveals the Influence of Organic and Conventional Farming Systems on Bacterial Communities  

PubMed Central

It has been debated how different farming systems influence the composition of soil bacterial communities, which are crucial for maintaining soil health. In this research, we applied high-throughput pyrosequencing of V1 to V3 regions of bacterial 16S rRNA genes to gain further insight into how organic and conventional farming systems and crop rotation influence bulk soil bacterial communities. A 2×2 factorial experiment consisted of two agriculture management systems (organic versus conventional) and two crop rotations (flax-oat-fababean-wheat versus flax-alfalfa-alfalfa-wheat) was conducted at the Glenlea Long-Term Crop Rotation and Management Station, which is Canada’s oldest organic-conventional management study field. Results revealed that there is a significant difference in the composition of bacterial genera between organic and conventional management systems but crop rotation was not a discriminator factor. Organic farming was associated with higher relative abundance of Proteobacteria, while Actinobacteria and Chloroflexi were more abundant in conventional farming. The dominant genera including Blastococcus, Microlunatus, Pseudonocardia, Solirubrobacter, Brevundimonas, Pseudomonas, and Stenotrophomonas exhibited significant variation between the organic and conventional farming systems. The relative abundance of bacterial communities at the phylum and class level was correlated to soil pH rather than other edaphic properties. In addition, it was found that Proteobacteria and Actinobacteria were more sensitive to pH variation.

Li, Ru; Khafipour, Ehsan; Krause, Denis O.; Entz, Martin H.; de Kievit, Teresa R.; Fernando, W. G. Dilantha

2012-01-01

376

Herbivore exploits orally secreted bacteria to suppress plant defenses  

PubMed Central

Induced plant defenses in response to herbivore attack are modulated by cross-talk between jasmonic acid (JA)- and salicylic acid (SA)-signaling pathways. Oral secretions from some insect herbivores contain effectors that overcome these antiherbivore defenses. Herbivores possess diverse microbes in their digestive systems and these microbial symbionts can modify plant–insect interactions; however, the specific role of herbivore-associated microbes in manipulating plant defenses remains unclear. Here, we demonstrate that Colorado potato beetle (Leptinotarsa decemlineata) larvae exploit bacteria in their oral secretions to suppress antiherbivore defenses in tomato (Solanum lycopersicum). We found that antibiotic-untreated larvae decreased production of JA and JA-responsive antiherbivore defenses, but increased SA accumulation and SA-responsive gene expression. Beetles benefit from down-regulating plant defenses by exhibiting enhanced larval growth. In SA-deficient plants, suppression was not observed, indicating that suppression of JA-regulated defenses depends on the SA-signaling pathway. Applying bacteria isolated from larval oral secretions to wounded plants confirmed that three microbial symbionts belonging to the genera Stenotrophomonas, Pseudomonas, and Enterobacter are responsible for defense suppression. Additionally, reinoculation of these bacteria to antibiotic-treated larvae restored their ability to suppress defenses. Flagellin isolated from Pseudomonas sp. was associated with defense suppression. Our findings show that the herbivore exploits symbiotic bacteria as a decoy to deceive plants into incorrectly perceiving the threat as microbial. By interfering with the normal perception of herbivory, beetles can evade antiherbivore defenses of its host.

Chung, Seung Ho; Rosa, Cristina; Scully, Erin D.; Peiffer, Michelle; Tooker, John F.; Hoover, Kelli; Luthe, Dawn S.; Felton, Gary W.

2013-01-01

377

Herbivore exploits orally secreted bacteria to suppress plant defenses.  

