Abstract
Aspartokinase fromMicrococcus glutamicus AEC RN-13-6/1 [a homoserine requiring, S-(2-aminoethyl)-L-cysteine resistant, lysine producing strain] was purified 71 fold. The partially purified enzyme was inhibited by L-lysine. L-threonine, L-methionine, L-isoleucine, L-valine and L-phenylalanine activated the enzyme and reversed the inhibition by L-lysine. Aspartokinase activity was not derepressed by growth-limiting concentrations of L-threonine and/or L-methionine. It was not repressed by an excess of L-lysine (20 mM) and/or L-isoleucine (15.3 mM). The degree of activation or inhibition by amino acids was dependant on the composition of the growth medium. This observation is in contrast with the enzyme from the original (non-lysine-producing) strain which was inhibited by lysine or threonine and in a concerted manner by threonine plus lysine.
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Abbreviations
- AEC or aminoethyl cysteine:
-
S-(2-aminoethyl)-L-cysteine
- Lys:
-
L-lysine
- L-Asp:
-
L-aspartate
- Thr:
-
L-threonine
- IIe:
-
L-isoleucine
References
Black, S. (1962)Methods Enzytmol.,5, 821.
Black, S. and Wright, N. G. (1955)J. Biol. Chem.,213, 39.
Drazic, M. and Vitale, L. (1974)Period. Biol.,76, 85.
Halsall, D. M. (1975)Biochem. Genet.,13, 109.
Hermann, M., Thevenet, N. J., Condort-Maratier, M. M. and Vandecasteele, J. P. (1972)Eur. J Biochem.,30, 100.
Jegede, V., Spencer, F. and Brenchley, J. E. (1976)Genetics,83, 619.
Kase, H. and Nakayama, K. (1974)Agric. Biol. Chem.,38, 993.
Lakshman, M. (1980)Studies on the biosynthesis of the aspartate family of amino acids in bacteria, Ph.D. thesis, University of Mysore, Mysore.
Lowry, O. H., Rosebrough, N. J., Farr, A. L. and Randall, R. J. (1951)J. Biol. Chem.,193, 265.
Nakayama, K., Tanaka, H., Hagino, H. and Kinoshita, S. (1966)Agric. Biol. Chem.,30, 611.
Sano, K. and Shiio, I. (1967)J. Gen. Appl. Microbiol.,13, 349.
Shiio, I. and Miyajima, R. (1969)J. Biochem.,65, 849.
Shiio, I., Miyajima, R. and Sano, K. (1970)J.Biochem.,68, 701.
Tosaka, O., Takinami, K. and Hirose, Y. (1978)Agric. Biol. Chem.,42, 745.
White, P. J. (1971)Methods Enzymol,B17, 140.
Yugari, Y. and Gilvarg, C. (1965)J. Biol. Chem.,240, 4710.
Zaitseva, Z. M. and Chernysheva, I. P. (1975)Biochemistry (USSR),40, 58.
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Lakshman, M., Shenoy, B.C. & Rao, M.R.R. Aspartokinase of a lysine producing mutant ofMicrococcus glutamicus . J Biosci 3, 57–67 (1981). https://doi.org/10.1007/BF02703348
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DOI: https://doi.org/10.1007/BF02703348