Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Characterization of an ecto-ATPase activity in Fonsecaea pedrosoi

Characterization of an ecto-ATPase activity in Fonsecaea pedrosoi In this work, we characterized an ecto-ATPase activity in intact mycelial forms of Fonsecaea pedrosoi , the primary causative agent of chromoblastomycosis. In the presence of 1 mM EDTA, fungal cells hydrolyzed adenosine-5′-triphosphate (ATP) at a rate of 84.6 ± 11.3 nmol Pi h −1 mg −1 mycelial dry weight. The ecto-ATPase activity was increased at about five times (498.3 ± 27.6 nmol Pi h −1 mg −1 ) in the presence of 5 mM MgCl 2 , with values of V max and apparent K m for Mg-ATP 2− corresponding to 541.9 ± 48.6 nmol Pi h −1 mg −1 cellular dry weight and 1.9 ± 0.2 mM, respectively. The Mg 2+ -stimulated ecto-ATPase activity was insensitive to inhibitors of intracellular ATPases such as vanadate (P-ATPases), bafilomycin A 1 (V-ATPases) , and oligomycin (F-ATPases). Inhibitors of acid phosphatases (molybdate, vanadate, and fluoride) or alkaline phosphatases (levamizole) had no effect on the ecto-ATPase activity. The surface of the Mg 2+ -stimulated ATPase in F. pedrosoi was confirmed by assays in which 4,4′-diisothiocyanostylbene-2,2′-disulfonic acid (DIDS), a membrane impermeant inhibitor, and suramin, an inhibitor of ecto-ATPase and antagonist of P 2 purinoreceptors. Based on the differential expression of ecto-ATPases in the different morphological stages of F. pedrosoi , the putative role of this enzyme in fungal biology is discussed. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Archives of Microbiology Springer Journals

Characterization of an ecto-ATPase activity in Fonsecaea pedrosoi

Download PDF
8 pages

Loading next page...
 
/lp/springer-journals/characterization-of-an-ecto-atpase-activity-in-fonsecaea-pedrosoi-drEXJUgVKc

References (74)

Publisher
Springer Journals
Copyright
Copyright © 2006 by Springer-Verlag
ISSN
0302-8933
eISSN
1432-072X
DOI
10.1007/s00203-006-0100-1
pmid
16528535
Publisher site
See Article on Publisher Site

Abstract

In this work, we characterized an ecto-ATPase activity in intact mycelial forms of Fonsecaea pedrosoi , the primary causative agent of chromoblastomycosis. In the presence of 1 mM EDTA, fungal cells hydrolyzed adenosine-5′-triphosphate (ATP) at a rate of 84.6 ± 11.3 nmol Pi h −1 mg −1 mycelial dry weight. The ecto-ATPase activity was increased at about five times (498.3 ± 27.6 nmol Pi h −1 mg −1 ) in the presence of 5 mM MgCl 2 , with values of V max and apparent K m for Mg-ATP 2− corresponding to 541.9 ± 48.6 nmol Pi h −1 mg −1 cellular dry weight and 1.9 ± 0.2 mM, respectively. The Mg 2+ -stimulated ecto-ATPase activity was insensitive to inhibitors of intracellular ATPases such as vanadate (P-ATPases), bafilomycin A 1 (V-ATPases) , and oligomycin (F-ATPases). Inhibitors of acid phosphatases (molybdate, vanadate, and fluoride) or alkaline phosphatases (levamizole) had no effect on the ecto-ATPase activity. The surface of the Mg 2+ -stimulated ATPase in F. pedrosoi was confirmed by assays in which 4,4′-diisothiocyanostylbene-2,2′-disulfonic acid (DIDS), a membrane impermeant inhibitor, and suramin, an inhibitor of ecto-ATPase and antagonist of P 2 purinoreceptors. Based on the differential expression of ecto-ATPases in the different morphological stages of F. pedrosoi , the putative role of this enzyme in fungal biology is discussed.

Journal

Archives of Microbiology – Springer Journals

Published: Jun 1, 2006

There are no references for this article.