title: Homology modeling and identification of amino acids involved in the catalytic process of Mycobacterium tuberculosis serine acetyltransferase.
abstract: Serine acetyltransferase (CysE) belongs to the hexapeptide acetyltransferase family and is involved in the biosynthesis of L‑cysteine in microorganisms. Mycobacterium tuberculosis CysE is regarded as a potential target for anti‑tuberculosis (TB) drugs; however, the structure and active sites of M. tuberculosis CysE remain unknown. The present study aimed to predict the secondary structure and to construct a 3D model for M. tuberculosis CysE using bioinformatics analysis. To determine the essential amino acids that are associated with CysE enzymatic activity, amino acid sequences from several microorganisms were compared, and a consensus sequence was identified. Subsequently, site‑directed mutagenesis was used to generate mutant M. tuberculosis CysE proteins. Enzyme assays demonstrated that D67A, H82A and H117A mutants abolished ~75% activity of M. tuberculosis CysE. Prediction of the protein structure and identification of the active amino acids for M. tuberculosis CysE is essential for designing inhibitors, which may aid the discovery of effective anti‑TB drugs.
authors.affiliation: Centralab, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China.
authors.forename: Juanjuan
authors.initials: J
authors.lastname: Qiu
authors.affiliation: Department of Biotechnology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Shizhu
authors.initials: S
authors.lastname: Zang
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Yufang
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Department of Biotechnology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Lawrence
authors.initials: L
authors.lastname: Owusu
authors.affiliation: Clinical Laboratory, Dalian Blood Centre, Dalian, Liaoning 116001, P.R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Biotechnology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Jiang
authors.affiliation: Department of Biotechnology, Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xin
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry*; D002384:Catalysis; D020134:Catalytic Domain; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000201:enzymology / Q000235:genetics; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D051050:Serine O-Acetyltransferase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D000596:Amino Acids; D051050:Serine O-Acetyltransferase