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Niu X, Zhang J, Xue X, Wang D, Wang L, Gao Q. Deacetoxycephalosporin C synthase (expandase): Research progress and application potential. Synth Syst Biotechnol 2021; 6:396-401. [PMID: 34901478 PMCID: PMC8626558 DOI: 10.1016/j.synbio.2021.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 12/02/2022] Open
Abstract
Cephalosporins play an indispensable role against bacterial infections. Deacetyloxycephalosporin C synthase (DAOCS), also called expandase, is a key enzyme in cephalosporin biosynthesis that epoxides penicillin to form the hexavalent thiazide ring of cephalosporin. DAOCS in fungus Acremonium chrysogenum was identified as a bifunctional enzyme with both ring expansion and hydroxylation, whereas two separate enzymes in bacteria catalyze these two reactions. In this review, we briefly summarize its source and function, improvement of the conversion rate of penicillin to deacetyloxycephalosporin C through enzyme modification, crystallography features, the prediction of the active site, and application perspective.
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Affiliation(s)
- Xiaofan Niu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
| | - Jian Zhang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.,Tianjin Microbial Metabolism and Fermentation Process Control Technology Engineering Center, Tianjin, 300457, China
| | - Xianli Xue
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.,Tianjin Microbial Metabolism and Fermentation Process Control Technology Engineering Center, Tianjin, 300457, China
| | - Depei Wang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.,National Demonstration Center for Experimental Bioengineering Education (Tianjin University of Science and Technology), Tianjin, 300457, China.,Tianjin Microbial Metabolism and Fermentation Process Control Technology Engineering Center, Tianjin, 300457, China
| | - Lin Wang
- College of Artificial Intelligence, Tianjin University of Science and Technology, Tianjin, 300457, China
| | - Qiang Gao
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.,National Demonstration Center for Experimental Bioengineering Education (Tianjin University of Science and Technology), Tianjin, 300457, China.,Tianjin Microbial Metabolism and Fermentation Process Control Technology Engineering Center, Tianjin, 300457, China
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Fan K, Lin B, Tao Y, Yang K. Engineering deacetoxycephalosporin C synthase as a catalyst for the bioconversion of penicillins. J Ind Microbiol Biotechnol 2016; 44:705-710. [PMID: 27826726 DOI: 10.1007/s10295-016-1857-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 10/30/2016] [Indexed: 11/27/2022]
Abstract
7-aminodeacetoxycephalosporanic acid (7-ADCA) is a key intermediate of many clinically useful semisynthetic cephalosporins that were traditionally prepared by processes involving chemical ring expansion of penicillin G. Bioconversion of penicillins to cephalosporins using deacetoxycephalosporin C synthase (DAOCS) is an alternative and environmentally friendly process for 7-ADCA production. Arnold Demain and co-workers pioneered such a process. Later, protein engineering efforts to improve the substrate specificity and catalytic efficiency of DAOCS for penicillins have been made by many groups, and a whole cell process using Escherichia coli for bioconversion of penicillins has been developed.
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Affiliation(s)
- Keqiang Fan
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Beijing, 100101, People's Republic of China
| | - Baixue Lin
- ASCR Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China
| | - Yong Tao
- ASCR Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China
| | - Keqian Yang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Beijing, 100101, People's Republic of China.
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Wu XB, Tian XY, Ji JJ, Wu WB, Fan KQ, Yang KQ. Saturation mutagenesis of Acremonium chrysogenum deacetoxy/deacetylcephalosporin C synthase R308 site confirms its role in controlling substrate specificity. Biotechnol Lett 2010; 33:805-12. [DOI: 10.1007/s10529-010-0504-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 12/08/2010] [Indexed: 11/27/2022]
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Directed evolution and rational approaches to improving Streptomyces clavuligerus deacetoxycephalosporin C synthase for cephalosporin production. J Ind Microbiol Biotechnol 2009; 36:619-33. [DOI: 10.1007/s10295-009-0549-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Accepted: 02/12/2009] [Indexed: 10/21/2022]
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Stok JE, Baldwin JE. Development of enzyme-linked immunosorbent assays for the detection of deacetoxycephalosporin C and isopenicillin N synthase activity. Anal Chim Acta 2006; 577:153-62. [PMID: 17723666 DOI: 10.1016/j.aca.2006.06.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2006] [Revised: 06/13/2006] [Accepted: 06/16/2006] [Indexed: 10/24/2022]
Abstract
Although there are a number of existing assays for monitoring the activity of both isopenicillin N synthase (IPNS) and deacetoxycephalosporin C synthase (DAOCS), none have demonstrated the qualities required for screening a mutant library. Hence, enzyme-linked immunosorbent assays (ELISAs) for IPNS and DAOCS were developed based on the detection of the catalytic turnover products isopenicillin N and cephalexin/phenylacetyl-7-aminodeacetoxycephalosporanic acid (G-7-ADCA), respectively. These assays are relatively fast compared to existing assays, such as the hole-plate bioassay, and are amenable with high-throughput screening. Both the IPNS and DAOCS-ELISAs were optimised for use with crude protein extracts rather than purified protein, thereby eliminating any additional time required for purification. The ELISA developed for the detection of cephalexin had an IC50 value of 154+/-9 ng mL(-1) and LOD of 7.2+/-2.2 ng mL(-1) under conditions required for the assay. Good recoveries and correlation was observed for spiked samples when the concentration of crude protein was kept below 1 mg mL(-1). The DAOCS-ELISA was found to have increased sensitivity compared to the hole-plate bioassay (10.3 microg mL(-1)). The IPNS-ELISA did not significantly increase the sensitivity (approximately 5 microg mL(-1)) compared to that of the hole-plate bioassay (16 microg mL(-1)) for isopenicillin N. The minimum amount of crude protein extract required for producing detectable amounts of product for both assays was below 0.5% of the maximum amount of protein that the assay could contain without any effect on the ELISA. This suggests that when screening a mutant library, mutants producing low amounts of the product could still be detected using these assays.
