title: Phosphorylation of spore coat proteins by a family of atypical protein kinases.
abstract: The modification of proteins by phosphorylation occurs in all life forms and is catalyzed by a large superfamily of enzymes known as protein kinases. We recently discovered a family of secretory pathway kinases that phosphorylate extracellular proteins. One member, family with sequence similarity 20C (Fam20C), is the physiological Golgi casein kinase. While examining distantly related protein sequences, we observed low levels of identity between the spore coat protein H (CotH), and the Fam20C-related secretory pathway kinases. CotH is a component of the spore in many bacterial and eukaryotic species, and is required for efficient germination of spores in Bacillus subtilis; however, the mechanism by which CotH affects germination is unclear. Here, we show that CotH is a protein kinase. The crystal structure of CotH reveals an atypical protein kinase-like fold with a unique mode of ATP binding. Examination of the genes neighboring cotH in B. subtilis led us to identify two spore coat proteins, CotB and CotG, as CotH substrates. Furthermore, we show that CotH-dependent phosphorylation of CotB and CotG is required for the efficient germination of B. subtilis spores. Collectively, our results define a family of atypical protein kinases and reveal an unexpected role for protein phosphorylation in spore biology.
authors.affiliation: Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093;
authors.forename: Kim B
authors.initials: KB
authors.lastname: Nguyen
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390;
authors.forename: Anju
authors.initials: A
authors.lastname: Sreelatha
authors.affiliation: Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093;
authors.forename: Eric S
authors.initials: ES
authors.lastname: Durrant
authors.affiliation: Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093;
authors.forename: Javier
authors.initials: J
authors.lastname: Lopez-Garrido
authors.affiliation: Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02106 Warsaw, Poland;
authors.forename: Anna
authors.initials: A
authors.lastname: Muszewska
authors.affiliation: Department of Experimental Design and Bioinformatics, Warsaw University of Life Sciences, 02787 Warsaw, Poland;
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Dudkiewicz
authors.affiliation: Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02106 Warsaw, Poland;
authors.forename: Marcin
authors.initials: M
authors.lastname: Grynberg
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390;
authors.forename: Samantha
authors.initials: S
authors.lastname: Yee
authors.affiliation: Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093;
authors.forename: Kit
authors.initials: K
authors.lastname: Pogliano
authors.affiliation: Departments of Biophysics and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390;
authors.forename: Diana R
authors.initials: DR
authors.lastname: Tomchick
authors.affiliation: Department of Experimental Design and Bioinformatics, Warsaw University of Life Sciences, 02787 Warsaw, Poland;
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Pawłowski
authors.affiliation: Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093; Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093 jedixon@ucsd.edu vincent.tagliabracci@utsouthwestern.edu.
authors.forename: Jack E
authors.initials: JE
authors.lastname: Dixon
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390; jedixon@ucsd.edu vincent.tagliabracci@utsouthwestern.edu.
authors.forename: Vincent S
authors.initials: VS
authors.lastname: Tagliabracci
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics; D001426:Bacterial Proteins / Q000737:chemistry; D036022:Capsid Proteins; D010766:Phosphorylation; D011494:Protein Kinases; D013171:Spores, Bacterial / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D036022:Capsid Proteins; D011494:Protein Kinases
keywords: CotB; CotG; CotH; kinase; phosphorylation