PubMed

Induced plant defenses in response to herbivore attack are modulated by cross-talk between jasmonic acid (JA)- and salicylic acid (SA)-signaling pathways. Oral secretions from some insect herbivores contain effectors that overcome these antiherbivore defenses. Herbivores possess diverse microbes in their digestive systems and these microbial symbionts can modify plant-insect interactions; however, the specific role of herbivore-associated microbes in manipulating plant defenses remains unclear. Here, we demonstrate that Colorado potato beetle (Leptinotarsa decemlineata) larvae exploit bacteria in their oral secretions to suppress antiherbivore defenses in tomato (Solanum lycopersicum). We found that antibiotic-untreated larvae decreased production of JA and JA-responsive antiherbivore defenses, but increased SA accumulation and SA-responsive gene expression. Beetles benefit from down-regulating plant defenses by exhibiting enhanced larval growth. In SA-deficient plants, suppression was not observed, indicating that suppression of JA-regulated defenses depends on the SA-signaling pathway. Applying bacteria isolated from larval oral secretions to wounded plants confirmed that three microbial symbionts belonging to the genera Stenotrophomonas, Pseudomonas, and Enterobacter are responsible for defense suppression. Additionally, reinoculation of these bacteria to antibiotic-treated larvae restored their ability to suppress defenses. Flagellin isolated from Pseudomonas sp. was associated with defense suppression. Our findings show that the herbivore exploits symbiotic bacteria as a decoy to deceive plants into incorrectly perceiving the threat as microbial. By interfering with the normal perception of herbivory, beetles can evade antiherbivore defenses of its host. PMID:24019469

Chung, Seung Ho; Rosa, Cristina; Scully, Erin D; Peiffer, Michelle; Tooker, John F; Hoover, Kelli; Luthe, Dawn S; Felton, Gary W

2013-09-09

378

Characterization of the pigment xanthomonadin in the bacterial genus Xanthomonas using micro- and resonance Raman spectroscopy  

NASA Astrophysics Data System (ADS)

We used micro- and resonance Raman spectroscopy with 785 nm and 514.5 nm laser excitation, respectively, to characterize a plant pathogenic bacteria, Xanthomonas axonopodis pv. dieffenbachiae D150. The bacterial genus Xathomonas is closely related to bacterial genus Stenotrophomonas that causes an infection in humans. This study has identified for the first time the unique Raman spectra of the carotenoid-like pigment xanthomonadin of the Xanthomonas strain. Xanthomonadin is a brominated aryl-polyene pigment molecule similar to carotenoids. Further studies were conducted using resonance Raman spectroscopy with 514.5 nm laser excitation on several strains of the bacterial genus Xanthomonas isolated from numerous plants from various geographical locations. The current study revealed that the Raman bands representing the vibrations (v1, v2, v3) of the polyene chain of xanthomonadin are 1003-1005 (v3), 1135-1138 (v2), and 1530 (v1). Overtone bands representing xanthomonadin were identified as 2264-2275 (2v2), and combinational bands at 2653-2662 (v1+ v2). The findings from this study validate our previous finding that the Raman fingerprints of xanthomonadin are unique for the genus Xanthomonas. This facilitates rapid identification (~5 minutes) of Xanthomonas spp. from bacterial culture plates. The xanthomonadin marker is different from Raman markers of many other bacterial genus including Agrobacterium, Bacillus, Clavibacter, Enterobacter, Erwinia, Microbacterium, Paenibacillus, and Ralstonia. This study also identified Xanthomonas spp. from bacterial strains isolated from a diseased wheat sample on a culture plate.

Paret, Mathews L.; Sharma, Shiv K.; Misra, Anupam K.; Acosta, Tayro; deSilva, Asoka S.; Vowell, Tomie; Alvarez, Anne M.

2012-05-01

379

Complex sputum microbial composition in patients with pulmonary tuberculosis  

PubMed Central

Background An increasing number of studies have implicated the microbiome in certain diseases, especially chronic diseases. In this study, the bacterial communities in the sputum of pulmonary tuberculosis patients were explored. Total DNA was extracted from sputum samples from 31 pulmonary tuberculosis patients and respiratory secretions of 24 healthy participants. The 16S rRNA V3 hyper-variable regions were amplified using bar-coded primers and pyro-sequenced using Roche 454 FLX. Results The results showed that the microbiota in the sputum of pulmonary tuberculosis patients were more diverse than those of healthy participants (p<0.05). The sequences were classified into 24 phyla, all of which were found in pulmonary tuberculosis patients and 17 of which were found in healthy participants. Furthermore, many foreign bacteria, such as Stenotrophomonas, Cupriavidus, Pseudomonas, Thermus, Sphingomonas, Methylobacterium, Diaphorobacter, Comamonas, and Mobilicoccus, were unique to pulmonary tuberculosis patients. Conclusions This study concluded that the microbial composition of the respiratory tract of pulmonary tuberculosis patients is more complicated than that of healthy participants, and many foreign bacteria were found in the sputum of pulmonary tuberculosis patients. The roles of these foreign bacteria in the onset or development of pulmonary tuberculosis shoud be considered by clinicians.

