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Pająk M. Methylated derivatives of l-tyrosine in reaction catalyzed by l-amino acid oxidase: isotope and inhibitory effects. J Biochem 2020; 168:509-514. [PMID: 32569353 DOI: 10.1093/jb/mvaa066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 06/10/2020] [Indexed: 11/14/2022] Open
Abstract
l-Amino acid oxidase (LAAO) is widely distributed in nature and shows important biological activity. It induces cell apoptosis and has antibacterial properties. This study was designed to investigate the effect of methyl substituent on its activity as methylated derivatives of l-tyrosine, labelled with short-lived B+ emitters, have been used in oncological diagnostics. To study isotope effects in the oxidative deamination of O-methyl-l-tyrosine, the deuterated isotopomer, i.e. O-methyl-[2-2H]-l-tyrosine, was synthesized by isotope exchange, catalyzed enzymatically by tryptophanase. Isotope effects were determined using the spectrophotometric non-competitive method. The values of isotope effects indicate that the α-C-H bond cleavage occurs in the rate determining step of the investigated reaction and α-hydrogen plays a role in the substrate binding process at the enzyme active site. The inhibitory effect on LAAO activity was studied with α-methyl-l-tyrosine and N-methyl-l-tyrosine. The mode of inhibition was determined based on Lineweavear-Burk plots intersections. α-Methyl-l-tyrosine has been found a mixed type inhibitor of the investigated enzyme, whereas N-methyl-l-tyrosine is a non-competitive inhibitor of LAAO.
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Affiliation(s)
- Małgorzata Pająk
- Faculty of Chemistry, University of Warsaw, Pasteur 1 Str, 02-093 Warsaw, Poland
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Yu Z, Yang Y, Wang Y, Yin J, Qiu J. Reactive oxygen species-scavenging system is involved in l-amino acid oxidase accumulation in Pseudoalteromonas sp. B3. 3 Biotech 2017; 7:326. [PMID: 28955623 DOI: 10.1007/s13205-017-0976-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 09/12/2017] [Indexed: 11/26/2022] Open
Abstract
To date, the mechanisms underlying the flavoprotein l-amino acid oxidase (LAAO) accumulation in cells remain unclear. In this study, using LAAO-producer Pseudoalteromonas spp. as model organisms, we found that the cell biomass is negatively associated with LAAO accumulation, whereas the LAAO accumulation is positively associated with the reactive oxygen species (ROS)-scavenging capability. The expression levels of ROS-scavenging-associated genes were up-regulated with LAAO accumulation in Pseudoalteromonas cells, which is presumably due to the requirement for the removal of LAAO-induced ROS. Exogenous H2O2 exposure experiment supported that the ROS-scavenging system is associated with LAAO accumulation in Pseudoalteromonas. All these observations indicate that ROS-scavenging capacity determines LAAO accumulation in bacterial cells. Our results shed a light on understanding the mechanism underlying controlling and adapting to LAAO accumulation in Pseudoalteromonas. Besides, our findings are critical to the improvement of heterologous expression of active LAAO in the future.
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Affiliation(s)
- Zhiliang Yu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
| | - Yanyan Yang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
| | - Yangsheng Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
| | - Jianhua Yin
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
| | - Juanping Qiu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
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3
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Higher fungi are a rich source of L-amino acid oxidases. 3 Biotech 2017; 7:230. [PMID: 28685478 DOI: 10.1007/s13205-017-0813-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 04/11/2017] [Indexed: 10/19/2022] Open
Abstract
L-Amino acid oxidases (LAO) are widely distributed enzymes but those from snake venoms have been studied the most. We describe a method for in-gel detection of LAO activities based on H2O2 detection by a horseradish peroxidase-coupled reaction using o-phenylenediamine. Complex substrates and single L-amino acids were used successfully for screening LAO activities in higher fungi using crude aqueous extracts of fruiting bodies of 22 basidiomycetes and 1 ascomycete. Half of these samples exhibited one to two bands of LAO activities with mostly broad substrate specificities and a variety of apparent molecular masses ranging from 25 to 200 kDa that were generally more active at pH 5.5 than at pH 8.0. Mushrooms are shown to be a rich source of LAOs that could find use in various medical and biotechnological applications.
