IMMUNOLOGICAL STUDIES OF THE RAT OLFACTORY MARKER PROTEIN1

Abstract— Antisera against the rat olfactory marker protein were prepared by injection of the homogeneous protein into a goat and a rabbit. When the antisera were tested by immunodiffusion against olfactory tissue extracts, many but not all mammalian species cross-reacted against these antisera. Immunoprecipitin titrations with the goat antiserum generally showed higher cross-reactivity against olfactory extracts from species more closely related to the rat. Human olfactory bulb extracts and non-mammalian olfactory tissue extracts did not cross-react with the antisera by either immunodiffusion tests or immunoprecipitin titrations, however, they did cross-react when tested by a competitive binding radioimmunoassay using tritium-labelled purified rat protein and the goat antibody. The olfactory marker protein which is an example of a brain protein specific to one cell, the olfactory chemoreceptor neuron, has a very wide species distribution, being present in rat, mouse, hamster, guinea-pig, sheep, cow, rabbit, pig, dog, man, frog and garfish. Therefore it presumably plays an important and unique role related to the function of this primary chemosensory neuron.     

IMMUNOLOGICAL AND ULTRASTRUCTURAL CHARACTERIZATION OF THE PHOTOSYNTHETIC COMPLEXES OF THE PROCHLOROPHYTE PROCHLOROCOCCUS (OXYCHLOROBACTERIA)

Ultrastructural features and immunological properties of some thylakoid proteins were examined in two strains of the prochlorophyte Prochlorococcus and compared to those of other photosynthetic prokaryotes and eukaryotes. Both strains exhibited two or three rows of tightly appressed thylakoidal membranes, located at the cell periphery. However, thylakoids were concentrically arranged in the strain from the Sargasso Sea (SARG) and horseshoe-shaped in the Mediterranean isolate (CCMP 1378). Although lacking phycobilisomes, both cell types shared with cyanobacteria the presence of carboxysome-like structures and glycogen granules as storage compounds. The main thylakoid polypeptides separated by sodium dodecyl sulfate—polyacrylamide gel electrophoresis were characterized by Western blotting using several antibodies. The 30-kDa polypeptide of the light-harvesting complex (LHC) of Prochlorococcus showed a weak positive immunological cross-reaction with an antibody raised against the 32-kDa apoprotein of the LHC of the prochlorophyte Prochlorothrix hollandica. In contrast, it showed no immunological relationships with the chlorophyll a/b (Chl a/b) LHCs of green algae and higher plants. Protein membranes from Prochlorococcus strongly cross-reacted with antibodies raised against reaction center polypeptides of photosystems II and I (PSs II and I) of other photosynthetic organisms, confirming the high degree of conservation of these basic compounds of the photosynthetic machinery during evolution. Immunolocalization of thylakoid proteins showed that the LHC proteins, the major PS II reaction center proteins (CP 43 and D2), and the PS I reaction center proteins were equally distributed within the thylakoid membranes in contrast to the segregation observed in higher plants and green alga thylakoids. We also identified ribulose-1, 5-bisphosphate carboxylase/oxygenase in the carboxysomes. These results suggest that Prochlorococcus is more closely related to cyanobacteria than to green plastids even though it contains Chl b.     

八肋游仆虫胞质核糖体蛋白基因序列特征分析

为了探讨八肋游仆虫(Euplotes octocarinatus)核糖体蛋白基因的数目及其结构的特殊性, 研究通过生物信息学方法, 对八肋游仆虫胞质核糖体蛋白进行了系统的分析。共鉴定得到98个基因编码78种不同的胞质核糖体蛋白。其中19种胞质核糖体蛋白基因发生了复制, 尽管都是有功能的, 但其中一个基因的表达受到限制。通过与高等真核生物比较, 我们发现: 八肋游仆虫核糖体蛋白eS30缺失了N端的类泛素结构域, eL6缺失了N端的Ribosomal_L6e_N结构域。另外, 不同于其他高等真核生物, 八肋游仆虫酸性核糖体磷酸化蛋白uL10为碱性蛋白。研究为进一步探讨低等真核生物核糖体的组装及功能奠定了基础。     

THE ISOLATION AND PARTIAL CHARACTERIZATION OF THE PYRENOID PROTEIN OF EREMOSPHAERA VIRIDIS

The pyrenoids of Eremosphaera viridis, a green alga, were isolated by density gradient centrifugation and their physical and enzymatic properties were studied. The ultraviolet absorption spectrum of sodium dodecyl sulfate (SDS) extracts of pyrenoids showed a single peak at a wavelength of 277 nm, indicating the presence of protein and the probable absence of nucleic acid. Upon electrophoresis on polyacrylamide gels containing SDS, 16 bands were resolved of which two, together, accounted for 90% of the total protein on the gels. The molecular weights of these two proteins were estimated to be 59,000 and 12,300 and the ratio by weight of the larger to the smaller protein was found to be 2:1. The physical and enzymatic properties of these two proteins were found to closely resemble the properties reported in the literature for the subunits of fraction I protein. Both pyrenoids and fraction I protein are localized in the chloroplast, and both have two principal protein components. The molecular weights and relative ratio of the two pyrenoid components are very similar to those of the two components of fraction I protein. The pyrenoid was found to contain a high specific activity of ribulose-1,5-diphosphate carboxylase which is the same enzymatic activity exhibited by fraction I protein. The presence of ribose-5-phosphate isomerase and ribulose-5-phosphate kinase activities was also noted in pyrenoid preparations. It is suggested that the pyrenoid contains fraction I protein and possibly other enzymes of the Calvin-Bassham carbon dioxide fixing pathway.     

