ABSTRACT
We conducted the comparative study of seven different methods of total DNA extraction from human feces. All these methods are recommended in protocols for metagenomic analysis of human gut microbiota. We studied the relative quantity of human DNA calculated from shotgun sequencing on a SOLiD 4 genetic analyzer of metagenomic samples. It was shown that either initial amount of feces or a method applied for total DNA extraction do not affect on final relative human DNA abundance, which is less than 1% in healthy people. Invariance of this parameter allows to consider increased abundance of human DNA in metagenomic samples as a potential marker of inflammatory bowel diseases.
Subject(s)
DNA/genetics , Feces/chemistry , Intestines/microbiology , Metagenome , Microbiota/genetics , Adult , DNA/isolation & purification , Feces/microbiology , Female , HumansABSTRACT
The properties of the isolated Pseudomonas aeruginosa bacteriophage phiPMG1 include the lytic infection cycle, and the formation of a broad halo (semi-transparent zone) around the plaques. We consider phiPMG1 as a potential member of therapeutic cocktails of live phages, and as a source of peptidoglycan and lipopolysaccharide degrading enzymes. Partial sequencing of phiPMG1 genome has revealed high similarity with known temperate P. aeruginosa phage D3. An open reading frame encoding lytic transglycosilase was identified in the genome. This enzyme PMG MUR was obtained in recombinant form, and its activity and substrate specificity has been studied.
Subject(s)
Bacteriophages/enzymology , N-Acetylmuramoyl-L-alanine Amidase/genetics , Pseudomonas aeruginosa/virology , Amino Acid Sequence , Bacteriophages/ultrastructure , Enzyme Stability , Genome , Humans , Molecular Sequence Data , N-Acetylmuramoyl-L-alanine Amidase/chemistry , N-Acetylmuramoyl-L-alanine Amidase/metabolism , Pseudomonas aeruginosa/genetics , Sequence Analysis, DNAABSTRACT
Inclusion membrane proteins belong to the family of unique chlamydial proteins. Members of this family attract attention of scientists because of the following characteristics: Inc-proteins are localized in the inclusion membrane, these proteins have been found in all chlamydial species, expression of the most part of its genes begins during first hours from the infection of cell culture. Biological functions of Inc-proteins remain unknown, but these proteins are suggested to play a key role in process of the development the chlamydial infection.
