EXCEEDTHE SPACE PROVIDED. Using a combination of organic chemistry, molecular biology, enzymology, and NMR spectroscopy the details of the biosynthesis of uroporphyrinogen III (theprecursor of heme and chlorophyll) and its subsequent transformation to vitamin B12,the anti-perinicious anemia factor, will be elucidated. Knowledge of the pathway including control mechanisms and genetic mapping will define intermediates important in diseases such as B12 deficiency and acute intermittent porphyria. All of the biosynthetic enzymes necessary for the formation of cobyrinic acid, the simplest B12 analog, will be overexpressed using the sequenced cbi genes of Salmonella typhimurium and the cob genes of Pseudomonas denitrificans and their mechanisms studied by NMR spectroscopy via13C- labeling. Finally, the multi-enzyme synthesis of advanced intermediates and of B12 itself will be addressed. PERFORMANCE SITE(S) (organization, city, state) Texas A&M University, College Station, Texas KEY PERSONNEL. See instructions on Page 11. Use continuation pages as needed to provide the required information in the format shown below. Name Organization Role on Project Scott, A. I. Dept. of Chemistry Texas A&M University Roessner, C. A. Dept. of Chemistry Texas A&M University Stolowich, N. J. Dept. of Chemistry Texas A&M University Santander, P. Dept. of Chemistry Texas A&M University Pichon, C. Dept. of Chemistry Texas A&M University Davidson Professor of Science Principal Investigator Senior Enzymologist i Cloning and Expression Senior Research Scientist NMR Spectroscopy/Enzyme mechanism Associate Research Scientist Isolation of Intermediates Associate Research Scientist Synthesis of 13C substrates/Bioconversion Jiminez, M. Dept. of Chemistry Research Assistant Texas A&M University Enzymology PHS 398 (Rev. 5/95) Page 2 * BB Number pages consecutively at the bottom throughout the application. Do not use suffixes such as 3a, 3b. ========================================Section End===========================================

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37DK032034-24
Application #
6883986
Study Section
Special Emphasis Panel (NSS)
Program Officer
May, Michael K
Project Start
1982-06-01
Project End
2009-01-31
Budget Start
2005-02-01
Budget End
2006-01-31
Support Year
24
Fiscal Year
2005
Total Cost
$520,158
Indirect Cost
Name
Texas A&M University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
078592789
City
College Station
State
TX
Country
United States
Zip Code
77845
Williams, Lakenya; Fresquet, Vicente; Santander, Patricio J et al. (2007) The multiple amidation reactions catalyzed by Cobyric acid synthetase from Salmonella typhimurium are sequential and dissociative. J Am Chem Soc 129:294-5
Kajiwara, Yasuhiro; Santander, Patricio J; Roessner, Charles A et al. (2006) Genetically engineered synthesis and structural characterization of cobalt-precorrin 5A and -5B, two new intermediates on the anaerobic pathway to vitamin B12: definition of the roles of the CbiF and CbiG enzymes. J Am Chem Soc 128:9971-8
Santander, Patricio J; Kajiwara, Yasuhiro; Williams, Howard J et al. (2006) Structural characterization of novel cobalt corrinoids synthesized by enzymes of the vitamin B12 anaerobic pathway. Bioorg Med Chem 14:724-31
Roessner, Charles A; Scott, A Ian (2006) Fine-tuning our knowledge of the anaerobic route to cobalamin (vitamin B12). J Bacteriol 188:7331-4
Chow, Siew Yin; Williams, Howard J; Huang, Qiulong et al. (2005) Studies on taxadiene synthase: interception of the cyclization cascade at the isocembrene stage with GGPP analogues. J Org Chem 70:9997-10003
Roessner, Charles A; Williams, Howard J; Scott, A Ian (2005) Genetically engineered production of 1-desmethylcobyrinic acid, 1-desmethylcobyrinic acid a,c-diamide, and cobyrinic acid a,c-diamide in Escherichia coli implies a role for CbiD in C-1 methylation in the anaerobic pathway to cobalamin. J Biol Chem 280:16748-53
Roessner, Charles A; Ponnamperuma, Krishan; Scott, A I (2002) Mutagenesis identifies a conserved tyrosine residue important for the activity of uroporphyrinogen III synthase from Anacystis nidulans. FEBS Lett 525:25-8
Roessner, C A; Santander, P J; Scott, A I (2001) Multiple biosynthetic pathways for vitamin B12: variations on a central theme. Vitam Horm 61:267-97
Santander, P J; Stolowich, N J; Scott, A I (1999) Chemoenzymatic synthesis of an unnatural tetramethyl cobalt corphinoid. Bioorg Med Chem 7:789-94
Spencer, P; Stolowich, N J; Sumner, L W et al. (1998) Definition of the redox states of cobalt-precorrinoids: investigation of the substrate and redox specificity of CbiL from Salmonella typhimurium. Biochemistry 37:14917-27

Showing the most recent 10 out of 12 publications