ライフサイエンスコーパス: pterin

1 ive to the presence of the substrate and the pterin.

2 a bridging position between the iron and the pterin.

3 yl group at a C horizontal lineN bond of the pterin.

4 cted a GSH binding site adjacent to the N-NO-pterin.

5 ,7,8-tetrahydro-L-biopterin (H(4)B) or other pterins.

6 t no other aminated purines, pyrimidines, or pterines.

7 x 10(6); pterin-7-carboxylate, 3.7 x 10(6); pterin, 3.3 x 10(6); hydroxymethylpterin, 1.2 x 10(6); b

8 es and identified a novel deletion in PCBD1 (pterin-4 alpha-carbinolamine dehydratase/dimerization co

9 The iron is 5.6 A from the pterin 4a carbon which is hydroxylated in the enzymatic

10 Pterin 4a-carbinolamine dehydratase is bifunctional in m

11 P. aeruginosa PhhA plus the recycling enzyme pterin 4a-carbinolamine dehydratase, PhhB, rescues tyros

12 Pterin-4a-carbinolamine dehydratase (PCD) is a highly co

13 Targeting assays further indicated that pterin-4a-carbinolamine dehydratase, which regenerates t

14 ptional activity of the bifunctional protein pterin-4a-carbinolamine dehydratase/dimerization cofacto

15 Pterin-4a-carbinolamine dehydratases (PCDs) recycle oxid

16 codes for a protein with distant homology to pterin-4alpha-carbinolamine dehydratase (PCD) enzymes.

17 Like DCoH, DCoH2 forms a tetramer, displays pterin-4alpha-carbinolamine dehydratase activity, and bi

18 factor of hepatocyte nuclear factor 1 (DCoH)/pterin-4alpha-carbinolamine dehydratases (PCD)-like prot

19 fied in this search were isoxanthopterin and pterin 6-carboxylate.

20 alyze the deamination of isoxanthopterin and pterin 6-carboxylate.

21 d by dihydropterins but not by most oxidized pterins, 6-hydroxymethylpterin being an exception.

22 ranged from 3.6 microm to 1.7 mm, those for pterin-6-aldehyde and dihydropterin-6-aldehyde being 36

23 f NADPH-dependent reductase activity against pterin-6-aldehyde and its dihydro form were detected in

24 First, when pterin-6-aldehyde or 6-hydroxymethylpterin was supplied

25 reduction and oxidation of the side chain of pterin-6-aldehyde were readily detected.

26 Pools of the pterin oxidation end-product pterin-6-carboxylate are, likewise, fairly small (3-37%)

27 ) [M(-1) s(-1)]): formylpterin, 5.2 x 10(6); pterin-6-carboxylate, 4.0 x 10(6); pterin-7-carboxylate,

28 me utilized six column matrices, including a pterin-6-carboxylic acid affinity column.

29 Neither pterin-6-carboxylic acid nor folic acid bind to the crys

30 els of neopterin, pterine, xanthopterin, and pterin-6-carboxylic acid were found to be significantly

31 vo synthesis/recycling and regulation of the pterin (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin (6BH4)

32 x 10(6); pterin-6-carboxylate, 4.0 x 10(6); pterin-7-carboxylate, 3.7 x 10(6); pterin, 3.3 x 10(6);

33 ergo oxidative cleavage in vivo, releasing a pterin aldehyde fragment that can be re-used in folate s

34 ted that the activity would maintain in vivo pterin aldehyde pools at extremely low levels (<0.2 pmol

35 0310 gene caused only a minor change in seed pterin aldehyde reductase activity.

36 ants of At1g10310, previously described as a pterin aldehyde reductase in folate metabolism.

