Isolation of bacteria and fungi from human sputum and faeces using carbon monoxide as source of energy and carbon

Abstract

Seventy-five sputa and 10 faeces of human origin were examined for organisms capable of growing in carbon monoxide (CO). Specimens were plated onto a buffered agar medium containing trace vitamins, and incubated (2–4 weeks) in 60% v/v CO as the sole source of carbon and energy. All specimens yielded growth except for three sputa; many individual colonies were shown to comprise at least two different organisms. While no recognized carboxydotrophs were found, presumptive identification revealed that streptococci, staphyloccoci, coliform bacilli, yeasts and moulds were all represented. Using a specific enzyme test, evidence for CO dehydrogenase activity was found in a significant proportion of mixed and purified cultures. These studies indicate that CO-tolerant organisms which may be using CO as a source of carbon and energy are associated with man.