@article{mbs:/content/journal/micro/10.1099/00221287-139-1-11, author = "Oozeer, F. and Page, M. D. and Ferguson, S. J. and Goodwin, P. M.", title = "Phenotypic characterization of c-type-cytochrome-deficient mutants of Methylobacterium extorquens AM1 and identification of two chromosomal regions essential for the production of c-type cytochromes", journal= "Microbiology", year = "1993", volume = "139", number = "1", pages = "11-19", doi = "https://doi.org/10.1099/00221287-139-1-11", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-139-1-11", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = "Four mutants of Methylobacterium extorquens AM1 which were deficient in the production of soluble c-type cytochromes have been isolated and characterized. They were unable to grow on methanol, ethanol or methylamine and c-type cytochromes were not detected in cell extracts by spectroscopy or in haem-stained SDS-polyacrylamide gels. Western blotting demonstrated that the mutants did not contain either the apo- or the holo-forms of cytochrome c L, although trace amounts of holo-cytochrome c H were detected. The mutants had only trace levels of methylamine dehydrogenase activity, suggesting a role for at least one of the c-type cytochromes in the production of the active form of this enzyme. Two regions of the M. extorquens AM1 chromosome which encode genes required for the synthesis of c-type cytochromes were identified and we have shown that, although the four mutants were phenotypically identical, they represent at least three complementation groups.", }