We studied the kinetic characterizations of the Trifolium pratense seedlings copper-containing amine oxidase(TPAO) by using various amine-containing substrates.The catalyzing rate for all of amine-containing substrate...We studied the kinetic characterizations of the Trifolium pratense seedlings copper-containing amine oxidase(TPAO) by using various amine-containing substrates.The catalyzing rate for all of amine-containing substrates can be ordered as diamines > polyamines > aromatic monoamines,and it shows an apparent trend in each category of substrates such as the longer the carbon chain,the lower the V_(max) is,so does the V_(max)/K_m values but is opposite for the K_m value of TPAO.The distinct differences between the kinetic parameters for different amine-containing substrates indicated that the rate-determining step of the catalytic reaction strongly depends on the substrate's chemical structure.It is concluded that both pH and ionic strength can affect the catalytic activity of TPAO via influencing the coulomb interaction-mediated enzyme-substrate docking processes,which can be attributed to the potential of charged groups from both substrates and the activity sites of TPAO by the regulation of ionic strength.展开更多
基金supported by the Department of Education of Inner Mongolia and Inner Mongolia Natural Science Foundation of China for Basic Research(No.NJZY13054)the National Natural Science Foundation of China(Nos.31360214,21171086 and 81160213)+3 种基金the Inner Mongolia Autonomous Region Science and Technology Department(No.211-202077)the Inner Mongolia Grassland Talent(No.108-108038)the Natural Science Foundation of Inner Mongolia Autonomous Region of China(Nos.2013MS1121 and 2015MS0806)the Inner Mongolia Agricultural University(Nos.109-108040,211-109003 and 211-206038)
文摘We studied the kinetic characterizations of the Trifolium pratense seedlings copper-containing amine oxidase(TPAO) by using various amine-containing substrates.The catalyzing rate for all of amine-containing substrates can be ordered as diamines > polyamines > aromatic monoamines,and it shows an apparent trend in each category of substrates such as the longer the carbon chain,the lower the V_(max) is,so does the V_(max)/K_m values but is opposite for the K_m value of TPAO.The distinct differences between the kinetic parameters for different amine-containing substrates indicated that the rate-determining step of the catalytic reaction strongly depends on the substrate's chemical structure.It is concluded that both pH and ionic strength can affect the catalytic activity of TPAO via influencing the coulomb interaction-mediated enzyme-substrate docking processes,which can be attributed to the potential of charged groups from both substrates and the activity sites of TPAO by the regulation of ionic strength.