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1.
Diversity of 42 isolates from effective nodules of Pisum sativum in different geographical regions of China were studied using 16S rRNA gene RFLP patterns, 16S rRNA sequencing, 16S–23S rRNA
intergenic spacer (IGS) region RFLP patterns and G-C rich random amplified polymorphic DNA (RAPD). The isolates were distributed
in two groups on the basis of their 16S rRNA gene RFLP patterns. The 16S rRNA gene sequences of strains from 16S rRNA gene
RFLP patterns group I were very closely related (identities higher than 99.5%) to Rhizobium leguminosarum USDA 2370. Group II consisting of WzP3 and WzP15 was closely related to Rhizobium etli CFN42. The analysis of the 16S-23S IGS RFLP patterns divided the isolates into 18 genotypes and four groups. Group I was
clustered with R. leguminosarum USDA2370. Group II consisted of YcP2, YcP3 and CqP7. The strains of group III were distributed abroad. Group IV consisted
of WzP3, WzP15 and R. etli CFN42. RAPD divided the isolates into nine clusters in which group IV only consisted of YcP2 and the strains of group V and
IX were from Wenzhou and Xiantao, respectively. This assay demonstrated the geographical effect on genetic diversity of pea
rhizobia. 相似文献
2.
Typing of reference strains and isolates identified as Lactobacillus casei, Lactobacillus paracasei or Lactobacillus rhamnosus was carried out using randomly amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) analyses. Strains of L. paracasei were mainly grouped in the same cluster as those of L. casei. The RAPD fingerprints of strains ATCC 393 and ATCC 15820 differ from those of the L. rhamnosus and L. paracasei/casei strains further supporting classification of these strains as a separate group. The RAPD profiling could be used for classification and discrimination of isolates belonging to the L. casei group. 相似文献
3.
Pamphile João Alencar Azevedo João Lúcio 《World journal of microbiology & biotechnology》2002,18(5):391-396
The species Fusarium verticillioides (= F. moniliforme) is often found in maize seeds, constituting an important source of inoculum in the field. Fusarium spp., associated with symptomatic and asymptomatic plants, may be a primary causal agent of disease, a secondary invader or an endophyte. In the present work, endophytic fungi were isolated from two populations of Zea mays (BR-105 and BR-106) and their respective inbred lines. Within different inbred lines of maize, Fusarium was found at a frequency of 0 to 100% relative to the number of total isolated fungi. The frequency with which the genus occurred was practically the same in the two field sites (around 60%). Twenty-one F. verticillioides strains were analysed using the random amplified polymorphic DNA (RAPD) technique, employing 10 random primers. Variability analysis of endophytic isolates via RAPD showed genome polymorphism taxa of species around 60%. Endophytic isolates were clustered by their sites of origin. RAPD analysis clustered the endophytic isolates by their maize inbred lines hosts (Mil-01 to Mil-06), whereas at site A they clustered into two major groups related to the maize gene pool (BR-105 or BR-106 population). All strains isolated from seeds collected in Site A, except strains L9 and L10, were sub-grouped according to maize inbred lines. The analysis showed a discrete sub-grouping at site B. Results obtained here could be explained by a co-evolution process involving endophytic isolates of F. verticillioides and maize inbred lines. 相似文献
4.
V. R. Lunge N. Ikuta A. S. K. Fonseca D. Hirigoyen M. Stoll S. Bonatto L. S. Ozaki 《World journal of microbiology & biotechnology》1994,10(6):648-652
Genomic DNA of 13 Bradyrhizobium japonicum strains was prepared and analysed by restriction fragment length polymorphism (RFLP) with nif and nod probes, and by random amplified polymorphic DNA (RAPD) with 11 primers of arbitrary nucleotide sequence. Polymorphism was observed in both analyses. The RFLP and RAPD banding patterns of different strains were used to calculate genetic divergence and to construct phylogenetic trees, allowing studies on the relationships between the strains. RFLP with nif and nod probes permitted the separation of the strains into two divergent groups, whereas RAPD separated them into four main groups. RAPD allowed closely related strains to be distinguished. 相似文献
5.
