United States Department of Agriculture, Agricultural Research Service, Aquatic Animal Health Research Unit, 990 Wire Road, Auburn, AL 36832-4352, USA.
Fish Shellfish Immunol. 2010 Mar;28(3):504-9. doi: 10.1016/j.fsi.2009.12.007. Epub 2009 Dec 24.
Myeloperoxidase (EC 1.11.1.7), a heme-containing lysosomal glycoprotein, is found predominantly in azurophilic granules of neutrophils. This enzyme upon activation catalyzes hydrogen peroxide in the presence of various halide ions to form hypohalous acids. Subsequently, these reagents are able to kill the invading microorganisms. In this study, we report the identification, characterization and expression analysis of the channel catfish myeloperoxidase transcript. The full-length nucleotide sequence of channel catfish myeloperoxidase cDNA had 3157 nucleotides, including an open reading frame, which appears to encode a putative peptide of 771 amino acid residues with a calculated molecular mass of 87.14 kDa. By comparison with the human counterpart, the channel catfish myeloperoxidase peptide can be divided into domains and has conservative features, including peroxidase catalytic sites, covalent linkage sites for the heme group and all cysteine residues. The channel catfish myeloperoxidase transcript was detected by RT-PCR in anterior kidneys, where the major leukocyte population is neutrophil precursors. Reagent development and the role of this enzyme in Edwardsiella ictaluri infection are under investigation.
髓过氧化物酶（EC 1.11.1.7），一种含血红素的溶酶体糖蛋白，主要存在于中性粒细胞的嗜天青颗粒中。该酶在激活后，可在各种卤化物离子存在的情况下催化过氧化氢形成次卤酸。随后，这些试剂能够杀死入侵的微生物。在这项研究中，我们报告了鲫鱼髓过氧化物酶转录本的鉴定、特性和表达分析。鲫鱼髓过氧化物酶 cDNA 的全长核苷酸序列有 3157 个核苷酸，包括一个开放阅读框，似乎编码一个推测的肽，由 771 个氨基酸残基组成，计算分子量为 87.14kDa。与人类对应物相比，鲫鱼髓过氧化物酶肽可以分为结构域，具有保守特征，包括过氧化物酶催化位点、血红素基团和所有半胱氨酸残基的共价连接位点。通过 RT-PCR 在鱼的前肾中检测到鲫鱼髓过氧化物酶的转录本，前肾是白细胞的主要群体，是中性粒细胞前体。正在开发该酶的试剂和在爱德华氏菌感染中的作用。
