Open AccessCloning and Expression of the Gene for a Novel Protein from Mycobacterium smegmatis with Functional Similarity to Eukaryotic Calmodulin
Author(s) -
P.G. Reddy,
C. Venkata Siva Rama Prasad,
P.G. Reddy,
Dennis J. Reeder,
Keith McKenney,
Howard Jaffe,
Maria. Dimitrova,
Ann Ginsburg,
Alan Peterkofsky,
P. S. Murthy
Publication year - 2003
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.185.17.5263-5268.2003
Subject(s) - calmodulin , biology , mycobacterium smegmatis , biochemistry , peptide sequence , open reading frame , microbiology and biotechnology , gene , enzyme , mycobacterium tuberculosis , medicine , tuberculosis , pathology
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.