贻贝前足丝收缩肌中生物活性肽的进一步鉴定：两种收缩肽和三种抑制肽。

Further identification of bioactive peptides in the anterior byssus retractor muscle of Mytilus: two contractile and three inhibitory peptides.

Fujisawa Y, Takahashi T, Ikeda T, Muneoka Y, Kubota I, Minakata H, Nomoto K, Nose T, Miki W

Faculty of Integrated Arts and Sciences, Hiroshima University, Japan.

Comp Biochem Physiol C Comp Pharmacol Toxicol. 1993 Sep;106(1):261-7. doi: 10.1016/0742-8413(93)90281-o.

Abstract

Two contractile and three inhibitory peptides were newly isolated from the anterior byssus retractor muscles (ABRMs) of the bivalve mollusc Mytilus edulis by using the muscle as the bioassay system. 2. The structures of the two contractile peptides were GPFGTHIKamide (GPFG-8) and GPFGLNKHGamide (GPFG-9). The contractile response of the ABRM to the first-time application of GPFG-8 or GPFG-9 was of considerable size. The threshold concentrations of the peptides were around 10(-9) M. However, the contractile response to the second-time application was far smaller than that to the first-time application in both cases. Namely, the muscle showed tachyphylaxis to the peptides. 3. Two of the three inhibitory peptides were members of the Mytilus-inhibitory-peptide (MIP) family. Their structures were RAPLFIamide (MIP6) and RSPMFVamide (MIP7). The peptides, as well as the other MIPs previously identified, showed a potent inhibitory effect on phasic contraction of the ABRM in response to repetitive electrical stimulation. The remaining one was an MIP-related peptide (MIP-RP) having the sequence of MRYFVamide. The MIP-RP was less potent than the two MIPs in inhibiting the contraction of the ABRM.

摘要

利用双壳贝类贻贝的前足丝收缩肌（ABRMs）作为生物测定系统，从该肌肉中新分离出两种收缩肽和三种抑制肽。2. 两种收缩肽的结构分别为GPFGTHIKamide（GPFG - 8）和GPFG - LNKHGamide（GPFG - 9）。ABRM对首次应用GPFG - 8或GPFG - 9的收缩反应幅度较大。这些肽的阈值浓度约为10^(-9) M。然而，在两种情况下，对第二次应用的收缩反应都远小于对第一次应用的反应。也就是说，肌肉对这些肽表现出快速耐受性。3. 三种抑制肽中的两种是贻贝抑制肽（MIP）家族的成员。它们的结构分别为RAPLFIamide（MIP6）和RSPMFVamide（MIP7）。这些肽以及先前鉴定的其他MIPs，对ABRM在重复电刺激下的相位收缩表现出强大的抑制作用。剩下的一种是具有MRYFVamide序列的MIP相关肽（MIP - RP）。MIP - RP在抑制ABRM收缩方面的效力低于两种MIPs。