Studies on the water soluble lens proteins of the lizard, Calotes versicolor. I. Fractionation and molecular weight determination

Abstract

The water soluble lens proteins of the lizard, Calotes versicolor are characterized by Sephadex G-200 gel filtration, isoelectric precipitation and paper electrophoresis. Gel filtration resolves the total soluble lens proteins into four fractions, F 1 to F 4. The molecular weights of these are around 410 000, 160 000, 70 000 and 6500; and they constitute 0·16, 0·08, 0·57 and 0·18 of the total soluble lens proteins respectively. From the molecular weights, F 1 and F 3 appear to be α- and β-crystallins respectively. F 2, a minor fraction, may be either δ-crystallin or a high molecular weight β-crystallin. F 4, the most retained fraction on Sephadex gel column is interesting, since it is the first report of such a low molecular weight crystallin from vertebrate lens. Results of isoelectric precipitation of proteins at pH 5·0 and subsequent gel filtration confirm that F 1 of the gel filtration is α-crystallin. Paper electrophoresis also reveals three bands, possibly corresponding to F 1, F 3 and F 4 gel filtration fractions.