不同数量的2kDa富苯丙氨酸的碱性短肽（BOP）和乙醇酸氧化酶结合

乙醇酸氧化酶（GO）只含40 kD亚基却具有多个等电点（pI）.我们曾报告GO含40 kD酸性亚基和68 kD碱性亚基，组成3种GO同工酶［1~6］.后来证实，68 kD亚基由14个2 kD富苯丙氨酸的碱性短肽（BOP）和40 kD亚基组成［7］.现在进一步证实，不同数量的BOP和乙醇酸氧化酶结合，组成多种GO-BOP复合体GC.这些复合体具有不同的pI、乙醇酸氧化酶活性和吸收曲线，但SDS-PAGE和免疫反应相同.在低电压和短时间的醋酸薄膜电泳中，GO和BOP不会解离，GC呈现强碱性（pI>10.0）；在高电压的毛细管等电聚焦电泳(cIEF)中，GO和BOP发生不同程度解离，导致GC不聚焦，或聚焦为不同带，pI为7.4/6.8/6.2/5.3.BOP存在于各种动植物和微生物以及血纤维蛋白原中.

Plant Glycolate Oxidase Bound to 2 kD Basic Phenylalanine-rich Oligo-peptide（BOP）of Different Quantities

Glycolate oxidase (GO) consists of identical 40 kD subunits, but exhibits variable pI values. We reported that GO contained a 40 kD acidic subunit and a 68 kD basic subunit in plants. Now we knew that the 68 kD was in fact a mixture of 40 kD subunit and 14 molecules of 2 kD basic phenylalanine-rich oligo-peptide (BOP), which widely existed in plant, animal, microorganism and fibrinogen. This study indicated that different quantities of BOP bound to GO might form complexes (GC), with different pI, specific activity and absorption spectra, even the SDS-PAGE and immuno-blotting patterns appeared same. As the dissociation of BOP and GO could be accelerated in electric field, the pI variation of GCs were shown under high-voltage cellulose acetate membrane electrophoresis, but not after in low-voltage/short-time IEF. The intermediates of different amount of BOP dissociated from GO resulted in varied pI of 7.4/6.8/6.2/5.32. The intact GC was highly basic (pI>10.0).