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1.
Identification and Initial Characterization of Elastase Activity Associated with Vibrio cholerae 总被引:3,自引:0,他引:3
Strains of Vibrio cholerae O1 (Ogawa, Inaba) and non-O1 serogroups have been found to produce an elastolytic protease that can be detected on 0.3% elastin
agar plates or in broth cultures. The elastase enzyme appears to be maximally expressed in late log phase (14–18 h postinoculation)
and has optimum activity at a pH range between 7 and 8. Comparative studies indicate that more than 60% of V. cholerae strains analyzed quantitatively produce more elastase in broth (two- to fourfold higher) than other elastase-positive Vibrio species such as Vibrio vulnificus. The V. cholerae elastase enzyme was not inhibited by trypsin, serine-protease, or thiol-protease inhibitors, but was inhibited by phosphoramidon.
Ultrafiltration studies indicate the V. cholerae elastase enzyme has a molecular weight >30,000, and a 34K protein with possible elastase activity has been detected by SDS-PAGE
for one non-O1 isolate (strain 2396). Cumulative results suggest that the V. cholerae elastase is probably a member of the N-type metalloprotease family and shares similar properties with other elastase enzymes
described for pathogenic and nonpathogenic species in this genus.
Received: 26 February 1999 / Accepted: 29 March 1999 相似文献
2.
Kirschner AK Schauer S Steinberger B Wilhartitz I Grim CJ Huq A Colwell RR Herzig A Sommer R 《Microbial ecology》2011,61(3):496-506
Vibrio cholerae is a human pathogen and natural inhabitant of aquatic environments. Serogroups O1/O139 have been associated with epidemic cholera, while non-O1/non-O139 serogroups usually cause human disease
other than classical cholera. V. cholerae non-O1/non-O139 from the Neusiedler See, a large Central European lake, have caused ear and wound infections, including one
case of fatal septicaemia. Recent investigations demonstrated rapid planktonic growth of V. cholerae non-O1/non-O139 and correlation with zooplankton biomass. The aim of this study was to elucidate the interaction of autochthonous
V. cholerae with two dominant crustacean zooplankton species in the lake and investigate the influence of the natural bacterial community
on this interaction. An existing data set was evaluated for statistical relationships between zooplankton species and V. cholerae and co-culture experiments were performed in the laboratory. A new fluorescence in situ hybridisation protocol was applied
for quantification of V. cholerae non-O1/non-O139 cells, which significantly reduced analysis time. The experiments clearly demonstrated a significant relationship
of autochthonous V. cholerae non-O1/non-O139 with cladocerans by promoting growth of V. cholerae non-O1/non-O139 in the water and on the surfaces of the cladocerans. In contrast, copepods had a negative effect on the growth
of V. cholerae non-O1/non-O139 via competing bacteria from their surfaces. Thus, beside other known factors, biofilm formation by V. cholerae on crustacean zooplankton appears to be zooplankton taxon specific and may be controlled by the natural bacterial community. 相似文献
3.
The aim of this study was to identify novel biofilm inhibitors from actinomycetes isolated from the Arctic against Vibrio cholerae, the causative agent of cholera. The biofilm inhibitory activity of actinomycetes was assessed using biofilm assay and was
confirmed using air–liquid interphase coverslip assay. The potential isolates were identified using 16S rRNA gene sequencing.
Of all, three isolates showed significant biofilm inhibition against V. cholerae. The results showed that 20% of the actinomycetes culture supernatant could inhibit up to 80% of the biofilm formation. When
different extracted fractions were assessed, significant biofilm inhibition activity was only seen in the diethyl ether fraction
of A745. At 200 μg ml−1 of diethyl ether fraction, 60% inhibition of V. cholerae biofilm was observed. The two potential isolates were found to be Streptomyces sp. and one isolate belonged to Nocardiopsis sp. This is the first report showing a Streptomyces sp. and Nocardiopsis sp. isolated from the Arctic having a biofilm inhibitory activity against V. cholerae. The spread of drug resistant V. cholerae strains is a major clinical problem and the ineffectiveness in antibiotic treatment necessitates finding new modes of prevention
and containment of the disease, cholera. The formation of biofilms during the proliferation of V. cholerae is linked to its pathogenesis. Hence, the bioactive compound from the culture supernatant of the isolates identified in this
study may be a promising source for the development of a potential quorum sensing inhibitors against V. cholerae. 相似文献
4.
