Human β-defensins are an important family of innate host defense peptides with pleiotropic activities. Human β-defensin 36 (DEFB136) is a novel member of the β-defensin family which have not been characterized so far. In the present research, the DEFB136 peptide was expressed successfully and purified using the IMPACT-TWIN 1 expression system. The purified DEFB136 peptide was identified by MALDI-TOF mass spectrometry and circular dichroism spectroscopy. While the recombinant DEFB136 peptide exhibited a broad spectrum of antimicrobial activity against E. coli, Staphylococcus aureus and Candida albicans strains, but had low cytotoxicity to human erythrocytes. In addition, the result of the octet assay showed that the DEFB136 had a high lipopolysaccharide (LPS)-binding affinity, suggesting the DEFB136 may be involved in immunoregulation through its LPS neutralization. These results may help lay the groundwork to understand better the complex interaction between innate host defense and the diversity of the defensin family.

人类β-防御素是具有多效活性的先天宿​​主防御肽的重要家族。人类 β-防御素 36 (DEFB136) 是 β-防御素家族的一个新成员，目前尚未被表征。在本研究中，使用 IMPACT-TWIN 1 表达系统成功表达并纯化了 DEFB136 肽。纯化的 DEFB136 肽通过 MALDI-TOF 质谱和圆二色光谱进行鉴定。虽然重组 DEFB136 肽对大肠杆菌、金黄色葡萄球菌和白色念珠菌表现出广谱的抗菌活性菌株，但对人红细胞具有低细胞毒性。此外，八位组分析的结果表明 DEFB136 具有高脂多糖 (LPS) 结合亲和力，表明 DEFB136 可能通过其 LPS 中和参与免疫调节。这些结果可能有助于为更好地理解先天宿主防御与防御素家族多样性之间的复杂相互作用奠定基础。