Biochemistry and Structural Biology  Back to Main

Faculty Detail    
Campus Address BBRB 406A Zip 2170
Phone  (205) 934-6289
Other websites PubMed Listing

Faculty Appointment(s)
Appointment Type Department Division Rank
Center  Comprehensive Cancer Center  Comprehensive Cancer Center Professor Emeritus
Primary  Microbiology  Microbiology Professor Emeritus

Graduate Biomedical Sciences Affiliations
Biochemistry and Structural Biology 
Cellular and Molecular Biology Program 

Biographical Sketch 
Charles L. Turnbough, Jr., Professor of Microbiology, received a B.A. in Chemistry from Monmouth College (1969) and an M.S. in Chemistry (1970) and a Ph.D. in Biochemistry (1975) from the University of Illinois. Dr. Turnbough’s graduate studies were with Dr. Robert L. Switzer on the selective inactivation of enzymes during sporulation in Bacillus subtilis. He did postdoctoral studies in molecular genetics in the laboratories of Dr. Bruce N. Ames at the University of California, Berkeley and Dr. John L. Ingraham at the University of California, Davis. In 1980, Dr. Turnbough joined the faculty of the Department of Microbiology at the University of Alabama at Birmingham (UAB), where he has worked his entire academic career. Dr. Turnbough served as an ASM Foundation for Microbiology Lecturer from 1993 to 1995 and was elected to Fellowship in the American Academy of Microbiology in 2011.

Society Memberships
Organization Name Position Held Org Link
American Society for Biochemistry and Molecular Biology     
American Association for the Advancement of Science     
American Society for Microbiology     

Research/Clinical Interest
Structure/Function of the Bacillus anthracis Exosporium; Bacterial Gene Regulation
There are two major research projects in the Turnbough laboratory. The first project is to determine the structure and function of the outermost exosporium layer of Bacillus anthracis spores, an established weapon of bioterrorism that causes the lethal disease anthrax. The exosporium is a bipartite structure consisting of a paracrystalline basal layer and an external hair-like nap. The filaments of the nap are formed by trimers of the collagen-like glycoprotein BclA, while the basal layer contains approximately 20 different proteins. Most basal layer proteins are structural elements that undergo posttranslational modifications necessary for stable exosporium assembly. The mechanisms and functions of several of these modifications are currently being actively studied. These modifications include multi-site phosphorylation of basal layer protein ExsB, glycosylation of BclA, and the apparently spontaneous covalent atachment of BclA to the basal layer protein BxpB. Based on the BclA-BxpB attachment mechanism, the Turnbough lab is also developing a new generally applicable vaccine platform that promotes a strong, lasting, and potentially multivalent immune response. The second project focuses on mechanisms of gene regulation in bacteria, particularly Escherichia coli, that involve reiterative transcription and/or transcription start site switching. Reiterative transcription is the repetitive addition of a nucleotide to the 3’ end of a nascent transcript due to slippage between the transcript and DNA template. Start site switching is the selection of alternative start sites at a single promoter, which results in the synthesis of transcripts with different potentials for translation. Previous studies have described control mechanisms in which reiterative transcription during initiation and start site switching act independently or together to regulate the expression of operons involved in pyrimidine biosynthesis and salvage. Recently, additional operons have been shown to use reiterative transcription and/or start site switching to regulate their expression by mechanisms unlike those previously described. These new mechanisms are presently being elucidated. In addition, studies are in progress to define the mechanisms of reiterative transcription and start site switching and the factors that modulate the extent of these reactions. Because the basic machinery of transcription is highly conserved throughout the biological world, it is possible that all life forms employ regulatory mechanisms analogous to those being unraveled in the Turnbough lab. Recent studies suggest that this is indeed the case and that such mechanisms contribute to human health.

Selected Publications 
Publication PUBMEDID
Chesnokova ON, McPherson SA, Steichen CT, Turnbough CL Jr. The spore-specific alanine racemase of Bacillus anthracis and its role in suppressing germination during spore development. J Bacteriol. 2009 Feb;191(4):1303-10. doi: 10.1128/JB.01098-08. Epub 2008 Dec 12.  19074397 
Oliva C, Turnbough CL Jr, Kearney JF. CD14-Mac-1 interactions in Bacillus anthracis spore internalization by macrophages. Proc Natl Acad Sci U S A. 2009 Aug 18;106(33):13957-62. doi: 10.1073/pnas.0902392106. Epub 2009 Jul 28.  19666536 
Dong S, Chesnokova ON, Turnbough CL Jr, Pritchard DG. Identification of the UDP-N-acetylglucosamine 4-epimerase involved in exosporium protein glycosylation in Bacillus anthracis. J Bacteriol. 2009 Nov;191(22):7094-101. doi: 10.1128/JB.01050-09. Epub 2009 Sep 11.  19749053 
Tan L, Turnbough CL Jr. Sequence motifs and proteolytic cleavage of the collagen-like glycoprotein BclA required for its attachment to the exosporium of Bacillus anthracis. J Bacteriol. 2010 Mar;192(5):1259-68. doi: 10.1128/JB.01003-09. Epub 2009 Dec 28.  20038593 
McPherson SA, Li M, Kearney JF, Turnbough CL Jr. ExsB, an unusually highly phosphorylated protein required for the stable attachment of the exosporium of Bacillus anthracis. Mol Microbiol. 2010 Jun;76(6):1527-38. doi: 10.1111/j.1365-2958.2010.07182.x. Epub 2010 Apr 23.  20444088 
Dong S, McPherson SA, Wang Y, Li M, Wang P, Turnbough CL Jr, Pritchard DG. Characterization of the enzymes encoded by the anthrose biosynthetic operon of Bacillus anthracis. J Bacteriol. 2010 Oct;192(19):5053-62. doi: 10.1128/JB.00568-10. Epub 2010 Jul 30.  20675481 
Turnbough CL Jr. Regulation of gene expression by reiterative transcription. Curr Opin Microbiol. 2011 Apr;14(2):142-7. doi: 10.1016/j.mib.2011.01.012. Epub 2011 Feb 19. Review.  21334966 
Tan L, Li M, Turnbough CL Jr. An unusual mechanism of isopeptide bond formation attaches the collagenlike glycoprotein BclA to the exosporium of Bacillus anthracis. MBio. 2011 May 31;2(3):e00084-11. doi: 10.1128/mBio.00084-11. Print 2011.  21628501 
Aldred KJ, McPherson SA, Wang P, Kerns RJ, Graves DE, Turnbough CL Jr, Osheroff N. Drug interactions with Bacillus anthracis topoisomerase IV: biochemical basis for quinolone action and resistance. Biochemistry. 2012 Jan 10;51(1):370-81. doi: 10.1021/bi2013905. Epub 2011 Dec 16.  22126453 
Kirchdoerfer RN, Herrin BR, Han BW, Turnbough CL Jr, Cooper MD, Wilson IA. Variable lymphocyte receptor recognition of the immunodominant glycoprotein of Bacillus anthracis spores. Structure. 2012 Mar 7;20(3):479-86. doi: 10.1016/j.str.2012.01.009.  22405006 

anthrax, Bacillus anthracis, exosporium, E. coli, gene regulation. reiterative transcription, transcription start site switching