25104-12-5Relevant articles and documents
Crystal structure of arginase from plasmodium falciparum and implications for l -arginine depletion in malarial infection
Dowling, Daniel P.,Ilies, Monica,Olszewski, Kellen L.,Portugal, Silvia,Mota, Maria M.,Llinas, Manuel,Christianson, David W.
, p. 5600 - 5608 (2010)
The 2.15 A resolution crystal structure of arginase from Plasmodium falciparum, the parasite that causes cerebral malaria, is reported in complex with the boronic acid inhibitor 2(S)-amino-6-boronohexanoic acid (ABH) (K d = 11 μM). This is the first crystal structure of a parasitic arginase. Various protein constructs were explored to identify an optimally active enzyme form for inhibition and structural studies and to probe the structure and function of two polypeptide insertions unique to malarial arginase: a 74-residue low-complexity region contained in loop L2 and an 11-residue segment contained in loop L8. Structural studies indicate that the low-complexity region is largely disordered and is oriented away from the trimer interface; its deletion does not significantly compromise enzyme activity. The loop L8 insertion is located at the trimer interface and makes several intra- and intermolecular interactions important for enzyme function. In addition, we also demonstrate that arg- Plasmodium berghei sporozoites show significantly decreased liver infectivity in vivo. Therefore, inhibition of malarial arginase may serve as a possible candidate for antimalarial therapy against liver-stage infection, and ABH may serve as a lead for the development of inhibitors.
Cyclic dipeptide of D-ornithine obtained from the dobsonfly, Protohermes grandis thunberg
Tanaka, Ryuichiro,Oda, Masashi
, p. 1669 - 1670 (2009)
A new compound was isolated from the water-soluble fraction of a methyl alcohol extract obtained from the larva of the dobsonfly (Protohermes grandis Thunberg). The novel compound had a 12-membered ring and was confirmed to be a cyclic dipeptide of D-orni
Stabilized and immobilized bacillus subtilis arginase for the biobased production of nitrogen-containing chemicals
Koenst, Paul M.,Turras, Pedro M. C. C. D.,Franssen, Maurice C. R.,Scott, Elinor L.,Sanders, Johan P. M.
, p. 1493 - 1502 (2010)
L-Ornithine could serve as an intermediate in the biobased production of 1,4-diaminobutane from L-arginine. Using the concept of biorefinery, Larginine could become widely available from biomass waste streams via the nitrogen storage polypeptide cyanophycin. Selective hydrolysis of L-arginine to L-ornithine is difficult to perform chemically, therefore the stabilization and immobilization of Bacillus subtilis arginase (EC 3.5.3.1) was studied in a continuously stirred membrane reactor system. Initial pH of the substrate solution, addition of L-aspartic acid and reducing agents all appeared to have an effect on the operational stability of B. subtilis arginase. A remarkably good operational stability (total turnover number, TTN = 1. 13-108) at the pH of arginine free base (pH 11.0) was observed, which was further improved with the addition of sodium dithionite to the substrate solution (TTN > 1.109). B. subtilis arginase was successfully immobilized on three commercially available epoxy-activated supports. Immobilization on Sepabeads EC-EP was most promising, resulting in a recovered activity of 75% and enhanced thermostability. In conclusion, the stabilization and immobilization of B. subtilis arginase has opened up possibilities for its application in the biobased production of nitrogen-containing chemicals as an alternative to the petrochemical production.
Structure and function of non-native metal clusters in human arginase i
D'Antonio, Edward L.,Hai, Yang,Christianson, David W.
