Abstract

Using a combination of organic chemistry, molecular biology, enzymology, and NMR spectroscopy the details of the biosynthesis of uroporphyrinogen III (the precursor 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 over-expressed using the sequenced cbi genes of Salmonella typhimurium and the cob genes of Pseudomonas denitrificans and their mechanisms studies by NMR spectroscopy ia 13C- labeling. Finally, the multi-enzyme synthesis of advanced intermediates and of B12 itself will be addressed.

  Funding Agency

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 #
5R37DK032034-20
Application #
6350647
Study Section
Metallobiochemistry Study Section (BMT)
Program Officer
May, Michael K
Project Start
1982-06-01
Project End
2004-01-31
Budget Start
2001-02-01
Budget End
2002-01-31
Support Year
20
Fiscal Year
2001
Total Cost
$370,408
Indirect Cost

  Institution

Name
Texas A&M University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
047006379
City
College Station
State
TX
Country
United States
Zip Code
77845

  Publications

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