光学蛋白质芯片检测乳腺癌胸苷磷酸化酶的初步研究

目的应用我国自行研制的无标记光学蛋白质芯片检测乳腺癌组织中的胸苷磷酸化酶(Thymidine phosphorylase,TP),为建立一种快速、简便的临床检测方法进行初步探索。方法将 TP 的多克隆抗体固定于已经过表面改性的固相光学抛光硅片表面上制备无标记光学蛋白质芯片,通过椭偏光学显微成像技术检测20例经病理证实的乳腺浸润性导管癌组织标本和正常组织标本中 TP 水平,以芯片灰度值表示组织中 TP 浓度高低。同时应用 ELISA 方法测定,并比较两种方法检测结果的一致性。结果 20例癌组织的灰度值35.40±11.55,20例正常组织的灰度值为26.80±8.78,两组间差异具显著性意义(P<0.05)。以44.36(正常组织平均值+2倍标准差)为阈值,乳腺癌检测的灵敏度为20.00%,特异度为100.00%。同 ELISA 检测结果相比,在20例乳腺癌组织标本检测中,两种方法的一致性具极显著意义(P<0.01)。结论我国首创的椭偏光学显微成像技术简单、直观,结合光学蛋白质芯片可用于胸苷磷酸化酶的临床检测。

The functional divergence of two glgP homologues in Synechocystis sp PCC 6803

Glycogen phosphorylase (GlgP, EC 2.4.1.1) catalyzes the cleavage of glycogen into glucose-1-phosphate (Glc-1-P), the first step in glycogen catabolism. Two glgP homologues are found in the genome of Synechocystis sp. PCC 6803, a unicellular cyanobacterium: sll1356 and slr1367. We report on the different functions of these glgP homologues. sll1356, rather than slr1367, is essential for growth at high temperatures. On the other hand, when CO2-fixation and the supply of glucose are both limited, slr1367 is the key factor in glycogen metabolism. In cells growing autotrophically, sll1356 plays a more important role in glycogen digestion than slr1367. This functional divergence is also supported by a phylogenetic analysis of glgP homologues in cyanobacteria.