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de Queiroz MR, de Sousa BB, da Cunha Pereira DF, Mamede CCN, Matias MS, de Morais NCG, de Oliveira Costa J, de Oliveira F. The role of platelets in hemostasis and the effects of snake venom toxins on platelet function. Toxicon 2017; 133:33-47. [PMID: 28435120 DOI: 10.1016/j.toxicon.2017.04.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 04/12/2017] [Accepted: 04/19/2017] [Indexed: 12/09/2022]
Abstract
The human body has a set of physiological processes, known as hemostasis, which keeps the blood fluid and free of clots in normal vessels; in the case of vascular injury, this process induces the local formation of a hemostatic plug, preventing hemorrhage. The hemostatic system in humans presents complex physiological interactions that involve platelets, plasma proteins, endothelial and subendothelial structures. Disequilibrium in the regulatory mechanisms that control the growth and the size of the thrombus is one of the factors that favors the development of diseases related to vascular disorders such as myocardial infarction and stroke, which are among the leading causes of death in the western world. Interfering with platelet function is a strategy for the treatment of thrombotic diseases. Antiplatelet drugs are used mainly in cases related to arterial thrombosis and interfere in the formation of the platelet plug by different mechanisms. Aspirin (acetylsalicylic acid) is the oldest and most widely used antithrombotic drug. Although highly effective in most cases, aspirin has limitations compared to other drugs used in the treatment of homeostatic disorders. For this reason, research related to molecules that interfere with platelet aggregation are of great relevance. In this regard, snake venoms are known to contain a number of molecules that interfere with hemostasis, including platelet function. The mechanisms by which snake venom components inhibit or activate platelet aggregation are varied and can be used as tools for the diagnosis and the treatment of several hemostatic disorders. The aim of this review is to present the role of platelets in hemostasis and the mechanisms by which snake venom toxins interfere with platelet function.
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Affiliation(s)
- Mayara Ribeiro de Queiroz
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica (N-Biofar), Belo Horizonte, MG, Brazil
| | - Bruna Barbosa de Sousa
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica (N-Biofar), Belo Horizonte, MG, Brazil
| | | | - Carla Cristine Neves Mamede
- Instituto de Ciências Agrárias, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica (N-Biofar), Belo Horizonte, MG, Brazil
| | - Mariana Santos Matias
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | | | - Júnia de Oliveira Costa
- Instituto Federal de Educação, Ciência e Tecnologia do Triângulo Mineiro, Ituiutaba, MG, Brazil
| | - Fábio de Oliveira
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica (N-Biofar), Belo Horizonte, MG, Brazil.
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5
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Guo C, Liu S, Dong P, Zhao D, Wang C, Tao Z, Sun MZ. Akbu-LAAO exhibits potent anti-tumor activity to HepG2 cells partially through produced H2O2 via TGF-β signal pathway. Sci Rep 2015; 5:18215. [PMID: 26655928 PMCID: PMC4677388 DOI: 10.1038/srep18215] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/16/2015] [Indexed: 02/07/2023] Open
Abstract
Previously, we characterized the biological properties of Akbu-LAAO, a novel L-amino acid oxidase from Agkistrodon blomhoffii ussurensis snake venom (SV). Current work investigated its in vitro anti-tumor activity and underlying mechanism on HepG2 cells. Akbu-LAAO inhibited HepG2 growth time and dose-dependently with an IC50 of ~38.82 μg/mL. It could induce the apoptosis of HepG2 cells. Akbu-LAAO exhibited cytotoxicity by inhibiting growth and inducing apoptosis of HepG2 as it showed no effect on its cell cycle. The inhibition of Akbu-LAAO to HepG2 growth partially relied on enzymatic-released H2O2 as catalase only partially antagonized this effect. cDNA microarray results indicated TGF-β signaling pathway was linked to the cytotoxicity of Akbu-LAAO on HepG2. TGF-β pathway related molecules CYR61, p53, GDF15, TOB1, BTG2, BMP2, BMP6, SMAD9, JUN, JUNB, LOX, CCND1, CDK6, GADD45A, CDKN1A were deregulated in HepG2 following Akbu-LAAO stimulation. The presence of catalase only slightly restored the mRNA changes induced by Akbu-LAAO for differentially expressed genes. Meanwhile, LDN-193189, a TGF-β pathway inhibitor reduced Akbu-LAAO cytotoxicity on HepG2. Collectively, we reported, for the first time, SV-LAAO showed anti-tumor cell activity via TGF-β pathway. It provides new insight of SV-LAAO exhibiting anti-tumor effect via a novel signaling pathway.
