Premium
Semen sialic acid surge and modulation of α‐ L ‐fucosidase activity: possible link to loss in reproductive capacity during trypanosomiasis
Author(s) -
Oluyinka Okubanjo O.,
Mairo Inuwa H.,
Ajanusi Joseph A.,
David Ogwu,
Sekoni Victor,
Nok Andrew J.
Publication year - 2008
Publication title -
cell biochemistry and function
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.933
H-Index - 61
eISSN - 1099-0844
pISSN - 0263-6484
DOI - 10.1002/cbf.1415
Subject(s) - semen , sialic acid , biology , semen quality , enzyme , andrology , chemistry , biochemistry , medicine , anatomy
The profiles of semen sialic acid and the enzyme α‐L‐fucosiadase were studied in rams undergoing chronic infection by Trypanosoma congolense . Our data showed a significant surge in the level of sialic acid with parasitaemia. The pattern followed a polynomial function we had reported for erythrocyte sialic acid in mice undergoing acute infection by T. congolense .1 The activity of the enzyme α‐fucosidase decreased progressively with approximately 60% decrease at the end of the 14 weeks of infection. Representative semen samples from the control and infected rams were subjected to kinetic characterization. While the uninfected semen sample showed two active pH peaks at 4.5–5.5 and at 6.8–7.2, respectively, there was an apparent shift to only a single pH optimum at 4.5–5.5 for the pathological semen. The fucosidases from both sources were optimally active at 35°C albeit with contrasting activation energies ( E a ) with values 20.58 and 35 kJ/mol for the control and infected semen, respectively. Kinetic studies using methylumbelliferyl‐β‐fucoside (4MU‐Fuc) as substrate gave K M and V max values of 3.25 µM and 14.6 µmol. min −1 mg −1 , respectively for the control semen. The values for the infected semen were 18.25 µM and 10.5 µmol. min −1 mg −1 , respectively. The significance of these results is discussed as they relate to loss in reproductive capacity in trypanosomoses. Copyright © 2007 John Wiley & Sons, Ltd.