Lysin species-specificity

The relationship between anemone fish, Amphiprion sp., and their sea anemone partners are regulated by alkaloids from the sea anemone. Amphiprion perideraion is attracted to the sea anemone Radianthus kuekenthali by the simple lysine-derived alkaloid amphikuemin (Fig. 12.6 Murata etal, 1986). Other simple alkaloids, aplysinopsin and dihydroaplysinopsin, also attract A. perideraion, regulate its swimming rate and induce their species-specific partnership. A related anemone fish, Amphiprion ocellaris, is attracted to the sea anemone Stoichactis kenti by tyramine (Fig. 12.6) and tryptamine induces searching by the fish (Murata etal, 1986). 

All of the core histones share a conserved 65-residue histone fold.27 28 The arginine-rich histones have a strongly conserved amino acid sequence, histone H4 from pea seedlings differing from that of the bovine thymus by only two amino acids. On the other hand, the lysine-rich HI is almost species-specific in its sequence. Differentiated tissues contain at least seven variant forms of histone HI including proteins designated HI0, Hit, and H5 29-31... 

Figure 7. Species-specific dissolution of isolated VEs by purified lysins as determined by the light scattering assay. Vertical axis, percent VE dissolved horizontal axis, qg lysin added. R j, VEs from the red abalone, H. rufescens. B j, VEs from the black abalone, H. cracherodii. Pyj, VEs from the pink abalone, H. corrugata. ( ) red lysin (A) pink lysin and ( ) black lysin (from Vacquier and Lee, 1993).

To summarize, variable structural features of lysins suggest ways to attack the elucidation of the molecular mechanism of species-specific sperm-egg recognition in abalones. The invariant structural features of lysins suggest ways to explore the molecular mechanism lysin uses to destroy nonenzymatically the integrity of the VE to allow the sperm to pass through this protective envelope and contact the egg cell membrane. 

Lee, Y.-H. and Vacquier, V.D. (1992). The divergence of species-specific abalone sperm lysins is promoted by positive Darwinian selection. Biol. Bull. 7S2 97-105. 

Vacquier, V. D., Gamer, K.R., and Stout, C D. (1990). Species-specific sequences of abalone lysin, the sperm protein that creates a hole in the egg envelope. Proc. Natl. Acad. Sci. USA 87 5792-5796. 

Observations, then, suggest that synthetic lysinoalanine derived from lysine can be partly utilized ir vivo as a source of lysine. However, the extent of biological utilization is species-specific, and appears to be quite low in mice. Additional studies are desirable to elucidate this dependence reliably for different animals, especially primates. 

After the introduction of C-labels into the protein or glycoprotein molecule, the ability to assign the resonances to specific carbon atoms is essential. In the case of glycophorin (see Fig. 1), it may readily be seen that 5 lysine residues and 1 N-terminal amino acid (per species) can be reduc-tively di[ C]methylated. This could theoretically lead to 6 resonances (or possibly more, if chemical-shift nonequivalence is observed for the dimethyl species) in the C spectrum of methylated glycophorin A. However, in most cases, the N, N -di[ C]methyllysine resonances all occur near, or at, the same frequency. It is then necessary to be able at least to assign, or... 

Settlement of barnacles, especially the now cosmopolitan species Balanus amphitrite, has received extensive attention. Rittschof53 pioneered the investigation of the role of specific soluble peptides released as metabolites into seawater by adult barnacles as larval-settlement stimuli for invertebrate larvae, especially those of barnacles. Cyprid larvae of B. amphitrite are powerfully stimulated to settle to surfaces and walk upon them by the presence of very low concentrations of dissolved peptides with a C-terminal arginine or lysine residue.53-54 However, there are reports of attachment and metamorphosis of cyprids of B. amphitrite, in the absence of a soluble peptide cue,... 

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