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- *****************************************************************
- * 7,8-dihydro-6-hydroxymethylpterin-pyrophosphokinase signature *
- *****************************************************************
-
- All organisms require reduced folate cofactors for the synthesis of a variety
- of metabolites. Most microorganisms must synthesize folate de novo because
- they lack the active transport system of higher vertebrate cells which allows
- these organisms to use dietary folates. Enzymes involved in folate
- biosynthesis are therefore targets for a variety of antimicrobial agents such
- as trimethoprim or sulfonamides.
-
- 7,8-dihydro-6-hydroxymethylpterin-pyrophosphokinase (EC 2.7.6.3) (HPPK)
- catalyzes the attachment of pyrophosphate to 6-hydroxymethyl-7,8-dihydropterin
- to form 6-hydroxymethyl-7,8-dihydropteridine pyrophosphate. This is the first
- step in a three-step pathway leading to 7,8-dihydrofolate.
-
- Bacterial HPPK (gene folK or sulD) [1] is a protein of 160 to 270 amino
- acids. In the lower eukaryote Pneumocystis carinii, HPPK is the central domain
- of a multifunctional folate synthesis enzyme (gene fas) [2].
-
- As a signature for HPPK, we selected a conserved region located in the central
- section of these enzymes.
-
- -Consensus pattern: G-P-R-x(2)-D-L-D-[LIVM](2)
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
- -Last update: December 1992 / First entry.
-
- [ 1] Talarico T.L., Ray P.H., Dev I.K., Merrill B.M., Dallas W.S.
- J. Bacteriol. 174:5971-5977(1992).
- [ 2] Volpes F., Dyer M., Scaife J.G., Darby G., Stammers D.K., Delves C.J.
- Gene 112:213-218(1992).
-