Fiorucci L, Pallaoro M, Erba F, Colombo A P, Rholam M, Cohen P, Ascoli F
Department of Experimental Medicine and Biochemical Sciences, University of Roma Tor Vergata, Italy.
Comp Biochem Physiol B Biochem Mol Biol. 1998 Jun;120(2):239-45. doi: 10.1016/s0305-0491(98)10013-5.
Some structural features of bovine tryptase were discussed based on spectroscopic analysis. The far UV-CD spectrum of the enzymatically active bovine tryptase is consistent with a structure containing very little, if any alpha-helix, as found for other serine proteases. The analysis of near UV-CD and UV absorption spectra reveals the presence of a high number of Trp residues arranged probably in strong structural motifs. At variance with other tryptases, the bovine enzyme shows an electrophoretic behaviour in native and denaturating conditions compatible with an association state larger than a tetramer (probably a dodecamer). From a biochemical point of view, the bovine tryptase shares with the human counterpart, the preference for cleaving substrates bearing dibasic cleavage sites. Thus, it is hypothesized that tryptase may be involved in some proprotein processing mechanism(s).
基于光谱分析讨论了牛胰蛋白酶的一些结构特征。具有酶活性的牛胰蛋白酶的远紫外圆二色光谱与其他丝氨酸蛋白酶一样，其结构中几乎不含α-螺旋（如果有的话）。近紫外圆二色光谱和紫外吸收光谱分析表明，存在大量可能排列在强结构基序中的色氨酸残基。与其他胰蛋白酶不同，牛胰蛋白酶在天然和变性条件下均表现出电泳行为，这与大于四聚体（可能是十二聚体）的缔合状态相符。从生化角度来看，牛胰蛋白酶与人类胰蛋白酶一样，倾向于切割带有双碱性切割位点的底物。因此，推测胰蛋白酶可能参与某些前体蛋白加工机制。