Rkia Eddabra Wardi Moussaoui Gilles Prévost François Delalande Alain Van Dorsselaer Olivier Meunier Jean-Michel Scheftel Rachida Mimouni 《World journal of microbiology & biotechnology》2011,27(5):1099-1108
A total of 21 isolates of Vibrio
cholerae non-O1 strains were isolated from three wastewater treatment plants in Agadir, Morocco. The isolates were analyzed by biochemical
analysis, antibiogram, pulsed-field gel electrophoresis and the MALDI-TOF patterns of their protein masses were compared.
Over 67% of isolates were susceptible to antimicrobial agents tested and 14% proved resistant to both trimethoprim-sulfamethoxazole
and nalidixic acid. Typing by pulsed-field gel electrophoresis with NotI digestion revealed that the V. cholerae non-O1 strains from Agadir (Morocco) have a lower level of genetic homogeneity, the restriction patterns of whole-chromosomal
DNA grouped the V. cholerae O1 and V. alginolyticus strains into a separate cluster from V. metschnikovii and V. cholerae non-O1 isolates. Furthermore, to gain additional analytical accuracy and reliability in the analysis we used dendrogram based
on MALDI-TOF spectral patterns generated by the BioTyper 1.1™ software. All m/z signatures of all strains tested indicate that the mass spectral data contained sufficient information to distinguish between
strains of V. cholerae. 相似文献
5.
Vibrio cholerae, the etiologic agent of cholera, is autochthonous to various aquatic environments. Recently, it was found that chironomid
(nonbiting midges) egg masses serve as a reservoir for the cholera bacterium and that flying chironomid adults are possible
windborne carriers of V. cholerae non-O1 non-O139. Chironomids are the most widely distributed insect in freshwater. Females deposit egg masses at the water's
edge, and each egg mass contains eggs embedded in a gelatinous matrix. Hemagglutinin/protease, an extracellular enzyme of
V. cholerae, was found to degrade chironomid egg masses and to prevent them from hatching. In a yearly survey, chironomid populations
and the V. cholerae in their egg masses followed phenological succession and interaction of host–pathogen population dynamics. In this report,
it is shown via FISH technique that most of the V. cholerae inhabiting the egg mass are in the viable but nonculturable (VBNC) state. The diversity of culturable bacteria from chironomid
egg masses collected from two freshwater habitats was determined. In addition to V. cholerae, representatives of the following genera were isolated: Acinetobacter, Aeromonas, Klebsiella, Shewanella, Pseudomonas, Paracoccus, Exiguobacterium, and unidentified bacteria. Three important human pathogens, Aeromonas
veronii, A. caviae, and A. hydrophila, were isolated from chironomid egg masses, indicating that chironomid egg masses may be a natural reservoir for pathogenic
Aeromonas species in addition to V. cholerae. All isolates of V. cholerae were capable of degrading chironomid egg masses. This may help explain their host–pathogen relationship with chironomids.
In contrast, almost none of the other bacteria that were isolated from the egg masses possessed this ability. Studying the
interaction between chironomid egg masses, the bacteria inhabiting them, and V. cholerae could contribute to our understanding of the nature of the V. cholerae–egg mass interactions. 相似文献
6.
Natsumi Okada Shigeaki Matsuda Junko Matsuyama Kwon-Sam Park Calvin de los Reyes Kazuhiro Kogure Takeshi Honda Tetsuya Iida 《BMC microbiology》2010,10(1):302
Background
Vibrios, which include more than 100 species, are ubiquitous in marine and estuarine environments, and several of them e.g. Vibrio cholerae, V. parahaemolyticus, V. vulnificus and V. mimicus, are pathogens for humans. Pathogenic V. parahaemolyticus strains possess two sets of genes for type III secretion system (T3SS), T3SS1 and T3SS2. The latter are critical for virulence of the organism and be classified into two distinct phylogroups, T3SS2α and T3SS2β, which are reportedly also found in pathogenic V. cholerae non-O1/non-O139 serogroup strains. However, whether T3SS2-related genes are present in other Vibrio species remains unclear. 相似文献7.
