%0 Journal Article %A AZOCAR, OMAR %A MUÑOZ, EMILIO %T Inhibition by Mercurial Reagents and Role of SH Groups of the Adenosine Triphosphatase from Escherichia coli 414 Membranes %D 1978 %J Microbiology, %V 108 %N 2 %P 239-246 %@ 1465-2080 %R https://doi.org/10.1099/00221287-108-2-239 %I Microbiology Society, %X Mercurials selectively inhibited Escherichia coli 414 ATPase (EC 3.6.1.3). Inhibition of the soluble ATPase (BF1) was greater than for the membrane-bound enzyme. The titration of 4 SH groups per mol BF1 with 0.05 mm-p-chloromercuri[14C]benzoate showed a good dose-response curve for the inhibition of basal ATPase but not for the trypsin-stimulated activity. Accessible SH groups did not seem to be related to the active site of the enzyme. Mercurials appeared to affect E. coli ATPase by inducing a molecular change in the holo-enzyme, followed by dissociation. One to two SH groups with different degrees of accessibility were located in the α and γ subunits of ATPase (BF1) but only one was located in the β subunit, irrespective of the concentration of p-chloromercuribenzoic acid, suggesting a structural role for SH groups in BF1. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-108-2-239