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Bacteria Species (bacteria + species)
Selected AbstractsDetection of bacteria associated with harmful algal blooms from coastal and microcosm environments using electronic microarraysENVIRONMENTAL MICROBIOLOGY, Issue 3 2007Edward A. Barlaan Summary With the global expansion of harmful algal blooms (HABs), several measures, including molecular approaches, have been undertaken to monitor its occurrence. Many reports have indicated the significant roles of bacteria in controlling algal bloom dynamics. Attempts have been made to utilize the bacteria/harmful algae relationship in HAB monitoring. In this study, bacterial assemblages monitored during coastal HABs and bacterial communities in induced microcosm blooms were investigated. Samples were analysed using denaturing gradient gel electrophoresis (DGGE) of the 16S rRNA gene. DGGE bands with peculiar patterns before, during, and after algal blooms were isolated and identified. Probes for six ribotypes representing organisms associated with Chatonella spp., Heterocapsa circularisquama, or Heterosigma akashiwo were used for analysis on NanoChip electronic microarray. In addition, a new approach using cultured bacteria species was developed to detect longer (533 bp) polymerase chain reaction-amplified products on the electronic microarray. The use of fluorescently labelled primers allowed the detection of individual species in single or mixed DNA conditions. The developed approach enabled the detection of the presence or absence and relative abundance of the HAB-related ribotypes in coastal and microcosm blooms. This study indicates the ability of electronic microarray platform to detect or monitor bacteria in natural and induced environments. [source] Production of oxalates In Vitro by Microbes Isolated from Rock Surfaces with prehistoric paints in the Lower Pecos Region, TexasGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 1 2008Darren Hess Calcium oxalate-rich rock coatings are ubiquitous on limestone inside dry rock shelters and under bluff overhangs along canyon walls in southwestern Texas. Prehistoric pictographs occur in more than 250 such sites, and the ancient paints are encapsulated within the natural rock coating. Previous studies suggest lichens were the source of the oxalate; however, we report here that microbes cultured and isolated from samples of the coating produce oxalate in vitro. Twenty different bacteria species have been identified in samples from eight different sites, with Bacillus the most common genus, represented by five species. HPLC analyses of inoculated R2B medium after eight months of bacterial growth revealed the presence of oxalate ions in the solid phase of the growth medium. © 2008 Wiley Periodicals, Inc. [source] Genetic diversity and technological properties of Streptococcus thermophilus strains isolated from dairy productsJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2002D. Mora Aims: To evaluate the genetic diversity and the technological properties of 44 strains of Streptococcus thermophilus isolated from dairy products. Methods and Results: Strains were analysed for some relevant technological properties, i.e. exopolysaccharide (EPS) production, growth kinetic in skim milk medium, urease activity and galactose fermentation. The EPS production, determined by evaluating the colour of the colonies grown in ruthenium red milk agar, was observed in 50% of the analysed strains. Urease activity, determined by colorimetric and conductimetric methods, showed that 91% of the isolates, all except four, could hydrolyse urea. A conductimetric approach was also used for the evaluation of the overall metabolic behaviour in milk of Strep. thermophilus strains and the differences observed allowed grouping of the strains in seven different clusters. A total of 11 strains were able to produce acid in presence of galactose. Genetic diversity of Streptococcus thermophilus strains, evaluated by Random Amplified Polymorphic DNA fingerprinting (RAPD) and amplified epsC,D restriction analysis, allowed the identification of 21 different genotypes. Conclusions: Comparison between the genotypic and phenotypic data highlights an interesting correlation between some important technological properties and well-defined genotypes. Significance and Impact of the Study: The genetic and technological characterization carried out on several Strep. thermophilus strains of dairy origin should expand the knowledge on this important lactic acid bacteria species and lead to a simple, rapid, and reliable identification of strains on the basis of well-defined biotechnological properties. [source] 16S rDNA Sequence Analysis of Bacterial Isolates from Die-back Affected Sissoo Trees (Dalbergia sissoo Roxb.) in BangladeshJOURNAL OF PHYTOPATHOLOGY, Issue 9 2005H. Tantau Abstract A new form of disease called ,die-back' has been established in Dalbergia sissoo trees. This disease has reached epidemic proportions in Bangladesh as well as in other countries of South Asia and is characterized by browning of the leaves, signs of wilting, and trunk lesions with gum flow. The trees die within a few months. In order to investigate the causes of this die-back disease, samples were taken for a first trial in the Rajshahi division at two sites around Sherpur. For the isolation of bacteria, surface-sterilized plant material (leaves, twigs and trunk bark) from diseased trees was transferred to LB medium and incubated. After isolation of single colonies, various bacteria species could be identified by polymerase chain reaction analysis with two primers specific for highly conserved sequence regions in the bacterial 16S rDNA and by sequencing. First indications for the presence of bacteria with phytopathogenic potential were found. [source] Antifungal and Antibacterial Activity of the Newly Synthesized 2-Xanthone DerivativesARCHIV DER PHARMAZIE, Issue 1 2009Henryk Marona Abstract A series of 2-substituted xanthone derivatives 8,20 containing selected allyl, cinnamyl, morpholine, and imidazole moieties were synthesized and tested for their antifungal and antibacterial in-vitro properties. Of the newly synthesized derivatives, ten revealed antifungal activity especially against Trichophyton mentagrophytes (the biggest inhibition zones ranged 35 mm for 11 and 13). 2-(3-(Allylamino)propoxy)-9H -xanthen-9-one hydrochloride 9 inhibited growth of all of the examined fungal species. Significant efficacy against evaluated yeasts and dermatophytes was also observed for 6-chloro-2-methyl-9H -xanthen-9-one derivatives 11,13 containing encyclic amine moieties. Additionally, compounds 9, 11, and 12 hindered development of bacteria species but in a lesser degree. They were efficacious against Staphylococcus aureus, Escherichia coli, and Enterococcus faecalis. [source] | ||||||||||