The late Professor Stang Mongkolsuk: a role model as an excellent researcher, teacher, and visionary administrator.

To most Thais who knew him, Prof. Stang Mongkolsuk was a visionary administrator. To practically all of his students who were fortunate enough to have attended his lectures, he was an excellent teacher and a life-long mentor. But to the past and present members of the Faculty of Science, Mahidol University, Thailand, it was Prof. Stang’s commitment to research that fostered the research culture and research tradition that became the hallmark of the Faculty for succeeding generations.

Isolation, purification, and characterization of L-glutamate oxidase from Streptomyces sp. 18G

An extracellular L-glutamate oxidase (GLOD) was purified from soil-isolated Streptomyces sp 18G. The enzyme had a molecular weight of approximately 120,000 and consisted of two identical subunits, each with a molecular weight of 61,000. The isoelectric point was pH 8.5 and the enzyme had an optimal pH between 7.0-7.4. GLOD showed the maximum activity at 37ºC. The GLOD activity was stable at pH ranging from 6.5 to 7.0 for 1 hr. Among 21 amino acids tested for substrate specificity, L-glutamate was almost exclusively oxidized. D-glutamate and L-aspartate were oxidized but only to extents of 0.79 percent and 0.53 percent, respectively.