Inglis PW Teixeira EA Ribeiro DM Valadares-Inglis MC Tigano MS Mello SC 《Current microbiology》2001,42(3):194-198
Cercospora caricis is of interest as a potential mycoherbicide for control of purple nutsedge, Cyperus rotundus, which is considered to be the world's worst weed. The genetic variation of a collection of Brazilian Ce. caricis isolated from Cy. rotundus was analyzed by using RAPD, RFLP with a telomeric probe, [TTAGGG]18 and sequencing of the ITS1-5.8S-ITS2 regions of the ribosomal RNA gene. The Brazilian isolates were also compared with a
Ce. caricis isolate from Florida, USA and with some other Cercospora species. A cluster of isolates from the Brazilian cerrado region was identified showing high genetic similarity. In contrast,
isolates originating in other geographic regions of Brazil were less than 50% and 25% related to the former group according
to similarity estimates produced from RAPD and telomeric RFLP analyses respectively. ITS sequence analysis did not support
taxonomic division of the Brazilian strains, but did confirm the distant relatedness of these strains to the Ce. caricis isolate from Florida. The data indicate a need for an extensive molecular survey of Cercospora species associated with the Cyperaceae.
Received: 12 July 2000 / Accepted: 5 September 2000 相似文献
6.
LH Lee YK Cheah S Mohd Sidik NS Ab Mutalib YL Tang HP Lin K Hong 《World journal of microbiology & biotechnology》2012,28(5):2125-2137
The present study aimed to isolate actinobacteria from soil samples and characterized them using molecular tools and screened
their secondary metabolites for antimicrobial activities. Thirty-nine strains from four different location of Barrientos Island,
Antarctica using 12 types of isolation media was isolated. The isolates were preceded to screening of secondary metabolites
for antimicrobial and antifungal activities. Using high-throughput screening methods, 38% (15/39) of isolates produced bioactive
metabolites. Approximately 18% (7/39), 18% (7/39), 10% (4/39) and 2.5% (1/39) of isolates inhibited growth of Candida albicans ATCC 10231T, Staphylococcus aurues ATCC 51650T, methicillin-resistant Staphylococcus aurues (MRSA) ATCC BAA-44T and Pseudomonas aeruginosa ATCC 10145T, respectively. Molecular characterization techniques like 16S rRNA analysis, Enterobacterial repetitive intergenic consensus—polymerase
chain reaction (ERIC-PCR), Random amplified polymorphic DNA (RAPD) and composite analyses were used to characterize the actinobacteria
strains. Analysis of 16S rRNA sequences is still one of the most powerful methods to determine higher taxonomic relationships
of Actinobacteria. Both RAPD and ERIC-PCR fingerprinting have shown good discriminatory capability but RAPD proved to be better in discriminatory
power than ERIC-PCR. Our results demonstrated that composite analysis of both fingerprinting generally increased the discrimination
ability and generated best clustering for actinobacteria strains in this study. 相似文献
7.
Jean-Marie Meyer Trân Van Van Alain Stintzi Odile Berge Günther Winkelmann 《Biometals》1995,8(4):309-317
Several strains of Burkholderia vietnamiensis, isolated from the rhizosphere of rice plants, and four strains formerly known as Pseudomonas cepacia including two collection strains and two clinical isolates were compared for siderophore production and iron uptake. The B. vietnamiensis (TVV strains) as well as the B. cepacia strains (ATCC 25416 and ATCC 17759) and the clinical isolates K132 and LMG 6999 were all found to produce ornibactins under iron starvation. The two ATCC strains of B. cepacia additionally produced the previously described siderophores, pyochelin and cepabactin. Analysis of the ratio of isolated ornibactins (C4, C6 and C8) by HPLC revealed nearly identical profiles. Supplementation of the production medium with ornithine (20 mm) resulted in a 2.5-fold increase in ornibactin synthesis. Ornibactin-mediated iron uptake was independent of the length of the acyl side chain and was observed with all strains of B. vietnamiensis and B. cepacia, but was absent with strains of Pseudomonas aeruginosa, Pseudomonas fluorescens and Pseudomonas stutzeri, known to produce pyoverdines or desferriferrioxamines as siderophores. These results suggest that ornibactin production is a common feature of all Burkholderia strains and that these strains develop an ornibactin-specific iron transport system which is distinct from the pyoverdine-specific transport in Pseudomonas strains. 相似文献
8.
Beatriz Ruiz-Díez Francisco Martín-Díez Juan L. Rodríguez-Tudela María Alvárez Joaquín V. Martínez-Suárez 《Current microbiology》1997,35(3):186-190
Four isolates of the pathogenic fungus Scedosporium prolificans (inflatum), causing a previously reported nosocomial outbreak in four leukemic patients, were typed by random amplification of polymorphic
DNA (RAPD) with two different 10-mer primers and PCR-fingerprinting with the core sequence of phage M13 as a single primer.
