Abstracts

Biological sciences

Search abstracts:

Estimation of the relative abundance of different Bacteroides and Prevotella ribotypes in gut samples by restriction enzyme profiling of PCR-amplified 16S rRNA gene sequences

Article Abstract:

A study described an approach for determining the genetic composition of Bacteroides and Prevotella populations in gut contents based on selective amplification of 16S rRNA gene sequences followed by cleavage of the amplified material with restriction enzymes. The contributions of various ribotypes to total Bacteroides and Prevotella 16S rDNA were estimated followed by the estimation of the contribution of the sequences to total eubacterial 16S rDNA. The approach was found to be a rapid, convenient and widely applicable method for comparing the genotypic composition of bacterial populations in gut samples.

Genetic aspects, Bacterial genetics, Stomach, Restriction enzymes, DNA, DNA restriction enzymes

---

Fate of free DNA and transformation of the oral bacterium Streptococcus gordonii DL1 by plasmid DNA in human saliva

Article Abstract:

The survival of free DNA in human saliva and its degradation have been studied by using competitive polymerase chain reaction. The free DNA is a 520-bp target sequence from a recombinant plasmid, pVACMC1, after the admixture of the plasmid with freshly-sample human saliva. Results reveal that the plasmid DNA that has been exposed to degradation by human saliva can transform naturally-competent Streptococcus gordonii DL1 to erythromycin resistance. The transformation decreased rapidly with a half-life of 50 seconds.

Physiological aspects, Streptococcus, Saliva, Bacterial transformation, Extrachromosomal DNA

---

A xylan hydrolase gene cluster in Prevotella ruminicola B1(4): sequence relationships, synergistic interactions, and oxygen sensitivity of a novel enzyme with Exoxylanase and beta-(1,4)-xylosidase activities

Article Abstract:

The XynB enzyme in Prevotella ruminicola B14, a ruminal anaerobe, appears to be an oxygen-senstive exoxylanase whose sequence homology to two beta-xylosidases establishes a new family of beta-(1,4)-glycosidases. The xynB gene is closely linked to xynA, which encodes an endoxylanase, and the two enzyme products appear to act in synergy in releasing reducing sugars from oat spelt xylan.

Plant cells and tissues, Plant cells, Plant cell walls, Cell walls

Similar abstracts:

• Abstracts: Cytokine rescue of p53-dependent apoptosis and cell cycle arrest is mediated by distinct Jak kinase signaling pathways
• Abstracts: Genetic organization of the mle locus and identification of a mleR-like gene from Leuconostoc oenos. Molecular characterization of the gene encoding an 18-kilodalton small heat shock protein associated with the membrane of Leuconostoc oenos
• Abstracts: Estimation of methanogen biomass by quantitation of coenzyme M. A rapid and simple method for estimating sulfate reduction activity and quantifying inorganic sulfides
• Abstracts: Biosensor determination of the microscale distribution of nitrate, nitrate assimilation, nitrification, and denitrification in a diatom-inhabited freshwater sediment
• Abstracts: Species identification using genetic tools: the value of nuclear and mitochondrial gene sequences in whale conservation

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.