title: Mycobacterium avium-superoxide dismutase binds to epithelial cell aldolase, glyceraldehyde-3-phosphate dehydrogenase and cyclophilin A.
abstract: Mycobacterium avium complex (MAC) adheres, invades and multiplies inside epithelial cells. Earlier, we demonstrated two MAC protein adhesins, 25 and 31 kDa, binding with HEp-2 cells. The 25 kDa MAC adhesin was found to be superoxide dismutase (SOD). In this study, epithelial cell (HEp-2 and A549) ligands for MAC-SOD were identified by probing two-dimensional western blots of epithelial extracts with MAC proteins followed by monoclonal anti-MAC-SOD antibodies. Three epithelial cell proteins with molecular masses 43, 40 and 18 kDa, present in both membrane and cytosolic fractions, were found to bind with MAC-SOD. Based on the N-terminal amino acid sequences, the 43, 40 and 18 kDa epithelial proteins were identified as aldolase, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and cyclophilin A (CypA), respectively. Furthermore, MAC-SOD was found to bind to purified rabbit muscle aldolase, GAPDH and recombinant CypA in western blotting.
authors.affiliation: Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, IL 61107, USA. vmreddy@uic.edu
authors.forename: Venkata M
authors.initials: VM
authors.lastname: Reddy
authors.forename: Funmilayo G
authors.initials: FG
authors.lastname: Suleman
mesh_terms: D018829:Adhesins, Bacterial / Q000737:chemistry; D015153:Blotting, Western; D002460:Cell Line; D021984:Cyclophilin A / Q000737:chemistry / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D004847:Epithelial Cells / Q000201:enzymology* / Q000648:ultrastructure; D005634:Fructose-Bisphosphate Aldolase / Q000737:chemistry / Q000378:metabolism*; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008970:Molecular Weight; D015269:Mycobacterium avium Complex / Q000201:enzymology*; D011485:Protein Binding; D013482:Superoxide Dismutase / Q000737:chemistry / Q000378:metabolism*
chemical_list: D018829:Adhesins, Bacterial; D013482:Superoxide Dismutase; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D005634:Fructose-Bisphosphate Aldolase; D021984:Cyclophilin A