37 An Arabidopsis gene (At1g10310) encoding a pterin aldehyde reductase was identified by searching th

38 We conclude that pterin aldehyde salvage in plants involves multiple, gen

39 In addition to pterin aldehydes, it catalyzed the reduction of diverse

40 All three bisubstrate analogues consist of a pterin, an adenosine moiety, and a link composed of 2-4

41 The redox-stable pterin analogs appear to bind to NOS in a different mann

42 Reconstitution with the redox-stable pterin analogs was neither time- nor thiol-dependent.

43 Reptiles use pterin and carotenoid pigments to produce yellow, orange

44 gnetic signal to the molecular clock using a pterin and flavin adenine dinucleotide (FAD) as chromoph

45 1 (PTR1) is a novel broad spectrum enzyme of pterin and folate metabolism in the protozoan parasite L

46 tion of such oxidized pterins is crucial for pterin and folate salvage.

47 e first report of close interactions between pterin and iron in an enzyme active site.

48 Heme propionate interactions with pterin and L-Arg suggest that pterin has electronic infl

49 s in vivo undergo oxidative cleavage, giving pterin and p-aminobenzoylglutamate (pABAGlu) moieties.

50 means for regulating iNOS activity via N-NO-pterin and S-NO-Cys modifications.

51 k and zinc-binding region that interact with pterin and stabilize the mNOS(ox) dimer.

52 While the function of participating pterin and the roles of Nox, Npx, CynD, and CA in the CN

53 ented with 5-formyltetrahydrofolate (lacking pterins and depleted in dihydrofolate) and gcvP glyA mut

54 and showed similar catalytic properties with pterins and folates (pH dependence, substrate inhibition

55 ate biosynthesis were ablated, folE (lacking pterins and folates) and folP (lacking folates) mutants

56 PTR1 displays broad-spectrum activity with pterins and folates, provides a metabolic bypass for inh

57 a 1,250-fold and 2- to 4-fold enhancement of pterins and folates, respectively.

58 Elevated levels of pterins and nitric oxide (NO) are observed in patients w

59 Folates are synthesized de novo from pterins and para-amino benzoic acid, which are subsequen

60 The enzyme participates in the salvage of pterins and represents a target for the development of i

61 sence of monoamines and their cofactors (the pterins and vitamin B6 (pyridoxal phosphate (PLP))) in h

62 cs of WT TH, which produces Fe(IV)=O + 4a-OH-pterin, and E332A TH, which does not, shows that the E33

63 actor 1 (HNF1), two active centers that bind pterins, and a saddle-shaped surface that resembles nucl

64 Activity of the pterin- and folate-salvaging enzymes pteridine reductase

65 ive iNOS monomer-heme-inhibitor complex in a pterin- and l-arginine-independent manner.

66 BH(4) in its reduced form, In restoring the pterin- and/or substrate-binding capability of the E. co

67 -coordinate site when both L-Phe and reduced pterin are present in the active site.

68 ing that both a 5C Fe(II) and a redox-active pterin are required for coupled O(2) reaction.

69 coulometric electrochemical detection (ED), pterins are analyzed by HPLC with coupled coulometric el

70 Pterins are natural cofactors for a wide range of enzyme

71 generated are consistent with a role for the pterin as an electron donor in product formation; this r

72 the cofactor and decreased the affinity for pterin, as determined by the K(D) values of the mutant p

73 ant enzymes shows that although both oxidize pterin at more than twice the rate of wild-type enzyme,

74 were independent of pterin oxidation state: pterin binding affinity, and its ability to shift the he

75 -dihydrobiopterin and iron shows the mode of pterin binding and the proximity of its hydroxylated 4a

76 The structural comparison also reveals that pterin binding does not preferentially stabilize the dim

77 tb DHPS structure reveals a highly conserved pterin binding pocket that may be exploited for the desi

78 To identify such inhibitors and map the pterin binding pocket, we have performed virtual screeni

79 Pterin binding refolds the central interface region, rec

80 Compounds that bind to the pterin binding site of DHPS, as opposed to the p-amino b

81 tical limit, consistent with the coupling of pterin binding to the movement of a surface loop.

82 nal changes are seen in the active site upon pterin binding.

