Adenosylcobinamide-phosphate guanylyltransferase explained

adenosylcobinamide-phosphate guanylyltransferase
Ec Number:	2.7.7.62
Go Code:	0043753

In enzymology, an adenosylcobinamide-phosphate guanylyltransferase is an enzyme that catalyzes the chemical reaction

GTP + adenosylcobinamide phosphate

\rightleftharpoons diphosphate + adenosylcobinamide-GDP

The two substrates of this enzyme are GTP and adenosylcobinamide phosphate; its two products are diphosphate and adenosylcobinamide-GDP.

This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is GTP:adenosylcobinamide-phosphate guanylyltransferase. Other names in common use include CobU, adenosylcobinamide kinase/adenosylcobinamide-phosphate, guanylyltransferase, and AdoCbi kinase/AdoCbi-phosphate guanylyltransferase. This enzyme is part of the biosynthetic pathway to cobalamin (vitamin B₁₂) in bacteria.

See also

• Cobalamin biosynthesis

References

• O'Toole GA, Escalante-Semerena JC . 1995 . Purification and characterization of the bifunctional CobU enzyme of Salmonella typhimurium LT2. Evidence for a CobU-GMP intermediate . J. Biol. Chem. . 270 . 23560 - 9 . 7559521 . 10.1074/jbc.270.40.23560 . 40 . free .
• Thompson TB, Thomas MG, Escalante-Semerena JC, Rayment I . 1998 . Three-dimensional structure of adenosylcobinamide kinase/adenosylcobinamide phosphate guanylyltransferase from Salmonella typhimurium determined to 2.3 A resolution . Biochemistry . 37 . 7686 - 95 . 9601028 . 10.1021/bi973178f . 21 . 10.1.1.565.1238 .
• Thompson TB, Thomas MG, Escalante-Semerena JC, Rayment I . 1999 . Three-dimensional structure of adenosylcobinamide kinase/adenosylcobinamide phosphate guanylyltransferase (CobU) complexed with GMP: evidence for a substrate-induced transferase active site . Biochemistry . 38 . 12995 - 3005 . 10529169 . 10.1021/bi990910x . 40 .
• Thomas MG, Thompson TB, Rayment I, Escalante-Semerena JC . 2000 . Analysis of the adenosylcobinamide kinase/adenosylcobinamide-phosphate guanylyltransferase (CobU) enzyme of Salmonella typhimurium LT2. Identification of residue His-46 as the site of guanylylation . J. Biol. Chem. . 275 . 27576 - 86 . 10869342 . 36 . 10.1074/jbc.M000977200 . free .
• Warren MJ, Raux E, Schubert HL, Escalante-Semerena JC . 2002 . The biosynthesis of adenosylcobalamin (vitamin B12) . Nat. Prod. Rep. . 19 . 390 - 412 . 12195810 . 10.1039/b108967f . 4 .