Genome sequence analysis of Clostridium aldehydum sp. nov., a novel bacterial species isolated from feces of an alcoholic patient. Enterocloster alcoholdehydrogenati strain:C5-48

Chronic consumption of excess alcohol increases the risk of colorectal cancer. Acetaldehyde (AcH) is produced during ethanol metabolism mediated by intestinal bacteria and colorectal mucosal cells. AcH associated with alcohol consumption is a potential risk factor for alcohol-related digestive tract cancers such as those of the esophagus, colon, or rectum. The role of intestinal bacteria in the accumulation of carcinogenic AcH in the colon and rectum after drinking has been implicated, although its ecophysiological details remain to be clarified. Because colorectal cancer develops from mucosal cells, the populations of AcH-accumulating bacteria inhabiting the colorectal mucosal surface may play a key role in alcohol-related colorectal cancer pathogenesis. We examined the ability of bacterial isolates from feces of alcoholic patients to produce and decompose AcH and identified various microorganisms that potentially accumulate AcH in the colon and rectum. These were collectively referred to as potential AcH accumulators (PAAs) . Among the PAA strains identified, we discovered a bacterial strain, C5-48T, which careful its taxonomic characteristics is similar to the known species of Clostridium but similarity values of the 16S rDNA is low. As a part of investigation of the physiological function of this strain, we performed whole genome sequence analysis of this strain.