83 This substructure, together with the pterin-binding pocket, explains the roles of the conserv

84 switch region (residues 103-111) preceding a pterin-binding segment exchange N-terminal beta-hairpin

85 The pterin binds in the second coordination sphere of the ca

86 The pterin binds on one face of the large active-site cleft,

87 t a core gene in the housekeeping pathway of pterin biosynthesis has been coopted for bright colorati

88 TP cyclohydrolase-1 in plants would increase pterin biosynthesis with a concomitant enhancement of fo

89 which catalyzes the first committed step in pterin biosynthesis, was a rate-limiting step in pterin

90 erin can outrank folate as an end product of pterin biosynthesis.

91 structural changes are observed between the pterin bound and the nonliganded enzyme.

92 The reactivity of pterin-bound and pterin-free iNOS(heme) was examined, us

93 iphosphate (DHNTP) is the second step in the pterin branch of the folate synthesis pathway.

94 ediates the first and committing step of the pterin branch of the folate-synthesis pathway.

95 properly oriented for formation of an Fe-OO-pterin bridge and an open coordination position is avail

96 iNOS(heme) is isolated without bound pterin but can be readily reconstituted with (6R)-5,6,7,

97 tablishing that E. coli can take up oxidized pterins but cannot reduce them.

98 ontributes to the correct positioning of the pterin, but has no direct function in the catalytic reac

99 in a bridging position optimally between the pterin C-4a and iron atom prior to substrate hydroxylati

100 hows NO production to be dependent on both a pterin-centered radical and activated oxygen.

101 yme with l-arginine was used to generate the pterin-centered radical, followed by peroxide shunt chem

102 The part of the pterin closest to the iron is the O-4 carbonyl oxygen at

103 and Phe254 to the normal positioning of the pterin cofactor and catalytic activity of hPheOH.

104 The unprecedented involvement of the pterin cofactor as a single electron donor is unique amo

105 soforms is the amino acid composition of the pterin cofactor binding site that is adjacent to the NOS

106 ts support a dual redox cycling role for the pterin cofactor during NOS turnover of NHA with particul

107 e previous paradoxes regarding this uncommon pterin cofactor in NOS and suggest means for regulating

108 d active site, the most critical role of the pterin cofactor in NOS appears to be in electron transfe

109 The pterin cofactor is in an ideal orientation for dioxygen

110 Isozyme differences were observed in the pterin cofactor site, the heme propionate, and inhibitor

111 These results demonstrate that the bound pterin cofactor undergoes a one-electron oxidation (to f

112 to P4), each of which along with a source of pterin cofactor was obligately required for CNO activity

113 rosine in the presence of oxygen and reduced pterin cofactor.

114 network with an aqua ligand on iron and the pterin cofactor.

115 , and 1 Ca atom per subunit, together with a pterin cofactor.

116 ealed an unexpected N-NO modification on the pterin cofactor.

117 orial dithiolene sulfur atoms from a pair of pterin cofactors and a Se atom of the selenocysteine-140

118 olamine dehydratases (PCDs) recycle oxidized pterin cofactors generated by aromatic amino acid hydrox

119 cium pentahydrate (DCP), a calcium-complexed pterin compound, has previously been shown to inhibit hu

120 y in Escherichia coli and purified through a pterin-conjugated Sepharose affinity column.

121 f TH undergo 6C --> 5C conversion with tyr + pterin, consistent with the general mechanistic strategy

122 sis of methotrexate-gamma-Glu4, all possible pterin-containing cleavage products (methotrexate and me

123 archaea is dependent on the synthesis of the pterin-containing cofactor tetrahydromethanopterin (H4MP

124 Pterin-containing natural products have diverse function

125 e pterin ring distinguish MPT from all other pterin-containing natural products.

126 yme is not a member of the large class of Mo-pterin-containing oxotransferases which incorporate oxyg

127 Cryptochromes are flavin/pterin-containing proteins that are involved in circadia

128 Previous virtual screens revealed that pterins could bind in the specificity pocket of ricin an

129 ggests that the first step of an undescribed pterin degradation pathway is catalyzed by Arad3529.