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Affiliation(s)
- Jeanette E Stok
- Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom.
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Martín JF, Liras P. Enzymes involved in penicillin, cephalosporin and cephamycin biosynthesis. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2006; 39:153-87. [PMID: 2510473 DOI: 10.1007/bfb0051954] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Wu XB, Fan KQ, Wang QH, Yang KQ. C-terminus mutations of Acremonium chrysogenum deacetoxy/deacetylcephalosporin C synthase with improved activity toward penicillin analogs. FEMS Microbiol Lett 2005; 246:103-10. [PMID: 15869968 DOI: 10.1016/j.femsle.2005.03.043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2004] [Revised: 03/16/2005] [Accepted: 03/26/2005] [Indexed: 10/25/2022] Open
Abstract
Deacetoxy/deacetylcephalosporin C synthase (acDAOC/DACS) from Acremonium chrysogenum is a bifunctional enzyme that catalyzes both the ring-expansion of penicillin N to deacetoxycephalosporin C (DAOC) and the hydroxylation of the latter to deacetylcephalosporin C (DAC). Three residues N305, R307 and R308 located in close proximity to the C-terminus of acDAOC/DACS were each mutated to leucine. The N305L and R308L mutant acDAOC/DACSs showed significant improvement in their ability to convert penicillin analogs. R308 was identified for the first time as a critical residue for DAOC/DACS activity. Kinetic analyses of purified R308L enzyme indicated its improved catalytic efficiency is due to combined improvements of K(m) and k(cat). Comparative modeling of acDAOC/DACS supports the involvement of R308 in the formation of substrate-binding pocket.
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Affiliation(s)
- Xiao-Bin Wu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100080, PR China
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Hamilton CS, Yasuhara A, Baldwin JE, Lloyd MD, Rutledge PJ. Contrasting fates for 6-alpha-methylpenicillin N upon oxidation by deacetoxycephalosporin C synthase (DAOCS) and deacetoxy/deacetylcephalosporin C synthase (DAOC/DACS). Bioorg Med Chem Lett 2001; 11:2511-4. [PMID: 11549458 DOI: 10.1016/s0960-894x(01)00470-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
6-alpha-methylpenicillin N was synthesised via known routes from 6-aminopenicillanic acid, and tested as a substrate for recombinant DAOCS and DAOC/DACS. Incubation with DAOCS resulted in conversion of 2-oxoglutarate without oxidation of the penicillin substrate ('uncoupled turnover'). Incubation with DAOC/DACS resulted in oxidation to the cephem aldehyde. This is the first example of substrate-induced 'uncoupled turnover', which has been proposed to be an editing mechanism for these enzymes.
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Affiliation(s)
- C S Hamilton
- The Oxford Centre for Molecular Sciences and The Dyson Perrins Laboratory, South Parks Road, OX1 3QY, Oxford, UK
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Lee HJ, Lloyd MD, Clifton IJ, Harlos K, Dubus A, Baldwin JE, Frere JM, Schofield CJ. Alteration of the co-substrate selectivity of deacetoxycephalosporin C synthase. The role of arginine 258. J Biol Chem 2001; 276:18290-5. [PMID: 11279000 DOI: 10.1074/jbc.m100085200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Deacetoxycephalosporin C synthase is an iron(II) 2-oxoglutaratedependent oxygenase that catalyzes the oxidative ring-expansion of penicillin N to deacetoxycephalosporin C. The wild-type enzyme is only able to efficiently utilize 2-oxoglutarate and 2-oxoadipate as a 2-oxoacid co-substrate. Mutation of arginine 258, the side chain of which forms an electrostatic interaction with the 5-carboxylate of the 2-oxoglutarate co-substrate, to a glutamine residue reduced activity to about 5% of the wild-type enzyme with 2-oxoglutarate. However, other aliphatic 2-oxoacids, which were not co-substrates for the wild-type enzyme, were utilized by the R258Q mutant. These 2-oxoacids "rescued" catalytic activity to the level observed for the wild-type enzyme as judged by penicillin N and G conversion. These co-substrates underwent oxidative decarboxylation as observed for 2-oxoglutarate in the normal reaction with the wild-type enzyme. Crystal structures of the iron(II)- 2-oxo-3-methylbutanoate (1.5 A), and iron(II)-2-oxo-4-methylpentanoate (1.6 A) enzyme complexes were obtained, which reveal the molecular basis for this "chemical co-substrate rescue" and help to rationalize the co-substrate selectivity of 2-oxoglutaratedependent oxygenases.
