[Identification of a neutral protease in the intestine of Boophilus microplus with electrophoresis in polyacrylamide gels copolymerized with gelatin]. / Identificación de una proteasa neutra en intestino de Boophilus microplus por electroforesis en geles de poliacrilamida copolimerizados con gelatina.

A neutral activity of Boophilus microplus in the intestine was identified by electrophoresis in polyacrilamide gel copolymerized with gelatin. The maximum of activity was attained at pH 6.0. The highest specific activity at that pH was obtained with casein substrate. The disappearance of this activity was observed in both substrates after the addition of phenylmethylsulphonyl fluoride in the reaction mixtures. It was very interesting to find out an endopeptidase activity with these characteristics in the intestine, in spite of the fact that the digestive activity in ticks is intracellular at very acid pH, which does not occur in other insects.

[Cathepsin L-like activity in hemolymph of females crammed with Boophilus microplus]. / Actividad semejante a catepsina L en la hemolinfa de hembras repletas de Boophilus microplus.

The cysteine-proteinase activity present in the hemolymph of females crammed with Boophilus microplus at the second oviposition was proved. The enzyme assay was performed using the synthetic N-carbobenzoxi-phenilalanyl-arginil-4-metoxibetan++ +-naphthylamide substrate, and hydrolysis in both raw ovarim extract and hemolymph were observed. The activity was 100% inhibited by trans-epoxisuscinyl-L-leucidamide (4-guadinine) butane, an specific inhibitor for cysteine-proteinase. Polyacrylamide and gelatin-gel electrophoresis showed the existence of only one active band in both samples tested with the same electrophoretic sliding (approximately 38 kDa).