Brown, Gavin M. and Millar, Alan R. and Masterson, Claire and Brimacombe, John S. and Nikolaev, Andrei V. and Ferguson, Michael A. (1996) Synthetic phosphooligosaccharide fragments of lipophosphoglycan as acceptors for Leishmania-major alpha-Dmannosylphosphate transferase. European Journal of Biochemistry, 242 (2). pp. 410-416. ISSN 0014-2956Full text not available from this repository.
Protozoan parasites of the genus Leishmania synthesise lipophosphoglycans, phosphoglycans and proteophosphoglycans that contain phosphosaccharide-repeat units of [-6Galβ1-4Manα1-P-]. In this study, a GDP-Man-dependent α-mannosylphosphate-transferase activity was detected in washed Leishmania major membranes using synthetic phospho-oligosaccharide fragments of lipophosphoglycan as acceptor substrates. The divalent-cation-dependent α-mannosylphosphate-transferase activity had an apparent Km for GDP-Man of about 15–20 μM and a pH optimum of 7.0. The activity showed a requirement for a non-reducing terminal βGal residue and for one or more phosphodiester units preceding the acceptor site. Based on these results, the activity may be defined as a GDP-Man:Galβ1-4Manα1-P-R α-mannosylphosphate-transferase. This acceptor specificity is consistent with a role for the α-mannosylphosphate transferase in the elongation of phosphosaccharide-repeat domains of Leishmania glycoconjugates rather than in the priming of these domains. An identical or similar activity must exist in the amastigote forms of the Leishmania that produce and secrete proteophosphoglycan material and the activity therefore represents a feasible target for the development of chemotherapeutics.
|Journal or Publication Title:||European Journal of Biochemistry|
|Uncontrolled Keywords:||lipophosphoglycan • proteophosphoglycan • Leishmania • phospho-oligosaccharide biosynthesis|
|Subjects:||G Geography. Anthropology. Recreation > GE Environmental Sciences|
|Departments:||Faculty of Health and Medicine > Biomedical & Life Sciences|
|Deposited On:||17 Feb 2009 09:36|
|Last Modified:||26 Jul 2012 15:54|
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