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Duraisamy R, Al-Shar'i NA, Chandrashekharappa S, Deb PK, Gleiser RM, Tratrat C, Chopra D, Muthukurpalya Bhojegowd MR, Thirumalai D, Morsy MA, Ibrahim YF, Mohanlall V, Venugopala KN. Synthesis, biological evaluation, and computational investigation of ethyl 2,4,6-trisubstituted-1,4-dihydropyrimidine-5-carboxylates as potential larvicidal agents against Anopheles arabiensis. J Biomol Struct Dyn 2024; 42:4016-4028. [PMID: 37259506 DOI: 10.1080/07391102.2023.2217929] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 05/18/2023] [Indexed: 06/02/2023]
Abstract
Malaria is one of the most known vector-borne diseases caused by female Anopheles mosquito bites. According to WHO, about 247 million cases of malaria and 619,000 deaths were estimated worldwide in 2021, of which 95% of the cases and 96% of deaths occurred in the African region. Sadly, about 80% of all malaria deaths were of children under five years old. Despite the availability of different insecticides used to control this disease, the emergence of drug-resistant mosquitoes threatens public health. This, in turn, highlighted the need for new larvicidal agents that are effective at different larval life stages. This study aimed to identify novel larvicidal agents. To this end, a series of ethyl 2,4,6-trisubstituted-1,4-dihydropyrimidine-5-carboxylates 8a-i was synthesized using a three-step chemical synthetic approach via a Biginelli reaction employed as a key step. All title compounds were screened against Anopheles arabiensis to determine their larvicidal activities. Among them, two derivatives, ethyl 2-((4-bromophenyl)amino)-4-(4-fluorophenyl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate 8b and ethyl 2-((4-bromo-2-cyanophenyl)amino)-4-(4-fluorophenyl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate 8f, showed the highest larvicidal activity, with mortality of 94% and 91%, respectively, and emerged as potential larvicidal agents. In addition, computational studies, including molecular docking and molecular dynamics simulations, were carried out to investigate their mechanism of action. The computational results showed that acetylcholinesterase appears to be a plausible molecular target for their larvicidal property.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Ramasamy Duraisamy
- Organic Synthesis and Nano-Bio Laboratory, Department of Chemistry, Thiruvalluvar University, Vellore, India
| | - Nizar A Al-Shar'i
- Department of Medicinal Chemistry and Pharmacognosy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Sandeep Chandrashekharappa
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER-R) Raebareli, Lucknow, UP, India
| | - Pran Kishore Deb
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Philadelphia University, Amman, Jordan
| | - Raquel M Gleiser
- CREAN-IMBIV (CONICET-UNC), Universidad Nacional de Cordoba, Cordoba, Argentina
| | - Christophe Tratrat
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Saudi Arabia
| | - Deepak Chopra
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal, Madhya Pradesh, India
| | | | - Dhakshanamurthy Thirumalai
- Organic Synthesis and Nano-Bio Laboratory, Department of Chemistry, Thiruvalluvar University, Vellore, India
| | - Mohamed A Morsy
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Saudi Arabia
- Department of Pharmacology, Faculty of Medicine, Minia University, El-Minia, Egypt
| | - Yasmine F Ibrahim
- Department of Pharmacology, Faculty of Medicine, Minia University, El-Minia, Egypt
- Department of Pathological Sciences, Fakeeh College for Medical Sciences, Jeddah, Saudi Arabia
| | - Viresh Mohanlall
- Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology, Durban, South Africa
| | - Katharigatta N Venugopala
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Saudi Arabia
- Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology, Durban, South Africa
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1,2,3-Triazolyl-tetrahydropyrimidine Conjugates as Potential Sterol Carrier Protein-2 Inhibitors: Larvicidal Activity against the Malaria Vector Anopheles arabiensis and In Silico Molecular Docking Study. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27092676. [PMID: 35566029 PMCID: PMC9102322 DOI: 10.3390/molecules27092676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/17/2022] [Accepted: 04/19/2022] [Indexed: 12/18/2022]
Abstract
Alteration of insect growth regulators by the action of inhibitors is becoming an attractive strategy to combat disease-transmitting insects. In the present study, we investigated the larvicidal effect of 1,2,3-triazolyl-pyrimidinone derivatives against the larvae of the mosquito Anopheles arabiensis, a vector of malaria. All compounds demonstrated insecticidal activity against mosquito larvae in a dose-dependent fashion. A preliminary study of the structure-activity relationship indicated that the electron-withdrawing substituent in the para position of the 4-phenyl-pyrimidinone moiety enhanced the molecules' potency. A docking study of these derivatives revealed favorable binding affinity for the sterol carrier protein-2 receptor, a protein present in the intestine of the mosquito larvae. Being effective insecticides against the malaria-transmitting Anopheles arabiensis, 1,2,3-triazole-based pyrimidinones represent a starting point to develop novel inhibitors of insect growth regulators.
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Venugopala KN, Ramachandra P, Tratrat C, Gleiser RM, Bhandary S, Chopra D, Morsy MA, Aldhubiab BE, Attimarad M, Nair AB, Sreeharsha N, Venugopala R, Deb PK, Chandrashekharappa S, Khalil HE, Alwassil OI, Abed SN, Bataineh YA, Palenge R, Haroun M, Pottathil S, Girish MB, Akrawi SH, Mohanlall V. Larvicidal Activities of 2-Aryl-2,3-Dihydroquinazolin -4-ones against Malaria Vector Anopheles arabiensis, In Silico ADMET Prediction and Molecular Target Investigation. Molecules 2020; 25:molecules25061316. [PMID: 32183140 PMCID: PMC7144721 DOI: 10.3390/molecules25061316] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 12/14/2022] Open
Abstract
Malaria, affecting all continents, remains one of the life-threatening diseases introduced by parasites that are transmitted to humans through the bites of infected Anopheles mosquitoes. Although insecticides are currently used to reduce malaria transmission, their safety concern for living systems, as well as the environment, is a growing problem. Therefore, the discovery of novel, less toxic, and environmentally safe molecules to effectively combat the control of these vectors is in high demand. In order to identify new potential larvicidal agents, a series of 2-aryl-1,2-dihydroquinazolin-4-one derivatives were synthesized and evaluated for their larvicidal activity against Anopheles arabiensis. The in silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of the compounds were also investigated and most of the derivatives possessed a favorable ADMET profile. Computational modeling studies of the title compounds demonstrated a favorable binding interaction against the acetylcholinesterase enzyme molecular target. Thus, 2-aryl-1,2-dihydroquinazolin-4-ones were identified as a novel class of Anopheles arabiensis insecticides which can be used as lead molecules for the further development of more potent and safer larvicidal agents for treating malaria.
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Affiliation(s)
- Katharigatta N. Venugopala
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
- Department of Biotechnology and Food Technology, Durban University of Technology, Durban 4001, South Africa;
- Correspondence:
| | - Pushpalatha Ramachandra
- Department of Chemistry, School of Applied Sciences, REVA University, Bangalore 560 064, India; (P.R.); (R.P.)
| | - Christophe Tratrat
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Raquel M. Gleiser
- CREAN-IMBIV (UNC-CONICET), Av. Valparaíso s.n., Córdoba, Argentina and FCEFyN, AV. Sarsfield 299, Universidad Nacional de Cordoba, Cordoba 5000, Argentina;
| | - Subhrajyoti Bhandary
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462 066, Madhya Pradesh, India; (S.B.); (D.C.)
| | - Deepak Chopra
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462 066, Madhya Pradesh, India; (S.B.); (D.C.)
| | - Mohamed A. Morsy
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
- Department of Pharmacology, Faculty of Medicine, Minia University, El-Minia 61511, Egypt
| | - Bandar E. Aldhubiab
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Mahesh Attimarad
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Anroop B. Nair
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Nagaraja Sreeharsha
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Rashmi Venugopala
- Department of Public Health Medicine, University of KwaZulu-Natal, Howard College Campus, Durban 4001, South Africa;
| | - Pran Kishore Deb
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Philadelphia University, P.O. Box 1, Amman 19392, Jordan; (P.K.D.); (S.N.A.); (Y.A.B.)
| | - Sandeep Chandrashekharappa
- Institute for Stem Cell Biology and Regenerative Medicine, NCBS, TIFR, GKVK, Bellary Road, Bangalore 560 065, India;
| | - Hany Ezzat Khalil
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
- Department of Pharmacognosy, Faculty of Pharmacy, Minia University, Minia 61519, Egypt
| | - Osama I. Alwassil
- Department of Pharmaceutical Sciences, College of Pharmacy, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia;
| | - Sara Nidal Abed
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Philadelphia University, P.O. Box 1, Amman 19392, Jordan; (P.K.D.); (S.N.A.); (Y.A.B.)
| | - Yazan A. Bataineh
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Philadelphia University, P.O. Box 1, Amman 19392, Jordan; (P.K.D.); (S.N.A.); (Y.A.B.)
| | - Ramachandra Palenge
- Department of Chemistry, School of Applied Sciences, REVA University, Bangalore 560 064, India; (P.R.); (R.P.)
| | - Michelyne Haroun
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Shinu Pottathil
- Department of Biomedical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Meravanige B. Girish
- Department of Biomedical Sciences, College of Medicine, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Sabah H. Akrawi
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia; (C.T.); (M.A.M.); (B.E.A.); (M.A.); (A.B.N.); (N.S.); (H.E.K.); (M.H.); (S.H.A.)
| | - Viresh Mohanlall
- Department of Biotechnology and Food Technology, Durban University of Technology, Durban 4001, South Africa;
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Oppenheim SJ, Rosenfeld JA, DeSalle R. Genome content analysis yields new insights into the relationship between the human malaria parasite Plasmodium falciparum and its anopheline vectors. BMC Genomics 2017; 18:205. [PMID: 28241792 PMCID: PMC5327517 DOI: 10.1186/s12864-017-3590-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 02/13/2017] [Indexed: 11/24/2022] Open
Abstract
Background The persistent and growing gap between the availability of sequenced genomes and the ability to assign functions to sequenced genes led us to explore ways to maximize the information content of automated annotation for studies of anopheline mosquitos. Specifically, we use genome content analysis of a large number of previously sequenced anopheline mosquitos to follow the loss and gain of protein families over the evolutionary history of this group. The importance of this endeavor lies in the potential for comparative genomic studies between Anopheles and closely related non-vector species to reveal ancestral genome content dynamics involved in vector competence. In addition, comparisons within Anopheles could identify genome content changes responsible for variation in the vectorial capacity of this family of important parasite vectors. Results The competence and capacity of P. falciparum vectors do not appear to be phylogenetically constrained within the Anophelinae. Instead, using ancestral reconstruction methods, we suggest that a previously unexamined component of vector biology, anopheline nucleotide metabolism, may contribute to the unique status of anophelines as P. falciparum vectors. While the fitness effects of nucleotide co-option by P. falciparum parasites on their anopheline hosts are not yet known, our results suggest that anopheline genome content may be responding to selection pressure from P. falciparum. Whether this response is defensive, in an attempt to redress improper nucleotide balance resulting from P. falciparum infection, or perhaps symbiotic, resulting from an as-yet-unknown mutualism between anophelines and P. falciparum, is an open question that deserves further study. Conclusions Clearly, there is a wealth of functional information to be gained from detailed manual genome annotation, yet the rapid increase in the number of available sequences means that most researchers will not have the time or resources to manually annotate all the sequence data they generate. We believe that efforts to maximize the amount of information obtained from automated annotation can help address the functional annotation deficit that most evolutionary biologists now face, and here demonstrate the value of such an approach. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3590-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sara J Oppenheim
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY, 10024, USA.
| | - Jeffrey A Rosenfeld
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY, 10024, USA.,Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ, USA
| | - Rob DeSalle
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY, 10024, USA
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Abstract
Microsporidia are obligate intracellular parasites whose genomes have been shaped by an extreme lifestyle. Specifically, their obligate intracellular parasitism has resulted in the loss of many genes and biochemical pathways, but these reductive processes have been often offset by the acquisition of several genes by means of horizontal gene transfer (HGT). Until recently, these HGTs were all found to have derived from prokaryotic donors, but a recent study suggests that some species took advantage of this mechanism to acquire one gene from an animal, which they maintained in their genome for metabolic purposes. The gene encodes for a purine nucleoside phosphorylase, and shows a strong phylogenetic signal of arthropod origin. Here, we briefly review our current knowledge of HGTs discovered across microsporidian genomes and discuss the implications of the most recent findings in this research area for understanding the origin and evolution of this highly adapted group of intracellular parasites. A novel gene potentially transferred by means of HGT to one microsporidia is also reported.
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Affiliation(s)
- Mohammed Selman
- Canadian Institute for Advanced Research; Department of Biology; University of Ottawa; Ottawa, ON Canada
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6
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Inhibition and structure of Toxoplasma gondii purine nucleoside phosphorylase. EUKARYOTIC CELL 2014; 13:572-9. [PMID: 24585883 DOI: 10.1128/ec.00308-13] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The intracellular pathogen Toxoplasma gondii is a purine auxotroph that relies on purine salvage for proliferation. We have optimized T. gondii purine nucleoside phosphorylase (TgPNP) stability and crystallized TgPNP with phosphate and immucillin-H, a transition-state analogue that has high affinity for the enzyme. Immucillin-H bound to TgPNP with a dissociation constant of 370 pM, the highest affinity of 11 immucillins selected to probe the catalytic site. The specificity for transition-state analogues indicated an early dissociative transition state for TgPNP. Compared to Plasmodium falciparum PNP, large substituents surrounding the 5'-hydroxyl group of inhibitors demonstrate reduced capacity for TgPNP inhibition. Catalytic discrimination against large 5' groups is consistent with the inability of TgPNP to catalyze the phosphorolysis of 5'-methylthioinosine to hypoxanthine. In contrast to mammalian PNP, the 2'-hydroxyl group is crucial for inhibitor binding in the catalytic site of TgPNP. This first crystal structure of TgPNP describes the basis for discrimination against 5'-methylthioinosine and similarly 5'-hydroxy-substituted immucillins; structural differences reflect the unique adaptations of purine salvage pathways of Apicomplexa.
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Hazleton KZ, Ho MC, Cassera MB, Clinch K, Crump DR, Rosario I, Merino EF, Almo SC, Tyler PC, Schramm VL. Acyclic immucillin phosphonates: second-generation inhibitors of Plasmodium falciparum hypoxanthine-guanine-xanthine phosphoribosyltransferase. CHEMISTRY & BIOLOGY 2012; 19:721-30. [PMID: 22726686 PMCID: PMC3397391 DOI: 10.1016/j.chembiol.2012.04.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 04/03/2012] [Accepted: 04/06/2012] [Indexed: 01/07/2023]
Abstract
Plasmodium falciparum, the primary cause of deaths from malaria, is a purine auxotroph and relies on hypoxanthine salvage from the host purine pool. Purine starvation as an antimalarial target has been validated by inhibition of purine nucleoside phosphorylase. Hypoxanthine depletion kills Plasmodium falciparum in cell culture and in Aotus monkey infections. Hypoxanthine-guanine-xanthine phosphoribosyltransferase (HGXPRT) from P. falciparum is required for hypoxanthine salvage by forming inosine 5'-monophosphate, a branchpoint for all purine nucleotide synthesis in the parasite. Here, we present a class of HGXPRT inhibitors, the acyclic immucillin phosphonates (AIPs), and cell permeable AIP prodrugs. The AIPs are simple, potent, selective, and biologically stable inhibitors. The AIP prodrugs block proliferation of cultured parasites by inhibiting the incorporation of hypoxanthine into the parasite nucleotide pool and validates HGXPRT as a target in malaria.
