1
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Rangaswamy AMM, Roy FM, Keillor JW. Small molecule substrates for the rapid quantification of acyl transfer activity of nylon hydrolase NylC A. Anal Biochem 2024; 693:115598. [PMID: 38964700 DOI: 10.1016/j.ab.2024.115598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 06/06/2024] [Accepted: 06/28/2024] [Indexed: 07/06/2024]
Abstract
The widespread use of polyamides such as nylons has led to the accumulation of nylon waste, which is particularly resistant to decomposition due to the intrinsic stability of the amide bond. New methods are required for the true recycling of these waste materials by depolymerization. Enzymes that are capable of hydrolyzing polyamides have been proposed as biocatalysts that may be suitable for this application. NylC is an enzyme that can mediate the hydrolysis of aminohexanoic acid oligomers, and to some extent, bulk polymers. However, current assays to characterize the activity of this enzyme require long reaction times and/or rely on secondary reactions to quantify hydrolysis. Herein, we have designed structurally-optimized small molecule chromogenic esters that serve as substrate analogues for monitoring NylC acyltransferase activity in a continuous manner. This assay can be performed in minutes at room temperature, and the substrate N-acetyl-GABA-pNP ester (kcat = 0.37 s-1, KM = 256 μM) shows selectivity for NylC in complex biological media. We also demonstrate that activity towards this substrate analogue correlates with amide hydrolysis, which is the primary activity of this enzyme. Furthermore, our screening of substrate analogues provides insight into the substrate specificity of NylC, which is relevant to biocatalytic applications.
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Affiliation(s)
- Alana M M Rangaswamy
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Francis M Roy
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Jeffrey W Keillor
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
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2
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Cengiz M, Sezer CV, Gür B, Bayrakdar A, İzgördü H, Alanyalı F, Öziç C, Kutlu HM. The role of ceranib-2 and its nanoform on the decrease of telomerase levels in human non-small cell cancer. Mol Biol Rep 2024; 51:889. [PMID: 39105852 DOI: 10.1007/s11033-024-09838-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Accepted: 07/31/2024] [Indexed: 08/07/2024]
Abstract
BACKGROUND Ceranib-2, an acid ceramidase (AC) inhibitor, can inhibit cancer cell proliferation and tumor development. However, poor water solubility and low cellular bioavailability limit its efficacy in cancer treatment. METHODS AND RESULTS This study aimed to investigate the cell death induced by ceranib-2 and its solid lipid nanoformulation (ceranib-2-SLN) produced by the hot homogenization technique and the synergistic relationship between ceramide and telomerase in vitro and in silico. Furthermore, this study proved the possible mechanism of ceranib-2-induced AC inhibition by in silico studies. The effective cytotoxic concentrations of ceranib-2, telomerase level, and changes in ceramide levels were measured by MTT colorimetric cytotoxicity assay, ELISA, and LC/MS/MS methods, respectively. TEM results showed that ceranib-2-SLN was 13-fold smaller than the size of ceranib-2. Ceranib-2 and ceranib-2-SLN had IC50 concentrations of 31.62 (± 2.1) and 27.69 (± 1.75) µM in A549, and 48.79 (± 1.56) and 67.98 (± 2.33) in Beas-2B cells. These compounds simultaneously increased ceramide levels and decreased telomerase levels in A549 cells. Ceranib-2 increased telomerase levels while decreasing ceramide levels in Beas-2B cells. It was shown how the synergistic impact of ceranib-2-induced ceramide production and ceramide-induced telomerase level reduction on cytotoxicity in A549 cells. CONCLUSIONS Ceranib-2-SLN was discovered to be more cytotoxic on cancer cells than ceranib-2, suggesting that it could be a promising option for the development of a new anti-cancer agent.
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Affiliation(s)
- Mustafa Cengiz
- Department of Elementary Education, Faculty of Education, Siirt University, Siirt, 56100, Türkiye.
| | - Canan Vejselova Sezer
- Department of Biology, Faculty of Science, Eskişehir Technical University, Eskişehir, 26470, Türkiye
| | - Bahri Gür
- Department of Biochemistry, Faculty of Sciences and Arts, Iğdır University, Iğdır, 76300, Türkiye.
| | - Alpaslan Bayrakdar
- Vocational School of Higher Education for Healthcare Services, Iğdır University, Iğdır, 76000, Türkiye
| | - Hüseyin İzgördü
- Department of Biology, Faculty of Science, Eskişehir Technical University, Eskişehir, 26470, Türkiye
| | - Filiz Alanyalı
- Department of Biology, Faculty of Science, Eskişehir Technical University, Eskişehir, 26470, Türkiye
| | - Cem Öziç
- Department of Medical Biology, Kafkas University, Medicine Faculty, Ahmet Arslan Street, Kars, 36100, Türkiye
| | - Hatice Mehtap Kutlu
- Department of Biology, Faculty of Science, Eskişehir Technical University, Eskişehir, 26470, Türkiye
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3
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Quiroga I, Hernández-González JA, Bautista-Rodríguez E, Benítez-Rojas AC. Exploring the Structurally Conserved Regions and Functional Significance in Bacterial N-Terminal Nucleophile (Ntn) Amide-Hydrolases. Int J Mol Sci 2024; 25:6850. [PMID: 38999960 PMCID: PMC11241749 DOI: 10.3390/ijms25136850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Revised: 06/06/2024] [Accepted: 06/06/2024] [Indexed: 07/14/2024] Open
Abstract
The initial adoption of penicillin as an antibiotic marked the start of exploring other compounds essential for pharmaceuticals, yet resistance to penicillins and their side effects has compromised their efficacy. The N-terminal nucleophile (Ntn) amide-hydrolases S45 family plays a key role in catalyzing amide bond hydrolysis in various compounds, including antibiotics like penicillin and cephalosporin. This study comprehensively analyzes the structural and functional traits of the bacterial N-terminal nucleophile (Ntn) amide-hydrolases S45 family, covering penicillin G acylases, cephalosporin acylases, and D-succinylase. Utilizing structural bioinformatics tools and sequence analysis, the investigation delineates structurally conserved regions (SCRs) and substrate binding site variations among these enzymes. Notably, sixteen SCRs crucial for substrate interaction are identified solely through sequence analysis, emphasizing the significance of sequence data in characterizing functionally relevant regions. These findings introduce a novel approach for identifying targets to enhance the biocatalytic properties of N-terminal nucleophile (Ntn) amide-hydrolases, while facilitating the development of more accurate three-dimensional models, particularly for enzymes lacking structural data. Overall, this research advances our understanding of structure-function relationships in bacterial N-terminal nucleophile (Ntn) amide-hydrolases, providing insights into strategies for optimizing their enzymatic capabilities.
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Affiliation(s)
- Israel Quiroga
- Department of Life and Health Sciences, Universidad Popular Autónoma del Estado de Puebla, 13 Poniente No. 1927, Barrio de Santiago, Puebla 72410, Mexico
| | - Juan Andrés Hernández-González
- Department of Life and Health Sciences, Universidad Popular Autónoma del Estado de Puebla, 13 Poniente No. 1927, Barrio de Santiago, Puebla 72410, Mexico
| | - Elizabeth Bautista-Rodríguez
- Department of Life and Health Sciences, Universidad Popular Autónoma del Estado de Puebla, 13 Poniente No. 1927, Barrio de Santiago, Puebla 72410, Mexico
- Department of Health Sciences, Universidad Autónoma de Tlaxcala, Sur 11, Barrio de Guardia, Zacatelco 90070, Mexico
| | - Alfredo C Benítez-Rojas
- Department of Life and Health Sciences, Universidad Popular Autónoma del Estado de Puebla, 13 Poniente No. 1927, Barrio de Santiago, Puebla 72410, Mexico
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4
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Alenezi T, Alrubaye B, Fu Y, Shrestha J, Algehani S, Wang H, Liyanage R, Sun X. Recombinant Bile Salt Hydrolase Enhances the Inhibition Efficiency of Taurodeoxycholic Acid against Clostridium perfringens Virulence. Pathogens 2024; 13:464. [PMID: 38921762 PMCID: PMC11206707 DOI: 10.3390/pathogens13060464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 05/24/2024] [Accepted: 05/29/2024] [Indexed: 06/27/2024] Open
Abstract
Clostridium perfringens is the main pathogen of chicken necrotic enteritis (NE) causing huge economic losses in the poultry industry. Although dietary secondary bile acid deoxycholic acid (DCA) reduced chicken NE, the accumulation of conjugated tauro-DCA (TDCA) raised concerns regarding DCA efficacy. In this study, we aimed to deconjugate TDCA by bile salt hydrolase (BSH) to increase DCA efficacy against the NE pathogen C. perfringens. Assays were conducted to evaluate the inhibition of C. perfringens growth, hydrogen sulfide (H2S) production, and virulence gene expression by TDCA and DCA. BSH activity and sequence alignment were conducted to select the bsh gene for cloning. The bsh gene from Bifidobacterium longum was PCR-amplified and cloned into plasmids pET-28a (pET-BSH) and pDR111 (pDR-BSH) for expressing the BSH protein in E. coli BL21 and Bacillus subtilis 168 (B-sub-BSH), respectively. His-tag-purified BSH from BL21 cells was evaluated by SDS-PAGE, Coomassie blue staining, and a Western blot (WB) assays. Secretory BSH from B. subtilis was analyzed by a Dot-Blot. B-sub-BSH was evaluated for the inhibition of C. perfringens growth. C. perfringens growth reached 7.8 log10 CFU/mL after 24 h culture. C. perfringens growth was at 8 vs. 7.4, 7.8 vs. 2.6 and 6 vs. 0 log10 CFU/mL in 0.2, 0.5, and 1 mM TDCA vs. DCA, respectively. Compared to TDCA, DCA reduced C. perfringens H2S production and the virulence gene expression of asrA1, netB, colA, and virT. BSH activity was observed in Lactobacillus johnsonii and B. longum under anaerobe but not L. johnsonii under 10% CO2 air. After the sequence alignment of bsh from ten bacteria, bsh from B. longum was selected, cloned into pET-BSH, and sequenced at 951 bp. After pET-BSH was transformed in BL21, BSH expression was assessed around 35 kDa using Coomassie staining and verified for His-tag using WB. After the subcloned bsh and amylase signal peptide sequence was inserted into pDR-BSH, B. subtilis was transformed and named B-sub-BSH. The transformation was evaluated using PCR with B. subtilis around 3 kb and B-sub-BSH around 5 kb. Secretory BSH expressed from B-sub-BSH was determined for His-tag using Dot-Blot. Importantly, C. perfringens growth was reduced greater than 59% log10 CFU/mL in the B-sub-BSH media precultured with 1 vs. 0 mM TDCA. In conclusion, TDCA was less potent than DCA against C. perfringens virulence, and recombinant secretory BSH from B-sub-BSH reduced C. perfringens growth, suggesting a new potential intervention against the pathogen-induced chicken NE.
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Affiliation(s)
- Tahrir Alenezi
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (B.A.); (J.S.); (S.A.); (H.W.)
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA
- College of Medical Applied Sciences, The Northern Border University, Arar 91431, Saudi Arabia
| | - Bilal Alrubaye
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (B.A.); (J.S.); (S.A.); (H.W.)
| | - Ying Fu
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (B.A.); (J.S.); (S.A.); (H.W.)
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA
| | - Janashrit Shrestha
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (B.A.); (J.S.); (S.A.); (H.W.)
| | - Samar Algehani
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (B.A.); (J.S.); (S.A.); (H.W.)
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA
| | - Hong Wang
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (B.A.); (J.S.); (S.A.); (H.W.)
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA
| | - Rohana Liyanage
- Department of Chemistry, University of Arkansas, Fayetteville, AR 72701, USA;
| | - Xiaolun Sun
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (B.A.); (J.S.); (S.A.); (H.W.)