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Affiliation(s)
- H J Lee
- Oxford Centre for Molecular Sciences and the Dyson Perrins Laboratory, South Parks Road, Oxford OX1 3QY, United Kingdom
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Lee HJ, Lloyd MD, Harlos K, Clifton IJ, Baldwin JE, Schofield CJ. Kinetic and crystallographic studies on deacetoxycephalosporin C synthase (DAOCS). J Mol Biol 2001; 308:937-48. [PMID: 11352583 DOI: 10.1006/jmbi.2001.4649] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Deacetoxycephalosporin C synthase (DAOCS) is an iron(II) and 2-oxoglutarate-dependent oxygenase that catalyzes the conversion of penicillin N to deacetoxycephalosporin C, the committed step in the biosynthesis of cephalosporin antibiotics. The crystal structure of DAOCS revealed that the C terminus of one molecule is inserted into the active site of its neighbor in a cyclical fashion within a trimeric unit. This arrangement has hindered the generation of crystalline enzyme-substrate complexes. Therefore, we constructed a series of DAOCS mutants with modified C termini. Oxidation of 2-oxoglutarate was significantly uncoupled from oxidation of the penicillin substrate in certain truncated mutants. The extent of uncoupling varied with the number of residues deleted and the penicillin substrate used. Crystal structures were determined for the DeltaR306 mutant complexed with iron(II) and 2-oxoglutarate (to 2.10 A) and the DeltaR306A mutant complexed with iron(II), succinate and unhydrated carbon dioxide (to 1.96 A). The latter may mimic a product complex, and supports proposals for a metal-bound CO(2) intermediate during catalysis.
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Affiliation(s)
- H J Lee
- The Oxford Centre for Molecular Sciences and The Dyson Perrins Laboratory, South Parks Road, Oxford, OX1 3QY, UK
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Affiliation(s)
- S E Jensen
- Department of Microbiology, University of Alberta Edmonton, Canada
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Crabbe MC. The effect of thiols and the Ca2+ ionophore A23817 on growth and antibiotic production in Cephalosporium acremonium. FEMS Microbiol Lett 1988. [DOI: 10.1111/j.1574-6968.1988.tb03152.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Baldwin JE, Adlington RM, Coates JB, Crabbe MJ, Crouch NP, Keeping JW, Knight GC, Schofield CJ, Ting HH, Vallejo CA. Purification and initial characterization of an enzyme with deacetoxycephalosporin C synthetase and hydroxylase activities. Biochem J 1987; 245:831-41. [PMID: 3663194 PMCID: PMC1148204 DOI: 10.1042/bj2450831] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Deacetoxycephalosporin C synthetase (expandase) from Cephalosporium acremonium (Acremonium chrysogenum) was purified to near homogeneity as judged by SDS/polyacrylamide-gel electrophoresis. The enzyme (Mr about 40,000) exhibited a pH optimum around 7.5. It required 2-oxoglutarate (Km 0.04 mM), Fe2+ and O2 as cofactors, and ascorbate and dithiothreitol were necessary for maximum activity. It was stable for over 4 weeks at -70 degrees C in the presence of 1 mM-dithiothreitol. Activity was inhibited by the thiol-quenching reagent N-ethylmaleimide, the metal-ion-chelating reagent bathophenanthroline, and NH4HCO3. The highly purified enzyme also showed deacetoxycephalosporin C hydroxylase (deacetylcephalosporin C synthetase) activity, indicating that both expandase and hydroxylase activities are properties of a single protein. These activities could not be separated by ion-exchange, dye-ligand, gel-filtration or hydrophobic chromatography. A beta-sulphoxide and a 3 beta-methylene hydroxy analogue of penicillin N were synthesized to test as potential intermediates in the ring-expansion reaction, Neither compound was a substrate for the enzyme. A synthetic analogue in which the 3 beta-methyl group and the 2-hydrogen atom of penicillin N were replaced by a cyclopropane ring was not a substrate but was a reversible inhibitor of the enzyme.
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Affiliation(s)
- J E Baldwin
- Dyson Perrins Laboratory, University of Oxford, U.K
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