Characterization of the major plasma apoliproteins of the high density lipoprotein in the carp (Cyprinus carpio)

1. 1. Carp plasma DHL was isolated by a single chromatographic procedure using Affi-Gel Blue. Neither LDL nor VLDL were detected. 2. 2. Thus, HDL which comprises almost 40% of the total carp plasma proteins, also constitutes the major lipoprotein fraction in this fish, yielding two apolipoproteins: apo A-I and apo A-II with molecular weight of 29,500 and 12,000, respectively. These are present in a one to one molar ratio. 3. 3. Carp apo A-I and apo A-II lack cysteine and tryptophan. Although some similarities in the amino acid composition exist with respect to the same apoproteins from other organisms, antisera raised against carp apo-I cross-reacted only, and very slightly, with its rainbow trout counterpart. 4. 4. No reaction was detected with lamprey and the nothotenidae robalo fish. 5. 5. Four plasmatic apo A-I isoforms were identified. No differences were observed in carps acclimatized to winter and summer.