moxFG region encodes four polypeptides in the methanol-oxidizing bacterium Methylobacterium sp. strain AM1

Journal Article · Sun May 01 00:00:00 EDT 1988 · J. Bacteriol.; (United States)

OSTI ID:6758141

Anderson, D J; Lidstrom, M E

The polypeptides encoded by a putative methanol oxidation (mox) operon of Methylobacterium sp. strain AM1 were expressed in Escherichia coli, using a coupled in vivo T7 RNA polymerase/promoter gene expression system. Two mox genes had been previously mapped to this region: moxF, the gene encoding the methanol dehydrogenase (MeDH) polypeptide; and moxG, a gene believed to encode a soluble type c cytochrome, cytochrome c/sub L/. In this study, four polypeptides of M/sub r/, 60,000, 30,000, 20,000, and 12,000 were found to be encoded by the moxFG region and were tentatively designated moxF, -J, -G, and -I, respectively. The arrangement of the genes (5' to 3') was found to be moxFJGI. The identities of three of the four polypeptides were determined by protein immunoblot analysis. The product of moxF, the M/sub r/-60,000 polypeptide, was confirmed to be the MeDH polypeptide. The product of moxG, the M/sub r/-20,000 polypeptide, was identified as mature cytochrome c/sub L/, and the product of moxI, the M/sub r/-12,000 polypeptide, was identified as a MeDH-associated polypeptide that copurifies with the holoenzyme. The identity of the M/sub r/-30,000 polypeptide (the moxJ gene product) could not be determined. The function of the M/sub r/-12,000 MeDH-associated polypeptide is not yet clear. However, it is not present in mutants that lack the M/sub r/-60,000 MeDH subunit, and it appears that the stability of the MeDH-associated polypeptide is dependent on the presence of the M/sub r/-60,000 MeDH polypeptide. Our data suggest that both the M/sub r/-30,000 and -12,000 polypeptides are involved in methanol oxidation, which would bring to 12 the number of mox genes in Methylobacterium sp. strain AM1.

• Research Organization: Univ. of Washington, Seattle (USA)
• OSTI ID: 6758141
• Journal Information: J. Bacteriol.; (United States), Vol. 170:5
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ALCOHOL DEHYDROGENASE
GENETIC MAPPING
CYTOCHROMES
METHANOL
OXIDATION
BACTERIA
GENE OPERONS
GENES
GENETIC ENGINEERING
RNA POLYMERASES
ALCOHOLS
CHEMICAL REACTIONS
ENZYMES
HEMIACETAL DEHYDROGENASES
HYDROXY COMPOUNDS
MAPPING
MICROORGANISMS
NUCLEOTIDYLTRANSFERASES
ORGANIC COMPOUNDS
OXIDOREDUCTASES
PHOSPHORUS-GROUP TRANSFERASES
PIGMENTS
POLYMERASES
PROTEINS
TRANSFERASES
550400* - Genetics