title: One-step elimination of L-cysteine desulfhydrase from crude enzyme extracts of Pseudomonas sp. TS1138 using an immunomagnetic affinity matrix improves the enzymatic production of L-cysteine.
abstract: In this study, a high efficiency immunomagnetic affinity matrix was developed to eliminate L-cysteine desulfhydrase (CD), which decomposes L-cysteine, in crude enzyme extracts from Pseudomonas sp. TS1138. After cloning and expression in Escherichia coli, recombinant CD was purified to raise polyclonal antibodies from mice. The anti-CD antibody was cross-linked to staphylococcal protein A-magnetic cellulose microspheres (MCMS) with dimethyl pimelimidate (DMP). The natural CD was eliminated from the crude enzyme extracts by treatment with the cross-linked antibody-protein A-MCMS, resulting in a high level of L-cysteine production. The conversion rate of DL-2-amino-Delta2-thiazoline-4-carboxylic acid (DL-ATC) to L-cysteine increased significantly from 61.9 to 96.2%. The cross-linked antibody-protein A-MCMS showed its durability after repetitive use, maintaining a constant binding capacity for CD during five cycles. This study may lead to a convenient and cost-efficient method to produce L-cysteine by enzymatic conversions.
authors.affiliation: Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China.
authors.forename: Yangsheng
authors.initials: Y
authors.lastname: Yu
authors.forename: Gang
authors.initials: G
authors.lastname: Bai
authors.forename: Chunqin
authors.initials: C
authors.lastname: Liu
authors.forename: Yu
authors.initials: Y
authors.lastname: Cao
authors.forename: Peng
authors.initials: P
authors.lastname: Geng
authors.forename: Wenbo
authors.initials: W
authors.lastname: Yang
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D003542:Cystathionine gamma-Lyase / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D003545:Cysteine / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D008280:Magnetics; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D011549:Pseudomonas / Q000201:enzymology* / Q000235:genetics; D011773:Pyruvates / Q000378:metabolism; D011994:Recombinant Proteins / Q000276:immunology / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D011773:Pyruvates; D011994:Recombinant Proteins; D003542:Cystathionine gamma-Lyase; D003545:Cysteine