Identification, purification, and characterization of a secretory serine protease in an Indian strain of Leishmania donovani

摘要: An aprotinin sensitive serine protease was identified in the culture supernatant of Indian strain Leishmania donovani (MHOM/IN/1983/AG83). The subsequently purified and characterized. apparent molecular mass enzyme 115 kDa SDS-PAGE under non-reducing condition, while on reduction it showed a 56 protein band indicating that is dimeric protein. optimally active at pH temperature 7.5 28°C, respectively. Assays thermal stability indicated preserved 59% activity even after pretreatment 42°C for 1 h. not glycosylated its isoelectric pI 5.0. N-α-p-tosyl-l-arginine methylester (TAME) appeared to be relatively better substrate among commonly used synthetic substrates. inhibited by Ca2+ Mn2+, but activated Zn2+. could play important role(s) pathogenesis visceral leishmaniasis or kala-azar.