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA
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5
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Jiang X, Shu H, Feng S, Wang P, Zhang Z, Wang N. A Hadal Streptomyces-Derived Echinocandin Acylase Discovered through the Prioritization of Protein Families. Mar Drugs 2024; 22:212. [PMID: 38786603 PMCID: PMC11122479 DOI: 10.3390/md22050212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 04/28/2024] [Accepted: 05/04/2024] [Indexed: 05/25/2024] Open
Abstract
Naturally occurring echinocandin B and FR901379 are potent antifungal lipopeptides featuring a cyclic hexapeptide nucleus and a fatty acid side chain. They are the parent compounds of echinocandin drugs for the treatment of severe fungal infections caused by the Candida and Aspergilla species. To minimize hemolytic toxicity, the native fatty acid side chains in these drug molecules are replaced with designer acyl side chains. The deacylation of the N-acyl side chain is, therefore, a crucial step for the development and manufacturing of echinocandin-type antibiotics. Echinocandin E (ECE) is a novel echinocandin congener with enhanced stability generated via the engineering of the biosynthetic machinery of echinocandin B (ECB). In the present study, we report the discovery of the first echinocandin E acylase (ECEA) using the enzyme similarity tool (EST) for enzymatic function mining across protein families. ECEA is derived from Streptomyces sp. SY1965 isolated from a sediment collected from the Mariana Trench. It was cloned and heterologously expressed in S. lividans TK24. The resultant TKecea66 strain showed efficient cleavage activity of the acyl side chain of ECE, showing promising applications in the development of novel echinocandin-type therapeutics. Our results also provide a showcase for harnessing the essentially untapped biodiversity from the hadal ecosystems for the discovery of functional molecules.
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Affiliation(s)
- Xuejian Jiang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
| | - Hongjun Shu
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
| | - Shuting Feng
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
| | - Pinmei Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
- Hainan Institute of Zhejiang University, Sanya 572025, China
| | - Zhizhen Zhang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
| | - Nan Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
- Hainan Institute of Zhejiang University, Sanya 572025, China
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6
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John T, Saffoon N, Walsby-Tickle J, Hester SS, Dingler FA, Millington CL, McCullagh JSO, Patel KJ, Hopkinson RJ, Schofield CJ. Aldehyde-mediated inhibition of asparagine biosynthesis has implications for diabetes and alcoholism. Chem Sci 2024; 15:2509-2517. [PMID: 38362406 PMCID: PMC10866355 DOI: 10.1039/d3sc06551k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 01/01/2024] [Indexed: 02/17/2024] Open
Abstract
Patients with alcoholism and type 2 diabetes manifest altered metabolism, including elevated aldehyde levels and unusually low asparagine levels. We show that asparagine synthetase B (ASNS), the only human asparagine-forming enzyme, is inhibited by disease-relevant reactive aldehydes, including formaldehyde and acetaldehyde. Cellular studies show non-cytotoxic amounts of reactive aldehydes induce a decrease in asparagine levels. Biochemical analyses reveal inhibition results from reaction of the aldehydes with the catalytically important N-terminal cysteine of ASNS. The combined cellular and biochemical results suggest a possible mechanism underlying the low asparagine levels in alcoholism and diabetes. The results will stimulate research on the biological consequences of the reactions of aldehydes with nucleophilic residues.
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Affiliation(s)
- Tobias John
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Nadia Saffoon
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - John Walsby-Tickle
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Svenja S Hester
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford Oxford UK
| | - Felix A Dingler
- MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital/Headley Way Oxford OX3 9DS UK
| | - Christopher L Millington
- MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital/Headley Way Oxford OX3 9DS UK
| | - James S O McCullagh
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Ketan J Patel
- MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital/Headley Way Oxford OX3 9DS UK
| | - Richard J Hopkinson
- Leicester Institute for Structural and Chemical Biology and School of Chemistry, University of Leicester, Henry Wellcome Building Lancaster Road Leicester LE1 7RH UK
| | - Christopher J Schofield
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
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7
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Mitrić A, Castellano I. Targeting gamma-glutamyl transpeptidase: A pleiotropic enzyme involved in glutathione metabolism and in the control of redox homeostasis. Free Radic Biol Med 2023; 208:672-683. [PMID: 37739139 DOI: 10.1016/j.freeradbiomed.2023.09.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 09/07/2023] [Accepted: 09/18/2023] [Indexed: 09/24/2023]
Abstract
Gamma-glutamyl transpeptidase (GGT) is an enzyme located on the outer membrane of the cells where it regulates the metabolism of glutathione (GSH), the most abundant intracellular antioxidant thiol. GGT plays a key role in the control of redox homeostasis, by hydrolyzing extracellular GSH and providing the cell with the recovery of cysteine, which is necessary for de novo intracellular GSH and protein biosynthesis. Therefore, the upregulation of GGT confers to the cell greater resistance to oxidative stress and the advantage of growing fast. Indeed, GGT is upregulated in inflammatory conditions and in the progression of various human tumors and it is involved in many physiological disorders related to oxidative stress, such as cardiovascular disease and diabetes. Currently, increased GGT expression is considered a marker of liver damage, cancer, and low-grade chronic inflammation. This review addresses the current knowledge on the structure-function relationship of GGT, focusing on human GGT, and provides information on the pleiotropic biological role and relevance of the enzyme as a target of drugs aimed at alleviating oxidative stress-related diseases. The development of new GGT inhibitors is critically discussed, as are the advantages and disadvantages of their potential use in clinics. Considering its pleiotropic activities and evolved functions, GGT is a potential "moonlighting protein".
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Affiliation(s)
- Aleksandra Mitrić
- Institute of Clinical and Molecular Virology, Friedrich-Alexander University Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - Immacolata Castellano
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131, Naples, Italy; Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy.
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8
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Andjelkovic M, Zinovjev K, Ramos-Guzmán CA, Ruiz- Pernía JJ, Tuñón I. Elucidation of the Active Form and Reaction Mechanism in Human Asparaginase Type III Using Multiscale Simulations. J Chem Inf Model 2023; 63:5676-5688. [PMID: 37635309 PMCID: PMC10852353 DOI: 10.1021/acs.jcim.3c00900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Indexed: 08/29/2023]
Abstract
l-asparaginases catalyze the asparagine hydrolysis to aspartate. These enzymes play an important role in the treatment of acute lymphoblastic leukemia because these cells are unable to produce their own asparagine. Due to the immunogenic response and various side effects of enzymes of bacterial origin, many attempts have been made to replace these enzymes with mammalian enzymes such as human asparaginase type III (hASNaseIII). This study investigates the reaction mechanism of hASNaseIII through molecular dynamics simulations, quantum mechanics/molecular mechanics methods, and free energy calculations. Our simulations reveal that the dimeric form of the enzyme plays a vital role in stabilizing the substrate in the active site, despite the active site residues coming from a single protomer. Protomer-protomer interactions are essential to keep the enzyme in an active conformation. Our study of the reaction mechanism indicates that the self-cleavage process that generates an N-terminal residue (Thr168) is required to activate the enzyme. This residue acts as the nucleophile, attacking the electrophilic carbon of the substrate after a proton transfer from its hydroxyl group to the N-terminal amino group. The reaction mechanism proceeds with the formation of an acyl-enzyme complex and its hydrolysis, which turns out to be the rate-determining step. Our proposal of the enzymatic mechanism sheds light on the role of different active site residues and rationalizes the studies on mutations. The insights provided here about hASNaseIII activity could contribute to the comprehension of the disparities among different ASNases and might even guide the design of new variants with improved properties for acute lymphoblastic leukemia treatment.
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Affiliation(s)
- Milorad Andjelkovic
- Departamento
de Química Física, Universidad
de Valencia, 46100 Burjassot, Spain
| | - Kirill Zinovjev
- Departamento
de Química Física, Universidad
de Valencia, 46100 Burjassot, Spain
| | - Carlos Alberto Ramos-Guzmán
- Departamento
de Química Física, Universidad
de Valencia, 46100 Burjassot, Spain
- Instituto
de Materiales Avanzados, Universidad Jaume
I, 12071 Castelló, Spain
| | | | - Iñaki Tuñón
- Departamento
de Química Física, Universidad
de Valencia, 46100 Burjassot, Spain
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9
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Guedes RA, Grilo JH, Carvalho AN, Fernandes PMP, Ressurreição AS, Brito V, Santos AO, Silvestre S, Gallerani E, Gama MJ, Gavioli R, Salvador JAR, Guedes RC. New Scaffolds of Proteasome Inhibitors: Boosting Anticancer Potential by Exploiting the Synergy of In Silico and In Vitro Methodologies. Pharmaceuticals (Basel) 2023; 16:1096. [PMID: 37631011 PMCID: PMC10458307 DOI: 10.3390/ph16081096] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 07/26/2023] [Accepted: 07/31/2023] [Indexed: 08/27/2023] Open
Abstract
Cancer is a complex multifactorial disease whose pathophysiology involves multiple metabolic pathways, including the ubiquitin-proteasome system, for which several proteasome inhibitors have already been approved for clinical use. However, the resistance to existing therapies and the occurrence of severe adverse effects is still a concern. The purpose of this study was the discovery of novel scaffolds of proteasome inhibitors with anticancer activity, aiming to overcome the limitations of the existing proteasome inhibitors. Thus, a structure-based virtual screening protocol was developed using the structure of the human 20S proteasome, and 246 compounds from virtual databases were selected for in vitro evaluation, namely proteasome inhibition assays and cell viability assays. Compound 4 (JHG58) was shortlisted as the best hit compound based on its potential in terms of proteasome inhibitory activity and its ability to induce cell death (both with IC50 values in the low micromolar range). Molecular docking studies revealed that compound 4 interacts with key residues, namely with the catalytic Thr1, Ala20, Thr21, Lys33, and Asp125 at the chymotrypsin-like catalytic active site. The hit compound is a good candidate for additional optimization through a hit-to-lead campaign.
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Affiliation(s)
- Romina A. Guedes
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisboa, Portugal or (R.A.G.); (J.H.G.); (A.N.C.); (P.M.P.F.); (A.S.R.); (M.J.G.)
- Center for Innovative Biomedicine and Biotechnology (CIBB), Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Laboratory of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Jorge H. Grilo
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisboa, Portugal or (R.A.G.); (J.H.G.); (A.N.C.); (P.M.P.F.); (A.S.R.); (M.J.G.)
| | - Andreia N. Carvalho
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisboa, Portugal or (R.A.G.); (J.H.G.); (A.N.C.); (P.M.P.F.); (A.S.R.); (M.J.G.)
| | - Pedro M. P. Fernandes
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisboa, Portugal or (R.A.G.); (J.H.G.); (A.N.C.); (P.M.P.F.); (A.S.R.); (M.J.G.)
- Center for Innovative Biomedicine and Biotechnology (CIBB), Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Laboratory of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Ana S. Ressurreição
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisboa, Portugal or (R.A.G.); (J.H.G.); (A.N.C.); (P.M.P.F.); (A.S.R.); (M.J.G.)
| | - Vanessa Brito
- Health Sciences Research Centre (CICS-UBI), University of Beira Interior, 6200-506 Covilhã, Portugal; (V.B.); (A.O.S.); (S.S.)
| | - Adriana O. Santos
- Health Sciences Research Centre (CICS-UBI), University of Beira Interior, 6200-506 Covilhã, Portugal; (V.B.); (A.O.S.); (S.S.)
| | - Samuel Silvestre
- Health Sciences Research Centre (CICS-UBI), University of Beira Interior, 6200-506 Covilhã, Portugal; (V.B.); (A.O.S.); (S.S.)
| | - Eleonora Gallerani
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, 44121 Ferrara, Italy;
| | - Maria João Gama
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisboa, Portugal or (R.A.G.); (J.H.G.); (A.N.C.); (P.M.P.F.); (A.S.R.); (M.J.G.)
| | - Riccardo Gavioli
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, 44121 Ferrara, Italy;
| | - Jorge A. R. Salvador
- Center for Innovative Biomedicine and Biotechnology (CIBB), Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Laboratory of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Rita C. Guedes
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisboa, Portugal or (R.A.G.); (J.H.G.); (A.N.C.); (P.M.P.F.); (A.S.R.); (M.J.G.)