2012-01-01

380

Microbial populations of an upflow anaerobic sludge blanket reactor treating wastewater from a gelatin industry.  

PubMed

The microbial populations of an upflow anaerobic sludge blanket reactor, used for treating wastewater from the gelatin industry, were studied by microbiological methods and phase-contrast and electron microscopy. Microscopy examination of the sludge showed a complex mixture of various rod-shaped and coccoid bacterial pluslong filaments and verymobile curved rods. In addition free-living anaerobic ciliates and flagellates were also observed. The trophic group population observed in decreasing order of dominance were hydrolytic and acetogenic at 10(6) and sulfate reducing and methanogenic at 10(5). The rate of methane production in anaerobic granular sludge cultivated in growth medium supplement with formate pressurized with H2:CO2 showed a significant increase in methane yield compared with theseed culture containingthe same substrate and atmosphere of N2:CO2. Similar rates of methane production were observed when the growth medium was supplemented with acetate pressurized either with H2:CO2 or N2:CO2. The number of total anaerobic bacteria at 10(7), fecal coliforms and total coliforms at 10(6), and fecal streptococci at 10(3) is based on colony counts on solid media. The four prevalent species of facultative anaerobic gram-negative bacteria that belong to the family of Enterobacteriaceae were identified as Escherichia coli, Esherichia fergusonii, Klebsiella oxytoca, and Citrobacter freundii. The species Aeromonas hydrophila, Aeromonas veronii, Acinetobacter iwoffi and Stenotrophomonas maltophila were the most frequently isolated glucose fermenting and nonfermenting gram-negative bacilli. PMID:11873883

Vieira, A M; Bergamasco, R; Gimenes, M L; Nakamura, C V; Dias Filho, B P

2001-12-01

381

Plant-microbe interactions promoting plant growth and health: perspectives for controlled use of microorganisms in agriculture.  

PubMed

Plant-associated microorganisms fulfill important functions for plant growth and health. Direct plant growth promotion by microbes is based on improved nutrient acquisition and hormonal stimulation. Diverse mechanisms are involved in the suppression of plant pathogens, which is often indirectly connected with plant growth. Whereas members of the bacterial genera Azospirillum and Rhizobium are well-studied examples for plant growth promotion, Bacillus, Pseudomonas, Serratia, Stenotrophomonas, and Streptomyces and the fungal genera Ampelomyces, Coniothyrium, and Trichoderma are model organisms to demonstrate influence on plant health. Based on these beneficial plant-microbe interactions, it is possible to develop microbial inoculants for use in agricultural biotechnology. Dependent on their mode of action and effects, these products can be used as biofertilizers, plant strengtheners, phytostimulators, and biopesticides. There is a strong growing market for microbial inoculants worldwide with an annual growth rate of approximately 10%. The use of genomic technologies leads to products with more predictable and consistent effects. The future success of the biological control industry will benefit from interdisciplinary research, e.g., on mass production, formulation, interactions, and signaling with the environment, as well as on innovative business management, product marketing, and education. Altogether, the use of microorganisms and the exploitation of beneficial plant-microbe interactions offer promising and environmentally friendly strategies for conventional and organic agriculture worldwide. PMID:19568745

Berg, Gabriele

2009-07-01

382

Genetic basis of long-chain aliphatic hydrocarbon biosynthesis in bacteria. Final technical report, July 7, 1981-January 6, 1983  

