摘要:
The present invention provides methods for the production of cysteine or derivates thereof by culturing a microorganism having reduced activity of endogenous phosphoserine phosphatase and the activity of PhnC, PhnD, and PhnE is reduced, and enhanced activity of phosphoglycerate dehydrogenase and/or phosphoserine aminotransferase. The O-phosphoserine produced by such an organism can then be reacted with a sulfide in the presence of a sulfydrylase or a microorganism expressing a sulfhydrylase to produce cysteine or a derivative thereof. Microorganisms having these reduced and enhanced properties noted above are also provided herein.
摘要:
Disclosed is an O-phosphoserine sulfhydrylase (OPSS) mutant which has a Mycobacterium smegmatis-derived amino acid sequence corresponding to that of SEQ ID NO: 1 which is devoid of three to seven C-terminal amino acid residues. Also, a nucleic acid molecule encoding the OPSS mutant, an expression vector carrying the nucleic acid molecule, and a transformant transformed with the expression vector are disclosed. In addition, a method is provided for producing cysteine in which O-phospho-L-serine (OPS) is reacted with a sulfide in the presence of the OPSS mutant. The OPSS mutant has improved enzymatic activity and can be applied to the environmentally friendly production of L-cysteine through a simple enzymatic conversion reaction.
摘要翻译:公开了一种O-磷酸丝氨酸二硫氢化酶(OPSS)突变体,其具有对应于SEQ ID NO:1的分枝杆菌衍生的氨基酸序列,其缺少3至7个C-末端氨基酸残基。 此外,公开了编码OPSS突变体的核酸分子,携带核酸分子的表达载体和用表达载体转化的转化体。 此外,提供了在OPSS突变体存在下,使O-磷酸-L-丝氨酸(OPS)与硫化物反应的半胱氨酸的制造方法。 OPSS突变体具有改善的酶活性,可以通过简单的酶转化反应应用于环保生产L-半胱氨酸。
摘要:
The present invention relates to a novel bacteriophage, more particularly, a bacteriophage that has a specific bactericidal activity against Salmonella enteritidis, Salmonella typhimurium, Salmonella gallinarum and Salmonella pullorum, a composition for the prevention or treatment of infectious diseases including salmonellosis and Salmonella food poisoning caused by Salmonella enteritidis or Salmonella typhimurium, Fowl typhoid caused by Salmonella gallinarum, and Pullorum disease caused by Salmonella pullorum, which comprises the bacteriophage as an active ingredient, and an animal feed, drinking water, cleaner, and sanitizer which comprise the bacteriophage as an active ingredient.
摘要:
An L-threonine-producing Escherichia coli in which a promoter of a phosphoenolpyruvate carboxylase (ppc) gene on the chromosome is substituted with a promoter of a cysteine synthase (cysK) gene and a method of producing L-threonine by using the same are disclosed. The recombinant Escherichia coli may produce L-threonine in a high yield, and thus may be widely used in medical, pharmaceutical, and feed industries, particularly for an animal feed.