Binding assay and preliminary X-ray crystallographic analysis of ACTIBIND, a protein with anticarcinogenic and antiangiogenic activities.
ACTIBIND is a T2 RNase extracellular glycoprotein produced by the mould Aspergillus niger B1 (CMI CC 324626) that possesses anticarcinogenic and antiangiogenic activities. ACTIBIND was found to be an actin-binding protein that interacts with rabbit muscle actin in a 1:2 molar ratio (ACTIBIND:actin) with a binding constant of 16.17 x 10(4) M(-1). Autoclave-treated ACTIBIND (EI-ACTIBIND) lost its RNase activity, but its actin-binding ability was conserved. ACTIBIND crystals were grown using 20% PEG 3350, 0.2 M ammonium dihydrogen phosphate solution at room temperature (293 K). One to four single crystals appeared in each droplet within a few days and grew to approximate dimensions of 0.5 x 0.5 x 0.5 mm after about two weeks. Diffraction studies of these crystals at low temperature (100 K) indicated that they belong to the P3(1)21 space group, with unit-cell parameters a = 78, b = 78, c = 104 A.
de Leeuw
Marina
M
Department of Clinical Biochemistry, Faculty of Health Sciences, Ben-Gurion University, Beer-Sheva 84105, Israel.
Roiz
Levava
L
Smirnoff
Patricia
P
Schwartz
Betty
B
Shoseyov
Oded
O
Almog
Orna
O
D020533:Angiogenesis Inhibitors / Q000737:chemistry* / Q000378:metabolism*; D016588:Anticarcinogenic Agents / Q000737:chemistry* / Q000378:metabolism*; D018360:Crystallography, X-Ray; D004722:Endoribonucleases / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding / Q000502:physiology
D020533:Angiogenesis Inhibitors; D016588:Anticarcinogenic Agents; D004722:Endoribonucleases; C022543:ribonuclease T(2)