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Affiliation(s)
- Keith Z. Hazleton
- Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, USA
| | - Meng-Chiao Ho
- Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, USA
| | - Maria B. Cassera
- Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, USA
| | - Keith Clinch
- Carbohydrate Chemistry Group, Industrial Research Ltd., 69 Gracefield Road, Lower Hutt 5040, New Zealand
| | - Douglas R. Crump
- Carbohydrate Chemistry Group, Industrial Research Ltd., 69 Gracefield Road, Lower Hutt 5040, New Zealand
| | - Irving Rosario
- Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, USA
| | - Emilio F. Merino
- Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, USA
| | - Steve C. Almo
- Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, USA
| | - Peter C. Tyler
- Carbohydrate Chemistry Group, Industrial Research Ltd., 69 Gracefield Road, Lower Hutt 5040, New Zealand
| | - Vern L. Schramm
- Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, USA,, phone: 718-430-2814, fax: 718-430-8565
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8
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Cassera MB, Ho MC, Merino EF, Burgos ES, Rinaldo-Matthis A, Almo SC, Schramm VL. A high-affinity adenosine kinase from Anopheles gambiae. Biochemistry 2011; 50:1885-93. [PMID: 21247194 DOI: 10.1021/bi101921w] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Genome analysis revealed a mosquito orthologue of adenosine kinase in Anopheles gambiae (AgAK; the most important vector for the transmission of Plasmodium falciparum in Africa). P. falciparum are purine auxotrophs and do not express an adenosine kinase but rely on their hosts for purines. AgAK was kinetically characterized and found to have the highest affinity for adenosine (K(m) = 8.1 nM) of any known adenosine kinase. AgAK is specific for adenosine at the nucleoside site, but several nucleotide triphosphate phosphoryl donors are tolerated. The AgAK crystal structure with a bound bisubstrate analogue Ap(4)A (2.0 Å resolution) reveals interactions for adenosine and ATP and the geometry for phosphoryl transfer. The polyphosphate charge is partly neutralized by a bound Mg(2+) ion and an ion pair to a catalytic site Arg. The AgAK structure consists of a large catalytic core in a three-layer α/β/α sandwich, and a small cap domain in contact with adenosine. The specificity and tight binding for adenosine arise from hydrogen bond interactions of Asn14, Leu16, Leu40, Leu133, Leu168, Phe168, and Thr171 and the backbone of Ile39 and Phe168 with the adenine ring as well as through hydrogen bond interactions between Asp18, Gly64, and Asn68 and the ribosyl 2'- and 3'-hydroxyl groups. The structure is more similar to that of human adenosine kinase (48% identical) than to that of AK from Toxoplasma gondii (31% identical). With this extraordinary affinity for AgAK, adenosine is efficiently captured and converted to AMP at near the diffusion limit, suggesting an important role for this enzyme in the maintenance of the adenine nucleotide pool. mRNA analysis verifies that AgAK transcripts are produced in the adult insects.
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Affiliation(s)
- María B Cassera
- Department of Biochemistry, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461, United States
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Stütz AE, Wrodnigg TM. Imino sugars and glycosyl hydrolases: historical context, current aspects, emerging trends. Adv Carbohydr Chem Biochem 2011; 66:187-298. [PMID: 22123190 DOI: 10.1016/b978-0-12-385518-3.00004-3] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Forty years of discoveries and research on imino sugars, which are carbohydrate analogues having a basic nitrogen atom instead of oxygen in the sugar ring and, acting as potent glycosidase inhibitors, have made considerable impact on our contemporary understanding of glycosidases. Imino sugars have helped to elucidate the catalytic machinery of glycosidases and have refined our methods and concepts of utilizing them. A number of new aspects have emerged for employing imino sugars as pharmaceutical compounds, based on their profound effects on metabolic activities in which glycosidases are involved. From the digestion of starch to the fight against viral infections, from research into malignant diseases to potential improvements in hereditary storage disorders, glycosidase action and inhibition are essential issues. This account aims at combining general developments with a focus on some niches where imino sugars have become useful tools for glycochemistry and glycobiology.