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10
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Makris C, Leckrone JK, Butler A. Tistrellabactins A and B Are Photoreactive C-Diazeniumdiolate Siderophores from the Marine-Derived Strain Tistrella mobilis KA081020-065. JOURNAL OF NATURAL PRODUCTS 2023; 86:1770-1778. [PMID: 37341506 PMCID: PMC10391617 DOI: 10.1021/acs.jnatprod.3c00230] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Indexed: 06/22/2023]
Abstract
The C-diazeniumdiolate group in the amino acid graminine is emerging as a new microbially produced Fe(III) coordinating ligand in siderophores, which is photoreactive. While the few siderophores reported from this class have only been isolated from soil-associated microbes, here we report the first C-diazeniumdiolate siderophores tistrellabactins A and B, isolated from the bioactive marine-derived strain Tistrella mobilis KA081020-065. The structural characterization of the tistrellabactins reveals unique biosynthetic features including an NRPS module iteratively loading glutamine residues and a promiscuous adenylation domain yielding either tistrellabactin A with an asparagine residue or tistrellabactin B with an aspartic acid residue at analogous positions. Beyond the function of scavenging Fe(III) for growth, these siderophores are photoreactive upon irradiation with UV light, releasing the equivalent of nitric oxide (NO) and an H atom from the C-diazeniumdiolate group. Fe(III)-tistrellabactin is also photoreactive, with both the C-diazeniumdiolate and the β-hydroxyaspartate residues undergoing photoreactions, resulting in a photoproduct without the ability to chelate Fe(III).
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Affiliation(s)
- Christina Makris
- Department of Chemistry &
Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - Jamie K. Leckrone
- Department of Chemistry &
Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - Alison Butler
- Department of Chemistry &
Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
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11
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Negoro S, Shibata N, Kato DI, Tanaka Y, Yasuhira K, Nagai K, Oshima S, Furuno Y, Yokoyama R, Miyazaki K, Takeo M, Hengphasatporn K, Shigeta Y, Lee YH, Higuchi Y. X-ray crystallographic and mutational analysis of the NylC precursor: catalytic mechanism of autocleavage and substrate hydrolysis of nylon hydrolase. FEBS J 2023. [PMID: 36799721 DOI: 10.1111/febs.16755] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 02/04/2023] [Accepted: 02/16/2023] [Indexed: 02/18/2023]
Abstract
Nylon hydrolase (NylC), a member of the N-terminal nucleophile (Ntn) hydrolase superfamily, is responsible for the degradation of various aliphatic nylons, including nylon-6 and nylon-66. NylC is initially expressed as an inactive precursor (36 kDa), but the precursor is autocatalytically cleaved at Asn266/Thr267 to generate an active enzyme composed of 27 and 9 kDa subunits. We isolated various mutants with amino acid changes at the catalytic centre. X-ray crystallographic analysis revealed that the NylC precursor forms a doughnut-shaped quaternary structure composed of four monomers (molecules A-D) with D2 symmetry. Catalytic residues in the precursor are covered by loop regions at the A/B interface (equivalent to the C/D interface). However, the catalytic residues are exposed to the solvent environment through autocleavage followed by movements of the loop regions. T267A, D306A and D308A mutations resulted in a complete loss of autocleavage. By contrast, in the T267S mutant, autocleavage proceeded slowly at a constant reaction rate (k = 2.8 × 10-5 s-1 ) until complete conversion, but the reaction was inhibited by K189A and N219A mutations. Based on the crystallographic and molecular dynamic simulation analyses, we concluded that the Asp308-Asp306-Thr267 triad, resembling the Glu-Ser-Ser triad conserved in Ntn-hydrolase family enzymes, is responsible for autocleavage and that hydrogen-bonding networks connecting Thr267 with Lys189 and Asn219 are required for increasing the nucleophilicity of Thr267-OH in both the water accessible and water inaccessible systems. Furthermore, we determined that NylC employs the Asp308-Asp306-Thr267 triad as catalytic residues for substrate hydrolysis, but the reaction requires Lys189 and Tyr146 as additional catalytic/substrate-binding residues specific for nylon hydrolysis.
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Affiliation(s)
- Seiji Negoro
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, Himeji, Japan
| | - Naoki Shibata
- Department of Life Science, Graduate School of Science, University of Hyogo, Ako-gun, Japan
| | - Dai-Ichiro Kato
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, Japan
| | - Yusuke Tanaka
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, Himeji, Japan
| | - Kengo Yasuhira
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, Himeji, Japan
| | - Keisuke Nagai
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, Himeji, Japan
| | - Shohei Oshima
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, Himeji, Japan
| | - Yoko Furuno
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, Japan
| | - Risa Yokoyama
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, Japan
| | - Kaito Miyazaki
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, Japan
| | - Masahiro Takeo
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, Himeji, Japan
| | | | - Yasuteru Shigeta
- Center for Computational Sciences, University of Tsukuba, Tsukuba, Japan
| | - Young-Ho Lee
- Institute for Protein Research, Osaka University, Suita, Japan.,Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Cheongju-si, South Korea.,Bio-Analytical Science, University of Science and Technology, Daejeon, South Korea.,Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, South Korea
| | - Yoshiki Higuchi
- Department of Life Science, Graduate School of Science, University of Hyogo, Ako-gun, Japan
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12
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Öztürk M, Kılıçsaymaz Z, Önal C. Site-Directed Mutagenesis of Bile Salt Hydrolase (BSH) from Lactobacillus plantarum B14 Confirms the Importance of the V58 and Y65 Amino Acids for Activity and Substrate Specificity. FOOD BIOTECHNOL 2023. [DOI: 10.1080/08905436.2022.2164299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Mehmet Öztürk
- Department of Biology, Faculty of Arts and Science, Bolu Abant Izzet Baysal University, Bolu, Turkey
| | - Zekiye Kılıçsaymaz
- Department of Biology, Faculty of Arts and Science, Bolu Abant Izzet Baysal University, Bolu, Turkey
| | - Cansu Önal
- Department of Biology, Faculty of Arts and Science, Bolu Abant Izzet Baysal University, Bolu, Turkey
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13
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Aguirre AM, Adegbite AO, Sorg JA. Clostridioides difficile bile salt hydrolase activity has substrate specificity and affects biofilm formation. NPJ Biofilms Microbiomes 2022; 8:94. [PMID: 36450806 PMCID: PMC9712596 DOI: 10.1038/s41522-022-00358-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/14/2022] [Indexed: 12/02/2022] Open
Abstract
The Clostridioides difficile pathogen is responsible for nosocomial infections. Germination is an essential step for the establishment of C. difficile infection (CDI) because toxins that are secreted by vegetative cells are responsible for the symptoms of CDI. Germination can be stimulated by the combinatorial actions of certain amino acids and either conjugated or deconjugated cholic acid-derived bile salts. During synthesis in the liver, cholic acid- and chenodeoxycholic acid-class bile salts are conjugated with either taurine or glycine at the C24 carboxyl. During GI transit, these conjugated bile salts are deconjugated by microbes that express bile salt hydrolases (BSHs). Here, we surprisingly find that several C. difficile strains have BSH activity. We observed this activity in both C. difficile vegetative cells and in spores and that the observed BSH activity was specific to taurine-derived bile salts. Additionally, we find that this BSH activity can produce cholate for metabolic conversion to deoxycholate by C. scindens. The C. scindens-produced deoxycholate signals to C. difficile to initiate biofilm formation. Our results show that C. difficile BSH activity has the potential to influence the interactions between microbes, and this could extend to the GI setting.
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Affiliation(s)
| | | | - Joseph A Sorg
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA.
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14
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Yang CI, Zhu Z, Jones JJ, Lomenick B, Chou TF, Shan SO. System-wide analyses reveal essential roles of N-terminal protein modification in bacterial membrane integrity. iScience 2022; 25:104756. [PMID: 35942092 PMCID: PMC9356101 DOI: 10.1016/j.isci.2022.104756] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 06/20/2022] [Accepted: 07/07/2022] [Indexed: 11/18/2022] Open
Abstract
The removal of the N-terminal formyl group on nascent proteins by peptide deformylase (PDF) is the most prevalent protein modification in bacteria. PDF is a critical target of antibiotic development; however, its role in bacterial physiology remains a long-standing question. This work used the time-resolved analyses of the Escherichia coli translatome and proteome to investigate the consequences of PDF inhibition. Loss of PDF activity rapidly induces cellular stress responses, especially those associated with protein misfolding and membrane defects, followed by a global down-regulation of metabolic pathways. Rapid membrane hyperpolarization and impaired membrane integrity were observed shortly after PDF inhibition, suggesting that the plasma membrane disruption is the most immediate and primary consequence of formyl group retention on nascent proteins. This work resolves the physiological function of a ubiquitous protein modification and uncovers its crucial role in maintaining the structure and function of the bacterial membrane.
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Affiliation(s)
- Chien-I Yang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Zikun Zhu
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Jeffrey J. Jones
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, CA, USA
| | - Brett Lomenick
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, CA, USA
| | - Tsui-Fen Chou
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, CA, USA
| | - Shu-ou Shan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
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15
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Kusada H, Arita M, Tohno M, Tamaki H. Bile Salt Hydrolase Degrades β-Lactam Antibiotics and Confers Antibiotic Resistance on Lactobacillus paragasseri. Front Microbiol 2022; 13:858263. [PMID: 35733973 PMCID: PMC9207391 DOI: 10.3389/fmicb.2022.858263] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 05/05/2022] [Indexed: 12/12/2022] Open
Abstract
Bile salt hydrolase (BSH) is a well-characterized probiotic enzyme associated with bile detoxification and colonization of lactic acid bacteria in the human gastrointestinal tract. Here, we isolated a putative BSH (LpBSH) from the probiotic bacterium Lactobacillus paragasseri JCM 5343T and demonstrated its bifunctional activity that allows it to degrade not only bile salts but also the antibiotic (penicillin). Although antibiotic resistance and bile detoxification have been separately recognized as different microbial functions, our findings suggest that bifunctional BSHs simultaneously confer ecological advantages to host gut bacteria to improve their survival in the mammalian intestine by attaining a high resistance to bile salts and β-lactams. Strain JCM 5343T showed resistance to both bile salts and β-lactam antibiotics, suggesting that LpBSH may be involved in this multi-resistance of the strain. We further verified that such bifunctional enzymes were broadly distributed among the phylogeny, suggesting that the bifunctionality may be conserved in other BSHs of gut bacteria. This study revealed the physiological role and phylogenetic diversity of bifunctional enzymes degrading bile salts and β-lactams in gut bacteria. Furthermore, our findings suggest that the hitherto-overlooked penicillin-degrading activity of penicillin acylase could be a potential new target for the probiotic function of gut bacteria.
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Affiliation(s)
- Hiroyuki Kusada
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
| | - Masanori Arita
- Bioinformation and DDBJ Center, National Institute of Genetics, Mishima, Japan
| | - Masanori Tohno
- Research Center of Genetic Resources, Core Technology Research Headquarters, National Agriculture and Food Research Organization, Tsukuba, Japan
- Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization, Nasushiobara, Japan
| | - Hideyuki Tamaki
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
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16
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Linhorst A, Lübke T. The Human Ntn-Hydrolase Superfamily: Structure, Functions and Perspectives. Cells 2022; 11:cells11101592. [PMID: 35626629 PMCID: PMC9140057 DOI: 10.3390/cells11101592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 01/27/2023] Open
Abstract
N-terminal nucleophile (Ntn)-hydrolases catalyze the cleavage of amide bonds in a variety of macromolecules, including the peptide bond in proteins, the amide bond in N-linked protein glycosylation, and the amide bond linking a fatty acid to sphingosine in complex sphingolipids. Ntn-hydrolases are all sharing two common hallmarks: Firstly, the enzymes are synthesized as inactive precursors that undergo auto-proteolytic self-activation, which, as a consequence, reveals the active site nucleophile at the newly formed N-terminus. Secondly, all Ntn-hydrolases share a structural consistent αββα-fold, notwithstanding the total lack of amino acid sequence homology. In humans, five subclasses of the Ntn-superfamily have been identified so far, comprising relevant members such as the catalytic active subunits of the proteasome or a number of lysosomal hydrolases, which are often associated with lysosomal storage diseases. This review gives an updated overview on the structural, functional, and (patho-)physiological characteristics of human Ntn-hydrolases, in particular.