Both techniques allowed 10 additional clinical isolates of Scedosporium prolificans from different areas of Spain, including Scedosporium prolificans NCPF 2884, to be classified into 10 different molecular types. The four outbreak isolates consisted of three molecular types
with two patients sharing a similar strain, and the remaining two patients infected by two different strains.
Received: 28 January 1996 / Accepted: 28 March 1997 相似文献
9.
Genetic variability of the wild diploid wheat Triticum urartu revealed by RFLP and RAPD markers 总被引:4,自引:0,他引:4
R. Castagna S. Gnocchi M. Perenzin M. Heun 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(3-4):424-430
Genetic variability among 49 accessions of Triticum urartu was estimated by RFLP and RAPD marker analyses, and the two data sets were compared. One T. timopheevii accession and two accessions of T. durum and T. aestivum, respectively, were included to identify T. urartu accessions closely related to these polyploid wheats. Twenty eight RFLP clones and 29 RAPD primers generated 451 and 155
polymorphic bands, respectively. The three accessions from Armenia clustered together and were well separated from all other
accessions, which showed less pronounced geographical patterns. Genetic similarity and co-phenetic values calculated with
RAPD markers were very similar to those calculated with RFLP markers for the intraspecific comparisons, but not for the interspecific
comparisons. The identification of individual T. urartu accessions which are more related to polyploid wheats than others was not possible.
Received: 14 May 1996 / Accepted: 13 September 1996 相似文献
10.
Yoshiyuki Kawakami Ichiro Ueno Tsutomu Katsuyama Ken'ichi Furihata Hideki Matsumoto 《Microbiology and immunology》1994,38(11):891-895
Epidemiological typing, based on restriction fragment length polymorphism (RFLP) by pulsed-field gel electrophoresis (PFGE), was attempted for the 38 clinical isolates of Moraxella catarrhalis obtained at Shinshu University Hospital during the years 1987 and 1993. Digestion with SmaI or NotI generated well separable, 12 to 5 genomic DNA fragments ranging from 1,000 kb to 30 kb and the strains could be classified into 14 or 13 types, respectively. The electrophoretic profile differed with the strain in most of them and was hence useful to distinguish the each strain. Investigation for their RFLP have, however, suggested that majority of them, including the type strain ATCC25238, may have derived from a common ancestor. 相似文献
11.
Avi Eldar Sara Lawhon Paul F. Frelier Liliana Assenta Bruce R Simpson Patricia W Varner Herve Bercovier 《FEMS microbiology letters》1997,151(2):155-162
Streptococcus iniae (junior synonym S. shiloi) isolated from tilapia and trout in Israel and in the United States were subtyped by restriction length polymorphism (RFLP) based on PCR amplified 16S rDNA and by ribotyping. 16S rDNA RFLP discriminated between S. iniae and other fish pathogens but not between S. iniae strains. HindIII and EcoRI ribotypes of S. iniae discriminated American from Israeli strains rejecting the possibility of an epidemiological link between S. iniae infections in the two countries. Israeli strains isolated from tilapia and trout could not be completely differentiated. The S. iniae ATCC 29178T (T=Type strain) strain, isolated from a freshwater dolphin belonged to a ribotype different from those of all the fish isolates. 相似文献
12.
Hiroshi Asakura Sou-ichi Makino Toshikazu Shirahata Teizo Tsukamoto Hisao Kurazono Tetsuya Ikeda Kouichi Takeshi 《Microbiology and immunology》1998,42(10):683-688
The isolation and characterization of Shiga-like toxin (Stx)-producing Escherichia coli (STEC) from sheep are described. The distribution of stx genes in E. coli isolates was detected by PCR. When brain heart infusion (BHI) broth and novobiocin supplemented m-EC broth (N-mEC) were used as enrichment culture for the isolation of STEC, N-mEC, compared to BHI, showed clearly lower efficiency. Finally, 5 STEC isolates from 4 sheep were isolated and characterized by biochemical and genetical analysis. All of them were confirmed by ELISA and Vero cell cytotoxicity assay for the production of Stx. Moreover, some strains carried hemolysin and eaeA genes and harbored large plasmids. Based on their plasmid profiles, antibiotic patterns and PCR-based DNA fingerprinting analysis using random amplified polymorphic DNA (RAPD), all isolates were different from each other. Three of the isolates were identified to belong to serogroups O2, O153 and O165, respectively, and the STEC strains belonging to these serogroups had been isolated from STEC outbreaks in humans. Four months after the first isolation in July 1997, STEC from sheep #1 was isolated again. A new isolate, HI-11, was identified as STEC O2: Hnt. Simultaneously, 2 STEC, which were genetically and phenotypically different from each other, were isolated from the same sheep at intervals of 4 months. These results demonstrate that sheep may be an important animal for studying human STEC infections, and that further epidemiological surveys on STEC are necessary. 相似文献
13.
