Regulation of colominic acid biosynthesis by temperature: role of cytidine 5'-monophosphate N-acetylneuraminic acid synthetase.
Synthesis of colominic acid in Escherichia coli K-235 is strictly regulated by temperature. Evidence for the role of cytidine 5'-monophospho-N-acetylneuraminic acid (CMP-Neu5Ac) synthetase in this regulation was obtained by measuring its level in E. coli grown at 20 and 37 degrees C. No activity was found in E. coli grown at 20 degrees C. CMP-Neu5Ac started to be quickly synthesized when bacteria grown at 20 degrees C were transferred to 37 degrees C and was halted when cells grown at 37 degrees C were transferred to 20 degrees C. These findings suggest that temperature regulates the synthesis of this enzyme and therefore the concentration of CMP-Neu5Ac necessary for the biosynthesis of colominic acid.
González-Clemente
C
C
Department of Biochemistry and Molecular Biology, University of León, Campus de Vegazana, Spain.
Luengo
J M
JM
Rodríguez-Aparicio
L B
LB
Reglero
A
A
D004926:Escherichia coli / Q000378:metabolism; D000216:N-Acylneuraminate Cytidylyltransferase / Q000502:physiology*; D009713:Nucleotidyltransferases / Q000502:physiology*; D011134:Polysaccharides / Q000096:biosynthesis*; D013696:Temperature
D011134:Polysaccharides; C014420:colominic acid; D009713:Nucleotidyltransferases; D000216:N-Acylneuraminate Cytidylyltransferase