, p. 8399 - 8409,11 (2012)
Various binuclear metal ion clusters and complexes have been reconstituted in crystalline human arginase I by removing the Mn2+2 cluster of the wild-type enzyme with metal chelators and subsequently soaking the crystalline apoenzyme in buffer solutions containing NiCl2 or ZnCl2. X-ray crystal structures of these metal ion variants are correlated with catalytic activity measurements that reveal differences resulting from metal ion substitution. Additionally, treatment of crystalline Mn2+2-human arginase I with Zn2+ reveals for the first time the structural basis for inhibition by Zn2+, which forms a carboxylate-histidine-Zn2+ triad with H141 and E277. The imidazole side chain of H141 is known to be hyper-reactive, and its chemical modification or mutagenesis is known to similarly compromise catalysis. The reactive substrate analogue 2(S)-amino-6-boronohexanoic acid (ABH) binds as a tetrahedral boronate anion to Mn2+2, Co2+ 2, Ni2+2, and Zn2+2 clusters in human arginase I, and it can be stabilized by a third inhibitory Zn2+ ion coordinated by H141. Because ABH binds as an analogue of the tetrahedral intermediate and its flanking transition states in catalysis, this implies that the various metallo-substituted enzymes are capable of some level of catalysis with an actual substrate. Accordingly, we establish the following trend for turnover number (kcat) and catalytic efficiency (k cat/KM): Mn2+ > Ni2+ ≈ Co 2+ ? Zn2+. Therefore, Mn2+ is required for optimal catalysis by human arginase I.
Molecular insights into the biosynthesis of guadinomine: A type III secretion system inhibitor
Holmes, Tracy C.,May, Aaron E.,Zaleta-Rivera, Kathia,Ruby, J. Graham,Skewes-Cox, Peter,Fischbach, Michael A.,Derisi, Joseph L.,Iwatsuki, Masato,Omura, Satoshi,Khosla, Chaitan
, p. 17797 - 17806 (2012)
Guadinomines are a recently discovered family of anti-infective compounds produced by Streptomyces sp. K01-0509 with a novel mode of action. With an IC50 of 14 nM, guadinomine B is the most potent known inhibitor of the type III secretion system (TTSS) of Gram-negative bacteria. TTSS activity is required for the virulence of many pathogenic Gram-negative bacteria including Escherichia coli, Salmonella spp., Yersinia spp., Chlamydia spp., Vibrio spp., and Pseudomonas spp. The guadinomine (gdn) biosynthetic gene cluster has been cloned and sequenced and includes 26 open reading frames spanning 51.2 kb. It encodes a chimeric multimodular polyketide synthase, a nonribosomal peptide synthetase, along with enzymes responsible for the biosynthesis of the unusual aminomalonyl-acyl carrier protein extender unit and the signature carbamoylated cyclic guanidine. Its identity was established by targeted disruption of the gene cluster as well as by heterologous expression and analysis of key enzymes in the biosynthetic pathway. Identifying the guadinomine gene cluster provides critical insight into the biosynthesis of these scarce but potentially important natural products.
Kinetic Behavior of L-Arginine in the Interlamellar Layer of Montmorillonite in Aqueous Suspension
Ikeda, Tetsuya,Yasunaga, Tatsuya
, p. 1253 - 1257 (1984)
Two relaxations were found in aqueous suspensions of montmorillonite containing L-arginine by using the pressure-jump relaxation method with electric conductivity detection.It was found that L-arginine intercalates into the interlamellar layer and is hydrolyzed slighlty into ornithine and urea.Some plausible mechanism were examined by using kinetic and static experimental results, and fast and slow relaxations observed were attributed to the intercalation of L-arginine into the interlamellar layer and the hydrolysis of the intercalated L-arginine in the interlamellar layer of the montmorillonite, respectively.The forward and backward rate constants of the former process were determined to be 8.5 X 1E4 mol-1dm3s-1 and 5.8 X 1E2 s-1, and the forward and backward rate constants of the latter process 2.0 X 1E2 and 2.2 X 1E2 s-1, respectively at 25 deg C.The experimental results showed that the equilibrium constant of the overall reaction obtained kinetically was in good agreement with that obtained from the adsorption isotherm, and that the ornithine- or urea-releasing reaction in the proposed mechanism was the rate-determing step, i.e.
Daryamide Analogues from a Marine-Derived Streptomyces species
Fu, Peng,La, Scott,MacMillan, John B.
, p. 1096 - 1101 (2017)
Three new cyclohexene amine derivatives, daryamides D-F (1-3), a new arylamine derivative, carpatamide D (4), and a new ornithine lactamization derivative, ornilactam A (5), were isolated from the marine-derived Streptomyces strain SNE-011. Their structures, including absolute configurations, were elucidated on the basis of spectroscopic analysis and chemical methods. The carpatamide skeleton could be considered as the biosynthetic precursor of the daryamides.
