UNS:New protein function: developing a family of amine dehydrogenases

用于药物生产的生物相容分子通常需要独特的分子结构，而这种分子结构只能通过使用称为酶的生物催化剂容易地以纯形式制造。这项研究的目标是设计一类被称为胺脱氢酶(AmDHs)的酶，以便它们能够将普通的酮转化为一种特定的化合物，即手性胺。由此得到的结构独特的含氮手性化合物可能通过比传统(非生物)化学合成更简单、成本更低的路线被用作广泛的新药物的构建块。佐治亚理工学院和阿姆斯特朗州立大学(以本科生为主)的这项合作将为阿姆斯特朗州立大学的学生提供研究机会，同时也为佐治亚理工学院的研究生提供教和学的机会。PI最近通过蛋白质工程从相应的氨基酸脱氢酶(AADH)中设计了三个(R)特定的胺脱氢酶(AmDHs)。这些AmDHs催化前手性酮的还原胺化成手性胺。本提案扩展了这一研究路线，以创造相同酶的变体，以实现(S)-胺的合成。为了支持这一努力，该研究将通过加宽酮和辅因子结合口袋以及通过加强氨结合来增加底物特异性。用于这些修饰的主要工具是对关键残基进行定点或定点饱和突变，后者通过中子散射确定的晶体结构进行鉴定。这项研究可能会产生具有商业意义的结果，特别是对于手性胺是重要中间体的制药行业。酮的还原胺化合成手性胺是医药中间体生产中的一项重要变革。因此，能够选择性合成手性胺的工业上适用的酶促方法可能是非常有用的。两所大学计划在本科生和研究生水平上进行学生交流。这些不仅将有助于研究，而且还将在这两个机构提供教育和推广机会。

Bio-compatible molecules used in the production of pharmaceuticals often require unique molecular structures that can only be readily made in pure form by the use of biological catalysts known as enzymes. The goal of the present study is to engineer a class of enzymes known as amine dehydrogenases (AmDHs) so that they can convert a common ketone into a specific compound known as a chiral amine. The resulting uniquely-structured nitrogen-containing chiral compound can potentially be used as a building block for a wide range of new pharmaceutical products through simpler and less costly routes than by conventional (non-biological) chemical synthesis. This collaboration between Georgia Tech and Armstrong State University (a predominantly undergraduate institution) will provide research opportunities for Armstrong State students while also providing teaching and learning opportunities for graduate students from Georgia Tech.The PI recently designed three (R)-specific amine dehydrogenases (AmDHs) from the corresponding amino acid dehydrogenases (AADHs) via protein engineering. These AmDHs catalyze the reductive amination of prochiral ketones into chiral amines. The present proposal extends this line of research to create variations of the same enzymes to achieve (S)-amines synthesis. In support of this effort, the research will increase substrate specificity by broadening the ketone and co-factor binding pockets, and by tightening ammonia binding. The main tool used for these modifications is site-directed or site-saturated mutagenesis on key residues, the latter being identified by crystal structures determined by neutron scattering. The study is likely to yield results that will be of commercial significance, especially to the pharmaceutical industry for which the chiral amines are important intermediates. The reductive amination of ketones to produce chiral amines is an important transformation in the production of pharmaceutical intermediates. Therefore, industrially applicable enzymatic methods that enable the selective synthesis of chiral amines could be very useful. Exchanges in students at both the undergraduate and graduate levels between the two universities are planned. These will not only aid the research, but also provide educational and outreach opportunities at both institutions.