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17
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Biosynthetic process and strain improvement approaches for industrial penicillin production. Biotechnol Lett 2022; 44:179-192. [PMID: 35000028 DOI: 10.1007/s10529-022-03222-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 01/01/2022] [Indexed: 11/02/2022]
Abstract
Penicillins and cephalosporins are the most important class of beta (β) lactam antibiotics, accounting for 65% total antibiotic market. Penicillins are produced by Penicillium rubens (popularly known as P. chrysogenum) were used to synthesize the active pharmaceutical intermediate (API), 6-aminopenicillinic acid (6-APA) employed in semisynthetic antibiotic production. The wild strains produce a negligible amount of penicillin (Pen). High antibiotic titre-producing P. chrysogenum strains are necessitating for industrial Pen production to meet global demand at lower prices. Classical strain improvement (CSI) approaches such as random mutagenesis, medium engineering, and fermentation are the cornerstones for high-titer Pen production. Since, Sir Alexander Fleming Discovery of Pen, great efforts are expanded to develop at a commercial scale antibiotics producing strains. Breakthroughs in genetic engineering, heterologous expression and CRISPR/Cas9 genome editing tools opened a new window for Pen production at a commercial scale to assure health crisis. The current state of knowledge, limitations of CSI and genetic engineering approaches to Pen production are discussed in this review.
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18
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Closantel is an allosteric inhibitor of human Taspase1. iScience 2021; 24:103524. [PMID: 34934933 DOI: 10.1016/j.isci.2021.103524] [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: 08/02/2021] [Revised: 11/11/2021] [Accepted: 11/23/2021] [Indexed: 11/23/2022] Open
Abstract
Dimerization of Taspase1 activates an intrinsic serine protease function that leads to the catalytic Thr234 residue, which allows to catalyze the consensus sequence Q-3X-2D-1⋅G1X2D3D4, present in Trithorax family members and TFIIA. Noteworthy, Taspase1 performs only a single hydrolytic step on substrate proteins, which makes it impossible to screen for inhibitors in a classical screening approach. Here, we report the development of an HTRF reporter assay that allowed the identification of an inhibitor, Closantel sodium, that inhibits Taspase1 in a noncovalent fashion (IC50 = 1.6 μM). The novel inhibitor interferes with the dimerization step and/or the intrinsic serine protease function of the proenzyme. Of interest, Taspase1 is required to activate the oncogenic functions of the leukemogenic AF4-MLL fusion protein and was shown in several studies to be overexpressed in many solid tumors. Therefore, the inhibitor may be useful for further validation of Taspase1 as a target for cancer therapy.
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19
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de Celis M, Serrano-Aguirre L, Belda I, Liébana-García R, Arroyo M, Marquina D, de la Mata I, Santos A. Acylase enzymes disrupting quorum sensing alter the transcriptome and phenotype of Pseudomonas aeruginosa, and the composition of bacterial biofilms from wastewater treatment plants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 799:149401. [PMID: 34364277 DOI: 10.1016/j.scitotenv.2021.149401] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 07/28/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
Biofilms represent an essential way of life and colonization of new environments for microorganisms. This feature is regulated by quorum sensing (QS), a microbial communication system based on autoinducer molecules, such as N-acyl-homoserine lactones (AHLs) in Gram negative bacteria. In artificial ecosystems, like Wastewater Treatment Plants (WWTPs), biofilm attachment in filtration membranes produces biofouling. In this environment, the microbial communities are mostly composed of Gram-negative phyla. Thus, we used two AHLs-degrading enzymes, obtained from Actinoplanes utahensis (namely AuAAC and AuAHLA) to determine the effects of degradation of QS signals in the biofilm formation, among other virulence factors, of a Pseudomonas aeruginosa strain isolated from a WWTP, assessing molecular mechanisms through transcriptomics. Besides, we studied the possible effects on community composition in biofilms from activated sludge samples. Although the studied enzymes only degraded the AHLs involved in one of the four QS systems of P. aeruginosa, these activities produced the deregulation of the complete QS network. In fact, AuAAC -the enzyme with higher catalytic efficiency- deregulated all the four QS systems. However, both enzymes reduced the biofilm formation and pyocyanin and protease production. The transcriptomic response of P. aeruginosa affected QS related genes, moreover, transcriptomic response to AuAAC affected mainly to QS related genes. Regarding community composition of biofilms, as expected, the abundance of Gram-negative phyla was significantly decreased after enzymatic treatment. These results support the potential use of such AHLs-degrading enzymes as a method to reduce biofilm formation in WWTP membranes and ameliorate bacterial virulence.
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Affiliation(s)
- M de Celis
- Department of Genetics, Physiology and Microbiology, Microbiology Unit, Faculty of Biology, Complutense University of Madrid, José Antonio Novais 12, 28040 Madrid, Spain
| | - L Serrano-Aguirre
- Department of Biochemistry and Molecular Biology, Faculty of Biology, Complutense University of Madrid, José Antonio Novais 12, 28040 Madrid, Spain
| | - I Belda
- Department of Genetics, Physiology and Microbiology, Microbiology Unit, Faculty of Biology, Complutense University of Madrid, José Antonio Novais 12, 28040 Madrid, Spain
| | - R Liébana-García
- Department of Genetics, Physiology and Microbiology, Microbiology Unit, Faculty of Biology, Complutense University of Madrid, José Antonio Novais 12, 28040 Madrid, Spain
| | - M Arroyo
- Department of Biochemistry and Molecular Biology, Faculty of Biology, Complutense University of Madrid, José Antonio Novais 12, 28040 Madrid, Spain
| | - D Marquina
- Department of Genetics, Physiology and Microbiology, Microbiology Unit, Faculty of Biology, Complutense University of Madrid, José Antonio Novais 12, 28040 Madrid, Spain
| | - I de la Mata
- Department of Biochemistry and Molecular Biology, Faculty of Biology, Complutense University of Madrid, José Antonio Novais 12, 28040 Madrid, Spain
| | - A Santos
- Department of Genetics, Physiology and Microbiology, Microbiology Unit, Faculty of Biology, Complutense University of Madrid, José Antonio Novais 12, 28040 Madrid, Spain.
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20
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Ruiz CH, Osorio-Llanes E, Trespalacios MH, Mendoza-Torres E, Rosales W, Gómez CMM. Quorum Sensing Regulation as a Target for Antimicrobial Therapy. Mini Rev Med Chem 2021; 22:848-864. [PMID: 34856897 DOI: 10.2174/1389557521666211202115259] [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: 10/04/2020] [Revised: 05/20/2021] [Accepted: 09/04/2021] [Indexed: 11/22/2022]
Abstract
Some bacterial species use a cell-to-cell communication mechanism called Quorum Sensing (QS). Bacteria release small diffusible molecules, usually termed signals which allow the activation of beneficial phenotypes that guarantee bacterial survival and the expression of a diversity of virulence genes in response to an increase in population density. The study of the molecular mechanisms that relate signal molecules with bacterial pathogenesis is an area of growing interest due to its use as a possible therapeutic alternative through the development of synthetic analogues of autoinducers as a strategy to regulate bacterial communication as well as the study of bacterial resistance phenomena, the study of these relationships is based on the structural diversity of natural or synthetic autoinducers and their ability to inhibit bacterial QS, which can be approached with a molecular perspective from the following topics: i) Molecular signals and their role in QS regulation; ii) Strategies in the modulation of Quorum Sensing; iii) Analysis of Bacterial QS circuit regulation strategies; iv) Structural evolution of natural and synthetic autoinducers as QS regulators. This mini-review allows a molecular view of the QS systems, showing a perspective on the importance of the molecular diversity of autoinducer analogs as a strategy for the design of new antimicrobial agents.
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Affiliation(s)
- Caterine Henríquez Ruiz
- Grupo de Investigación en Química Orgánica y Biomédica. Faculty of Basic Sciences. Universidad del Atlántico. Barranquilla. Colombia
| | - Estefanie Osorio-Llanes
- Faculty of Exact and Natural sciences. Grupo de Investigación Avanzada en Biomedicina. Universidad Libre. Barranquilla. Colombia
| | - Mayra Hernández Trespalacios
- Grupo de Investigación en Química Orgánica y Biomédica. Faculty of Basic Sciences. Universidad del Atlántico. Barranquilla. Colombia
| | - Evelyn Mendoza-Torres
- Faculty of Health Sciences. Grupo de Investigación Avanzada en Biomedicina-Universidad Libre. Barranquilla. Colombia
| | - Wendy Rosales
- Faculty of Exact and Natural sciences. Grupo de Investigación Avanzada en Biomedicina. Universidad Libre. Barranquilla. Colombia
| | - Carlos Mario Meléndez Gómez
- Grupo de Investigación en Química Orgánica y Biomédica. Faculty of Basic Sciences. Universidad del Atlántico. Barranquilla. Colombia
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21
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Koeller CM, Smith TK, Gulick AM, Bangs JD. p67: a cryptic lysosomal hydrolase in Trypanosoma brucei? Parasitology 2021; 148:1271-1276. [PMID: 33070788 PMCID: PMC8053727 DOI: 10.1017/s003118202000195x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/22/2020] [Accepted: 10/08/2020] [Indexed: 12/15/2022]
Abstract
p67 is a type I transmembrane glycoprotein of the terminal lysosome of African trypanosomes. Its biosynthesis involves transport of an initial gp100 ER precursor to the lysosome, followed by cleavage to N-terminal (gp32) and C-terminal (gp42) subunits that remain non-covalently associated. p67 knockdown is lethal, but the only overt phenotype is an enlarged lysosome (~250 to >1000 nm). Orthologues have been characterized in Dictyostelium and mammals. These have processing pathways similar to p67, and are thought to have phospholipase B-like (PLBL) activity. The mouse PLBD2 crystal structure revealed that the PLBLs represent a subgroup of the larger N-terminal nucleophile (NTN) superfamily, all of which are hydrolases. NTNs activate by internal autocleavage mediated by a nucleophilic residue, i.e. Cys, Ser or Thr, on the upstream peptide bond to form N-terminal α (gp32) and C-terminal β (gp42) subunits that remain non-covalently associated. The N-terminal residue of the β subunit is then catalytic in subsequent hydrolysis reactions. All PLBLs have a conserved Cys/Ser dipeptide at the α/β junction (Cys241/Ser242 in p67), mutation of which renders p67 non-functional in RNAi rescue assays. p67 orthologues are found in many clades of parasitic protozoa, thus p67 is the founding member of a group of hydrolases that likely play a role broadly in the pathogenesis of parasitic infections.
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Affiliation(s)
- Carolina M. Koeller
- Department of Microbiology & Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo (SUNY), Buffalo, NY14203, USA
| | - Terry K. Smith
- Schools of Biology & Chemistry, BSRC, University of St. Andrews, St Andrews, FifeKY16 9ST, UK
| | - Andrew M. Gulick
- Department of Structural Biology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo (SUNY), Buffalo, NY14203, USA
| | - James D. Bangs
- Department of Microbiology & Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo (SUNY), Buffalo, NY14203, USA
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22
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Serrano-Aguirre L, Velasco-Bucheli R, García-Álvarez B, Saborido A, Arroyo M, de la Mata I. Novel Bifunctional Acylase from Actinoplanes utahensis: A Versatile Enzyme to Synthesize Antimicrobial Compounds and Use in Quorum Quenching Processes. Antibiotics (Basel) 2021; 10:antibiotics10080922. [PMID: 34438972 PMCID: PMC8388760 DOI: 10.3390/antibiotics10080922] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 07/25/2021] [Accepted: 07/27/2021] [Indexed: 12/02/2022] Open
Abstract
Many intercellular communication processes, known as quorum sensing (QS), are regulated by the autoinducers N-acyl-l-homoserine lactones (AHLs) in Gram-negative bacteria. The inactivation of these QS processes using different quorum quenching (QQ) strategies, such as enzymatic degradation of the autoinducers or the receptor blocking with non-active analogs, could be the basis for the development of new antimicrobials. This study details the heterologous expression, purification, and characterization of a novel N-acylhomoserine lactone acylase from Actinoplanes utahensis NRRL 12052 (AuAHLA), which can hydrolyze different natural penicillins and N-acyl-homoserine lactones (with or without 3-oxo substitution), as well as synthesize them. Kinetic parameters for the hydrolysis of a broad range of substrates have shown that AuAHLA prefers penicillin V, followed by C12-HSL. In addition, AuAHLA inhibits the production of violacein by Chromobacterium violaceum CV026, confirming its potential use as a QQ agent. Noteworthy, AuAHLA is also able to efficiently synthesize penicillin V, besides natural AHLs and phenoxyacetyl-homoserine lactone (POHL), a non-natural analog of AHLs that could be used to block QS receptors and inhibit signal of autoinducers, being the first reported AHL acylase capable of synthesizing AHLs.
