title: Tannin-protein complex-degrading enterobacteria isolated from the alimentary tracts of koalas and a selective medium for their enumeration.
abstract: Tannin-protein complex (T-PC)-degrading enterobacteria (T-PCDE) were isolated from the feces and from a layer of bacteria attached to the cecal wall of koalas. The T-PCDE were facultatively anaerobic, gram-negative, pleomorphic, nonmotile bacilli. The bacteria were also oxidase and catalase negative and resistant to vancomycin, reduced nitrates to nitrites, and grew on MacConkey agar. Growth on tannin-treated agar media showed a distinctive clear zone around the colony. From these observations, a selective agar plate medium (vancomycin- and tannin-treated Wilkins-Chalgren anaerobe agar) was developed to enumerate T-PCDE isolated from the feces of koalas. This medium was highly selective in the enumeration of the fecal T-PCDE and inhibited the growth of concomitant T-PC-degrading Streptococcus bovis. The T-PCDE were isolated from 10 of the 12 captive koalas studied; in 8 of these 10 koalas, the facultatively anaerobic bacterial flora was dominated (more than 60%) by T-PCDE. Viable numbers of T-PCDE were, in most of the animals, much larger (more than 100 times) than the numbers of T-PC-degrading S. bovis, suggesting that T-PCDE played a more active role in digesting T-PC in the alimentary tracts of koalas.
authors.affiliation: Veterinary Service and Research, Lone Pine Koala Sanctuary, Fig Tree Pocket, Brisbane, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Osawa
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D015169:Colony Count, Microbial / Q000379:methods; D003470:Culture Media; D004044:Dietary Proteins / Q000378:metabolism*; D004064:Digestive System / Q000382:microbiology*; D004755:Enterobacteriaceae / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D005243:Feces / Q000382:microbiology; D046911:Macromolecular Substances; D008394:Marsupialia; D010100:Oxygen / Q000378:metabolism; D013634:Tannins / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D003470:Culture Media; D004044:Dietary Proteins; D046911:Macromolecular Substances; D013634:Tannins; D010100:Oxygen