Open AccessSome pecularities of functioning of H + ‐ATPase from the membranes of the anaerobic bacterium Lactobacillus casei
Author(s) -
MILEYKOVSKAYA Evgenia I.,
ABULADZE An.,
KORMER Svetlana S.,
OSTROVSKY Dmitrii N.
Publication year - 1987
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1987.tb13346.x
Subject(s) - lactobacillus casei , atpase , enzyme , biochemistry , anaerobic exercise , atp hydrolysis , micrococcus luteus , bacteria , biology , hydrolysis , chemistry , escherichia coli , physiology , genetics , fermentation , gene
Radiation inactivation analysis gave the target sizes of 176 + 5 kDa and 275 + 33 kDa for ATPase from anaerobic Lactobacillus casei and aerobic Micrococcus luteus bacteria respectively. The values are close to the known molecular masses of the enzymes. Thus, to function the L. casei ATPase, like the F 1 ‐ATPases, requires a complete structure composed of all the enzyme subunits. L. casei ATPase is inhibited by 4‐chloro‐7‐nitrobenzo‐2‐oxa‐1,3‐diazole owing to modification of an amino acid residue(s) with p K > 8.5. L. casei ATPase consists of six identical subunits and differs from α 3 β 3 γδɛ‐type F 1 ‐ATPases in a number of catalytic properties. Namely, ATP hydrolysis under the ‘unisite’ conditions proceeds at a relatively high rate suggesting the absence of cooperative interactions between the catalytic sites. Contrary to mitochondrial F 1 ‐ATPase. L. casei ATPase does not form an inactive complex with ADP. These findings imply essential differences in the operating mechanism for L. casei ATPase and F 1 ATPase.