SciTech Connect

A variety of Micrococcus species, some related Arthrobacter, and Pseudomonas maltophilia are among the few bacteria which produce significant quantities of long chain aliphatic hydrocarbons. It was the purpose of this investigation to initiate studies aimed at understanding the genetic basis of aliphatic hydrocarbon production. Results have shown that some strains of several of the Micrococcus species carry plasmids, but they appear not to be associated with hydrocarbon production. Clearly, plasmids are not required for hydrocarbon biosynthesis, as many plasmidless strains produce large quantities of hydrocarbons with normal species-specific profiles. This is the first report on the occurrence of plasmids in Micrococcus species such as M. roseus, M. varians, M. kristinae, M. agilis, M. nishinomiyaensis, and unnamed, nonhuman primate Micrococcus spp. It is also the first report on aliphatic hydrocarbon production in M. agilis and the above nonhuman primate species. Although hydrocarbon production is not specifically under plasmid control, micrococcal plasmids may be able to serve as vectors for cloned hydrocarbon biosynthesis genes and ultimately used in the genetic engineering of this important group of organisms. For this reason, we initiated studies on the nucleotide sequence relationships, restriction enzyme digestion, and marking of several of the more interesting plasmids. Results have indicated that within species some plasmids share considerable nucleotide sequence homology. It is recommended that future investigations on these organisms should focus on unraveling the hydrocarbon biosynthetic pathway(s), isolating and characterizing the various enzymes involved with hydrocarbon biosynthesis, isolating and cloning the various chromosomal genes controlling these enzymes, and exploring genetic transfer (exchange) systems. Expression of micrococcal hydrocarbon genes in other organisms should also be evaluated.

Kloos, W.E.

1983-01-01

383

Recovery of bacteria from reprocessed high flux dialyzers after bacterial contamination of the header spaces and O-rings.  

PubMed

The Centers for Disease Control (CDC) have received reports of bacteremia in patients on high flux dialysis attributed to contamination of dialyzer header spaces or o-rings. A study was performed in which header spaces and o-rings of Hemoflow F-80 dialyzers (Fresenius AG, Bad Homburg, FRG) were exposed to an aqueous suspension of Xanthomonas maltophilia and Mycobacterium chelonae for 1 hour. After exposure, the dialyzers were reprocessed manually with 4% formaldehyde, 4% Renalin, 2.5% Renalin, or sterile water (SW) as a control, or with an automated reprocessing machine using 3.25% Renalin. After 48 hours the blood compartment (BC) was drained and rinsed twice with 500 ml of SW. Each BC sample was cultured. To simulate dialysis, separate circulates of SW were pumped through the DC and the BC. After 15 minutes, the BC circulate was cultured, headers were unscrewed, and o-rings, header caps, and fiber bundle ends were cultured. For each germicide, bacteria were recovered in low numbers, primarily from the o-rings and the o-ring groove in the header caps. In 38 tests, a total of 60 of 342 assays (17.5%) were positive. In only one of these tests one bacterial colony forming unit (cfu) was recovered from the BC circulate during simulated dialysis. It was concluded that if header spaces and o-rings are contaminated, bacteria could be sealed protectively from the germicide. However, concentrations of surviving bacteria were low, probably outside the BC, and did not effectively contaminate the BC circulate during simulated dialysis. PMID:2688713

Bland, L A; Arduino, M J; Aguero, S M; Favero, M S

384

Evaluation of the four-hour Micro-ID technique for direct identification of oxidase-negative, Gram-negative rods from blood cultures.  

PubMed

A 4-h Micro-ID technique for direct identification of oxidase-negative gram-negative rods from positive blood cultures was compared to subculture and species identification of single colonies by API 20E and Micro-ID, using standardized inocula. A total of 127 patients (220 positive cultures) were studied. Isolates included 96 Escherichia coli, 46 Klebsiella pneumoniae, 7 Klebsiella oxytoca, 8 Enterobacter aerogenes, 17 Enterobacter cloacae, 19 Serratia marcescens, 2 Serratia liquefaciens, 8 Proteus mirabilis, 1 Salmonella species, 1 Morganella morganii, 6 Haemophilus influenzae, 2 Haemophilus parainfluenzae, 3 Bacteroides fragilis, 3 Acinetobacter calcoaceticus biotype anitratus, and 1 Pseudomonas maltophilia. In 90% of the cultures, identification by Micro-ID was identical to that obtained after subculture; if the 15 non-enterobacterial isolates were excluded, the corresponding figure was 96.6%. Enterobacteria identified incorrectly by direct Micro-ID were three S. marcescens (two identified as S. liquefaciens, one as Hafnia alvei), two S. liquefaciens (both identified as E. cloacae), and two K. pneumoniae (one identified as Klebsiella ozaenae, the other as Serratia rubidaea). None of the 15 non-enterobacterial cultures were correctly identified by Micro-ID (non-identifiable, or classified as Providencia/Yersinia/Klebsiella species). Although biochemical discrepancies between direct and final Micro-ID tests occurred in 41% of the enterobacterial cultures, this did not seriously interfere with identification. Direct species identification of Enterobacteriaceae from blood cultures by direct Micro-ID is accurate and easily performed and identified organisms within 4 h compared to at least 24 h by most other methods; the direct Micro-ID technique would be rendered even more valuable by the additional capability of identifying non-enterobacterial gram-negative isolates. PMID:6999020

Appelbaum, P C; Schick, S F; Kellogg, J A

1980-10-01

385

Further studies on thymidine kinase: distribution pattern of the enzyme in bacteria.  

