title: Identification of a novel function for the FtsL cell division protein from Escherichia coli K12.
abstract: Analysis of the essential cell division protein FtsL demonstrates the partial conservation of a cysteine-pair within the trans-membrane region which itself is flanked by histidine-pairs in the cytosol and periplasm. Similar arrangements of such amino acids are seen in proteins known to transport/bind metal ions in biological systems. Heterologous expression of ftsL in Escherichia coli K12 confers a Zn(II)-sensitive phenotype and alteration of the candidate metal-ion binding residues cysteine or histidine substantially alters this phenotype. Whilst the cysteine/histidine replacement derivatives of ftsL were able to complement an otherwise ftsL-null strain, the derivative carrying ftsL lacking the cysteine pair was sensitive to raised metal-ion concentrations in the media. We show that ftsL can confer a metal-ion sensitive phenotype and that trans-membrane cysteine residues play a role in FtsL function in elevated metal-ion concentrations.
authors.affiliation: Sense Proteomic Ltd., The Southern Centre, Unit 15, The Oxford Industrial Park, Mead Road, Yarnton, Oxford OX1 1QU, United Kingdom.
authors.forename: Dayle K
authors.initials: DK
authors.lastname: Blencowe
authors.forename: Sawsan
authors.initials: S
authors.lastname: Al Jubori
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Morby
mesh_terms: D000595:Amino Acid Sequence; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016384:Consensus Sequence; D003545:Cysteine / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006639:Histidine / Q000737:chemistry / Q000235:genetics; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D015032:Zinc / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D018797:Cell Cycle Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; C078387:ftsL protein, E coli; D006639:Histidine; D015032:Zinc; D003545:Cysteine