Section of Biochemistry and Clinical Biochemistry, Department of Biochemistry and Molecular Biology, University of Ferrara, Via Luigi Borsari 46, Italy.
J Biochem. 2012 May;151(5):493-9. doi: 10.1093/jb/mvs014. Epub 2012 Feb 17.
In vitro activation of matrix metalloproteinase-9 (MMP-9) (Gelatinase B) with MMP-3 shows the presence of two different forms: an 82 kDa, N-terminal truncated form, and a 65 kDa, N- and C-terminal truncated form. So far the presence of the 65 kDa form has not been reported in vivo. Affinity chromatography was performed to separate MMP-9 from MMP-2 and immunoprecipitation to isolate ∼65 kDa MMP-9 from 82 kDa MMP-9 in sera of healthy donors. The presence of ∼65 kDa active MMP-9 was demonstrated both with gelatin zymography and western blot analysis. The ∼65 kDa MMP-9 lacks the haemopexin domain required for the high-affinity binding of the tissue inhibitor TIMP-1, and can be evaluated by activity assay in the presence of TIMP-1. This opens the possibility to investigate the role of this form of MMP-9 that escapes physiological regulation.
基质金属蛋白酶-9（MMP-9）（明胶酶 B）与 MMP-3 的体外激活显示存在两种不同形式：82 kDa、N 端截断形式和 65 kDa、N 和 C 端截断形式。到目前为止，体内尚未报道存在 65 kDa 形式。亲和层析用于从 MMP-2 中分离 MMP-9，免疫沉淀用于从健康供体血清中的 82 kDa MMP-9 中分离约 65 kDa MMP-9。通过明胶酶谱法和 Western blot 分析均证明存在约 65 kDa 活性 MMP-9。约 65 kDa MMP-9 缺乏组织抑制剂 TIMP-1 高亲和力结合所需的血红素结合蛋白结构域，并且可以在 TIMP-1 的存在下通过活性测定进行评估。这为研究这种逃避生理调节的 MMP-9 形式的作用开辟了可能性。
