Clupein

C22H34O2. A straight-chain fatty acid with 5 double bonds. A major component of fish oils and the oils of marine animals, clupeine Protamine class protein found in the sperm and testicles of the herring. On hydrolysis it gives about 90% of argenine. 

I. Protamines, e.g., salmine, sturine, clupeine, scombrine, cyclop-terine, cyprinine,... 

Salmine. (Kossel Abderhalden Kossel and Dakin.) Sturine. (Kossel and Kutscber. Clupeine. (Kossel and Kutscber Kossel and Dakin.) Scombrine. (Kossel.) Cyclop terine. (Kosseland Kutscber Kossel Morkowin.] Cyprinine 1. (Kosseland Dakin.) Cyprinine... 

In 1899 Kossel isolated a similar substance from the protamine, clupeine, of herring milt, and since then E. Fischer and his pupils have obtained it from caseinogen, horn and other proteins. The preparation from horn, when racemised, corresponded in properties with the synthetical a-aminoisovalerianic acid. 

A. Kossel und H. D. Dakin. Ober Salmin und Clupein. Zeit. physiol. Chem., 1904,... 

AOT/isooctane Protamines from sperm head nucleoproteins of fish Conformational studies on model polypeptides with amino acid sequences similar to clupeine and salmine were carried out in RMs [286]... 

Inoue, S. and Ando, T. (1970) Interaction of clupeine with deoxyribonucleic acid. I. Thermal melting and sedimentation studies. Biochemistry, 9, 388-394. 

The specific activities of penicillolysin for clupeine and casein hydrolysates were 3.04 x 10 1 and 5.23 x 10 3 katal/kg protein at pH 7.0, respectively (Table 9) [69], The rate of clupeine hydrolysis was 60-fold greater than that for casein hydrolysis. When zinc is removed, the enzyme is completely inactive, and readdition of zinc restores the dual activities towards clupeine and casein (Table 9). Depending on the casein substrate, the cobalt-penicillolysin (Co-penicillolysin) could be up to ca 1.6 times more active than the native zinc enzyme. On the other hand, in clupeine-hydrolysis, the cobalt enzyme is about 70% as active as the native enzyme. Thus, replacement of the zinc-penicillolysin with cobalt markedly decreases the activity towards clupeins while increases it towards casein. 

The rate of clupeine hydrolysis is 60-fold greater than that for casein hydrolysis at pH 7.0. High affinity towards the Pro-j-X, Arg-j-Arg, and hydrophobic residue (Pi)-f-X. 

Preparation and amino acid composition of salmin and clupein. Proc. Soc. Exptl. Biol. Med., 70, 494 (1949). With D. Bolling, H. Gershon, and H. A. Sober. 

Protamines. Strongly basic proteins of low molecular weight (4,000 to 8,000). They are rich in arginine. Examples are clupein from herring and scombrin from mackerel. 

Figure 5. A Scatchard plot showing the binding of clupeine Z to the 51 basoiKiiT DNA sequence. The data were fit using equation 2.

Removal of nucleic acids. Manganese acetate solution (250 ml. of il//10) is added dropwise, with constant stirring, to solution A (990 ml.). After 24 hours of standing at 0°, the suspension is centrifuged for 20 minutes at 16,000 r.p.m. To the supernatant liquor (1160 ml.) is then added 116 ml. of 0.2% clupein sulfate solution (pH 7.0), with constant stirring, and the solution is allowed to stand at 0° for 24 hours. The mixture is centrifuged for 20 minutes at 10,000 r.p.m., and the supernatant liquor (1260 ml. of solution B specific activity, 83,000 yield, 72%) is treated further. 

While the physical characterization of these proteins is still very poor, their chemical composition is well known. Analyses carried out on herring protamine (clupein), on sturgeon protamine (sturine), and on protamines... 

Usually isolated as the sulfate B-2HjSO white powder, [u — 85.49" (said aq soln). One gram dissolves in 80 ml water at room temp. Freely sol in hot water, separates from the supersatd soln on cooling as a clear, colorless oil contg 50% HjO. n 1.4435. Clupeine is split by protaminase, ac-... 

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