Two molecular methods were compared, random amplified polymorphic DNA (RAPD) and restriction endonuclease analysis (REA),
in order to evaluate their ability to discriminate, and to characterize Madurella mycetomatis strains isolated from human mycetomas in different parts of the world. Both methods were able to cluster the Madurella mycetomatis isolates into the same number of distinct typing groups. However, RAPD, presenting several advantages over REA such as its
rapidity, simplicity, and the accessibility for implementation in the laboratory, is a more sensitive and reproducible tool
for the study of Madurella mycetomatis epidemiology than REA.
Received: 24 March 1999 / Accepted: 24 June 1999 相似文献
14.
To prepare homologous DNA fragments as restriction fragment length polymorphism (RFLP) markers, the genes encoding phenol oxidase, chitinase, and xylanase were amplified from genomic DNA of Rosellinia necatrix strains. RFLP analysis using the amplified DNA fragments as probe was carried out, with segregation of the markers among two sets of F1 progenies isolated from an independent perithecium. RFLP was frequently found using rpo1 as the RFLP marker among strains of R. necatrix, which was isolated from single ascospores and the circumference of the perithecium. In each set, RFLPs of some F1 progenies were different from that of the parent strain. Random amplified polymorphic DNA (RAPD) also revealed that several strains, which were of different genotypes from the parent strain, were contained in the single ascospore culture isolated from the same perithecium. From these results, it is suggested that another strain, which was genetically different, was required for mating and development of the ascus in R. necatrix. Therefore, the life cycle in R. necatrix was presumed to be heterothallism. This is the first report about a heterothallic life cycle in R. necatrix. 相似文献
15.
Ping-Chung Liu Kuo-Kau Lee Kah-Ching Yii Guang-Hsiung Kou Shiu-Nan Chen 《Current microbiology》1996,33(2):129-132
Outbreaks of high mortality among the cultured kuruma prawn Penaeus japonicus without overt gross signs occurred during August and December of 1994 in I-Lan, Taiwan. Eleven luminous bacterial strains
were isolated from the hepatopancreas of moribund prawns from five different farms by use of tryptic soy agar (TSA, supplemented
with 2% NaCl) and/or thiosulfate citrate bile salt sucrose (TCBS) agar. These strains, together with our two previously unpublished
isolates, were characterized and identified to be Vibrio harveyi in comparison with two ATCC Type strains and one strain previously isolated from the tiger prawn, P. monodon.
Received: 22 November 1995 / Accepted: 24 February 1996 相似文献
16.
Polymerase chain reaction (PCR) products of nuclear 5.8S and internal transcribed spacer regions (ITS2) of rDNA from reference
cultures of Acremonium obclavatum (a rarely recognized species first reported from India) were compared with cultures of Acremonium spp. isolated from Georgia, USA. Digestion of amplicons sequentially with Hinfl and Sau3AI divided the isolates into four restriction fragment length polymorphism (RFLP) groups. A representative isolate of primary
colonizers of insulation facings from a building in Georgia appeared identical to the type culture of A. obclavatum, whereas other cultures from Indian soils showed variation in the ITS2 region that divided them into further subgroups. Reference
cultures of A. kiliense (ATCC 14489) and A. strictum (ATCC 10141) and two additional isolates from metropolitan Atlanta, assigned to this latter species complex on a morphological
basis, represented two additional RFLP groups both of which were distinct from the RFLP groups in A. obclavatum. A. kiliense and A. strictum could be placed into similar subgroups on the basis of morphological differences and distinct RFLP patterns.
Received: 6 June 1997 / Accepted: 22 July 1997 相似文献
17.