The capability for biofilm and quorum-sensing (QS) signaling production among Pseudomonas aeruginosa isolates were evaluated. A total of 231 isolates were recovered from sputa of cystic fibrosis (CF, n = 104) and non-CF (non-CF, n = 127) patients. One hundred ninety-seven (85.3%; 95% CI 80.1–89.3%) were biofilm producers and 157 (68%; 95% CI 61.7–73.6%)
were weak QS-producing. No difference was observed between CF and non-CF isolates regarding the ability to produce biofilm
and QS-signaling. Interestingly, the degree of QS production appears to be related to the degree of biofilm production. Thus,
blocking QS pathways may be crucial in the prevention and treatment of biofilm-related infections. 相似文献
8.
Antipathogenic therapy is an outcome of the quorum-sensing inhibition (QSI) mechanism, which targets autoinducer-dependent
virulent gene expression in bacterial pathogens. N-acyl homoserine lactone (AHL) acts as a key regulator in the production of virulence factors and biofilm formation in Pseudomonas aeruginosa PAO1 and violacein pigment production in Chromobacterium violaceum. In the present study, the marine bacterial strain SS4 showed potential QSI activity in a concentration-dependent manner
(0.5–2 mg/ml) against the AHL-mediated violacein production in C. violaceum (33–86%) and biofilm formation (33–88%), total protease (20–65%), LasA protease (59–68%), LasB elastase (36–68%), pyocyanin
(17–86%) and pyoverdin productions in PAO1. The light and confocal laser scanning microscopic analyses confirmed the reduction
of the biofilm-forming ability of PAO1 when treated with SS4 extract. Furthermore, the antibiofilm potential was confirmed
through static biofilm ring assay, in which ethyl acetate extract of SS4 showed concentration-dependent reduction in the biofilm-forming
ability of PAO1. Thus, the result of this study clearly reveals the antipathogenic and antibiofilm properties of the bacterial
isolate SS4. Through 16S rDNA analysis, the strain SS4 was identified as Bacillus sp. (GenBank Accession Number: GU471751). 相似文献
9.
Yu. A. Nikolaev I. A. Borzenkov A. L. Tarasov N. G. Loiko A. N. Kozlova V. F. Gal’chenko G. I. El’-Registan 《Microbiology》2010,79(6):747-752
The adaptogenic effect of the chemical analogues of alkylhydroxybenzenes (AHBs), bacterial extracellular autoregulators (the
individual compound C7-AHB and its technical preparation Sidovit), was demonstrated for two pseudomonad species, Pseudomonas aeruginosa and P. fluorescens. The protective effect of AHBs resulted in increased growth rate and biomass accumulation in bacteria grown under suboptimal
conditions within the species tolerance range. The adaptogenic effect of AHBs (10–50 μmg/l) was more pronounced under more
unfavorable growth conditions. In the case of P. fluorescens, the individual compound C7-AHB increased the biomass yield by 30% under alkaline conditions (pH 9.5), when the growth rate
decreased by 80–90% compared to the optimum (pH 5.5–7.5). The Sidovit preparation, containing a mixture of natural AHBs with
C7-AHB as the main component, increased the growth rate of P. aeruginosa by 40–60% at nonoptimal temperatures (45 and 10°C) or under enhanced salinity (1% NaCl). The action of AHBs as regulators
of the rpoS and SOS response stress regulons was demonstrated to be among the mechanisms of their adaptogenic effect, as was demonstrated
with the relevant reporter genes in the model strains E. coli C600 thi, thr, leuΔ(pro-lac) with the osmE-lacZ and umuD-lacZ hybrid operons, respectively. AHBs are technologically and economically acceptable as adaptogenic supplements for bacterial
preparations used in soil bioremediation and oil spillage removal under conditions unfavorable for microbial growth, including
increased salinity, extreme pH, and fluctuating sub- or supraoptimal temperatures. 相似文献
10.
11.