130 Tryptophan hydroxylase is a pterin-dependent amino acid hydroxylase that catalyzes t

131 Alternatively, structures of the pterin-dependent and Rieske dioxygenases, which do not h

132 s in the mechanisms of the nonheme iron- and pterin-dependent aryl amino acid hydroxylases.

133 enylalanine levels, the enzyme catalyzes the pterin-dependent conversion of phenylalanine to tyrosine

134 Tyrosine hydroxylase (TyrH) is a pterin-dependent enzyme that catalyzes the hydroxylation

135 The catalytic domains of the pterin-dependent enzymes phenylalanine hydroxylase and t

136 support the function of as yet unrecognized pterin-dependent enzymes.

137 served in all three members of the family of pterin-dependent hydroxylases, phenylalanine hydroxylase

138 ues which are conserved across the family of pterin-dependent hydroxylases.

139 duce nitrogen oxides from L-Arg and NHA in a pterin-dependent manner, but that the regulation and pur

140 Tyrosine hydroxylase (TyrH) is a pterin-dependent mononuclear non-heme aromatic amino aci

141 Tyrosine hydroxylase (TH) is a pterin-dependent nonheme iron enzyme that catalyzes the

142 omonas fluorescens NCIMB 11764 catalyzes the pterin-dependent oxygenolytic cleavage of cyanide (CN) t

143 ethylobacterium extorquens AM1 possesses two pterin-dependent pathways for C(1) transfer between form

144 Methylobacterium extorquens AM1 contains two pterin-dependent pathways for C(1) transfers, the tetrah

145 the data reveal that during NO synthesis all pterin-dependent steps up to and including heme iron red

146 or (Moco) consists of a unique and conserved pterin derivative, usually referred to as molybdopterin

147 hydrofolate to p-aminobenzoylglutamate and a pterin derivative.

148 ion and interconversion of a selected set of pterins (dihydroneopterin, hydroxymethyldihydropterin, d

149 The pterin-dithiolene cofactor is an essential component of

150 sulfite oxidase enzyme families contain one pterin-dithiolene cofactor ligand bound to a molybdenum

151 sites contain a metal chelated by one or two pterin-dithiolene cofactor ligands, has lent new signifi

152 indicate a preference for the physiological pterin during hydroxylation.

153 We report a pterin electrocatalyst, 6,7-dimethyl-4-hydroxy-2-mercapt

154 R1) enabled rescue of the mutant by oxidized pterins, establishing that E. coli can take up oxidized

155 Pteridines, such as pterins, folates, and flavins, are heterocyclic metaboli

156 The bound pterin forms hydrogen bonds from N-8 to the main-chain c

157 nts to a potentially noninnocent role of the pterin fragment in pyranopterin Mo enzymes.

158 Heme and metal content of pterin-free and H(4)B-reconstituted NOS were also measur

159 , together with dithiothreitol (DTT), to the pterin-free ferric low-spin oxygenase domain (gamma(MAX)

160 ical was not observed with 4-amino-H(4)B- or pterin-free HDiNOS with either substrate.

161 Pterin-free inducible nitric oxide synthase (iNOS) was r

162 Here, we characterize pterin-free inducible NOS (iNOS) and iNOS reconstituted

163 t both electrons for the oxidation of NHA by pterin-free iNOS(heme) are derived from dithionite.

164 e of a bound, redox-active tetrahydropterin; pterin-free iNOS(heme) or iNOS(heme) reconstituted with

165 Pterin-free iNOS(heme) oxidizes NHA to citrulline, N(del

166 of 2 to 2.5 electron equiv, but reduction of pterin-free iNOS(heme) requires only 1 to 1.5 electron e

167 The reactivity of pterin-bound and pterin-free iNOS(heme) was examined, using sodium dithio

168 )B-bound FLiNOS and HDiNOS resembles that of pterin-free iNOS: the hydroxylation of arginine is very

