title: Cell division, one-carbon metabolism and methionine synthesis in a metK-deficient Escherichia coli mutant, and a role for MmuM.
abstract: An E. coli K-12 mutant deficient in S-adenosylmethionine (SAM) synthesis, i.e ΔmetK, but expressing a rickettsial SAM transporter, can grow in glucose minimal medium if provided with both SAM and methionine. It uses the externally provided (R)-enantiomer of SAM as methyl donor to produce most but not all of its methionine, by methylation of homocysteine catalysed by homocysteine methyltransferase (MmuM). The ΔmetK cells are also altered in growth and are twice as long as those of the parent strain. When starved of SAM, the mutant makes a small proportion of very long cells suggesting a role of SAM and of methylation in the onset of crosswall formation.
authors.affiliation: Biology Department, Concordia University, 1455 de Maisonneuve Ave., Montreal, Quebec H3G 1M8, Canada.
authors.forename: Z W
authors.initials: ZW
authors.lastname: El-Hajj
authors.affiliation: Biology Department, Concordia University, 1455 de Maisonneuve Ave., Montreal, Quebec H3G 1M8, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Reyes-Lamothe
authors.affiliation: Biology Department, Concordia University, 1455 de Maisonneuve Ave., Montreal, Quebec H3G 1M8, Canada.
authors.forename: E B
authors.initials: EB
authors.lastname: Newman
mesh_terms: D002244:Carbon / Q000378:metabolism*; D002455:Cell Division; D003470:Culture Media / Q000737:chemistry; D048168:Escherichia coli K12 / Q000166:cytology / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D050904:Homocysteine S-Methyltransferase / Q000378:metabolism*; D008715:Methionine / Q000096:biosynthesis*; D008716:Methionine Adenosyltransferase / Q000172:deficiency*; D012436:S-Adenosylmethionine / Q000378:metabolism
chemical_list: D003470:Culture Media; D029968:Escherichia coli Proteins; D002244:Carbon; D012436:S-Adenosylmethionine; D008715:Methionine; D050904:Homocysteine S-Methyltransferase; C494408:mmuM protein, E coli; C519385:MetK protein, E coli; D008716:Methionine Adenosyltransferase; D005947:Glucose