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Affiliation(s)
- Chunmei Guo
- Department of Biotechnology, Dalian Medical University, Dalian, Liaoning, 116044, China
| | - Shuqing Liu
- Department of Biochemistry, Dalian Medical University, Dalian, Liaoning, 116044, China
| | - Panpan Dong
- Department of Biotechnology, Dalian Medical University, Dalian, Liaoning, 116044, China.,Department of Biochemistry, Dalian Medical University, Dalian, Liaoning, 116044, China
| | - Dongting Zhao
- Department of Biotechnology, Dalian Medical University, Dalian, Liaoning, 116044, China.,Department of Biochemistry, Dalian Medical University, Dalian, Liaoning, 116044, China
| | - Chengyi Wang
- Department of Biotechnology, Dalian Medical University, Dalian, Liaoning, 116044, China.,Department of Biochemistry, Dalian Medical University, Dalian, Liaoning, 116044, China
| | - Zhiwei Tao
- Department of Biotechnology, Dalian Medical University, Dalian, Liaoning, 116044, China.,Department of Biochemistry, Dalian Medical University, Dalian, Liaoning, 116044, China
| | - Ming-Zhong Sun
- Department of Biotechnology, Dalian Medical University, Dalian, Liaoning, 116044, China
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Yu Z, Wang J, Lin J, Zhao M, Qiu J. Exploring regulation genes involved in the expression of L-amino acid oxidase in Pseudoalteromonas sp. Rf-1. PLoS One 2015; 10:e0122741. [PMID: 25815733 PMCID: PMC4376890 DOI: 10.1371/journal.pone.0122741] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 02/12/2015] [Indexed: 11/18/2022] Open
Abstract
Bacterial L-amino acid oxidase (LAAO) is believed to play important biological and ecological roles in marine niches, thus attracting increasing attention to understand the regulation mechanisms underlying its production. In this study, we investigated genes involved in LAAO production in marine bacterium Pseudoalteromonas sp. Rf-1 using transposon mutagenesis. Of more than 4,000 mutants screened, 15 mutants showed significant changes in LAAO activity. Desired transposon insertion was confirmed in 12 mutants, in which disrupted genes and corresponding functionswere identified. Analysis of LAAO activity and lao gene expression revealed that GntR family transcriptional regulator, methylase, non-ribosomal peptide synthetase, TonB-dependent heme-receptor family, Na+/H+ antiporter and related arsenite permease, N-acetyltransferase GCN5, Ketol-acid reductoisomerase and SAM-dependent methytransferase, and their coding genes may be involved in either upregulation or downregulation pathway at transcriptional, posttranscriptional, translational and/or posttranslational level. The nhaD and sdmT genes were separately complemented into the corresponding mutants with abolished LAAO-activity. The complementation of either gene can restore LAAO activity and lao gene expression, demonstrating their regulatory role in LAAO biosynthesis. This study provides, for the first time, insights into the molecular mechanisms regulating LAAO production in Pseudoalteromonas sp. Rf-1, which is important to better understand biological and ecological roles of LAAO.
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Affiliation(s)
- Zhiliang Yu
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
- * E-mail: (ZY); (JQ)
| | - Ju Wang
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jianxun Lin
- Department of Electrical Engineering, Columbia University, New York 10027, United States of America
| | - Minyan Zhao
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Juanping Qiu
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
- * E-mail: (ZY); (JQ)
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