Author:
Kanoh Satoshi,Noma Takayuki,Ito Hirotaka,Tsureyama Masatomo,Funabara Daisuke
Abstract
AbstractMarine elasmobranch fish contain urea, a protein denaturant, in their bodies. The urea-trimethylamine N-oxide (TMAO) counteraction mechanism contributes to urea-resistibility, where TMAO compensates for protein denaturation by urea. However, previous studies revealed that shark fast skeletal muscle myosin exhibits native activity at physiological urea concentrations in the absence of TMAO, suggesting that shark myosin has urea-resistibility. In this study, we compared the urea-resistibility of myosin alkali light chains (A1-LC and A2-LC) from banded houndshark and carp by examining the α-helical content at various urea concentrations. The α-helical content of carp myosin A1-LC and A2-LC gradually decreased as urea concentrations increased to 2 M. In contrast, the α-helical content of banded houndshark A1-LC increased between 0 and 0.5 M urea, and the α-helical content of A2-LC remained constant until 0.5 M urea. We determined the full-length sequences of the banded houndshark myosin light chains (A1-LC, A2-LC and DTNB-LC). Hydrophilicity analysis revealed that the N-terminal region (residues 28–34) of A1-LC from banded houndshark is more hydrophilic than the corresponding region of A1-LC from carp. These findings support the notion that shark myosin exhibits urea-resistibility independent of the urea-TMAO counteraction mechanism.
Publisher
Springer Science and Business Media LLC
Reference36 articles.
1. Holmes, W. N. & Donaldson, E. M. The body compartments and the distribution of electrolytes. In Fish Physiology (eds Hoar, W. S. & Randall, D. J.) 1–89 (Academic Press, 1969).
2. Watabe, S., Ochiai, Y., Kanoh, S. & Hashimoto, K. Proximate and protein compositions of requiem shark muscle. Nippon Suisan Gakkai Shi 49, 265–268 (1983).
3. Hermans, J. Jr. The effect of protein denaturants on the stability of the α Helix1. J. Am. Chem. Soc. 88, 2418–2422 (1966).
4. Watlaufer, D. B., Malik, S. K., Stoller, L. & Coffin, R. L. Nonpolar group participation in the denaturation of proteins by urea and guanidinium salts. Model compound studies. J. Am. Chem. Soc. 86, 508–514 (1964).
5. Finer, E. G., Franks, F. & Tait, M. J. Nuclear magnetic resonance studies of aqueous urea solutions. J. Am. Chem. Soc. 94, 4424–4429 (1972).
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献