The scallop Argopecten purpuratus is a species of importance for aquaculture in Chile and Peru, but in recent years, they have decreased their growth rates and experienced massive mortalities potentially associated with pathogenic infections. Characterization of proteins involved in the immunity status of A. purpuratus is of interest to develop molecular markers to support its culture. Here we report the characterization of a new Peroxiredoxin (Prx) homologue, the first one identified in A. purpuratus. Prxs are a ubiquitous family of cysteine-dependent peroxidase enzymes that play a dominant role in the regulation of peroxide levels in cells, as rapidly detoxify peroxynitrite, hydrogen peroxide and organic hydroperoxides. The molecular and phylogenetic analyses of this gene showed that it is a new member of the PrxV family, thus, it was designated as ApPrxV. This gene showed to be constitutively expressed in each examined tissue, but at a higher level in the striated adductor muscle. ApPrxV expression was highly upregulated in haemocytes in response to an immune challenge with pathogen bacteria Vibrio splendidus. Overall results indicate that ApPrxV is a constitutive and inducible protein that can play an important role in the immune response of A. purpuratus against bacterial infection. Therefore, the results of this study can (i) provide the bases for future functional studies to assess the health status of A. purpuratus; and (ii) can guide the development of molecular markers for future selective breeding of this bivalve.

扇贝Argopecten purpuratus是智利和秘鲁水产养殖的重要物种，但近年来，它们的生长速度降低，并经历了可能与病原体感染相关的巨大死亡。研究紫癜曲霉免疫状态中涉及的蛋白质的特征对于开发分子标记以支持其培养具有重要意义。在这里，我们报告一种新的过氧化物酶（Prxiredoxin，Prx）同系物的特征，该同系物是紫癜曲霉中发现的第一个同系物。。Prxs是半胱氨酸依赖性过氧化物酶的一个普遍存在的家族，在迅速清除过氧亚硝酸盐，过氧化氢和有机氢过氧化物时，在细胞中过氧化物水平的调节中起主要作用。该基因的分子和系统发育分析表明，它是PrxV家族的新成员，因此被命名为ApPrxV。该基因显示在每个检查的组织中组成性表达，但在横纹肌内收肌中水平较高。ApPrxV的表达高度上调在血细胞中，以响应病原菌细弧菌的免疫挑战。总体结果表明ApPrxV是一种组成型和诱导型蛋白，在紫癜抗细菌感染的免疫反应中起重要作用。因此，这项研究的结果可以（i）为将来的功能研究以评估紫癜健康状况提供基础。（ii）可以指导分子标记的发展，以便将来对该双壳类动物进行选择性育种。