Microbial growth on C-1 compounds. 6. Oxidation of methanol, formaldehyde and formate by methanol-grown Pseudomonas AM-1.

Several studies have been made of the oxidation of C, compounds by micro-organisms grown on such compounds as sole source of carbon. In some cases, rather different results have been obtained by different workers. Kaneda & Roxburgh (1959) obtained evidence for an NAD+-linked methanol dehydrogenase in methanol-grown Pseudomonas PRL-W 4, whereas neither Harrington & Kallio (1960) nor Anthony & Zatman (1963) found such an enzyme in methanol-grown Pseudomonas methanica or Pseudlomonas sp. M 27 respectively. Instead, Harrington & Kallio ( 1960) suggested that methanol was oxidized by P. methanica '...via a catalaselinked peroxidase to formaldehyde which in turn is oxidized by a substrate specific aldehyde dehydrogenase requiringNADI and GSH. . . '. Anthony & Zatman (1963) showed by inhibitor experiments that methanol oxidation by Pseudomonas sp. M 27 was independent of catalase and instead found a methanol dehydrogenase that could be linked to phenazine methosulphate. It is somewhat unexpected that such closely similar bacteria should display different oxidation pathways for methanol, and to furnish further information on this question we present below a study of the oxidation of C1 compounds by methanol-grown Pseudomonas AM 1 and a comparative study of the oxidation of C1 compounds by three other types of bacteria.