College of Natural Resources and Life Science, Dong-A University, Busan 604-714, Republic of Korea.
Biochem Biophys Res Commun. 2013 Jan 4;430(1):144-9. doi: 10.1016/j.bbrc.2012.11.056. Epub 2012 Nov 27.
The honeybee is an important insect species in global ecology, agriculture, and alternative medicine. While chymotrypsin and trypsin inhibitors from bees show activity against cathepsin G and plasmin, respectively, no anti-elastolytic role for these inhibitors has been elucidated. In this study, we identified an Asiatic honeybee (Apis cerana) chymotrypsin inhibitor (AcCI), which was shown to also act as an elastase inhibitor. AcCI was found to consist of a 65-amino acid mature peptide that displays ten cysteine residues. When expressed in baculovirus-infected insect cells, recombinant AcCI demonstrated inhibitory activity against chymotrypsin (K(i) 11.27 nM), but not trypsin, defining a role for AcCI as a honeybee-derived chymotrypsin inhibitor. Additionally, AcCI showed no detectable inhibitory effects on factor Xa, thrombin, plasmin, or tissue plasminogen activator; however, AcCI inhibited human neutrophil elastase (K(i) 61.05 nM), indicating that it acts as an anti-elastolytic factor. These findings constitute molecular evidence that AcCI acts as a chymotrypsin/elastase inhibitor.
蜜蜂是全球生态、农业和替代医学中重要的昆虫物种。虽然蜜蜂中的糜蛋白酶和胰蛋白酶抑制剂分别对组织蛋白酶 G 和纤溶酶表现出活性，但这些抑制剂尚无抗弹性蛋白酶作用的相关报道。在本研究中，我们鉴定出一种亚洲蜜蜂（Apis cerana）糜蛋白酶抑制剂（AcCI），它也表现出弹性蛋白酶抑制作用。AcCI 由 65 个氨基酸的成熟肽组成，显示出 10 个半胱氨酸残基。当在杆状病毒感染的昆虫细胞中表达时，重组 AcCI 对糜蛋白酶（K(i) 11.27 nM）表现出抑制活性，但对胰蛋白酶没有抑制作用，这表明 AcCI 是一种来源于蜜蜂的糜蛋白酶抑制剂。此外，AcCI 对因子 Xa、凝血酶、纤溶酶或组织型纤溶酶原激活物没有检测到抑制作用；然而，AcCI 抑制人中性粒细胞弹性蛋白酶（K(i) 61.05 nM），表明它作为一种抗弹性蛋白酶因子发挥作用。这些发现构成了 AcCI 作为糜蛋白酶/弹性蛋白酶抑制剂的分子证据。