A new ureido-substituted amino acid from the tubers of Gymnadenia conopsea
Lin, Peng-Cheng,Yao, Jing,Wu, Jiang,Tian, Jin,Bao, Yi,Lin, Sheng
, p. 257 - 259 (2017)
A new ureido-substituted amino acid, conopsamide A (1), has been isolated from an ethanolic extract of the tubers of Gymnadenia conopsea. Its structure was elucidated by extensive spectroscopic analysis, and the absolute configuration was assigned by Marfey's method. The new compound was evaluated for in vitro assay for HDAC1 (Histone Deacetylase 1) inhibitory activity.
Thermokinetic studies on the activation of arginase by glycine
Xie, Xiuyin,Wang, Cunxin,Wang, Zhiyong
, p. 928 - 932 (2010)
The activation of bovine liver arginase, which catalyzes the hydrolysis of L-arginine to L-ornithine and urea, by glycine was studied by thermokinetic methods at 37 °C in 40 mmol?L-1 sodium barbiturate-HCl buffer solution (pH 9.4). Results of this experiment indicate that an appropriate concentration of glycine can enhance the activity of arginase, and the relative activation rate reached its maximum value, 74%, when the concentration of glycine in reaction system was 1 mmol?L-1 and the initial concentration of arginine was 5 mmol?L-1. With the increase of substrate concentration, the relative activation rate decreased in a definite glycine concentration. Michealis constant Km of reaction decreased from 5.53 to 3.31 mmol?L-1 and inhibition constant of product L-ornithine Kp increased from 1.18 to 3.73 mmol?L-1 when glycine concentration was 1 mmol?L-1. For these reasons one possible activation mechanism of arginase by glycine was suggested that the activation effect results from the competition of glycine and arginine to enzyme activity position. When one or two of the activity positions of arginase are occupied by glycine, it is propitious for the enzyme to complex with substrate and obstruct L-ornithine from combining with enzyme, and when all of the activity positions are occupied by glycine, the activation effect vanishs and the inhibition effect appears.
Developing an irreversible inhibitor of human DDAH-1, an enzyme upregulated in melanoma
Wang, Yun,Hu, Shougang,Gabisi Jr., Abdul M.,Er, Joyce A. V.,Pope, Arthur,Burstein, Gayle,Schardon, Christopher L.,Cardounel, Arturo J.,Ekmekcioglu, Suhendan,Fast, Walter
, p. 792 - 797 (2014)
Inhibitors of the human enzyme dimethylarginine dimethylaminohydrolase-1 (DDAH-1) can raise endogenous levels of asymmetric dimethylarginine (ADMA) and lead to a subsequent inhibition of nitric oxide synthesis. In this study, N 5-(1-imino-2-chloroethyl)-L-ornithine (Cl-NIO) is shown to be a potent time- and concentration-dependent inhibitor of purified human DDAH-1 (KI=1.3±0.6 μM; kinact=0.34±0.07 min -1), with >500-fold selectivity against two arginine-handling enzymes in the same pathway. An activity probe is used to measure the in cell IC50 value (6.6±0.2 μM) for Cl-NIO inhibition of DDAH-1 artificially expressed within cultured HEK293T cells. A screen of diverse melanoma cell lines reveals that a striking 50/64 (78 %) of melanoma lines tested showed increased levels of DDAH-1 relative to normal melanocyte control lines. Treatment of the melanoma A375 cell line with Cl-NIO shows a subsequent decrease in cellular nitric oxide production. Cl-NIO is a promising tool for the study of methylarginine-mediated nitric oxide control and a potential therapeutic lead compound for other indications with elevated nitric oxide production, such as septic shock and idiopathic pulmonary fibrosis. Inactivator of DDAH-1: The enzyme DDAH-1 regulates nitric oxide production by catabolizing endogenous inhibitors of nitric oxide synthases. Here, we develop a potent irreversible inactivator of DDAH-1 and demonstrate its use with purified enzymes, with DDAH-1 artificially expressed in cultured cells, and with DDAH-1 that we found to be overexpressed in ～80 % of cultured melanoma cell lines tested.
