553-12-8Relevant articles and documents
A point mutation of valine-311 to methionine in Bacillus subtilis protoporphyrinogen oxidase does not greatly increase resistance to the diphenyl ether herbicide oxyfluorfen
Jeong, Eunjoo,Houn, Thavrak,Kuk, Yongin,Kim, Eun-Seon,Chandru, Hema Kumar,Baik, Myunggi,Back, Kyoungwhan,Guh, Ja-Ock,Han, Oksoo
, p. 389 - 397 (2003)
In an effort to asses the effect of Val311Met point mutation of Bacillus subtilis protoporphyrinogen oxidase on the resistance to diphenyl ether herbicides, a Val311Met point mutant of B. subtilis protoporphyrinogen oxidase was prepared, heterologously expressed in Escherichia coli, and the purified recombinant Val311Met mutant protoporphyrinogen oxidase was kinetically characterized. The mutant protoporphyrinogen oxidase showed very similar kinetic patterns to wild type protoporphyrinogen oxidase, with slightly decreased activity dependent on pH and the concentrations of NaCl, Tween 20, and imidazole. When oxyfluorfen was used as a competitive inhibitor, the Val311Met mutant protoporphyrinogen oxidase showed an increased inhibition constant about 1.5 times that of wild type protoporphyrinogen oxidase. The marginal increase of the inhibition constant indicates that the Val311Met point mutation in B. subtilis protoporphyrinogen oxidase may not be an important determinant in the mechanism that protects protoporphyrinogen oxidase against diphenyl ether herbicides.
On the identification of hemin formed ennzymatically from protoporphyrin and iron.
SCHAEFER,SCHMIDTMANN,WEINER
, p. 269 - 271 (1962)
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On the Nature of 'Haematoporphyrin Derivative'
Bonnett, Raymond,Ridge, Richard J.,Scourides, Panayiotis A.,Berenbaum, Morris C.
, p. 3135 - 3140 (1981)
The components of haematoporphyrin derivative ( a preparation used as a photosensitiser in clinical applications, and made by treating haematoporphyrin with sulphuric acid-acetic acid) have been separated by preparative h.p.l.c. and identified by comparison with authentic porphyrincarboxylic acids.The composition of the mixture is somewhat variable but the main components are O,O'-diacetylhaematoporphyrin (6) and O-acetylhaematoporphyrin (2)/(3) with smaller amounts of the 8(3)-(1-acetoxyethyl)-3(8)-vinyldeuteroporphyrin isomers (7) and (8) and the corresponding alcohols (4) and (5).
Quantitative structural insight into human variegate porphyria disease
Wang, Baifan,Wen, Xin,Qin, Xiaohong,Wang, Zhifang,Tan, Ying,Shen, Yuequan,Xi, Zhen
, p. 11731 - 11740 (2013)
Defects in the human protoporphyrinogen oxidase (hPPO) gene, resulting in ～ 50% decreased activity of hPPO, is responsible for the dominantly inherited disorder variegate porphyria (VP). To understand the molecular mechanism of VP, we employed the sitedirected mutagenesis, biochemical assays, structural biology, and molecular dynamics simulation studies to investigate VP-causing hPPO mutants. We report here the crystal structures of R59Q and R59G mutants in complex with acifluorfen at a resolution of 2.6 and 2.8 A. The r.m.s.d. of the Cα atoms of the active site structure of R59G and R59Q with respect to the wild-type was 0.20 and 0.15 A, respectively. However, these highly similar static crystal structures of mutants with the wild-type could not quantitatively explain the observed large differences in their enzymatic activity. To understand how the hPPO mutations affect their catalytic activities, we combined molecular dynamics simulation and statistical analysis to quantitatively understand the molecular mechanism of VP-causing mutants. We have found that the probability of the privileged conformations of hPPO can be correlated very well with the kcat/Km of PPO (correlation coefficient, R2 > 0.9), and the catalytic activity of 44 clinically reported VP-causing mutants can be accurately predicted. These results indicated that the VP-causing mutation affect the catalytic activity of hPPO by affecting the ability of hPPO to sample the privileged conformations. The current work, together with our previous crystal structure study on the wild-type hPPO, provided the quantitative structural insight into human variegate porphyria disease.