169 phosphoryl-5-methyl-1-pyrroline N-oxide that pterin-free nNOS generates superoxide from the reductase

170 Pterin-free NOS exhibits a Soret band (416-420 nm) chara

171 Additionally, pterin-free NOS was reconstituted with 6-methylpterin an

172 Six protected cysteine residues in pterin-free NOS were identified by labeling of NOS with

173 Reconstitution of pterin-free NOS with H(4)B was monitored by a shift in t

174 ctron donor for the overall reaction) or the pterin, H2MPT (the electron acceptor for the overall rea

175 eractions with pterin and L-Arg suggest that pterin has electronic influences on heme-bound oxygen.

176 ow structural versus redox properties of the pterin impact on its multifaceted role in iNOS function.

177 Tetrahydromonapterin is a major pterin in Escherichia coli and is hypothesized to be the

178 ough GTP has been shown to be a precursor of pterins in archaea, homologues of GTPCHI have not been i

179 The first step in the biosynthesis of pterins in bacteria and plants is the conversion of GTP

180 at conformational differences cannot explain pterin inactivity.

181 ing the protonation of the bridged Fe(II)-OO-pterin intermediate in WT to productively form Fe(IV)=O,

182 mechanism via formation of a novel cationic pterin intermediate.

183 han tetrahydrobiopterin, suggesting that the pterin is a physiological reductant.

184 While pterin is a ubiquitous oxidative product of folate degra

185 reduction of O(2) to peroxide by Fe(II) and pterin is favored over individual one-electron reactions

186 sequently reacts with the Fe(II) site if the pterin is properly oriented for formation of an Fe-OO-pt

187 omatid parasites, reduction of such oxidized pterins is crucial for pterin and folate salvage.

188 ts show that the capacity to reduce oxidized pterins is not ubiquitous in folate-synthesizing organis

189 opterin, 6-formylpterin, 6-carboxypterin and pterin) is proposed: 1.5ml of an N2-flushed, alkaline (p

190 opterin, 6-hydroxymethylpterin, d-neopterin, pterin, isoxanthopterin, and xanthopterin, as well as cr

191 deal with the molybdenum prosthetic group (a pterin known as Moco); the biosynthesis of the "M-cluste

192 Pterin levels and enzyme activities fall on day 3 and pl

193 In the complex with LY309887, the pterin-like ring of the analogue stacks against the si f

194 ssentiality of pteridine reductase (PTR1) in pterin metabolism in the African trypanosome.

195 gy experiments, and Arad3529 deaminated many pterin metabolites (substrate, k(cat)/K(m) [M(-1) s(-1)]

196 4-diaminopyrimidine moiety from adopting the pterin mode of binding observed in dihydrofolate reducta

197 Together, the metal and the pterin moiety form the redox reactive molybdenum cofacto

198 The pterin moiety of the ligand docks in a semiopen pocket a

199 enzyme, and suggested a binding site for the pterin moiety present in precursor Z and molybdopterin.

200 and pterin, the fully oxidized forms of the pterin molecule, fail to block peroxynitrite- or NO2-ind

201 enzymes predicted to contain a metal binding pterin (MPT), with the metal being either molybdenum or

202 ectrometry based determination of 6 aromatic pterins (neopterin, hydroxymethylpterin, xanthopterin, 6

203 s a different co-substrate binding sequence (pterin + O(2) + L-tyr) than PAH (L-phe + pterin + O(2)).

204 ce (pterin + O(2) + L-tyr) than PAH (L-phe + pterin + O(2)).

205 ating that the requirement for fully reduced pterin occurs at a point in catalysis beyond heme iron r

206 elate of molybdenum or tungsten with a novel pterin, occurs in virtually all organisms including huma

207 minimal changes in conformation of the bound pterin or in its interactions with the protein as compar

208 Pools of the pterin oxidation end-product pterin-6-carboxylate are, l

209 Only two properties were found to depend on pterin oxidation state (i.e., they required fully reduce

210 e or stereochemistry and were independent of pterin oxidation state: pterin binding affinity, and its

211 lic pathway that produces a family of hybrid pterin-phenylpyruvate conjugates, which we named the col

212 The reduced pterin pi-stacking in these mutant structures, relative

213 ll permanently exit the metabolically active pterin pool.