A DIFFERENTIAL GEOMETRIC APPROACH TO PROTEIN STRUTURE ALIGNMENT

A new method of comparing protein structures is deseribed, based on the differential-geometric representaion of protein conformation with the information of global dissimilarity and residue relatedness.The utility of this method for comparing closely and distantly related homologous proteins is demostrated by multiple alignment of globins, serine proteinases and aspartic proteinases.     

苏云金芽胞杆菌YBT1520杀虫晶体蛋白基因的属性

通过Ｓｏｕｔｈｅｒｎ杂交发现高毒力苏云金芽胞杆菌（Ｂａｃｉｌｌｕｓ ｔｈｕｒｉｎｇｉｅｎｓｉｓ）ＴＢＴ－１５２０菌株含有两个杀虫晶体蛋白基因片段,其５’＝末端所在ＨｉｎｄⅢ片段分别为６．８ｋｂ和４．６ｋｂ,它们对应的基因分别命名为ｃｒｙ２１８和ｃｒｙ４．６。经ＰＣＲ鉴定,该菌含有ｃｒｙ１Ａａ、ｃｒｙ１Ａｂ和ｃｒｙ１Ａｃ基因,以及ｃｒｙ２基因,其中ｃｒｙ２１８属于ｃｒｙ１Ａｃ。分析了ｃｒｙ１Ａｃ基因     

论季雨林的水平地带性

季雨林是受制于湿度因子的经度地带性植被类型,它是随着湿度条件的下降由热带雨林向热带疏林过渡的居间类型,而不是受制于温度因子的纬度地带性植被类型,不是随着温度条件的下降由热带雨林向亚热带常绿阔叶林过渡的居间类型。我国南亚热带的榕树群系、黄桐群系,以及热带北缘的青皮群系均不应是季雨林,前二者是典型的南亚热带低地常绿阔叶林或南亚热带雨林,后者则是热带雨林的一分类群。     

关于连鬓胡子遗传方式的探讨

为了探讨连鬓胡子的遗传方式，对７９个连鬓胡子家系进行了调查和分析。初步认为连鬓胡子是常染色体显性基因控制的限性遗传。     

中心体蛋白Cenexin在大鼠精子发生过程中的表达特征

中心体蛋白Cenexin是成熟中心粒的唯一标志分子。为阐明中心粒在大鼠精子发生过程中的成熟以及功能,我们首先通过RT-PCR技术从大鼠睾丸组织中扩增出了Cenexin cDNA片段,原核表达重组蛋白后,用其免疫小鼠制备了高滴度的抗Cenexin的多克隆抗体,然后利用免疫荧光染色、Western Blot和半定量RT-PCR方法,研究了大鼠精子发生过程中Cenexin蛋白和基因的表达特征。结果显示Cenexin mRNA水平在精原细胞和精母细胞中较高,随后表达水平下降,而蛋白质分子在精原细胞到精子细胞中都定位于细胞的一个中心粒上,表示有成熟中心粒的存在,在长形精子细胞中该蛋白位于鞭毛的基体部。附睾的绝大多数成熟精子中Cenexin免疫染色消失。中心体蛋白Cenexin在精子变态期的表达变化可能与精子鞭毛形成的起始有关。     

淋球菌主要外膜蛋白的部分纯化与鉴定

应用国产十六烷基三甲基溴化铵提取淋球菌外膜蛋白Ｉ（ＰＩ）,继用Ｓｅｐｈａｒｏｓｅ ６Ｂ纯化,并通过ＳＤＳ－ＰＡＧＥ鉴定所提ＰＩ的纯度,以及用琼脂双扩散法测定其抗原性。该法提取淋球菌ＰＩ的纯度高,收获量大,对抗原结构无破坏,适宜在淋球菌的生物学研究中应用。     

杜仲皮中抗真菌蛋白的分离和特性研究

从杜仲（ＥｕｃｏｍｍｉａｕｌｍｏｉｄｅｓＯｌｉｖ）皮中分离纯化到一种新的抗真菌蛋白（ＥｕｃｏｍｍｉａＡｎｔｉｆｕｎｇａｌＰｒｏｔｅｉｎ）,简称ＥＡＦＰ。将切碎的杜仲树皮用ＮａＣｌ溶液在组织捣碎器中高速匀浆提取,经硫酸铁沉淀、ＣＭ一ｃｅｌｌｕｌｏｓｅ离子交换层析和Ｂｉｏ一ｇｅｌ一ｐ一１０凝胶层析纯化。如此纯化而得的ＥＡＦＰ在ＳＤＳ－ＰＡＧＥ胶片上显示一条分子量为５．０ｋＤ的单一带。反相ＨＰＬＣ显示４样品是纯的。等电聚焦电泳测得其ｐＩ值大于１１．０。经还原和氨酰羧甲基化处理,用ＨＰＬＣ层析证明ＥＡＦＰ为单链。用酚一硫酸法未测出其含糖。ＥＡＦＰ是简单单链蛋白。氨基酸组成分析结果表明它宫含Ａｒｇ、Ｃｙｓ和Ｇｌｙ,不含Ｍｅｔ,Ｌｙｓ,Ｔｒｐ,Ｈｉｓ和Ｐｈｅ。未经热变性或ＳＤＳ处理的ＥＡＦＰ与考马氏亮蓝试剂不发生显色反应。手工Ｅｄｍａｎ降解法测得Ｎ一端３个氨基酸残基的顺序为Ｇｌｙ一Ａｓｐ一Ａｌａ。用羧肽酶Ａ和Ｂ酶解ＥＡＦＰ测得其Ｃ一末端为Ｖａｌ．０．３ｍｇ／ｍＬ蛋白明显抑制木霉、小麦赤霉菌、烟草黑茎病菌和棉花枯萎病菌菌丝的生长。蛋白在沸水中保温３０ｍｉｎ活性不变。