ROMP polymer supported manganese porphyrins: Influence of C[dbnd]C bonds along polymer chains on catalytic behavior in oxidation of low concentration Fe2+
Li, Fanfan,Wang, Xuan,Zhang, Yanwu,Zhao, Huanhuan
, (2020/02/22)
One unsaturated polymer support was prepared through ring opening metathesis polymerization (ROMP) of norbornene-2,3-dip-toluene sulfonate initiated by Grubbs 2nd initiator and manganese porphyrins were immobilized on polymer through transesterification reaction. To investigate the effect of C[dbnd]C bonds along polymer chains on the catalytic behavior, the obtained polymer supported catalyst (P-PPIXMnCl) was applied in oxidation of low concentration Fe2+ to mimic catalytic behavior of Ceruloplasmin. In the presence of P-PPIXMnCl, the conversion of Fe2+ reaches to 91.92% and 96.46% at 10 °C and 37.5 °C (body temperature), respectively. Compared to manganese porphyrins, P-PPIXMnCl can dramatically increase oxidation rate of Fe2+ and the catalytic kinetic shows that the oxidation reaction changes from second-order to third-order. Upon hydrogenation of ROMP polymer, the oxidation reaction still conforms to the second-order kinetics. Density functional theory (DFT) calculation shows that the C[dbnd]C bonds along polymer chains play an important role in the coordination with Fe2+ in the catalytic microenvironment. The real time morphology of supported catalysts in aqueous environment characterized by Cryo-TEM indicates that hydrogenation can shrink the morphology of polymer-water skeleton. The catalyst could be recycled six times without any significant loss in activity. The liner heterogeneous catalyst is expected to be used as drugs for treating excessive iron accumulation in the human body.
Revisiting the Mechanism of the Anaerobic Coproporphyrinogen III Oxidase HemN
Ji, Xinjian,Mo, Tianlu,Liu, Wan-Qiu,Ding, Wei,Deng, Zixin,Zhang, Qi
, p. 6235 - 6238 (2019/04/04)
HemN is a radical S-adenosyl-l-methionine (SAM) enzyme that catalyzes the oxidative decarboxylation of coproporphyrinogen III to produce protoporphyrinogen IX, an intermediate in heme biosynthesis. HemN binds two SAM molecules in the active site, but how these two SAMs are utilized for the sequential decarboxylation of the two propionate groups of coproporphyrinogen III remains largely elusive. Provided here is evidence showing that in HemN catalysis a SAM serves as a hydrogen relay which mediates a radical-based hydrogen transfer from the propionate to the 5′-deoxyadenosyl (dAdo) radical generated from another SAM in the active site. Also observed was an unexpected shunt product resulting from trapping of the SAM-based methylene radical by the vinyl moiety of the mono-decarboxylated intermediate, harderoporphyrinogen. These results suggest a major revision of the HemN mechanism and reveal a new paradigm of the radical-mediated hydrogen transfer in radical SAM enzymology.
Preparation method of protoporphyrin disodium
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Paragraph 0063-0082, (2018/11/22)
The invention provides a preparation method of protoporphyrin disodium, and belongs to the field of synthesis of organic compounds. The method comprises the following steps: ensuring that protoporphyrin, absolute methanol and concentrated sulfuric acid are subjected to alcohol acid reaction in an ultrasound condition, so as to obtain protoporphyrin diester; ensuring that the protoporphyrin diester, a NaOH methanol solution and methylbenzene are subjected to saponification reaction in an ultrasound condition, so as to obtain the protoporphyrin disodium. The method has the advantages that assistance of ultrasonic wave is adopted to replace high-temperature reflux, so as to form the protoporphyrin disodium, hydrogen chloride gas is not required to be prepared during preparation, the adoptionof strong-toxicity reagents, such as chloroform, is further avoided, a high-temperature condition is not required to be use, the technology is simplified, and the whole process is easy to operate.