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23
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Fuchs ACD, Alva V, Lupas AN. An astonishing wealth of new proteasome homologs. Bioinformatics 2021; 37:4694-4703. [PMID: 34323935 PMCID: PMC8665760 DOI: 10.1093/bioinformatics/btab558] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 07/02/2021] [Accepted: 07/28/2021] [Indexed: 11/21/2022] Open
Abstract
Motivation The proteasome is the main proteolytic machine for targeted protein degradation in archaea and eukaryotes. While some bacteria also possess the proteasome, most of them contain a simpler and more specialized homolog, the heat shock locus V protease. In recent years, three further homologs of the proteasome core subunits have been characterized in prokaryotes: Anbu, BPH and connectase. With the inclusion of these members, the family of proteasome-like proteins now exhibits a range of architectural and functional forms, from the canonical proteasome, a barrel-shaped protease without pronounced intrinsic substrate specificity, to the monomeric connectase, a highly specific protein ligase. Results We employed systematic sequence searches to show that we have only seen the tip of the iceberg so far and that beyond the hitherto known proteasome homologs lies a wealth of distantly related, uncharacterized homologs. We describe a total of 22 novel proteasome homologs in bacteria and archaea. Using sequence and structure analysis, we analyze their evolutionary history and assess structural differences that may modulate their function. With this initial description, we aim to stimulate the experimental investigation of these novel proteasome-like family members. Availability and implementation The protein sequences in this study are searchable in the MPI Bioinformatics Toolkit (https://toolkit.tuebingen.mpg.de) with ProtBLAST/PSI-BLAST and with HHpred (database ‘proteasome_homologs’). The following data are available at https://data.mendeley.com/datasets/t48yhff7hs/3: (i) sequence alignments for each proteasome-like homolog, (ii) the coordinates for their structural models and (iii) a cluster-map file, which can be navigated interactively in CLANS and gives direct access to all the sequences in this study. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Adrian C D Fuchs
- Department of Protein Evolution, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Vikram Alva
- Department of Protein Evolution, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Andrei N Lupas
- Department of Protein Evolution, Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
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24
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Somma V, Calvio C, Rabuffetti M, Rama E, Speranza G, Morelli CF. An overall framework for the E. coli γ-glutamyltransferase-catalyzed transpeptidation reactions. Bioorg Chem 2021; 115:105217. [PMID: 34364051 DOI: 10.1016/j.bioorg.2021.105217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 07/16/2021] [Accepted: 07/24/2021] [Indexed: 10/20/2022]
Abstract
γ-Glutamyl derivatives of proteinogenic or modified amino acids raise considerable interest as flavor enhancers or biologically active compounds. However, their supply, on a large scale and at reasonable costs, remains challenging. Enzymatic synthesis has been recognized as a possible affordable alternative with respect to both isolation procedures from natural sources, burdened by low-yield and by the requirement of massive amount of starting material, and chemical synthesis, inconvenient because of the need of protection/deprotection steps. The E. coli γ-glutamyltransferase (Ec-GGT) has already been proposed as a biocatalyst for the synthesis of various γ-glutamyl derivatives. However, enzymatic syntheses using this enzyme usually provide the desired products in limited yield. Hydrolysis and autotranspeptidation of the donor substrate have been identified as the side reactions affecting the final yield of the catalytic process. In addition, experimental conditions need to be specifically adjusted for each acceptor substrate. Substrate specificity and the fine characterization of the activities exerted by the enzyme over time has so far escaped rationalization. In this work, reactions catalyzed by Ec-GGT between the γ-glutamyl donor glutamine and several representative acceptor amino acids have been finely analyzed with the identification of single reaction products over time. This approach allowed to rationalize the effect of donor/acceptor molar ratio on the outcome of the transpeptidation reaction and on the distribution of the different byproducts, inferring a general scheme for Ec-GGT-catalyzed reactions. The propensity to react of the different acceptor substrates is in agreement with recent findings obtained using model substrates and further supported by x-ray crystallography and will contribute to characterize the still elusive acceptor binding site of the enzyme.
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Affiliation(s)
- Valeria Somma
- Department of Chemistry, Università degli Studi di Milano, via Golgi, 19, 20133 Milano, Italy.
| | - Cinzia Calvio
- Department of Biology and Biotechnology, Università degli Studi di Pavia, via Ferrata, 9, 27100 Pavia, Italy.
| | - Marco Rabuffetti
- Department of Chemistry, Università degli Studi di Milano, via Golgi, 19, 20133 Milano, Italy.
| | - Erlinda Rama
- Department of Biology and Biotechnology, Università degli Studi di Pavia, via Ferrata, 9, 27100 Pavia, Italy.
| | - Giovanna Speranza
- Department of Chemistry, Università degli Studi di Milano, via Golgi, 19, 20133 Milano, Italy.
| | - Carlo F Morelli
- Department of Chemistry, Università degli Studi di Milano, via Golgi, 19, 20133 Milano, Italy.
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25
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Ghidini A, Scalvini L, Palese F, Lodola A, Mor M, Piomelli D. Different roles for the acyl chain and the amine leaving group in the substrate selectivity of N-Acylethanolamine acid amidase. J Enzyme Inhib Med Chem 2021; 36:1411-1423. [PMID: 34256657 PMCID: PMC8279155 DOI: 10.1080/14756366.2021.1912035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
N-acylethanolamine acid amidase (NAAA) is an N-terminal nucleophile (Ntn) hydrolase that catalyses the intracellular deactivation of the endogenous analgesic and anti-inflammatory agent palmitoylethanolamide (PEA). NAAA inhibitors counteract this process and exert marked therapeutic effects in animal models of pain, inflammation and neurodegeneration. While it is known that NAAA preferentially hydrolyses saturated fatty acid ethanolamides (FAEs), a detailed profile of the relationship between catalytic efficiency and fatty acid-chain length is still lacking. In this report, we combined enzymatic and molecular modelling approaches to determine the effects of acyl chain and polar head modifications on substrate recognition and hydrolysis by NAAA. The results show that, in both saturated and monounsaturated FAEs, the catalytic efficiency is strictly dependent upon fatty acyl chain length, whereas there is a wider tolerance for modifications of the polar heads. This relationship reflects the relative stability of enzyme-substrate complexes in molecular dynamics simulations.
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Affiliation(s)
- Andrea Ghidini
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parma, Italy
| | - Laura Scalvini
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parma, Italy
| | - Francesca Palese
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, USA
| | - Alessio Lodola
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parma, Italy
| | - Marco Mor
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parma, Italy
| | - Daniele Piomelli
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, USA.,Department of Pharmaceutical Sciences, University of California, Irvine, CA, USA.,Department of Biological Chemistry and Molecular Biology, University of California, Irvine, CA, USA
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26
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Loch JI, Jaskolski M. Structural and biophysical aspects of l-asparaginases: a growing family with amazing diversity. IUCRJ 2021; 8:514-531. [PMID: 34258001 PMCID: PMC8256714 DOI: 10.1107/s2052252521006011] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 06/09/2021] [Indexed: 06/13/2023]
Abstract
l-Asparaginases have remained an intriguing research topic since their discovery ∼120 years ago, especially after their introduction in the 1960s as very efficient antileukemic drugs. In addition to bacterial asparaginases, which are still used to treat childhood leukemia, enzymes of plant and mammalian origin are now also known. They have all been structurally characterized by crystallography, in some cases at outstanding resolution. The structural data have also shed light on the mechanistic details of these deceptively simple enzymes. Yet, despite all this progress, no better therapeutic agents have been found to beat bacterial asparaginases. However, a new option might arise with the discovery of yet another type of asparaginase, those from symbiotic nitrogen-fixing Rhizobia, and with progress in the protein engineering of enzymes with desired properties. This review surveys the field of structural biology of l-asparaginases, focusing on the mechanistic aspects of the well established types and speculating about the potential of the new members of this amazingly diversified family.
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Affiliation(s)
- Joanna I. Loch
- Department of Crystal Chemistry and Crystal Physics, Faculty of Chemistry, Jagiellonian University, Cracow, Poland
| | - Mariusz Jaskolski
- Department of Crystallography, Faculty of Chemistry, A. Mickiewicz University, Poznan, Poland
- Center for Biocrystallographic Research, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
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27
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Cho HB, Ahn JH, Yang HG, Lee J, Park WJ, Kim YW. Effects of pH and NaCl on hydrolysis and transpeptidation activities of a salt-tolerant γ-glutamyltranspeptidase from Bacillus amyloliquefaciens S0904. Food Sci Biotechnol 2021; 30:853-860. [PMID: 34249391 DOI: 10.1007/s10068-021-00928-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/10/2021] [Accepted: 06/08/2021] [Indexed: 11/30/2022] Open
Abstract
Bacillus amyloliquefaciens S0904 was selected as a hyperproducer of a glutamine-hydrolyzing enzyme which was identified as a γ-glutamyltranspeptidase catalyzing both hydrolysis and transpeptidation of glutamyl substrates. The signal peptide-truncated recombinant enzyme (rBAGGT) showed two-fold enhanced specific activity for hydrolysis and optimum pH shift to pH 7 from pH 6 compared with the wild type. The hydrolysis activity of rBAGGT was tolerant against NaCl up to 2.5 M, whereas the transpeptidation activity decreased by NaCl. At pH 6, the addition of 1.5 M NaCl not only enhanced the hydrolysis activity but also inhibited the transpeptidation activity to be ignorable. By contrast, at pH 9 in the absence of NaCl, the alkaline pH-favored transpeptidation activity was 99% of the maximum with only 15% of the maximum hydrolysis activity. In conclusion, the hydrolysis and transpeptidation activities of the recombinant BAGGT is controllable by changing pH and whether or not to add NaCl. Supplementary Information The online version contains supplementary material available at 10.1007/s10068-021-00928-6.
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Affiliation(s)
- Hye-Bin Cho
- Department of Food and Biotechnology, Korea University, Sejong, 30019 Republic of Korea
| | - Jun-Ho Ahn
- Department of Food and Biotechnology, Korea University, Sejong, 30019 Republic of Korea
| | - Hyeon-Gyu Yang
- Department of Food and Biotechnology, Korea University, Sejong, 30019 Republic of Korea
| | - Jaeick Lee
- Department of Food and Biotechnology, Korea University, Sejong, 30019 Republic of Korea
| | - Wu-Jin Park
- R&D Center, Nongshim Co., Seoul, 07057 Republic of Korea
| | - Young-Wan Kim
- Department of Food and Biotechnology, Korea University, Sejong, 30019 Republic of Korea
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28
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Werner N, Petersen K, Vollstedt C, Garcia PP, Chow J, Ferrer M, Fernandez-Lopez L, Falke S, Perbandt M, Hinrichs W, Betzel C, Streit WR. The Komagataeibacter europaeus GqqA is the prototype of a novel bifunctional N-Acyl-homoserine lactone acylase with prephenate dehydratase activity. Sci Rep 2021; 11:12255. [PMID: 34112823 PMCID: PMC8192741 DOI: 10.1038/s41598-021-91536-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 05/24/2021] [Indexed: 11/09/2022] Open
Abstract
Previously, we reported the isolation of a quorum quenching protein (QQ), designated GqqA, from Komagataeibacter europaeus CECT 8546 that is highly homologous to prephenate dehydratases (PDT) (Valera et al. in Microb Cell Fact 15, 88. https://doi.org/10.1186/s12934-016-0482-y , 2016). GqqA strongly interfered with N-acyl-homoserine lactone (AHL) quorum sensing signals from Gram-negative bacteria and affected biofilm formation in its native host strain Komagataeibacter europaeus. Here we present and discuss data identifying GqqA as a novel acylase. ESI-MS-MS data showed unambiguously that GqqA hydrolyzes the amide bond of the acyl side-chain of AHL molecules, but not the lactone ring. Consistent with this observation the protein sequence does not carry a conserved Zn2+ binding motif, known to be essential for metal-dependent lactonases, but in fact harboring the typical periplasmatic binding protein domain (PBP domain), acting as catalytic domain. We report structural details for the native structure at 2.5 Å resolution and for a truncated GqqA structure at 1.7 Å. The structures obtained highlight that GqqA acts as a dimer and complementary docking studies indicate that the lactone ring of the substrate binds within a cleft of the PBP domain and interacts with polar residues Y16, S17 and T174. The biochemical and phylogenetic analyses imply that GqqA represents the first member of a novel type of QQ family enzymes.
