Related Experiment Video
Updated: Aug 12, 2026

Pull-down of Calmodulin-binding Proteins
Published on: January 23, 2012
A calmodulin-like protein in the bacterial genus Streptomyces
Tohru Yonekawa1, Yasuo Ohnishi, Sueharu Horinouchi
1Department of Biotechnology, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.
Abstract:
The gene, named cabB, encoding a calmodulin-like protein of 70 amino acids containing two helix-loop-helix EF-hand motifs was cloned from Streptomyces coelicolor A3(2). cabB was transcribed from a single promoter throughout growth. The CabB protein produced in Escherichia coli was a monomer in solution, although it corresponded to one half of a dumbbell shape of the eukaryotic calmodulins. CabB bound calcium and upon binding of calcium its alpha-helix content was increased, as determined by circular dichroism spectroscopy. The growth of cabB-disruptants (mutant DeltacabB) on minimal agar medium containing calcium higher than 20 mM was delayed, suggesting that CabB has a role in calcium homeostasis by serving as a calcium buffer or transporter, as suggested for calerythrin in actinomycetes and the invertebrate sarcoplasmic calcium-binding proteins. Wide distribution of cabB almost exclusively in actinomycetes suggests a common role of EF-hand CabB-type proteins in these filamentous, soil-dwelling Gram-positive bacterial genera.
More Related Videos
09:08From a Natural Product to Its Biosynthetic Gene Cluster: A Demonstration Using Polyketomycin from Streptomyces diastatochromogenes Tü6028
Published on: January 13, 2017
09:26Identifying the Binding Proteins of Small Ligands with the Differential Radial Capillary Action of Ligand Assay (DRaCALA)
Published on: March 19, 2021
Related Concept Videos
Bacterial Signaling
Cytoskeletal Proteins in Bacteria
Calmodulin-dependent Signaling
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
Other Stress Responses in Bacteria
Bacterial Phylum Planctomycetes
Bacterial Phylum Actinobacteria