THE METHANOL OXIDATION GENES MXAFJGIR(S)ACKLD IN METHYLOBACTERIUM-EXTORQUENS

MxaJ is a protein of unknown function encoded by mxaJ in the mxaFJGI o peron. We have constructed a mxaJ mutant of M. extorquens with a delet ion which does not affect transcription of downstream genes. It contai ned cytochrome c(L) (MxaG), but neither subunit of methanol dehydrogen ase (MxaF and MxaI). MxaJ is probably involved in processing this enzy me. We have sequenced the region between mxaFJGI and five other methan ol oxidation genes, mxaACKLD; it includes one open reading frame (mxaR ) and a possible second open reading frame (mxaS), demonstrating the p resence in M. extorquens of the following gene cluster: mxaFJGIR(S)ACK LD.