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Affiliation(s)
- Nadine Werner
- Laboratory for Structural Biology of Infection and Inflammation, Institute of Biochemistry and Molecular Biology, University Hamburg, C/O DESY, 22607, Hamburg, Germany
| | - Katrin Petersen
- Microbiology and Biotechnology, University Hamburg, 22609, Hamburg, Germany
| | - Christel Vollstedt
- Microbiology and Biotechnology, University Hamburg, 22609, Hamburg, Germany
| | - Pablo Perez Garcia
- Microbiology and Biotechnology, University Hamburg, 22609, Hamburg, Germany
| | - Jennifer Chow
- Microbiology and Biotechnology, University Hamburg, 22609, Hamburg, Germany
| | - Manuel Ferrer
- Institute of Catalysis, Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain
| | - Laura Fernandez-Lopez
- Institute of Catalysis, Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain
| | - Sven Falke
- Laboratory for Structural Biology of Infection and Inflammation, Institute of Biochemistry and Molecular Biology, University Hamburg, C/O DESY, 22607, Hamburg, Germany
| | - Markus Perbandt
- Laboratory for Structural Biology of Infection and Inflammation, Institute of Biochemistry and Molecular Biology, University Hamburg, C/O DESY, 22607, Hamburg, Germany
| | - Winfried Hinrichs
- Institute for Biochemistry, University Greifswald, 17487, Greifswald, Germany
| | - Christian Betzel
- Laboratory for Structural Biology of Infection and Inflammation, Institute of Biochemistry and Molecular Biology, University Hamburg, C/O DESY, 22607, Hamburg, Germany.
| | - Wolfgang R Streit
- Microbiology and Biotechnology, University Hamburg, 22609, Hamburg, Germany.
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29
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Bile Salt Hydrolases: At the Crossroads of Microbiota and Human Health. Microorganisms 2021; 9:microorganisms9061122. [PMID: 34067328 PMCID: PMC8224655 DOI: 10.3390/microorganisms9061122] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/16/2021] [Accepted: 05/18/2021] [Indexed: 12/12/2022] Open
Abstract
The gut microbiota has been increasingly linked to metabolic health and disease over the last few decades. Several factors have been suggested to be involved in lipid metabolism and metabolic responses. One mediator that has gained great interest as a clinically important enzyme is bile salt hydrolase (BSH). BSH enzymes are widely distributed in human gastrointestinal microbial communities and are believed to play key roles in both microbial and host physiology. In this review, we discuss the current evidence related to the role of BSHs in health and provide useful insights that may pave the way for new therapeutic targets in human diseases.
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30
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Functional and Phylogenetic Diversity of BSH and PVA Enzymes. Microorganisms 2021; 9:microorganisms9040732. [PMID: 33807488 PMCID: PMC8066178 DOI: 10.3390/microorganisms9040732] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/24/2021] [Accepted: 03/29/2021] [Indexed: 12/12/2022] Open
Abstract
Bile salt hydrolase (BSH) and penicillin V acylase (PVA) are related enzymes that are classified as choloylglycine hydrolases (CGH). BSH enzymes have attracted significant interest for their ability to modulate the composition of the bile acid pool, alter bile acid signaling events mediated by the host bile acid receptors FXR and TGR5 and influence cholesterol homeostasis in the host, while PVA enzymes have been widely utilised in an industrial capacity in the production of semi-synthetic antibiotics. The similarities between BSH and PVA enzymes suggest common evolution of these enzymes and shared mechanisms for substrate binding and catalysis. Here, we compare BSH and PVA through analysis of the distribution, phylogeny and biochemistry of these microbial enzymes. The development of new annotation approaches based upon functional enzyme analyses and the potential implications of BSH enzymes for host health are discussed.
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31
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Nagaratnam N, Delker SL, Jernigan R, Edwards TE, Snider J, Thifault D, Williams D, Nannenga BL, Stofega M, Sambucetti L, Hsieh JJ, Flint AJ, Fromme P, Martin-Garcia JM. Structural insights into the function of the catalytically active human Taspase1. Structure 2021; 29:873-885.e5. [PMID: 33784495 DOI: 10.1016/j.str.2021.03.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 02/07/2021] [Accepted: 03/10/2021] [Indexed: 12/15/2022]
Abstract
Taspase1 is an Ntn-hydrolase overexpressed in primary human cancers, coordinating cancer cell proliferation, invasion, and metastasis. Loss of Taspase1 activity disrupts proliferation of human cancer cells in vitro and in mouse models of glioblastoma. Taspase1 is synthesized as an inactive proenzyme, becoming active upon intramolecular cleavage. The activation process changes the conformation of a long fragment at the C-terminus of the α subunit, for which no full-length structural information exists and whose function is poorly understood. We present a cloning strategy to generate a circularly permuted form of Taspase1 to determine the crystallographic structure of active Taspase1. We discovered that this region forms a long helix and is indispensable for the catalytic activity of Taspase1. Our study highlights the importance of this element for the enzymatic activity of Ntn-hydrolases, suggesting that it could be a potential target for the design of inhibitors with potential to be developed into anticancer therapeutics.
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Affiliation(s)
- Nirupa Nagaratnam
- Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
| | - Silvia L Delker
- Beryllium Discovery Corp., with present address of UCB Biosciences, Bedford, MA 01730, USA
| | - Rebecca Jernigan
- Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
| | - Thomas E Edwards
- Beryllium Discovery Corp., with present address of UCB Biosciences, Bedford, MA 01730, USA
| | - Janey Snider
- Division of Biosciences, SRI International Menlo Park, Menlo Park, CA 94025, USA
| | - Darren Thifault
- Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
| | - Dewight Williams
- Eyring Materials Center, Arizona State University, Tempe, AZ 85257, USA
| | - Brent L Nannenga
- Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA; Chemical Engineering, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ 85287, USA
| | - Mary Stofega
- Division of Biosciences, SRI International Menlo Park, Menlo Park, CA 94025, USA
| | - Lidia Sambucetti
- Division of Biosciences, SRI International Menlo Park, Menlo Park, CA 94025, USA
| | - James J Hsieh
- Molecular Oncology, Division of Oncology, Department of Medicine, Washington University, St. Louis, MO 63110, USA
| | - Andrew J Flint
- Frederick National Lab for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Petra Fromme
- Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA.
| | - Jose M Martin-Garcia
- Center for Applied Structural Discovery, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA; Department of Crystallography and Structural Biology, Institute of Physical-Chemistry "Rocasolano", Spanish National Research Council (CSIC), Madrid 28006, Spain.
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32
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Abstract
The 26S proteasome is the most complex ATP-dependent protease machinery, of ~2.5 MDa mass, ubiquitously found in all eukaryotes. It selectively degrades ubiquitin-conjugated proteins and plays fundamentally indispensable roles in regulating almost all major aspects of cellular activities. To serve as the sole terminal "processor" for myriad ubiquitylation pathways, the proteasome evolved exceptional adaptability in dynamically organizing a large network of proteins, including ubiquitin receptors, shuttle factors, deubiquitinases, AAA-ATPase unfoldases, and ubiquitin ligases, to enable substrate selectivity and processing efficiency and to achieve regulation precision of a vast diversity of substrates. The inner working of the 26S proteasome is among the most sophisticated, enigmatic mechanisms of enzyme machinery in eukaryotic cells. Recent breakthroughs in three-dimensional atomic-level visualization of the 26S proteasome dynamics during polyubiquitylated substrate degradation elucidated an extensively detailed picture of its functional mechanisms, owing to progressive methodological advances associated with cryogenic electron microscopy (cryo-EM). Multiple sites of ubiquitin binding in the proteasome revealed a canonical mode of ubiquitin-dependent substrate engagement. The proteasome conformation in the act of substrate deubiquitylation provided insights into how the deubiquitylating activity of RPN11 is enhanced in the holoenzyme and is coupled to substrate translocation. Intriguingly, three principal modes of coordinated ATP hydrolysis in the heterohexameric AAA-ATPase motor were discovered to regulate intermediate functional steps of the proteasome, including ubiquitin-substrate engagement, deubiquitylation, initiation of substrate translocation and processive substrate degradation. The atomic dissection of the innermost working of the 26S proteasome opens up a new era in our understanding of the ubiquitin-proteasome system and has far-reaching implications in health and disease.
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Affiliation(s)
- Youdong Mao
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, 02215, Massachusetts, USA. .,School of Physics, Center for Quantitative Biology, Peking University, Beijing, 100871, China.
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33
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Oliva F, Flores-Canales JC, Pieraccini S, Morelli CF, Sironi M, Schiøtt B. Simulating Multiple Substrate-Binding Events by γ-Glutamyltransferase Using Accelerated Molecular Dynamics. J Phys Chem B 2020; 124:10104-10116. [PMID: 33112625 DOI: 10.1021/acs.jpcb.0c06907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
γ-Glutamyltransferase (GGT) is an enzyme that uses γ-glutamyl compounds as substrates and catalyzes their transfer to a water molecule or an acceptor substrate with varied physiological function in bacteria, plants, and animals. Crystal structures of GGT are known for different species and in different states of the chemical reaction; however, the structural dynamics of the substrate binding to the catalytic site of GGT are unknown. Here, we modeled Escherichia coli GGT's glutamine binding by using a swarm of accelerated molecular dynamics (aMD) simulations. Characterization of multiple binding events identified three structural binding motifs composed of polar residues in the binding pocket that govern glutamine binding into the active site. Simulated open and closed conformations of a lid-loop protecting the binding cavity suggest its role as a gating element by allowing or blocking substrates entry into the binding pocket. Partially open states of the lid-loop are accessible within thermal fluctuations, while the estimated free energy cost of a complete open state is 2.4 kcal/mol. Our results suggest that both specific electrostatic interactions and GGT conformational dynamics dictate the molecular recognition of substrate-GGT complexes.
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Affiliation(s)
- Francesco Oliva
- Dipartimento di Chimica, Università degli studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Jose C Flores-Canales
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus, Denmark
| | - Stefano Pieraccini
- Dipartimento di Chimica, Università degli studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Carlo F Morelli
- Dipartimento di Chimica, Università degli studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Maurizio Sironi
- Dipartimento di Chimica, Università degli studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Birgit Schiøtt
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus, Denmark
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34
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Sveistyte A, Gibbins T, Tyrrell KJ, Miller CJ, Foley MH, Plymale AE, Wright AT, Brandvold KR. Simple Analysis of Primary and Secondary Bile Salt Hydrolysis in Mouse and Human Gut Microbiome Samples by Using Fluorogenic Substrates. Chembiochem 2020; 21:3539-3543. [PMID: 32761683 DOI: 10.1002/cbic.202000370] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/03/2020] [Indexed: 12/13/2022]
Abstract
Animals produce bile to act as an antibacterial agent and to maximize the absorption of lipophilic nutrients in the gut. The physical properties of bile are largely dictated by amphipathic bile salt molecules, which also participate in signaling pathways by modulating physiological processes upon binding host receptors. Upon excretion of bile salts from the gall bladder into the intestine, the gut microbiota can create metabolites with modified signaling capabilities. The category and magnitude of bile salt metabolism can have positive or negative effects on the host. A key modification is bile salt hydrolysis, which is a prerequisite for all additional microbial transformations. We have synthesized five different fluorogenic bile salts for simple and continuous reporting of hydrolysis in both murine and human fecal samples. Our data demonstrate that most gut microbiomes have the highest capacity for hydrolysis of host-produced primary bile salts, but some microbially modified secondary bile salts also display significant turnover.
