caa a22 4500 445340398 CHVBK 20180317142810.0 cr unu---uuuuu 170323e20110901xx s 000 0 eng 10.1007/s00436-011-2284-9 doi (NATIONALLICENCE)springer-10.1007/s00436-011-2284-9 Identification and characterization of cysteine proteinases of Trypanosoma evansi [Elektronische Daten] [S. Yadav, R. Kumar, S. Kumar, U. Tatu, R. Singh, A. Gupta] Trypanosoma evansi is a causative agent of ‘surra', a common haemoprotozoan disease of livestock in India causing high morbidity and mortality in disease endemic areas. The proteinases released by live and dead trypanosomes entail immunosuppression in the infected host, which immensely contribute in disease pathogenesis. Cysteine proteinases are identified in the infectious cycle of trypanosomes such as cruzain from Trypanosoma cruzi, rhodesain or brucipain from Trypanosoma brucei rhodesiense and congopain from Trypanosoma congelense. These enzymes localised in lysosome-like organelles, flagellar pocket and on cell surface, which play a critical role in the life cycle of protozoan parasites, viz. in host invasion, nutrition and alteration of the host immune response. The paper describes the identification of cysteine proteinases of T. evansi lysate, activity profile at different pH optima and inhibition pattern using a specific inhibitor, besides the polypeptide profile of an antigen. Eight proteinases of T. evansi were identified in the molecular weight (MW) ranges of 28-170kDa using gelatin substrate-polyacrylamide gel electrophoresis (GS-PAGE), and of these proteinases, six were cysteine proteinases, as they were inhibited by L-3-carboxy-2,3-transepoxypropionyl-lecuylamido (4-guanidino)-butane (E-64), a specific inhibitor. These proteolytic enzymes were most reactive in acidic pH between 3.0 and 5.5 in the presence of dithiothreitol and completely inactive at alkaline pH10.0. Similarly, the GS-PAGE profile of the serum samples of rats infected with T. evansi revealed strong proteolytic activity only at the 28-kDa zone at pH5.5, while no proteolytic activity was observed in serum samples of uninfected rats. Further, the other zones of clearance, which were evident in T. evansi antigen zymogram, could not be observed in the serum samples of rats infected with T. evansi. The polypeptide pattern of the whole cell lysate antigen revealed 12-15 polypeptide bands ranging from 28 to 81kDa along with five predominant polypeptides bands (MW of 81, 66, 62, 55 and 45kDa), which were immunoreactive with hyperimmune serum (HIS) and serum of experimentally infected rabbits with T. evansi infection. The immunoblot recognised antibodies in experimentally infected rabbits and against HIS as well, corresponding to the zone of clearances at lower MW ranges (28-41kDa), which may be attributed to the potential of these proteinases in the diagnosis of T. evansi infection. Since these thiol-dependent enzymes are most active in acidic pH and considering their inhibition characteristics, these data suggest that they resemble to the mammalian lysosomal cathepsin B and L. Springer-Verlag, 2011 Yadav S. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut Kumar R. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut Kumar S. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut Tatu U. Department of Biochemistry, Indian Institute of Science, Bangalore, India aut Singh R. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut Gupta A. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut Parasitology Research Springer-Verlag 109/3(2011-09-01), 559-565 0932-0113 109:3<559 2011 109 436 https://doi.org/10.1007/s00436-011-2284-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00436-011-2284-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yadav S. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut NATIONALLICENCE 700 1- Kumar R. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut NATIONALLICENCE 700 1- Kumar S. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut NATIONALLICENCE 700 1- Tatu U. Department of Biochemistry, Indian Institute of Science, Bangalore, India aut NATIONALLICENCE 700 1- Singh R. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut NATIONALLICENCE 700 1- Gupta A. National Research Centre on Equines, Sirsa Road, 125001, Hisar, Haryana, India aut NATIONALLICENCE 773 0- Parasitology Research Springer-Verlag 109/3(2011-09-01), 559-565 0932-0113 109:3<559 2011 109 436 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer