title: Cloning and expression of the gene for a novel protein from Mycobacterium smegmatis with functional similarity to eukaryotic calmodulin.
abstract: A calmodulin-like protein (CAMLP) from Mycobacterium smegmatis was purified to homogeneity and partially sequenced; these data were used to produce a full-length clone, whose DNA sequence contained a 55-amino-acid open reading frame. M. smegmatis CAMLP, expressed in Escherichia coli, exhibited properties characteristic of eukaryotic calmodulin: calcium-dependent stimulation of eukaryotic phosphodiesterase, which was inhibited by the calmodulin antagonist trifluoperazine, and reaction with anti-bovine brain calmodulin antibodies. Consistent with the presence of nine acidic amino acids (16%) in M. smegmatis CAMLP, there is one putative calcium-binding domain in this CAMLP, compared to four such domains for eukaryotic calmodulin, reflecting the smaller molecular size (approximately 6 kDa) of M. smegmatis CAMLP. Ultracentrifugation and mass spectral studies excluded the possibility that calcium promotes oligomerization of purified M. smegmatis CAMLP.
authors.affiliation: Bioprocess Engineering Group, Biotechnology Division, Chemical Science and Technology Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA. prasad.reddy@nist.gov
authors.forename: Prasad T
authors.initials: PT
authors.lastname: Reddy
authors.forename: C Rama
authors.initials: CR
authors.lastname: Prasad
authors.forename: P Hemalatha
authors.initials: PH
authors.lastname: Reddy
authors.forename: Dennis
authors.initials: D
authors.lastname: Reeder
authors.forename: Keith
authors.initials: K
authors.lastname: McKenney
authors.forename: Howard
authors.initials: H
authors.lastname: Jaffe
authors.forename: Mariana N
authors.initials: MN
authors.lastname: Dimitrova
authors.forename: Ann
authors.initials: A
authors.lastname: Ginsburg
authors.forename: Alan
authors.initials: A
authors.lastname: Peterkofsky
authors.forename: P Suryanarayana
authors.initials: PS
authors.lastname: Murthy
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D002147:Calmodulin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002417:Cattle; D003001:Cloning, Molecular; D017124:Conserved Sequence; D005057:Eukaryotic Cells; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D020102:Mycobacterium smegmatis / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA
chemical_list: D001426:Bacterial Proteins; D002147:Calmodulin; D002118:Calcium