Naomi Higa Yasuko Honma M. John Albert Masaaki Iwanaga 《Microbiology and immunology》1993,37(12):971-974
Vibrio cholerae O139 (synonym Bengal), a novel serovar of V. cholerae, is the causative agent of large outbreaks of cholera-like illness currently sweeping India and Bangladesh. Eight randomly selected V. cholerae O139 isolates were studied for their biological properties, which were compared with those of V. cholerae O1 and other V. cholerae non-O1. The V. cholerae O139 isolates were characterized by the production of large amount of cholera toxin, hemagglutination, weak hemolytic properties, resistance to polymyxin B, lysogeny with, and production of, kappa type phage (4/8 isolates only), and resistance to both classical and El Tor-specific phages. Thus, V. cholerae O139 isolates had an overall similarity with V. cholerae O1 El Tor. 相似文献
12.
Christophe Sandt Truis Smith-Palmer Jonathan Comeau David Pink 《Applied microbiology and biotechnology》2009,83(6):1171-1182
The Raman spectra, water content, and biomass density of wild-type (WT) Pseudomonas aeruginosa PAO1, small colony variant (SCV) PAO1, and Pseudoalteromonas sp. NCIMB 2021 biofilms were compared in order to determine their variation with strain and species. Living, fully submerged
biofilms were analyzed in situ by confocal Raman microspectroscopy for up to 2 weeks. Water to biomass ratios (W/BRs), which
are the ratios of the O–H stretching vibration of water at 3,450 cm−1 to the C–H stretching band characteristic of biomass at 2,950 cm−1, were used to estimate the biomass density and cell density by comparison with W/BRs of protein solutions and bacterial suspensions,
respectively, on calibration curves. The hydration within SCV biofilm colonies was extremely heterogeneous whereas W/BRs were
generally constant in young WT biofilm colonies. The mean biomass in biofilm colonies of WT or colony cores of SCV was typically
equivalent to 16% to 27% protein (w/v), but was 10% or less for NCIMB 2021. The corresponding cell densities were 7.5 to >10 × 1010 cfu mL−1 for SCV, while the maximum cell density for NCIMB biofilms was 2.8 × 1010 cfu mL−1. 相似文献
13.
Sandra Fernanda Bilbao Orozco Beatriz Vahan Kilikian 《World journal of microbiology & biotechnology》2008,24(2):263-268
The production of red pigments and citrinin by Monascus purpureus CCT3802 was investigated in submerged batch cultures performed in two phases: in the first phase, cells were grown on glucose,
at pH 4.5, 5.5 or 6.5; after glucose depletion, pH was adjusted, when necessary, to 4.5, 5.5, 6.5, 7.0, 8.0 or 8.5, for a
production phase. The highest total red pigments absorbance of 11.3 U was 16 times greater than the lowest absorbance and
was achieved with growth at pH 5.5, followed by production at pH 8.5, which causes an immediate reduction of the intra cellular
red pigments from 75% to 17% of the total absorbance. The lowest citrinin concentration, 5.5 mg L−1, was verified in the same culture while the highest concentration, 55 mg L−1, was verified in cultures entirely carried out at pH 5.5. An alkaline medium, besides promoting intra cellular red pigments
excretion, strongly represses citrinin synthesis. 相似文献
14.
Christopher J. Grim Elisa Taviani Munirul Alam Anwar Huq R. Bradley Sack Rita R. Colwell 《Applied microbiology》2008,74(3):708-715
Several species of the genus Vibrio, including Vibrio cholerae, are bioluminescent or contain bioluminescent strains. Previous studies have reported that only 10% of V. cholerae strains are luminescent. Analysis of 224 isolates of non-O1/non-O139 V. cholerae collected from Chesapeake Bay, MD, revealed that 52% (116/224) were luminescent when an improved assay method was employed and 58% (130/224) of isolates harbored the luxA gene. In contrast, 334 non-O1/non-O139 V. cholerae strains isolated from two rural provinces in Bangladesh yielded only 21 (6.3%) luminescent and 35 (10.5%) luxA+ isolates. An additional 270 clinical and environmental isolates of V. cholerae serogroups O1 and O139 were tested, and none were luminescent or harbored luxA. These results indicate that bioluminescence may be a trait specific for non-O1/non-O139 V. cholerae strains that frequently occur in certain environments. Luminescence expression patterns of V. cholerae were also investigated, and isolates could be grouped based on expression level. Several strains with defective expression of the lux operon, including natural K variants, were identified. 相似文献
15.
