CRYSTALLIZATION AND PRELIMINARY-X-RAY STUDIES OF 2 SERINE PROTEINASE-INHIBITORS, BGIA AND BGIT, FROM THE SEEDS OF BITTER GOURD

Two serine proteinase inhibitors from seeds of the bitter gourd, BGIA (bitter gourd inhibitor against acidic amino acid-specific proteinase of Streptomyces griseus) and BGIT (bitter gourd trypsin inhibitor), we re crystallized for X-ray structure determination. Crystals of BGIA be long to the monoclinic space group C2 with cell dimensions of a = 54.0 Angstrom, b = 23.7 Angstrom, c = 47.9 Angstrom, and beta = 105.4 degr ees, and diffracted X-ray up to 1.5 Angstrom resolution. Crystals of B GIT belong to the triclinic space group P1 with cell dimensions of a = 22.8 Angstrom, b = 23.5 Angstrom, c = 28.4 Angstrom, alpha = 93.1 deg rees, beta = 99.6 degrees, and gamma = 101.0 degrees, giving X-ray dif fraction of over 1.2 Angstrom resolution. Intensity data of BGIA and B GIT crystals were collected using synchrotron radiation up to 1.7 and 1.4 Angstrom, respectively. (C) 1997 Academic Press.