Abstract
In an attempt to determine structural similarity of Aeromonas aminopeptidase (AAP) and an endopeptidase of A. proteolytica with other proteases, the antisera of these two Aeromonas enzymes were allowed to react by immunodiffusion with representatives of the various classes of proteolytic enzymes. A definitive reaction of identity resulted with papain, a sulfhydryl plant enzyme, and the antisera of both Aeromonas enzymes after an incubation period of 7 days; no other protease showed immunochemical similarities with either of the Aeromonas enzymes by this method. The activity of AAP was inhibited to an extent greater than 50% when the enzyme was preincubated with 200μg of its homologous antiserum, then assayed with L-leucyl-β-napthylamide as the substrate. Aeromonas endopeptidase activity toward casein substrate was reduced to only 20% of its original value by preincubation with 1.50 mg of anti-AAP. In contrast, B. licheniformis aminopeptidase activity was stimulated to an extent of more than 60% when it was preincubated with 450 μg of anti-AAP, and the activities of the aminopeptidase or pronase and of leucine aminopeptidase were not affected by anti-AAP. The activities of subtilisin and subtilopeptidase A toward casein substrate were stimulated by 50% and 55%, respectively, by treatment of these B. subtilis enzymes with 2.5 mg of anti-AAP. ...
Miller, Joyce Mary (1972). Immunochemical and active site studies on an aminopeptidase from Aeromonas proteolytica. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -185434.