TY - JOUR
T1 - Hemoglobin induces binding of several extracellular matrix proteins to Candida albicans
T2 - Identification of a common receptor for fibronectin, fibrinogen, and laminin
AU - Yan, Sizhuang
AU - Rodrigues, Rui G.
AU - Cahn-Hidalgo, Diego
AU - Walsh, Thomas J.
AU - Roberts, David D.
PY - 1998/3/6
Y1 - 1998/3/6
N2 - Host infection by the pathogenic fungus Candida albicans is initiated by adhesion and mediated by binding to several host extracellular matrix proteins. Previously, we demonstrated that hemoglobin supplemented into a chemically defined medium significantly and specifically induced fibronectin binding to C. albicans. We now report that hemoglobin also induces binding of laminin, fibrinogen, and type IV collagen but not of thrombospondin-1 or type I collagen. The binding of each protein was inhibited by the respective unlabeled ligand in a concentration-dependent manner. Fibrinogen inhibited the binding of radiolabeled fibronectin, laminin, and fibrinogen with similar IC50 values, suggesting that a single promiscuous receptor recognizes these three proteins. Competitive binding studies indicated that a second class of receptor binds specifically to laminin. Growth of C. albicans in the presence of hemoglobin also increased cell adhesion to immobilized fibronectin, laminin, fibrinogen, and type IV collagen but not to thrombospondin-1 or type I collagen. Exposure to hemoglobin induced increased or de nero expression of several surface proteins on C. albicans. One of these proteins with a molecular weight of 55,000 recognized fibronectin, based on ligand protection and affinity chromatography on immobilized fibronectin. Thus, hemoglobin induces both promiscuous and specific receptors for extracellular matrix proteins and, therefore, may regulate matrix adhesion during dissemination of C. albicans infections.
AB - Host infection by the pathogenic fungus Candida albicans is initiated by adhesion and mediated by binding to several host extracellular matrix proteins. Previously, we demonstrated that hemoglobin supplemented into a chemically defined medium significantly and specifically induced fibronectin binding to C. albicans. We now report that hemoglobin also induces binding of laminin, fibrinogen, and type IV collagen but not of thrombospondin-1 or type I collagen. The binding of each protein was inhibited by the respective unlabeled ligand in a concentration-dependent manner. Fibrinogen inhibited the binding of radiolabeled fibronectin, laminin, and fibrinogen with similar IC50 values, suggesting that a single promiscuous receptor recognizes these three proteins. Competitive binding studies indicated that a second class of receptor binds specifically to laminin. Growth of C. albicans in the presence of hemoglobin also increased cell adhesion to immobilized fibronectin, laminin, fibrinogen, and type IV collagen but not to thrombospondin-1 or type I collagen. Exposure to hemoglobin induced increased or de nero expression of several surface proteins on C. albicans. One of these proteins with a molecular weight of 55,000 recognized fibronectin, based on ligand protection and affinity chromatography on immobilized fibronectin. Thus, hemoglobin induces both promiscuous and specific receptors for extracellular matrix proteins and, therefore, may regulate matrix adhesion during dissemination of C. albicans infections.
UR - http://www.scopus.com/inward/record.url?scp=0032489514&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032489514&partnerID=8YFLogxK
U2 - 10.1074/jbc.273.10.5638
DO - 10.1074/jbc.273.10.5638
M3 - Article
C2 - 9488693
AN - SCOPUS:0032489514
SN - 0021-9258
VL - 273
SP - 5638
EP - 5644
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 10
ER -