PubMed

Various micro-organisms (131 strains of 73 species) were studied for their ability to produce thymidine kinase (TK; EC 2.7.1.21). Taking the specific TK activity of Escherichia coli K12 [specific activity of sonicated cell extracts 95-194 pmol min-1 (mg protein)-1] as 100%, the test organisms had the following relative specific TK activities. In the Gram-positive cocci, Staphylococcus aureus (21-84%) showed higher activity than Staph. epidermidis (1-20%) and Streptococcus (1-7%) except for one strain of Strep. pyogenes (29%). Neisseria sicca, a Gram-negative coccus, lacked TK. Gram-positive endospore-forming rods showed significant activity (Bacillus, 13-51%; Clostridium perfringens, 9-18%) except for one strain of B. megaterium (2%) and C. difficile (1-3%). Among the Gram-positive asporogenous rods, Listeria monocytogenes and six species of Lactobacillus (especially L. brevis, L. buchneri and L. casei) had moderate to high activity (23-348%) but L. acidophilus, L. bulgaricus, L. lactis and L. cellobiosus had low activity (0-8%). Of the species of Pseudomonas studied, most lacked TK but Ps. fluorescens and Ps. maltophilia had significant TK activity (15-53%). Of the Gram-negative facultative anaerobes, Vibrio lacked TK, while Enterobacteriaceae, including Salmonella (148-1120%), Escherichia (59-141%), Klebsiella (78-299%) and Serratia (61-110%), had a high activity. Proteus had a somewhat lower activity (0-34%) except for 'Pr. rettgerella' (307%). Propionibacterium and Bifidobacterium and related organisms other than Streptomyces, Nocardia, Rhodococcus, Corynebacterium and Mycobacterium lacked TK. The seven species of Candida tested, and Cryptococcus neoformans, essentially lacked TK.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:4093763

Saito, H; Tomioka, H; Ohkido, S

1985-11-01

386

In vitro evaluation of GR69153, a novel catechol-substituted cephalosporin.  

PubMed Central

GR69153 is a C-7 catechol cephalosporin with a broad spectrum of activity against members of the family Enterobacteriaceae (MICs for 50% of strains tested [MIC50s], 0.008 to 0.5 micrograms/ml), Staphylococcus aureus (MIC50, 4 micrograms/ml), Pseudomonas aeruginosa (MIC50, 0.25 micrograms/ml), Haemophilus influenzae (MIC50, 0.03 micrograms/ml), Neisseria gonorrhoeae (MIC50, 0.03 micrograms/ml), and Acinetobacter spp. (MIC50, 2 micrograms/ml). Potent GR69153 activity was also demonstrated against Moraxella catarrhalis, pneumococci, beta-hemolytic streptococci, gram-positive anaerobes, and most species of coagulase-negative staphylococci. The activity of GR69153 was generally two- to fourfold greater than that of ceftazidime. Resistance level GR69153 MICs for 90% of strains tested (greater than or equal to 32 micrograms/ml) were found most often among Citrobacter freundii, Enterobacter spp. and Morganella morganii strains. GR69153 did not significantly inhibit enterococci, Xanthomonas maltophilia, the Bacteroides fragilis group, Corynebacterium jeikeium, or Listeria monocytogenes. GR69153 was bactericidal and was generally beta-lactamase stable, and MICs were only slightly increased by high inoculum concentrations. Activity was enhanced in an iron-deficient medium, and a modest MIC difference attributed to iron availability was noted between standard agar and broth test results. GR69153 was confirmed to be a potent, catechol-substituted cephalosporin with a spectrum slightly wider than that of ceftazidime, but it was less active than cefpirome or imipenem against some gram-positive pathogens and anaerobes.

