SYMBIOTIC PRODUCTION OF PHENOLSULFATASE BY HUMAN GINGIVAL BACTERIA

Symbiotic production of phenolsulfatase by human gingival bacteria.

Evolution of Symbiotic Bacteria in the Distal Human Intestine

The adult human intestine contains trillions of bacteria, representing hundreds of species and thousands of subspecies. Little is known about the selective pressures that have shaped and are shaping this community's component species, which are dominated by members of the Bacteroidetes and Firmicutes divisions. To examine how the intestinal environment affects microbial genome evolution, we hav...

Symbiotic bacteria associated with stomach discs of human lice.

The symbiotic bacteria associated with the stomach disc, a large aggregate of bacteriocytes on the ventral side of the midgut, of human body and head lice were characterized. Molecular phylogenetic analysis of 16S rRNA gene sequences showed that the symbionts formed a distinct and well-defined clade in the Gammaproteobacteria. The sequences exhibited AT-biased nucleotide composition and acceler...

Differential ability of periodontopathic bacteria to modulate invasion of human gingival epithelial cells by Porphyromonas gingivalis.

Periodontitis is a polymicrobial infection caused by selected gram-negative bacteria including Porphyromonas gingivalis. Host cell invasion by P. gingivalis has been proposed as a possible mechanism of pathogenesis in periodontitis. The aim of the present study was to assess the influence of periodontopathogens on P. gingivalis invasion of gingival epithelial cells in polymicrobial infection. P...

Regulation of surface architecture by symbiotic bacteria mediates host colonization.

Microbes occupy countless ecological niches in nature. Sometimes these environments may be on or within another organism, as is the case in both microbial infections and symbiosis of mammals. Unlike pathogens that establish opportunistic infections, hundreds of human commensal bacterial species establish a lifelong cohabitation with their hosts. Although many virulence factors of infectious bac...