This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Woodson, J. D. Articles by Escalante-Semerena, J. C. Search for Related Content PubMed PubMed Citation Articles by Woodson, J. D. Articles by Escalante-Semerena, J. C.

The cobY Gene of the Archaeon Halobacterium sp. Strain NRC-1 Is Required for De Novo Cobamide Synthesis

Biomolecular Chemistry Department, School of Medicine,² Department of Bacteriology, University of Wisconsin—Madison, Madison, Wisconsin,¹ Department of Biological Sciences, Illinois State University, Normal, Illinois³

Received 13 June 2002/ Accepted 2 September 2002

Genetic and nutritional analyses of mutants of the extremely halophilic archaeon Halobacterium sp. strain NRC-1 showed that open reading frame (ORF) Vng1581C encodes a protein with nucleoside triphosphate:adenosylcobinamide-phosphate nucleotidyltransferase enzyme activity. This activity was previously associated with the cobY gene of the methanogenic archaeon Methanobacterium thermoautotrophicum strain H, but no evidence was obtained to demonstrate the direct involvement of this protein in cobamide biosynthesis in archaea. Computer analysis of the Halobacterium sp. strain NRC-1 ORF Vng1581C gene and the cobY gene of M. thermoautotrophicum strain H showed the primary amino acid sequence of the proteins encoded by these two genes to be 35% identical and 48% similar. A strain of Halobacterium sp. strain NRC-1 carrying a null allele of the cobY gene was auxotrophic for cobinamide-GDP, a known intermediate of the late steps of cobamide biosynthesis. The auxotrophic requirement for cobinamide-GDP was corrected when a wild-type allele of cobY was introduced into the mutant strain, demonstrating that the lack of cobY function was solely responsible for the observed block in cobamide biosynthesis in this archaeon. The data also show that Halobacterium sp. strain NRC-1 possesses a high-affinity transport system for corrinoids and that this archaeon can synthesize cobamides de novo under aerobic growth conditions. To the best of our knowledge this is the first genetic and nutritional analysis of cobalamin biosynthetic mutants in archaea.

This article has been cited by other articles:

• Escalante-Semerena, J. C. (2007). Conversion of Cobinamide into Adenosylcobamide in Bacteria and Archaea. J. Bacteriol. 189: 4555-4560 [Full Text]  
• Zayas, C. L., Escalante-Semerena, J. C. (2007). Reassessment of the Late Steps of Coenzyme B12 Synthesis in Salmonella enterica: Evidence that Dephosphorylation of Adenosylcobalamin-5'-Phosphate by the CobC Phosphatase Is the Last Step of the Pathway. J. Bacteriol. 189: 2210-2218 [Abstract] [Full Text]  
• Woodson, J. D., Escalante-Semerena, J. C. (2006). The cbiS Gene of the Archaeon Methanopyrus kandleri AV19 Encodes a Bifunctional Enzyme with Adenosylcobinamide Amidohydrolase and {alpha}-Ribazole-Phosphate Phosphatase Activities.. J. Bacteriol. 188: 4227-4235 [Abstract] [Full Text]  
• Buan, N. R., Rehfeld, K., Escalante-Semerena, J. C. (2006). Studies of the CobA-Type ATP:Co(I)rrinoid Adenosyltransferase Enzyme of Methanosarcina mazei Strain Go1.. J. Bacteriol. 188: 3543-3550 [Abstract] [Full Text]  
• Zayas, C. L., Woodson, J. D., Escalante-Semerena, J. C. (2006). The cobZ Gene of Methanosarcina mazei Go1 Encodes the Nonorthologous Replacement of the {alpha}-Ribazole-5'-Phosphate Phosphatase (CobC) Enzyme of Salmonella enterica.. J. Bacteriol. 188: 2740-2743 [Abstract] [Full Text]  
• Woodson, J. D., Reynolds, A. A., Escalante-Semerena, J. C. (2005). ABC Transporter for Corrinoids in Halobacterium sp. Strain NRC-1. J. Bacteriol. 187: 5901-5909 [Abstract] [Full Text]  
• Woodson, J. D., Escalante-Semerena, J. C. (2004). CbiZ, an amidohydrolase enzyme required for salvaging the coenzyme B12 precursor cobinamide in archaea. Proc. Natl. Acad. Sci. USA 101: 3591-3596 [Abstract] [Full Text]  
• Woodson, J. D., Zayas, C. L., Escalante-Semerena, J. C. (2003). A New Pathway for Salvaging the Coenzyme B12 Precursor Cobinamide in Archaea Requires Cobinamide-Phosphate Synthase (CbiB) Enzyme Activity. J. Bacteriol. 185: 7193-7201 [Abstract] [Full Text]