Lysin positive selection

Y.-H. and Vacquier, V.D. (1995). Evolution and systematics in Haliotidae (Mollusca, Gastropoda) Inferences from DNA sequences of sperm lysin. Marine Biology 724 267-279. Y.-H., Ota,T., and Vacquier, V.D. (1995). Positive selection is a general phenomenon in the evolution of abalone sperm lysin. Molecular Biology and Evolution 72 231-239. 

LCVMS experiment was conducted with an Agilent llOOLC/MSD system. A CTC PAL autosampler from LEAP Technologies was used to introduce samples to the LC/MSD. Polaris 2000 C18 columns packed with 3 pm particles, 30 x 3 mm (i.d.) at 60°C were selected for the study. Flow rate was ImL/min, linear gradient starting form 100% water (0.05% formic acid) to 100% acetonitrile (0.05% formic acid) in 4 minutes. ESI source with positive selected ion monitoring mode (SIM) was employed to detect the corresponding ions of standard compounds. The positive ions (w/z) of 369, 371, 459, and 591 were selected to monitor Mono-Fmoc-Lysine, Bis-Cbz-Lysine, Fmoc-Cbz-Lysine, and Bis-Fmoc-Lysine separately. The mass spectra of standard compounds are shown in Figure 9.24. Four levels of calibration— 25 picomolar, 50 picomolar, 100 picomolar, and 200 picomolar of standard compounds— were used in the quantitation method. 

Fig. 10. The mechanism of site-selective amidation of lysine residues in folded hehcal structures with His (i) Lys (i -t 4 or i-3) sites. The ester is typically p-nitrophenyl but can also be e.g. JV-hydroxysuccinimidyl. Ornithine and diaminobutyric acid residues will also be amidat-ed in the described positions...

Several 0-aminoacyl sugars were prepared to study a relationship between taste and chemical structure. Methyl a-D-glucopyranoside, methyl a-D-galactopyranoside and methyl a-D-mannopyranoside were selected as sugar skeletons. As basic amino acids, esters of lysine, ornithine, a,Y-diaminobutyric acid, and a,p-diaminopropionic acid were introduced into 2-0-, 3-0-, and 4-0- positions of sugars leaving only 6-hydroxyl group free. The results of sensory analysis are list in Table VI. O-... 

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