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Affiliation(s)
- Agne Sveistyte
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Teresa Gibbins
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Kimberly J Tyrrell
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Carson J Miller
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Matt H Foley
- NC State Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
| | - Andrew E Plymale
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Aaron T Wright
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.,The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99163, USA
| | - Kristoffer R Brandvold
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.,Elson S. Floyd College of Medicine, Washington State University, Spokane, WA 99202, USA
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Scalvini L, Ghidini A, Lodola A, Callegari D, Rivara S, Piomelli D, Mor M. N-Acylethanolamine Acid Amidase (NAAA): Mechanism of Palmitoylethanolamide Hydrolysis Revealed by Mechanistic Simulations. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02903] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Laura Scalvini
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle scienze 27/A, I-43124 Parma, Italy
| | - Andrea Ghidini
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle scienze 27/A, I-43124 Parma, Italy
| | - Alessio Lodola
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle scienze 27/A, I-43124 Parma, Italy
| | - Donatella Callegari
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle scienze 27/A, I-43124 Parma, Italy
| | - Silvia Rivara
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle scienze 27/A, I-43124 Parma, Italy
| | - Daniele Piomelli
- Department of Anatomy and Neurobiology, University of California, Irvine, California 92697-4625, United States
- Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-4625, United States
- Department of Biological Chemistry and Molecular Biology, University of California, Irvine, California 92697-4625, United States
| | - Marco Mor
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle scienze 27/A, I-43124 Parma, Italy
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36
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Garrido-González JJ, Iglesias Aparicio MM, García MM, Simón L, Sanz F, Morán JR, Fuentes de Arriba ÁL. An Enzyme Model Which Mimics Chymotrypsin and N-Terminal Hydrolases. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02121] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- José J. Garrido-González
- Organic Chemistry Department, University of Salamanca, Plaza de los Caídos 1-5, Salamanca E-37008, Spain
| | | | - Miguel Martínez García
- Organic Chemistry Department, University of Salamanca, Plaza de los Caídos 1-5, Salamanca E-37008, Spain
| | - Luis Simón
- Chemical Engineering Department, University of Salamanca, Plaza de los Caídos 1-5, Salamanca E-37008, Spain
| | - Francisca Sanz
- X-Ray Diffraction Service, University of Salamanca, Plaza de los Caídos 1-5, Salamanca E-37008, Spain
| | - Joaquín R. Morán
- Organic Chemistry Department, University of Salamanca, Plaza de los Caídos 1-5, Salamanca E-37008, Spain
| | - Ángel L. Fuentes de Arriba
- Organic Chemistry Department, University of Salamanca, Plaza de los Caídos 1-5, Salamanca E-37008, Spain
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Structural and enzymatic analysis of a dimeric cholylglycine hydrolase like acylase active on N-acyl homoserine lactones. Biochimie 2020; 177:108-116. [PMID: 32835734 DOI: 10.1016/j.biochi.2020.07.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 07/24/2020] [Accepted: 07/26/2020] [Indexed: 01/17/2023]
Abstract
The prevalence of substrate cross-reactivity between AHL acylases and β-lactam acylases provides a glimpse of probable links between quorum sensing and antibiotic resistance in bacteria. Both these enzyme classes belong to the N-terminal nucleophile (Ntn)-hydrolase superfamily. Penicillin V acylases alongside bile salt hydrolases constitute the cholylglycine hydrolase (CGH) group of the Ntn-hydrolase superfamily. Here we report the ability of two acylases, Slac1 and Slac2, from the marine bacterium Shewanella loihica-PV4 to hydrolyze AHLs. Three-dimensional structure of Slac1reveals the conservation of the Ntn hydrolase fold and CGH active site, making it a unique CGH exclusively active on AHLs. Slac1homologs phylogenetically cluster separate from reported CGHs and AHL acylases, thereby representing a functionally distinct sub-class of CGH that might have evolved as an adaptation to the marine environment. We hypothesize that Slac1 could provide the structural framework for understanding this subclass, and further our understanding of the evolutionary link between AHL acylases and β-lactam acylases.
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38
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Ullah A, Masood R. The Sequence and Three-Dimensional Structure Characterization of Snake Venom Phospholipases B. Front Mol Biosci 2020; 7:175. [PMID: 32850964 PMCID: PMC7419708 DOI: 10.3389/fmolb.2020.00175] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 07/06/2020] [Indexed: 11/23/2022] Open
Abstract
Snake venom phospholipases B (SVPLBs) are the least studied enzymes. They constitute about 1% of Bothrops crude venoms, however, in other snake venoms, it is present in less than 1%. These enzymes are considered the most potent hemolytic agent in the venom. Currently, no structural information is available about these enzymes from snake venom. To better understand its three-dimensional structure and mechanisms of envenomation, the current work describes the first model-based structure report of this enzyme from Bothrops moojeni venom named as B. moojeni phospholipase B (PLB_Bm). The structure model of PLB_Bm was generated using model building software like I-TESSER, MODELLER 9v19, and Swiss-Model. The build PLB_Bm model was validated using validation tools (PROCHECK, ERRAT, and Verif3D). The analysis of the PLB_Bm modeled structure indicates that it contains 491 amino acid residues that form a well-defined four-layer αββα sandwich core and has a typical fold of the N-terminal nucleophile aminohydrolase (Ntn-hydrolase). The overall structure of PLB_Bm contains 18 β-strands and 17 α-helices with many connecting loops. The structure divides into two chains (A and B) after maturation. The A chain is smaller and contains 207 amino acid residues, whereas the B chain is larger and contains 266 amino acid residues. The sequence and structural comparison among homologous snake venom, bacterial, and mammals PLBs indicate that differences in the length and sequence composition may confer variable substrate specificity to these enzymes. Moreover, the surface charge distribution, average volume, and depth of the active site cavity also vary in these enzymes. The present work will provide more information about the structure-function relationship and mechanism of action of these enzymes in snakebite envenomation.
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Affiliation(s)
- Anwar Ullah
- Department of Biosciences, COMSATS University Islamabad, Islamabad, Pakistan
| | - Rehana Masood
- Department of Biochemistry, Shaheed Benazir Bhutto Women University Peshawar, Peshawar, Pakistan
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39
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Biringer RG. The enzymology of human eicosanoid pathways: the lipoxygenase branches. Mol Biol Rep 2020; 47:7189-7207. [PMID: 32748021 DOI: 10.1007/s11033-020-05698-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 07/26/2020] [Indexed: 12/16/2022]
Abstract
Eicosanoids are short-lived derivatives of polyunsaturated fatty acids that serve as autocrine and paracrine signaling molecules. They are involved numerous biological processes of both the well state and disease states. A thorough understanding of the progression the disease state and homeostasis of the well state requires a complete evaluation of the systems involved. This review examines the enzymology for the enzymes involved in the production of eicosanoids along the lipoxygenase branches of the eicosanoid pathways with particular emphasis on those derived from arachidonic acid. The enzymatic parameters, protocols to measure them, and proposed catalytic mechanisms are presented in detail.
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Affiliation(s)
- Roger Gregory Biringer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, FL, 34211, USA.
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40
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Kang XM, Cai X, Liu ZQ, Zheng YG. Secretory expression and characterization of a novel amidase from Kluyvera cryocrescens in Bacillus subtilis. Biotechnol Lett 2020; 42:2367-2377. [DOI: 10.1007/s10529-020-02959-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 01/08/2020] [Indexed: 10/23/2022]
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41
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Penicillin Acylase from Streptomyces lavendulae and Aculeacin A Acylase from Actinoplanes utahensis: Two Versatile Enzymes as Useful Tools for Quorum Quenching Processes. Catalysts 2020. [DOI: 10.3390/catal10070730] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Many Gram-negative bacteria produce N-acyl-homoserine lactones (AHLs), quorum sensing (QS) molecules that can be enzymatically inactivated by quorum quenching (QQ) processes; this approach is considered an emerging antimicrobial alternative. In this study, kinetic parameters of several AHLs hydrolyzed by penicillin acylase from Streptomyces lavendulae (SlPA) and aculeacin A acylase from Actinoplanes utahensis (AuAAC) have been determined. Both enzymes catalyze efficiently the amide bond hydrolysis in AHLs with different acyl chain moieties (with or without 3-oxo modification) and exhibit a clear preference for AHLs with long acyl chains (C12-HSL > C14-HSL > C10-HSL > C8-HSL for SlPA, whereas C14-HSL > C12-HSL > C10-HSL > C8-HSL for AuAAC). Involvement of SlPA and AuAAC in QQ processes was demonstrated by Chromobacterium violaceum CV026-based bioassays and inhibition of biofilm formation by Pseudomonas aeruginosa, a process controlled by QS molecules, suggesting the application of these multifunctional enzymes as quorum quenching agents, this being the first time that quorum quenching activity was shown by an aculeacin A acylase. In addition, a phylogenetic study suggests that SlPA and AuAAC could be part of a new family of actinomycete acylases, with a preference for substrates with long aliphatic acyl chains, and likely involved in QQ processes.
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42
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Piomelli D, Scalvini L, Fotio Y, Lodola A, Spadoni G, Tarzia G, Mor M. N-Acylethanolamine Acid Amidase (NAAA): Structure, Function, and Inhibition. J Med Chem 2020; 63:7475-7490. [PMID: 32191459 DOI: 10.1021/acs.jmedchem.0c00191] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
N-Acylethanolamine acid amidase (NAAA) is an N-terminal cysteine hydrolase primarily found in the endosomal-lysosomal compartment of innate and adaptive immune cells. NAAA catalyzes the hydrolytic deactivation of palmitoylethanolamide (PEA), a lipid-derived peroxisome proliferator-activated receptor-α (PPAR-α) agonist that exerts profound anti-inflammatory effects in animal models. Emerging evidence points to NAAA-regulated PEA signaling at PPAR-α as a critical control point for the induction and the resolution of inflammation and to NAAA itself as a target for anti-inflammatory medicines. The present Perspective discusses three key aspects of this hypothesis: the role of NAAA in controlling the signaling activity of PEA; the structural bases for NAAA function and inhibition by covalent and noncovalent agents; and finally, the potential value of NAAA-targeting drugs in the treatment of human inflammatory disorders.
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Affiliation(s)
- Daniele Piomelli
- Department of Anatomy and Neurobiology, University of California, Irvine, California 92697-4625, United States.,Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-4625, United States.,Department of Biological Chemistry and Molecular Biology, University of California, Irvine, California 92697-4625, United States
| | - Laura Scalvini
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle Scienze 27/A, I- 43124 Parma, Italy
| | - Yannick Fotio
- Department of Anatomy and Neurobiology, University of California, Irvine, California 92697-4625, United States
| | - Alessio Lodola
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle Scienze 27/A, I- 43124 Parma, Italy
| | - Gilberto Spadoni
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino "Carlo Bo", Piazza Rinascimento 6, I-61029 Urbino, Italy
| | - Giorgio Tarzia
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino "Carlo Bo", Piazza Rinascimento 6, I-61029 Urbino, Italy
| | - Marco Mor
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli Studi di Parma, Parco Area delle Scienze 27/A, I- 43124 Parma, Italy
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Abstract
The mercapturic acid pathway is a major route for the biotransformation of xenobiotic and endobiotic electrophilic compounds and their metabolites. Mercapturic acids (N-acetyl-l-cysteine S-conjugates) are formed by the sequential action of the glutathione transferases, γ-glutamyltransferases, dipeptidases, and cysteine S-conjugate N-acetyltransferase to yield glutathione S-conjugates, l-cysteinylglycine S-conjugates, l-cysteine S-conjugates, and mercapturic acids; these metabolites constitute a "mercapturomic" profile. Aminoacylases catalyze the hydrolysis of mercapturic acids to form cysteine S-conjugates. Several renal transport systems facilitate the urinary elimination of mercapturic acids; urinary mercapturic acids may serve as biomarkers for exposure to chemicals. Although mercapturic acid formation and elimination is a detoxication reaction, l-cysteine S-conjugates may undergo bioactivation by cysteine S-conjugate β-lyase. Moreover, some l-cysteine S-conjugates, particularly l-cysteinyl-leukotrienes, exert significant pathophysiological effects. Finally, some enzymes of the mercapturic acid pathway are described as the so-called "moonlighting proteins," catalytic proteins that exert multiple biochemical or biophysical functions apart from catalysis.
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Affiliation(s)
- Patrick E Hanna
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - M W Anders
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY, USA
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44
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Abstract
Natural nonproteinogenic amino acids vastly outnumber the well-known 22 proteinogenic amino acids. Such amino acids are generated in specialized metabolic pathways. In these pathways, diverse biosynthetic transformations, ranging from isomerizations to the stereospecific functionalization of C-H bonds, are employed to generate structural diversity. The resulting nonproteinogenic amino acids can be integrated into more complex natural products. Here we review recently discovered biosynthetic routes to freestanding nonproteinogenic α-amino acids, with an emphasis on work reported between 2013 and mid-2019.
