ISSN:
1750-3841
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Fraction I protein was extracted from fresh alfalfa (Medicago sativa) leaves and purified by ammonium sulfate fractionation, DEAE-cellulose and Sephadex G-200 chromatography. The isolate possessed a specific activity for ribulosebisphosphate carboxylase EC 4.1.1.39) of 1.01 units/mg protein. An approximate molecular weight of 573,000 was determined from values of So20,w (18.7) and Do20,w (2.97). The protein contained 26 disulfide and 37 sulfhydryl groups—only one of which was titratable in the undenatured protein complex. It migrated as a single boundry by Tiselius electrophoresis and as a dense zone in polyacrylamide gels (disc). In the presence of SDS, two principal subunits of ∼52,000 and ∼12,500 daltons were revealed. Based on the FAO/WHO (1973) provisional pattern for essential amino acids, the protein was slightly deficient in sulfur-containing residues.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2621.1981.tb04501.x
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