Daniela Ceccarelli Arlene Chen Nur A. Hasan Shah M. Rashed Anwar Huq Rita R. Colwell 《Applied and environmental microbiology》2015,81(6):1909-1918
Non-O1/non-O139 Vibrio cholerae inhabits estuarine and coastal waters globally, but its clinical significance has not been sufficiently investigated, despite the fact that it has been associated with septicemia and gastroenteritis. The emergence of virulent non-O1/non-O139 V. cholerae is consistent with the recognition of new pathogenic variants worldwide. Oyster, sediment, and water samples were collected during a vibrio surveillance program carried out from 2009 to 2012 in the Chesapeake Bay, Maryland. V. cholerae O1 was detected by a direct fluorescent-antibody (DFA) assay but was not successfully cultured, whereas 395 isolates of non-O1/non-O139 V. cholerae were confirmed by multiplex PCR and serology. Only a few of the non-O1/non-O139 V. cholerae isolates were resistant to ampicillin and/or penicillin. Most of the isolates were sensitive to all antibiotics tested, and 77 to 90% carried the El Tor variant hemolysin gene hlyAET, the actin cross-linking repeats in toxin gene rtxA, the hemagglutinin protease gene hap, and the type 6 secretion system. About 19 to 21% of the isolates carried the neuraminidase-encoding gene nanH and/or the heat-stable toxin (NAG-ST), and only 5% contained a type 3 secretion system. None of the non-O1/non-O139 V. cholerae isolates contained Vibrio pathogenicity island-associated genes. However, ctxA, ace, or zot was present in nine isolates. Fifty-five different genotypes showed up to 12 virulence factors, independent of the source of isolation, and represent the first report of both antibiotic susceptibility and virulence associated with non-O1/non-O139 V. cholerae from the Chesapeake Bay. Since these results confirm the presence of potentially pathogenic non-O1/non-O139 V. cholerae, monitoring for total V. cholerae, regardless of serotype, should be done within the context of public health. 相似文献
16.
Lupinus albus L. were grown in rhizoboxes containing a soil amended with sparingly available Fe–P or Al–P (100 μg P g−1 soil/resin mixture). Root halves of individual plants were supplied with nutrient solution (minus P) buffered at either pH 5.5
or 7.5, to assess whether the source of mineral-bound P and/or pH influence cluster-root growth and carboxylate exudation.
The P-amended soil was mixed 3:1 (w/w) with anion-exchange resins to allow rapid fixation of carboxylates. Treatments lasted 10 weeks. Forty percent and 30% of
the root mass developed as cluster roots in plants grown on Fe–P and Al–P respectively, but cluster-root growth was the same
on root-halves grown at pH 5.5 or 7.5. Mineral-bound P source (Al– or Fe–P) had no influence on the types of carboxylates
measured in soil associated with cluster roots—citrate (and trace amounts of malate and fumarate) was the only major carboxylate
detected. The [citrate] in the rhizosphere of cluster roots decreased with increased shoot P status (suggesting a systemic
effect) and also, only for plants grown on Al–P, with decreased pH in the root environment (suggesting a local effect). In
a separate experiment using anion exchange resins pre-loaded with malate or citrate, we measured malate (50%) and citrate
(79%) recovery after 30 days in soil. We therefore, also conclude that measurements of [citrate] and [malate] at the root
surface may be underestimated and would be greater than the 40- and 1.6-μmol g−1 root DM, respectively estimated by us and others because of decomposition of carboxylates around roots prior to sampling. 相似文献
17.
ClinicalPseudomonas aeruginosa: Potential factors of pathogenicity and resistance to antimicrobials 总被引:4,自引:4,他引:0
Resistance to 17 antimicrobials, surface hydrophobicity, motility, biofilm, production ofN-acylhomoserine lactone signal molecules (N-butyrylhomoserine lactone andN-3-oxolauroylhomoserine lactone) and response to oxidative stress were analyzed in 47 clinicalPseudomonas aeruginosa strains. In addition to natural resistance, the strains demonstrated the greatest level of resistance to cefotaxime (91.5
%). Isolates in the range of 44.7–57.4 % were resistant to aminoglycosides and ciprofloxacin, of 25.5–36.2 % to cephalosporins.
