News Column

New Essential Amino Acids Study Findings Have Been Reported by Researchers at Rhodes University

January 28, 2014



By a News Reporter-Staff News Editor at Life Science Weekly -- A new study on Essential Amino Acids is now available. According to news originating from Grahamstown, South Africa, by NewsRx correspondents, research stated, "Arginine kinase is not only absent from mammalian hosts but is critical to the survival of trypanosomes under stressful conditions and consequently its inhibition may lead to an effective treatment for trypanosomiasis. The His-tagged enzyme was cloned from Trypanosoma brucei genomic DNA, expressed in Escherichia coli BL21 DE3 cells and purified on a Ni-affinity column and by FPLC on a Superdex 200 HR."

Our news journalists obtained a quote from the research from Rhodes University, "The enzyme had a specific activity of 2.92 ?mol min(-1) mg protein(-1), molecular mass of 40 kDa, temperature and pH optima of 30 C and 7.8, and Km and Vmax as 2.94 mM and 0.161 ?mol ml(-1) min(-1) (arginine substrate). The interaction of the enzyme with silver and gold nanoparticles showed a non-competitive inhibition with, respectively, 75% and 62% decrease in activity; Ki values ranged from 1.5 nM (Ag) to 3.1 nM (Au). A mechanism for this inhibition was by interaction with Cys(271) positioned 3.3 A from the reactive NH(1) of substrate arginine."

According to the news editors, the research concluded: "This cysteine controls electrophilic and nucleophilic character of the guanidinium group that is crucial for enzymatic phosphoryl transfer between ADP and ATP."

For more information on this research see: Interaction of nanoparticles with arginine kinase from Trypanosoma brucei: kinetic and mechanistic evaluation. International Journal of Biological Macromolecules, 2013;62():450-6. (Elsevier - www.elsevier.com; International Journal of Biological Macromolecules - www.elsevier.com/wps/product/cws_home/525446)

The news correspondents report that additional information may be obtained from O.S. Adeyemi, Dept. of Biochemistry, Microbiology & Biotechnology Rhodes University, Grahamstown, South Africa (see also Essential Amino Acids).

Keywords for this news article include: Grahamstown, South Africa, Nanoparticle, Nanotechnology, Arginine Kinase, Basic Amino Acids, Diamino Amino Acids, Emerging Technologies, Enzymes and Coenzymes, Essential Amino Acids, Phosphotransferases (Nitrogenous Group Acceptor).

Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC


For more stories covering the world of technology, please see HispanicBusiness' Tech Channel



Source: Life Science Weekly


Story Tools