PMID- 10350607
OWN - NLM
STAT- MEDLINE
DCOM- 19990712
LR  - 20190610
IS  - 0006-3002 (Print)
IS  - 0006-3002 (Linking)
VI  - 1431
IP  - 2
DP  - 1999 May 18
TI  - Functionally important residues tyrosine-171 and serine-158 in sepiapterin
      reductase.
PG  - 306-14
AB  - The active site of sepiapterin reductase (SPR), which is a member of the
      NADP(H)-preferring short-chain dehydrogenase/reductase (SDR) family and acts as
      the terminal enzyme in the biosynthetic pathway of tetrahydrobiopterin cofactor
      (BH4), was investigated by truncation and site-directed mutagenesis. The
      truncation mutants showed that N-terminal and C-terminal residues contribute to
      bind coenzyme and substrate, respectively. The mutant rSPRA29V showed decreased
      activity; however, the A-X-L-L-S sequence, which has been reported as a putative 
      pterin binding site, was estimated to preferably work as a component in the
      region for binding coenzyme rather than substrate. Site-directed mutants of
      rSPRS158D, rSPRY171V, and rSPRK175I showed low, but significant, activity having 
      similar Km values and kcat/Km values less than 25%, for both sepiapterin and
      NADPH. Both amino acids Tyr-171 and Ser-158 are located within a similar distance
      to the carbonyl group of the substrate in the crystal structure of mouse SPR, and
      the double point mutant rSPRY171V+S158D was indicated to be inactive. These
      results showed that Ser-158, Tyr-171, and Lys-175 contributed to the catalytic
      activity of SPR, and both Tyr-171 and Ser-158 are simultaneously necessary on
      proton transfer to the carbonyl functional groups of substrate.
FAU - Fujimoto, K
AU  - Fujimoto K
AD  - Department of Biochemistry, Meikai University School of Dentistry, Sakado,
      Saitama 350-0283, Japan. kengo@dent.meikai.ac.jp
FAU - Ichinose, H
AU  - Ichinose H
FAU - Nagatsu, T
AU  - Nagatsu T
FAU - Nonaka, T
AU  - Nonaka T
FAU - Mitsui, Y
AU  - Mitsui Y
FAU - Katoh, S
AU  - Katoh S
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Netherlands
TA  - Biochim Biophys Acta
JT  - Biochimica et biophysica acta
JID - 0217513
RN  - 0 (DNA, Complementary)
RN  - 22150-76-1 (Biopterin)
RN  - 42HK56048U (Tyrosine)
RN  - 452VLY9402 (Serine)
RN  - EC 1.1.- (Alcohol Oxidoreductases)
RN  - EC 1.1.1.153 (sepiapterin reductase)
RN  - EGX657432I (sapropterin)
SB  - IM
MH  - Alcohol Oxidoreductases/*chemistry/genetics
MH  - Animals
MH  - Binding Sites
MH  - Biopterin/analogs & derivatives/biosynthesis
MH  - Cloning, Molecular
MH  - DNA, Complementary/metabolism
MH  - Escherichia coli/metabolism
MH  - Humans
MH  - Mutagenesis, Site-Directed
MH  - Mutation
MH  - Rats
MH  - Serine/chemistry
MH  - Tyrosine/chemistry
EDAT- 1999/06/03 00:00
MHDA- 1999/06/03 00:01
CRDT- 1999/06/03 00:00
PHST- 1999/06/03 00:00 [pubmed]
PHST- 1999/06/03 00:01 [medline]
PHST- 1999/06/03 00:00 [entrez]
AID - S0167-4838(99)00054-0 [pii]
AID - 10.1016/s0167-4838(99)00054-0 [doi]
PST - ppublish
SO  - Biochim Biophys Acta. 1999 May 18;1431(2):306-14. doi:
      10.1016/s0167-4838(99)00054-0.