Erwin, M E; Jones, R N; Barrett, M S; Briggs, B M; Johnson, D M

1991-01-01

387

Tertiary structure-related activity of tick defensin (persulcatusin) in the taiga tick, Ixodes persulcatus.  

PubMed

Defensins are small cysteine-rich cationic proteins found in both vertebrates and invertebrates constituting the front line of host innate immunity. To examine the importance of the tertiary structure of tick defensin in its antimicrobial activity, we synthesized two types of the peptides with tertiary structure or primary one on basis of the information of the sequence in the defensin originated from the taiga tick, Ixodes persulcatus. Chemically synthesized peptides were used to investigate the activity spectrum against Staphylococcus aureus, Borrelia garinii and flora-associated bacteria. Both synthetic peptides showed antimicrobial activity against S. aureus in short-time killing within 1 h, but they do not show the activity against B. garinii, Stenotrophomonas maltophila and Bacillus spp., which were frequently isolated from the midgut of I. persulcatus. The teriary structure brought more potent activity to S. aureus than primary one in short-time killing. We also examined its antimicrobial activity by evaluation of growth inhibition in the presence of the synthetic peptides. Minimum inhibitory concentration (MIC) was ranged from 1.2 to 5.0 ?g/ml in tertiary peptide and from 10 to 40 ?g/ml in primary peptide, when 10 strains of S. aureus were used. From the curve of cumulative inhibition rates, MIC50 (MIC which half of the strains showed) to S. aureus is about 1.2 ?g/ml in the peptide with tertiary structure and about 10 ?g/ml in the linear one. Corynebacterium renale is 10 times or more sensitive to tertiary peptide than primary one. In conclusion, the presence of 3 disulfide bridges, which stabilize the molecule and maintain the tertiary structure, is considered to have an effect on their antimicrobial activities against Gram-positive bacteria such as S. aureus. PMID:20596886

Isogai, Emiko; Isogai, Hiroshi; Okumura, Kazuhiko; Hori, Hatsuhiro; Tsuruta, Hiroki; Kurebayashi, Yoichi

2010-07-02

388

Survey of bacterial diversity in chronic wounds using Pyrosequencing, DGGE, and full ribosome shotgun sequencing  

PubMed Central

Background Chronic wound pathogenic biofilms are host-pathogen environments that colonize and exist as a cohabitation of many bacterial species. These bacterial populations cooperate to promote their own survival and the chronic nature of the infection. Few studies have performed extensive surveys of the bacterial populations that occur within different types of chronic wound biofilms. The use of 3 separate16S-based molecular amplifications followed by pyrosequencing, shotgun Sanger sequencing, and denaturing gradient gel electrophoresis were utilized to survey the major populations of bacteria that occur in the pathogenic biofilms of three types of chronic wound types: diabetic foot ulcers (D), venous leg ulcers (V), and pressure ulcers (P). Results There are specific major populations of bacteria that were evident in the biofilms of all chronic wound types, including Staphylococcus, Pseudomonas, Peptoniphilus, Enterobacter, Stenotrophomonas, Finegoldia, and Serratia spp. Each of the wound types reveals marked differences in bacterial populations, such as pressure ulcers in which 62% of the populations were identified as obligate anaerobes. There were also populations of bacteria that were identified but not recognized as wound pathogens, such as Abiotrophia para-adiacens and Rhodopseudomonas spp. Results of molecular analyses were also compared to those obtained using traditional culture-based diagnostics. Only in one wound type did culture methods correctly identify the primary bacterial population indicating the need for improved diagnostic methods. Conclusion If clinicians can gain a better understanding of the wound's microbiota, it will give them a greater understanding of the wound's ecology and will allow them to better manage healing of the wound improving the prognosis of patients. This research highlights the necessity to begin evaluating, studying, and treating chronic wound pathogenic biofilms as multi-species entities in order to improve the outcomes of patients. This survey will also foster the pioneering and development of new molecular diagnostic tools, which can be used to identify the community compositions of chronic wound pathogenic biofilms and other medical biofilm infections.

Dowd, Scot E; Sun, Yan; Secor, Patrick R; Rhoads, Daniel D; Wolcott, Benjamin M; James, Garth A; Wolcott, Randall D

2008-01-01

389

Study on diversity of endophytic bacterial communities in seeds of hybrid maize and their parental lines.  

