K. Zeth et al., CRYSTALLIZATION AND PRELIMINARY-X-RAY CRYSTALLOGRAPHIC STUDIES OF THENATIVE AND CHEMICALLY-MODIFIED ANION-SELECTIVE PORIN FROM COMAMONAS-ACIDOVORANS, Acta crystallographica. Section D, Biological crystallography, 54, 1998, pp. 650-653
Citations number
21
Categorie Soggetti
Crystallography,"Biochemical Research Methods",Biophysics,Biology
Omp32, the strongly anion-selective porin from Comamonas acidovorans,
has been crystallized. Two crystal forms were observed, both of which
belong to space group R3, but exhibit different cell dimensions a = b
= 106.7, c = 140.6 Angstrom (crystal form I) and a = b = 87.1, c = 135
.3 Angstrom (crystal form II) with one trimer per asymmetric unit. The
crystals diffract to 2.2 and 2.3 Angstrom resolution, respectively. O
mp32 was chemically modified by introducing negative charges through s
uccinylation. The number and positions of the individual modifications
were determined using mass spectrometry and X-ray crystallography. Ch
emically modified porins yielded crystals of a third form, also of spa
ce group R3 but with cell constants of a = b = 109.3 and c = 263.2 Ang
strom (crystal form III), showing a virtually doubled c axis. Crystals
of form III diffract to 3.5 Angstrom resolution.