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Affiliation(s)
- Arnold E Stütz
- Institut für Organische Chemie, Technische Universität Graz, Austria
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10
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Bao YY, Li BL, Liu ZB, Xue J, Zhu ZR, Cheng JA, Zhang CX. Triazophos up-regulated gene expression in the female brown planthopper, Nilaparvata lugens. JOURNAL OF INSECT PHYSIOLOGY 2010; 56:1087-1094. [PMID: 20223245 DOI: 10.1016/j.jinsphys.2010.03.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Revised: 03/01/2010] [Accepted: 03/02/2010] [Indexed: 05/28/2023]
Abstract
The widespread use of insecticides has caused the resurgence of the brown planthopper, Nilaparvata lugens, in Asia. In this study, we investigated an organo-phosphorous insecticide, triazophos, and its ability to induce gene expression variation in female N. lugens nymphs just before emergence. By using the suppression subtractive hybridization method, a triazophos-induced cDNA library was constructed. In total, 402 differentially expressed cDNA clones were obtained. Real-time qPCR analysis confirmed that triazophos up-regulated the expression of six candidate genes at the transcript level in nymphs on day 3 of the 5th instar. These genes encode N. lugens vitellogenin, bystin, multidrug resistance protein (MRP), purine nucleoside phosphorylase (PNP), pyrroline-5-carboxylate reductase (P5CR) and carboxylesterase. Our results imply that the up-regulation of these genes may be involved in the induction of N. lugens female reproduction or resistance to insecticides.
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Affiliation(s)
- Yan-Yuan Bao
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou, China
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11
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Chaikuad A, Brady RL. Conservation of structure and activity in Plasmodium purine nucleoside phosphorylases. BMC STRUCTURAL BIOLOGY 2009; 9:42. [PMID: 19575810 PMCID: PMC2721837 DOI: 10.1186/1472-6807-9-42] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Accepted: 07/03/2009] [Indexed: 11/10/2022]
Abstract
BACKGROUND Purine nucleoside phosphorylase (PNP) is central to purine salvage mechanisms in Plasmodium parasites, the causative agents of malaria. Most human malaria results from infection either by Plasmodium falciparum (Pf), the deadliest form of the parasite, or by the widespread Plasmodium vivax (Pv). Whereas the PNP enzyme from Pf has previously been studied in detail, despite the prevalence of Pv little is known about many of the key metabolic enzymes from this parasite, including PvPNP. RESULTS The crystal structure of PvPNP is described and is seen to have many features in common with the previously reported structure of PfPNP. In particular, the composition and conformations of the active site regions are virtually identical. The crystal structure of a complex of PfPNP co-crystallised with inosine and arsenate is also described, and is found to contain a mixture of products and reactants - hypoxanthine, ribose and arsenate. The ribose C1' in this hybrid complex lies close to the expected point of symmetry along the PNP reaction coordinate, consistent with a conformation between the transition and product states. These two Plasmodium PNP structures confirm the similarity of structure and mechanism of these enzymes, which are also confirmed in enzyme kinetic assays using an array of substrates. These reveal an unusual form of substrate activation by 2'-deoxyinosine of PvPNP, but not PfPNP. CONCLUSION The close similarity of the Pf and Pv PNP structures allows characteristic features to be identified that differentiate the Apicomplexa PNPs from the human host enzyme. This similarity also suggests there should be a high level of cross-reactivity for compounds designed to inhibit either of these molecular targets. However, despite these similarities, there are also small differences in the activities of the two Plasmodium enzymes.
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Affiliation(s)
- Apirat Chaikuad
- Department of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK.
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