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Affiliation(s)
- Jason B Hedges
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Katherine S Ryan
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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45
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Rawlings ND. Twenty-five years of nomenclature and classification of proteolytic enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1868:140345. [PMID: 31838087 DOI: 10.1016/j.bbapap.2019.140345] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/09/2019] [Accepted: 12/11/2019] [Indexed: 10/25/2022]
Abstract
Proteolytic enzymes and their homologues have been classified into clans by comparing the tertiary structures of the peptidase domains, into families by comparing the protein sequences of the peptidase domains, and into protein-species by comparing various attributes including domain architecture, substrate preference, inhibitor interactions, subcellular location, and phylogeny. The results are compared with the earlier classification (Rawlings and Barrett, 1993 [1]). The numbers of sequences, protein-species, families, clans and even catalytic type have substantially increased during the intervening 26 years. The alternative classifications by catalytic type and/or activity are shown not to reflect evolutionary relationships.
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Affiliation(s)
- Neil D Rawlings
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire CB10 1SD, UK.
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46
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Kaur T, Balgir PP, Kaur B. Construction of a shuttle expression vector for lactic acid bacteria. J Genet Eng Biotechnol 2019; 17:10. [PMID: 31736018 PMCID: PMC6859148 DOI: 10.1186/s43141-019-0013-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Accepted: 10/02/2019] [Indexed: 12/12/2022]
Abstract
Background Lactic acid bacteria (LAB) are a diverse group of Gram-positive bacteria, which are widely distributed in various diverse natural habitats. These are used in a variety of industrial food fermentations and carry numerous traits with utmost relevance to the food industry. Genetic engineering has emerged as an effective means to improve and enhance the potential of commercially important bacterial strains. However, the biosafety of recombinant systems is an important concern during the implementation of such technologies on an industrial scale. In order to overcome this issue, cloning and expression systems have been developed preferably from fully characterized and annotated LAB plasmids encoding genes with known functions. Results The developed shuttle vector pPBT-GFP contains two theta-type replicons with a copy number of 4.4 and 2.8 in Pediococcus acidilactici MTCC 5101 and Lactobacillus brevis MTCC 1750, respectively. Antimicrobial “pediocin” produced by P. acidilactici MTCC 5101 and green fluorescent protein (GFP) of Aequorea victoria were successfully expressed as selectable markers. Heterologous bile salt hydrolase (BSH) from Lactobacillus fermentum NCDO 394 has been efficiently expressed in the host strains showing high specific activity of 126.12 ± 10.62 in P. acidilactici MTCC 5101 and 95.43 ± 4.26 in the case of L. brevis MTCC 1750, towards glycine-conjugated bile salts preferably as compared to taurine-conjugated salts. Conclusion The present article details the development of a LAB/LAB shuttle expression vector pPBT-GFP, capable of replication in LAB hosts, P. acidilactici MTCC 5101, and L. brevis MTCC 1750. Pediocin and GFP have been used as selectable markers with the efficient production of heterologous extracellular bile salt hydrolase. Thus, the constructed vector pPBT-GFP, with its ability to replicate in multiple hosts, low copy number, and stability in host cells, may serve as an ideal tool for improving LAB strains of commercial value using genetic engineering.
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Affiliation(s)
- Tejinder Kaur
- Department of Biotechnology, Punjabi University, Patiala, 147002, India.
| | - Praveen P Balgir
- Department of Biotechnology, Punjabi University, Patiala, 147002, India
| | - Baljinder Kaur
- Department of Biotechnology, Punjabi University, Patiala, 147002, India
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47
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Mutational Analysis of a Highly Conserved PLSSMXP Sequence in the Small Subunit of Bacillus licheniformis γ-Glutamyltranspeptidase. Biomolecules 2019; 9:biom9090508. [PMID: 31546955 PMCID: PMC6769717 DOI: 10.3390/biom9090508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 01/13/2023] Open
Abstract
A highly conserved 458PLSSMXP464 sequence in the small subunit (S-subunit) of an industrially important Bacillus licheniformis γ-glutamyltranspeptidase (BlGGT) was identified by sequence alignment. Molecular structures of the precursor mimic and the mature form of BlGGT clearly reveal that this peptide sequence is in close spatial proximity to the self-processing and catalytic sites of the enzyme. To probe the role of this conserved sequence, ten mutant enzymes of BlGGT were created through a series of deletion and alanine-scanning mutagenesis. SDS-PAGE and densitometric analyses showed that the intrinsic ability of BlGGT to undergo autocatalytic processing was detrimentally affected by the deletion-associated mutations. However, loss of self-activating capacity was not obviously observed in most of the Ala-replacement mutants. The Ala-replacement mutants had a specific activity comparable to or greater than that of the wild-type enzyme; conversely, all deletion mutants completely lost their enzymatic activity. As compared with BlGGT, S460A and S461S showed greatly enhanced kcat/Km values by 2.73- and 2.67-fold, respectively. The intrinsic tryptophan fluorescence and circular dichroism spectral profiles of Ala-replacement and deletion mutants were typically similar to those of BlGGT. However, heat and guanidine hydrochloride-induced unfolding transitions of the deletion-associated mutant proteins were severely reduced as compared with the wild-type enzyme. The predictive mutant models suggest that the microenvironments required for both self-activation and catalytic reaction of BlGGT can be altered upon mutations.
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Singh J, Metrani R, Shivanagoudra SR, Jayaprakasha GK, Patil BS. Review on Bile Acids: Effects of the Gut Microbiome, Interactions with Dietary Fiber, and Alterations in the Bioaccessibility of Bioactive Compounds. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:9124-9138. [PMID: 30969768 DOI: 10.1021/acs.jafc.8b07306] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Bile acids are cholesterol-derived steroid molecules that serve various metabolic functions, particularly in the digestion of lipids. Gut microbes produce unconjugated and secondary bile acids through deconjugation and dehydroxylation reactions, respectively. Alterations in the gut microbiota have profound effects on bile acid metabolism, which can result in the development of gastrointestinal and metabolic diseases. Emerging research shows that diets rich in dietary fiber have substantial effects on the microbiota and human health. Plant-based foods are primary sources of bioactive compounds and dietary fiber, which are metabolized by microbes to produce different metabolites. However, the bioaccessibility of these compounds are not well-defined. In this review, we discuss the interaction of bile acids with dietary fiber, the gut microbiota, and their role in the bioaccessibility of bioactive compounds. To understand the possible mechanism by which bile acids bind fiber, molecular docking was performed between different dietary fiber and bile salts.
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Affiliation(s)
- Jashbir Singh
- Vegetable and Fruit Improvement Center, Department of Horticultural Sciences , Texas A&M University , 1500 Research Parkway , Suite A120, College Station , Texas 77845 , United States
| | - Rita Metrani
- Vegetable and Fruit Improvement Center, Department of Horticultural Sciences , Texas A&M University , 1500 Research Parkway , Suite A120, College Station , Texas 77845 , United States
| | - Siddanagouda R Shivanagoudra
- Vegetable and Fruit Improvement Center, Department of Horticultural Sciences , Texas A&M University , 1500 Research Parkway , Suite A120, College Station , Texas 77845 , United States
| | - Guddadarangavvanahally K Jayaprakasha
- Vegetable and Fruit Improvement Center, Department of Horticultural Sciences , Texas A&M University , 1500 Research Parkway , Suite A120, College Station , Texas 77845 , United States
| | - Bhimanagouda S Patil
- Vegetable and Fruit Improvement Center, Department of Horticultural Sciences , Texas A&M University , 1500 Research Parkway , Suite A120, College Station , Texas 77845 , United States
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49
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John-White M, Gardiner J, Johanesen P, Lyras D, Dumsday G. β-Aminopeptidases: Insight into Enzymes without a Known Natural Substrate. Appl Environ Microbiol 2019; 85:e00318-19. [PMID: 31126950 PMCID: PMC6643246 DOI: 10.1128/aem.00318-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 05/08/2019] [Indexed: 02/05/2023] Open
Abstract
β-Aminopeptidases have the unique capability to hydrolyze N-terminal β-amino acids, with varied preferences for the nature of β-amino acid side chains. This unique capability makes them useful as biocatalysts for synthesis of β-peptides and to kinetically resolve β-peptides and amides for the production of enantiopure β-amino acids. To date, six β-aminopeptidases have been discovered and functionally characterized, five from Gram-negative bacteria and one from a fungus, Aspergillus Here we report on the purification and characterization of an additional four β-aminopeptidases, one from a Gram-positive bacterium, Mycolicibacterium smegmatis (BapAMs), one from a yeast, Yarrowia lipolytica (BapAYlip), and two from Gram-negative bacteria isolated from activated sludge identified as Burkholderia spp. (BapABcA5 and BapABcC1). The genes encoding β-aminopeptidases were cloned, expressed in Escherichia coli, and purified. The β-aminopeptidases were produced as inactive preproteins that underwent self-cleavage to form active enzymes comprised of two different subunits. The subunits, designated α and β, appeared to be tightly associated, as the active enzyme was recovered after immobilized-metal affinity chromatography (IMAC) purification, even though only the α-subunit was 6-histidine tagged. The enzymes were shown to hydrolyze chromogenic substrates with the N-terminal l-configurations β-homo-Gly (βhGly) and β3-homo-Leu (β3hLeu) with high activities. These enzymes displayed higher activity with H-βhGly-p-nitroanilide (H-βhGly-pNA) than previously characterized enzymes from other microorganisms. These data indicate that the new β-aminopeptidases are fully functional, adding to the toolbox of enzymes that could be used to produce β-peptides. Overexpression studies in Pseudomonas aeruginosa also showed that the β-aminopeptidases may play a role in some cellular functions.IMPORTANCE β-Aminopeptidases are unique enzymes found in a diverse range of microorganisms that can utilize synthetic β-peptides as a sole carbon source. Six β-aminopeptidases have been previously characterized with preferences for different β-amino acid substrates and have demonstrated the capability to catalyze not only the degradation of synthetic β-peptides but also the synthesis of short β-peptides. Identification of other β-aminopeptidases adds to this toolbox of enzymes with differing β-amino acid substrate preferences and kinetics. These enzymes have the potential to be utilized in the sustainable manufacture of β-amino acid derivatives and β-peptides for use in biomedical and biomaterial applications. This is important, because β-amino acids and β-peptides confer increased proteolytic resistance to bioactive compounds and form novel structures as well as structures similar to α-peptides. The discovery of new enzymes will also provide insight into the biological importance of these enzymes in nature.
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Affiliation(s)
- Marietta John-White
- CSIRO Manufacturing, Clayton, Victoria, Australia
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | | | - Priscilla Johanesen
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Dena Lyras
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
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50
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Asparagine 79 is an important amino acid for catalytic activity and substrate specificity of bile salt hydrolase (BSH). Mol Biol Rep 2019; 46:4361-4368. [PMID: 31154605 DOI: 10.1007/s11033-019-04889-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 05/16/2019] [Indexed: 10/26/2022]
Abstract
Microbial bile salt hydrolases (BSHs), a member of cholylglycine hydrolase (CGH) family, catalyze the hydrolysis of glycine and taurine-linked bile salts in the small intestine of human. BSH is evolutionarily related to penicillin V acylase (PVA) which hydrolyses a penicillin V and is also a member of CGH family. Although, five of the six amino acids, C2, R16, D19, N170, N79 and R223, supposed to be responsible for catalytic activity of BSH enzyme, are strictly conserved in all CGH family members, N79 is partially conserved in this family. In this study, in order to analyze the correlation between N79 and catalytic activity or substrate specificity of BSH, the polar and acidic N79 was substituted for the aliphatic and hydrophobic V79 by PCR-based site directed mutagenesis and mutant recombinant BSH was expressed in E. coli BLR(DE3). While the effects of the mutation on catalytic activity and substrate specificity of BSH were detected by ninhydrin assay. The effect of this mutation on the stability of the BSH was observed by SDS-PAGE analysis. Although V79 mutation resulted in stable BSH, it reduced the catalytic activity and altered substrate specificity of BSH. The results suggested that N79 might be important for substrate binding and catalytic turnover of BSH.
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