214 ate to H2neopterin, a known precursor to the pterin portion of methanopterin.

215 he first intermediate in biosynthesis of the pterin portion of tetrahydromethanopterin (H(4)MPT), a C

216 Reduced pterins prevent neither the inhibition of TH activity no

217 atalyzed by MtDHNA generates three different pterin products, one of which is not produced by other w

218 Under these conditions, the rate of pterin radical decay was increased as monitored by EPR s

219 S, like iNOS, has the capacity to generate a pterin radical during Arg oxidation.

220 he rate of heme-dioxy reduction is linked to pterin radical formation and is sensitive to pterin stru

221 oduced when oxygen activation occurs without pterin radical formation.

222 ng and suggests a model involving a cationic pterin radical in the catalytic cycle.

223 the ferrous nitrosyl in the presence of the pterin radical intermediate.

224 (ii) A direct correlation exists between pterin radical stability and the speed of its formation

225 A pterin radical was not observed with 4-amino-H(4)B- or p

226 ndergoes a one-electron oxidation (to form a pterin radical), which is essential to its ability to su

227 of reduced H(4)B and destabilization of the pterin radical, consequently slowing electron transfer t

228 hat could separately quantify the flavin and pterin radicals that formed in NOS during the reaction.

229 by altering the electronic properties of the pterin rather than changing protein structure or interac

230 ta to evaluate the mechanism of the O(2) and pterin reactions in TH.

231 In addition to playing a catalytic role in pterin recycling in the cytoplasm, it plays a regulatory

232 Expression of a trypanosomatid pterin reductase (PTR1) enabled rescue of the mutant by

233 Tyr325 contributes to the positioning of the pterin ring and its dihydroxypropyl side chain by hydrop

234 ludes proton transfer to the N5 group of the pterin ring and poises the methyl group for reaction wit

235 is poised to stabilize a positively charged pterin ring and suggests a model involving a cationic pt

236 alysis shows that the glutamate tail and the pterin ring are the highly polarized regions of the subs

237 The pterin ring displaces Tyr80 and binds in the adenine poc

238 The methyl groups at C-7 and C-9 of the pterin ring distinguish MPT from all other pterin-contai

239 The pterin ring forms an aromatic pi-stacking interaction wi

240 n that allows Asp120 to hydrogen bond to the pterin ring in the folate complex but must move to an "o

241 In the complex with CH(3)-H(4)folate, the pterin ring is also stacked against FAD in an orientatio

242 dropteroate synthase, which suggest that the pterin ring is bound in the hydrophobic core of an alpha

243 In one of the binding sites, the pterin ring is turned around such that Asn-221 hydrogen

244 te the first evidence for protonation of the pterin ring of CH3-H4folate.

245 forms the binding surface against which the pterin ring of cofactor binds, misorientation of dUMP re

246 e only side chain that hydrogen bonds to the pterin ring of the cofactor, 5,10-methylene-5,6,7,8-tetr

247 nters the active site where it displaces the pterin ring of the THF product.

248 reduction can take place independent of the pterin ring oxidation state, indicating that the require

249 Third, no NAD(P)H-dependent pterin ring reduction was found in tissue extracts.

250 axis of the pore, with the nicotinamide and pterin ring systems approximately stacked at the center.

251 for several important hydrogen bonds to the pterin ring to be formed.

252 con esculentum) tissues, no reduction of the pterin ring was seen after 15 h, although reduction and

253 r molecule which hydrogen bonds to N3 of the pterin ring.

254 e it enforces the correct orientation of the pterin ring.

