title: Reisolation of the carbon monoxide utilizing hydrogen bacterium Pseudomonas carboxydovorans (Kistner) comb. nov.
abstract: From enrichment cultures four carbon monoxide utilizing bacteria were isolated; strain OM5 isolated from waste water was studied in detail. The cells are Gram-negative, slightly curved rods, motile by a single subpolarly inserted flagellum. The colonies are smooth, translucent and not slimy. The cells are able to grow autotrophically in mineral medium under an atmosphere of 40% CO, 5% O2 and 55% N2 at a doubling time of 20h (30 degrees C) or of 85% H2, 5% O2 and 10% CO2 at a doubling time of 7h. Heterotrophic growth occurred on organic acids such as acetate(td = 8h), pyruvate(td = 8h), lactate, crotonate, malate, succinate (td = 8h), formate (td = 35h) and glyoxylate as substrates. The enzyme system for carbon monoxide utilization is formed only during growth on CO; hydrogenase is present in cells grown on CO or on H2 + CO2 as well as grown on pyruvate. The rate of oxygen reduction by intact CO-grown cells is 3.7-fold higher in the presence of hydrogen than in the presence of carbon monoxide. During growth the stoichiometry of gas uptake was 6.1 CO + 2.8 O2 + H2O leads to CH2O +5.1 CO2. For the new isolate the name Pseudomonas carboxydovorans (Kistner) comb. nov. has been proposed.
mesh_terms: D002248:Carbon Monoxide / Q000378:metabolism*; D005407:Flagella / Q000648:ultrastructure; D005561:Formates / Q000378:metabolism; D006859:Hydrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism; D011549:Pseudomonas / Q000302:isolation & purification* / Q000502:physiology / Q000648:ultrastructure; D012722:Sewage; D009626:Terminology as Topic; D014871:Water Microbiology
chemical_list: D005561:Formates; D012722:Sewage; D002248:Carbon Monoxide; D006859:Hydrogen; D010088:Oxidoreductases