人血小板生成素全长分子在酵母系统中的分泌表达及活性分析

外源基因可通过整合型载体被整合到毕赤酵母（Ｐｉｃｈｉａｐａｓｔｏｒｉｓ）染色体上,获得遗传性稳定分泌表达株．利用酵母信号肽ＭＦα,对该信号肽蛋白酶识别位点的相关序列进行重新设计,使天然人ＴＰＯ成熟肽在毕赤酵母系统中分泌表达成功．表达产物经Ｗｅｓｔｅｒｎ－ｂｌｏｔ进行分析,分子量约为６６ｋＤ处蛋白条带可被ＴＰＯ抗体识别;表达量约为０．１ｇ／Ｌ;Ｎ端氨基酸序列分析结果与设计的一致;表达产物对小鼠骨髓细胞形成巨核细胞集落形成单位（ｍｅｇａｋａｒｙ－ｏｃｙｔｅｃｏｌｏｎｙｆｏｒｍｉｎｇｕｎｉｔ,ＣＦＵ－Ｍｅｇ）具有明显的刺激作用．     

人肝金属硫蛋白-I_A基因在鱼腥藻中的克隆与表达

将人工合成的人肝金属硫蛋白（ｍｅｔａｌｏｔｈｉｏｎｅｉｎ,简称ＭＴ）－ＩＡ基因插入至中间载体ｐＲＬ－４３９上强启动子ｐｓｂＡ后,再将其与穿梭载体ｐＫＴ－２１０相连,得到大肠杆菌－蓝藻穿梭表达载体ｐＫＴ－ＭＴ,用三亲接合转移法将ｐＫＴ－ＭＴ转入丝状体蓝藻－鱼腥藻７１２０,经链霉素筛选,得到了稳定的转人肝ＭＴ－ＩＡ基因鱼腥藻．纯化单藻落,液体扩大培养．从鱼腥藻中提取的质粒经Ｓｏｕｔｈｅｒｎ印迹分析,确定人肝ＭＴ－ＩＡ基因已转入鱼腥藻７１２０中,Ｗｅｓｔｅｒｎ印迹分析表明,金属硫蛋白在转人肝ＭＴ－ＩＡ基因鱼腥藻中得到了表达．经原子吸收光谱法测定表达量约为７００μｇＭＴ／ｇ鲜藻,重金属耐受性实验表明,得到了能耐受重金属－镉的转人肝ＭＴ－ＩＡ基因鱼腥藻,它将在清除水域中重金属污染和医药研究方面发挥重要作用．     

Short Compilation of Published Reaction Rate Data for Catalytic Hydrogenations in Supercritical Fluids

In this work, a short compilation is presented on heterogeneously catalyzed hydrogenations carried out in near‐critical fluids. Reactions carried out in supercritical fluids, catalyzed by supported Pd, Ni or Cu, are considered as green processes in view of their negligible impact on the environment. A number of technologies are already available for clean hydrogenations, mostly performed in carbon dioxide as a dense solvent in continuous reactors. However, propane and other lower alkane solvents can perform as well as carbon dioxide but at much lower pressures. We review their behaviors in this paper in terms of observed reaction rates, space velocities, selectivities and apparent kinetic constants. In the case of vegetable oils, data are available on the effect of pressure and reaction conditions on the selectivity toward the preferred cis‐isomer during linoleic hydrogenation.     

Ultrastructural Study of Secondary Wall Formation in the Stem Fiber of Phyllostachys pubescens

Ultrastructural changes in secondary wall formation of Phyllostachys pubescens Mazel fiber were investigated with transmission electron microscopy. Fiber developed initially with the elongation of cells containing ribosomes, mitochondria and Golgi bodies in the dense cytoplasm. During the wall thickening, the number of rough endoplasmic reticulum and Golgi bodies increased apparently. There were two kinds of Golgi vesicles, together with the ones from endoplasmic reticulum formed transport vesicles. Many microtubules were arranged parallel to the long axis of the cell adjacent to the plasmalemma. Along with the further development of fiber, polylamellate structure of the secondary wall appeared, with concurrent agglutination of chromatin in the nucleus, swelling and disintegration of organelles, while cortical microtubules were still arranged neatly against the inner side of plasmalemma. Lomasomes could be observed between the wall and plasmalemma. The results indicated that the organelles, such as Golgi bodies together with small vesicles, rough endoplasmic reticulum and lomasomes, played the key role in the thickening and lignification of the secondary wall of bamboo fiber, though cortical microtubules were correlative with the process as well.     

Pyrazole and (pyrazol-1-yl)metal complexes as carbon-carbon coupling catalysts

Pyrazolyl ligands have been used to prepare metal complexes since the mid-1960s as nitrogen-donor ligands. However, unlike other nitrogen-donor ligands like imines and pyridines, their metal complexes have not been used extensively in catalysis. This review highlights the emergence of pyrazolyl metal complexes as nitrogen-donor catalysts, particularly in carbon-carbon coupling reactions. The focus is on olefin oligomerization and polymerization, acetylene oligomerization and polymerization, Heck and Suzuki coupling and ring opening polymerization of cyclic monomers. It highlights successes and problems of these catalysts, but draws attention to this burgeoning area so that other researchers can take advantage of these remarkable ligands.     

Guanidines from ‘toxic substances’ to compounds with multiple biological applications – Detailed outlook on synthetic procedures employed for the synthesis of guanidines

Guanidines to begin with, were thought of being harmful substances associated with medical ailment. With the advent of World War I and the impact it left on the populations at large research focus was shifted, towards polymer synthesis and that too on plastics and rubbers which were mostly employed in various artillery equipments. In the surge, to get plastics and rubbers with enhanced mechanical properties, many variedly substituted guanidines used as accelerators in vulcanization of polymers were synthesized using different procedures. Continuous research on guanidines, led scientists to develop different protocols and routes for the synthesis of these compounds, later these were tested for their possible use in various areas and now these are sought for their enhanced biomedical and catalytic applications. This review article presents thirty six different synthetic procedures employed for the synthesis of guanidines over the years including seventy schemes and a brief account on the reported wide ranging applications of some novel guanidines.