255 e94, which pack against the nicotinamide and pterin rings of the cofactor and substrate, respectively

256 e found that supplementation of BH4 (via the pterin salvage pathway with Sep) increased Akt/eNOS phos

257 egulatory regions near genes associated with pterin [sepiapterin reductase (SPR)] and carotenoid [bet

258 OSs correlate to different binding modes for pterin side chains.

259 r dihydropterins to elucidate how changes in pterin side-chain structure and ring oxidation state reg

260 ive properties were exclusively dependent on pterin side-chain structure or stereochemistry and were

261 Trp or a derivative thereof binds in the NOS pterin site, participates in Arg oxidation, and becomes

262 HPS inhibitors which specifically target the pterin site.

263 mined that show how the compounds engage the pterin site.

264 f inhibitors that target both the active and pterin sites of a bNOS and function as antimicrobials.

265 NOS inhibitor targeting both the active and pterin sites was potent and functioned as an antimicrobi

266 o conjugates of the parent compound, such as pterin-SMX and methyl salicylate-SMX conjugates.

267 ep of the mechanism is formation of a peroxy-pterin species, which subsequently reacts with the Fe(II

268 opterin, 6-formylpterin, 6-carboxypterin and pterin), spiked to charcoal-treated potato and Arabidops

269 interferences including the 6-biopterin and pterin structural analogs of neopterin as well as glucos

270 re we used 5-methyl-H(4)B to investigate how pterin structure influences radical formation and associ

271 pterin radical formation and is sensitive to pterin structure.

272 e oxidase in the course of reaction with the pterin substrate lumazine at 2.2 A resolution and of the

273 ransfer reducing equivalents from FMN to the pterin substrate.

274 d, however, were quite different for the two pterin substrates.

275 oline moiety binds in similar fashion to the pterin substrates/products and dominates interactions wi

276 This chemoenzymatic pterin synthesis can be applied to the efficient product

277 in biosynthesis, was a rate-limiting step in pterin synthesis in plants and, therefore, in folate syn

278 ahydrobiopterin with an inhibitor of de novo pterin synthesis resulted in a predominance of monomeric

279 ydrolase (GCH1), the rate-limiting enzyme in pterin synthesis, thereby elevating levels of biopterin.

280 cyclohydrolase I (folE) mutant, deficient in pterin synthesis, was rescued by dihydropterins but not

281 , our results show the presence of autocrine pterin synthesis/recycling in human hair follicle cells

282 In comparison to pterin that aerobically decays, the Angeli's salt treate

283 e (4Fe:4S) cluster of FOR via one of the two pterins that coordinate the tungsten, and ends at the (4

284 Biopterin and pterin, the fully oxidized forms of the pterin molecule,

285 k cat value decreases to 0.9 with the latter pterin; this is likely to be the intrinsic effect for ad

286 of nitrogenase, Mo is bound in proteins to a pterin, thus forming the molybdenum cofactor (Moco) at t

287 Molybdenum is bound to a unique pterin, thus forming the molybdenum cofactor (Moco), whi

288 Some procedures for the reduction of pterins to dihydropterins may produce undesirable tetrah

289 ribes a procedure for the rapid reduction of pterins to dihydropterins while minimizing tetrahydropte

290 r mutants, none showed evidence of folate or pterin transport activity, and only At2g32040 was isolat

291 ressed in E. coli or in Leishmania folate or pterin transporter mutants, none showed evidence of fola

292 al coordination chemistry, which we call the pterin twist hypothesis.

293 have peroxide added, or are performed with a pterin unable to generate a radical shows NO production

294 gle electron donor is unique among P450s and pterin utilizing proteins alike and adds to the complexi

295 on source, the resulting methyl group on the pterin was predominantly labeled with three deuteriums.

296 ant for catalysis and are thought to involve pterin were studied.

297 ssed in Escherichia coli, various methylated pterins were detected, consistent with MJ0619 catalyzing

298 king ranks and geometries, a set of modified pterins were suggested as candidate substrates for Arad3

299 ctures show decreased pi-stacking with bound pterin when the wild-type pi-stacking Trp457 position is

300 eductase that participates in the salvage of pterins, which are essential for parasite growth.