title: Three-step biocatalytic reaction using whole cells for efficient  production of tyramine from keratin acid hydrolysis wastewater.
abstract: Tyramine has been paid more attention in recent years as a significant metabolite of tyrosine and catecholamine drug and an intermediate of medicinal material and some drugs. In this study, an effective, green, and three-step biocatalytic synthesis method for production of tyramine starting from serine in keratin acid hydrolysis wastewater was developed and investigated. Serine deaminase from Escherichia coli was first combined with tyrosine phenol-lyase from Citrobacter koseri, to convert L-serine to L-tyrosine. L-Tyrosine can then be decarboxylated to tyramine by tyrosinede carboxylase from Lactobacillus brevis. All these enzymes originated from recombinant whole cells. Serine deaminaseand tyrosine phenol-lyase could efficiently convert L-serine in wastewater to L-tyrosine at pH 8.0, 37 °C, and Triton X-100 of 0.04% when tyrosine phenol-lyase and its corresponding substrates were sequentially added. Tyrosine conversion rate reached 98 % by L-tyrosine decarboxylase. In scale-up study, the conversion yield of L-serine in wastewater to tyrosine was up to 89 %. L-Tyrosine was decarboxylated to tyramine with a high yield 94 %. Tyramine hydrochloride was obtained with a total yield 84 %. This study has provided an efficient way of recycling keratin acid hydrolysis wastewater to produce tyramine.
authors.affiliation: School of Pharmacy, Nanjing Medical University, Nanjing, 211166, China.|State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, China.
authors.forename: Hongjuan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, China.
authors.forename: Siping
authors.initials: S
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, China. junzhongliu2414@163.com.
authors.forename: Junzhong
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, China. jiaoqc@163.com.
authors.forename: Qingcai
authors.initials: Q
authors.lastname: Jiao
mesh_terms: D000143:Acids; D041041:Citrobacter koseri / Q000201:enzymology / Q000235:genetics; D004798:Enzymes / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007633:Keratins / Q000378:metabolism; D052196:Levilactobacillus brevis / Q000201:enzymology / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012694:Serine / Q000378:metabolism*; D013696:Temperature; D014439:Tyramine / Q000378:metabolism*; D062065:Wastewater
chemical_list: D000143:Acids; D004798:Enzymes; D007633:Keratins; D011994:Recombinant Proteins; D012694:Serine; D014439:Tyramine; D062065:Wastewater