On the other hand, 97.9 % remained susceptible to meropenem, 93.6 % to piperacillin + tazobactam and 87.2% to piperacillin.
The majority of the strains (72.3 %) manifested their hydrophilic character. Higher zones of motility showed 12 isolates (in
average 54.8 mm) as compared to the others (30.2 mm). Approximately 1/3 of the strains (29.8 %) produced a higher amount of
biofilm quantified by measuring the absorbance of solubilized crystal violet (0.20–0.46) than the rest of isolates (0–0.19).
All but two strains producedN-3-oxolauroylhomoserine lactone and in 48.9 % of samplesN-butyrylhomoserine lactone were detected. Only four isolates with higher biofilm production showed both types of homoserine
lactone. Majority of the strains (70.2 %) manifested higher resistance to H2O2 than the rest of the strains. The group of strains resistant to aminoglycosides and ciprofloxacin revealed a significantly
higher number of hydrophobic strains (compared with the sensitive ones). In contrast, higher number of strains sensitive to
aminoglycosides and ciprofloxacin or only to ciprofloxacin producedN-butyrylhomoserine lactone and biofilm (compared to the resistant ones). Such association was not found among the rest of
the tested parameters. The results indicate that the resistance to antimicrobials inP. aeruginosa isolates was not generally associated with changes in the production of the pathogenicity factors. 相似文献
18.
Isolation of Non-O1 Vibrio cholerae Serovars from Oregon Coastal Environments 总被引:5,自引:4,他引:1 下载免费PDF全文
Water, sediment, and shellfish from three Oregon estuaries were cultured for pathogenic Vibrio species. Non-O1 serovars of V. cholerae were the most common pathogenic Vibrio species recovered. Non-O1 V. cholerae were isolated from all three estuaries sampled, covering an area of about 170 miles along the Oregon coast. Non-O1 V. cholerae were isolated from water and sediment, but not shellfish, at temperatures ranging from 11 to 19°C and salinities of 2.3 to 26‰. Sixteen isolates representing 12 different non-O1 serovars were identified, while four non-O1 V. cholerae isolates failed to react with any of the 54 antisera tested. These results indicate that non-O1 V. cholerae serovars can be found over a large geographic area and under a variety of environmental conditions. These organisms are apparently an autochthonous component of these estuarine microbial communities. 相似文献
19.
A Vibrio cholerae O1 phage-typing scheme, developed in the USSR, has been used to type 120 strains of V. cholerae O1 isolated in Africa and Asia, and 56 non-O1 V. cholerae isolated in England and Wales from infections contracted abroad. 90.9% of V. cholerae O1 were typable. Phage type 13 predominated among African strains whereas types 11 and 15 were more common among strains from Asia. Only 14.3% of non-O1 V. cholerae reacted with the phages. 相似文献
20.
Bita Bakhshi Hajar Mohammadi-Barzelighi Neda Hosseini-Aliabad Mohammad R. Pourshafie 《Annals of microbiology》2014,64(1):49-53
The aim of this study was to investigate the presence of TCP gene clusters among clinical and environmental Vibrio cholerae isolates and to explore the genetic relatedness of isolates using ribotyping technique. A total of 50 V. cholerae strains (30 clinical and 20 environmental) were included in this study. Three clinical isolates were negative for TCP cluster genes while the cluster was absent in all of the environmental strains. Ribotyping of rRNA genes with BglI produced 18 different ribotype patterns, three of which belonged to clinical O1 serotype isolates. The remaining 15 ribotypes belonged to clinical non-O1, non-O139 serogroups (two patterns) and environmental non-O1, non-O139 serogroups (13 patterns). Clinical V. cholerae O1 strains from 2004 through 2006 and several environmental non-O1, non-O139 V. cholerae strains from 2006 showed 67.3 % similarity and fell within one single gene cluster. Ribotyping analysis made it possible to further comprehend the close originality of clinical isolates as very little changes have been occurred within rRNA genes of different genotypes of V. cholerae strains through years. In conclusion, ribotyping analysis of environmental V. cholerae isolates showed a substantial genomic diversity supporting the fact that genetic changes within bacterial genome occurs during years in the environment, while only little changes may arise within the genome of clinical isolates. 相似文献