Kawanishi M Kijima M Kojima A Ishihara K Esaki H Yagyu K Takahashi T Suzuki S Tamura Y 《Letters in applied microbiology》2006,42(6):648-653
AIMS: To investigate the antimicrobial susceptibility and genetic characteristics of Photobacterium damselae ssp. piscicida isolates obtained from cultured Seriola in Japan. METHODS AND RESULTS: Minimal inhibitory concentrations of 14 antimicrobials for 74 isolates from Seriola in Japan in 2002 were determined. Isolates showed high frequencies of resistance to sulfamonomethoxine (SMMX) (97.3%), oxytetracycline (OTC) (77.0%), flumequine (FMQ) (77.0%), chloramphenicol (CP) (75.7%), kanamycin (KM) (63.5%) and oxolinic acid (OA) (62.0%), but low to ampicillin (ABPC) (2.8%). All isolates were susceptible to bicozamycin (BCM), fosfomycin (FOM) and florfenicol (FF). Of these isolates, 45 (60.8%) showed same resistance pattern (SMMX-OTC-FMQ-OA-CP-KM). In random amplified polymorphic DNA (RAPD) analysis, no difference was observed among our 74 field isolates and ATCC51736 isolated from Seriola in 1974 in Japan, but different from ATCC 17911 isolated from white perch in USA. CONCLUSIONS: FF, BCM, FOM and ABPC were useful antimicrobials for treating pseudotuberculosis. However, the frequency of multidrug resistance was high. RAPD analysis showed homogeneity of isolates from Seriola in Japan. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that some antimicrobials were still useful for treating pseudotuberculosis and that P. damselae ssp. piscicida strains of same origin might have spread among Seriola in Japan since 1974. 相似文献
18.
An outbreak of Candida parapsilosis fungemia involving 17 neonatal intensive care unit (NICU) patients was studied. There were 14 blood culture and nine colonizing
isolates from other sites available. The hands of NICU healthcare workers (HCW) yielded eight isolates. Screening of the isolates
by random amplified polymorphic DNA (RAPD) method showed only three profiles. Typing by restriction fragment length polymorphism
(RFLP) revealed all blood isolates were RFLP subtype VII-1. Among the nine infant colonizing isolates, there were four different
RFLP subtypes; four of the isolates were subtype VII-1. Seven of the eight isolates from HCW were RFLP subtype VII-1. The
majority of infant colonizers were not found in the blood, suggesting a possible direct spread of the epidemic subtype VII-1
strain from HCW hands to infant blood. The source of the infant colonizing strains is unclear, but non-VII-1 strains may be
largely of maternal origin and VII-1 strains from HCW. These findings reinforce prior studies that have implicated HCW hands
as the source of nosocomial, including neonatal, fungemia. 相似文献
19.
Saswati Nayak Radha Prasanna Boddupalli M. Prasanna Dina B. Sahoo 《World journal of microbiology & biotechnology》2007,23(11):1575-1584
A set of 24 strains belonging to the genus Anabaena (Phylum Cyanobacteria), isolated from diverse geographic locations in India, were evaluated along with three International
type strains of Anabaena (ATCC 29414, ATCC 29208 and ATCC 27899) for their morphological, physiological and biochemical diversity. The morphological
dataset, consisting of 58 variants for 15 characters, and SDS-PAGE protein profiles comprising 17 polymorphic bands were utilized
to differentiate the selected Anabaena strains and explore the patterns of diversity through cluster analysis. Physiological and biochemical characterization with
respect to nitrogen fixation and accumulation of chlorophyll and phycobiliproteins led to the identification of some highly
promising Anabaena strains for use as biofertilizers and source of pigments. The study highlighted the tremendous inter and intraspecific diversity
within the Anabaena isolates and indicated the potential as well as constraints of the morphological and protein profiling datasets for unambiguous
differentiation and analyses of diversity among the Anabaena strains. 相似文献
20.
Swedish soil isolates biochemically classified as Bacillus thuringiensis subsp. israelensis were further examined for genetic diversity by multilocus enzyme electrophoresis (MLEE), random amplified polymorphic DNA
analysis (RAPD), pulse field gel electrophoresis (PFGE), and Southern blotting, and were compared with reference strains.
All the tested strains belonging to the Bt. israelensis serotype H14 were found to be identical, as judged from the RAPD analysis. MLEE analysis gave a similar result; only one
H14 strain was found to differ from the remaining H14 strains by one null allele. PFGE analysis confirmed a very close relationship
between the H14 strains but revealed an SfiI restriction fragment of variable size. Southern blot analyses were carried out with probes for the chromosomally encoded
flagellin gene(s) and the plasmid-encoded mosquitocidal toxins. All probes gave similar hybridization patterns in the H14
strains. The mosquito toxin probes hybridized only to the H14 strains, except for one probe hybridizing to strain 6:3, which
was originally isolated from the same soil sample as strains 6:11 and 6:12. Because the RAPD, MLEE, and PFGE analyses showed
that strain 6:3 appears to be unrelated to strains 6:11 and 6:12, the presence of a mosquito toxin sequence in strain 6:3
may suggest that gene transfer has occurred.
Received: 8 July 1999 / Accepted: 9 August 1999 相似文献