PubMed

The seeds of plants are carriers of a variety of beneficial bacteria and pathogens. Using the non-culture methods of building 16S rDNA libraries, we investigated the endophytic bacterial communities of seeds of four hybrid maize offspring and their respective parents. The results of this study show that the hybrid offspring Yuyu 23, Zhengdan958, Jingdan 28 and Jingyu 11 had 3, 33, 38 and 2 OTUs of bacteria, respectively. The parents Ye 478, Chang 7-2, Zheng 58, Jing 24 and Jing 89 had 12, 36, 6, 12 and 2 OTUs, respectively. In the hybrid Yuyu 23, the dominant bacterium Pantoea (73.38 %) was detected in its female parent Ye 478, and the second dominant bacterium of Sphingomonas (26.62 %) was detected in both its female (Ye 478) and male (Chang 7-2) parent. In the hybrid Zhengdan 958, the first dominant bacterium Stenotrophomonas (41.67 %) was detected in both the female (Zheng 58) and male (Chang 7-2) parent. The second dominant bacterium Acinetobacter (9.26 %) was also the second dominant bacterium of its male parent. In the hybrid Jingdan 28, the second dominant bacterium Pseudomonas (12.78 %) was also the second dominant bacterium of its female parent, and its third dominant bacterium Sphingomonas (9.90 %) was the second dominant bacterium of its male parent and detected in its female parent. In the hybrid Jingyu 11, the first dominant bacterium Leclercia (73.85 %) was the third dominant bacterium of its male parent, and the second dominant bacterium Enterobacter (26.15 %) was detected in its male parent. As far as we know, this was the first research reported in China on the diversity of the endophytic bacterial communities of the seeds of various maize hybrids with different genotypes. PMID:22892578

Liu, Yang; Zuo, Shan; Xu, Liwen; Zou, Yuanyuan; Song, Wei

2012-08-15

390

Isolation and functional analysis of denitrifiers in an aquifer with high potential for denitrification.  

PubMed

Aquifers are among the main freshwater sources. The Raigón aquifer is susceptible to contamination, mainly by nitrate and pesticides, such as atrazine, due to increasing agricultural activities in the area. The capacity of indigenous bacteria to attenuate nitrate contamination in different wells of this aquifer was assessed by measuring denitrification rates with either acetate plus succinate or nitrate amendments. Denitrification activity in nitrate-amended assays was significantly higher than in unamended assays, particularly in groundwater from wells where nitrate concentration was 33.5mgL(-1) or lower. Furthermore, groundwater denitrifiers capable of using acetate or succinate as electron donors were isolated, identified by 16S rRNA gene sequencing and evaluated for functional denitrification genes (nirS, nirK and nosZ). Phylogenetic affiliation of 54 isolates showed that all members belonged to nine different genera within the Proteobacteria (Bosea, Ochrobactrum, Azospira, Zoogloea, Acidovorax, Achromobacter, Vogesella, Stenotrophomonas and Pseudomonas). In addition, isolate AR28 that clustered separately from validly described species could potentially belong to a new genus. The majority of the isolates were related to species belonging to previously reported denitrifying genera. However, the phylogeny of the nirS and nosZ genes revealed new sequences of these functional genes. To our knowledge, this is the first isolation and sequencing of the nirS gene from the genus Vogesella, as well as the nosZ gene from the genera Acidovorax and Zoogloea. The results indicated that indigenous bacteria in the Raigón aquifer had the capacity to overcome high nitrate contamination and exhibited functional gene diversity. PMID:23972399

Bellini, M Inés; Gutiérrez, Lucía; Tarlera, Silvana; Scavino, Ana Fernández

2013-08-21

391

Isolation and characterization of endophytic bacteria isolated from the leaves of the common bean (Phaseolus vulgaris).  

PubMed

The common bean is one of the most important legumes in the human diet, but little is known about the endophytic bacteria associated with the leaves of this plant. The objective of this study was to characterize the culturable endophytic bacteria of common bean (Phaseolus vulgaris) leaves from three different cultivars (Vermelhinho, Talismã, and Ouro Negro) grown under the same field conditions. The density of endophytic popula