西北地区甘草根瘤菌的表型多样性研究*

选用分离自西北干旱、半干旱地区的甘草根瘤菌68株和34株参比菌株,进行了113项表型性状测定,结果表明：不同地理来源、同一地理来源、甚至同一植株不同根瘤菌株在碳氮源利用、抗生素敏感性、抗逆性等方面存在着差异。部分菌株具有较强的耐盐耐碱能力,其中有5株和1株菌分别能耐受50g／L、60g／L的NaCl2有43％的菌株能在初始DH12的YMA培养基上生长。从数值分类树状图谱发现,在85．5％的相似水平上供试菌株构成了3个表观群。群I有27株菌,除4株来自陕西外,其余均来自新疆。群Ⅱ有4株菌,皆来自陕西。群Ⅲ有8株菌,6株来自陕西,2株来自宁夏,它们与R．hainanense聚在一起。而群I、群Ⅱ没有与参比菌株聚在一起,可能是新的表观群,其分类地位需进一步确定。     

山东省根瘤菌表型多样性及数值分析

在山东省根瘤菌资源调查的基础上,选取31株快生根瘤菌和34株参比菌株,进行了102项表型性状测定和聚类分析。结果表明：不同地理来源、甚至同一地区来源或同种寄主的不同菌株在碳氮源利用、抗生素抗性、耐逆性等方面存在着较高的多样性。32% 的菌株可耐受300 μg/mL的新霉素,39%的菌株可耐受300 μg/mL的青霉素和洁霉素。2株菌能耐受4.0% 的NaCl。13株菌可以在pH11的条件下生长。在87％的相似水平上,未知菌株形成2个独立的亚群,第1亚群有3株菌,中心菌株为SD109;第2亚群有4株菌,中心菌株为SD083。     

我国蚕豆根瘤菌的数值分类及其16SrDNA PCR-RFLP研究

对分离自我国11个省24个地区49株蚕豆根瘤菌及11株参比菌株进行了唯一碳源、氮源、抗生素、耐逆性和酶活性等138个表型性状测定,并用MINTS软件进行聚类分析。结果表明,全部供试菌株在59％的相似水平上聚在一起,在80％的相似水平上可分为6个群。其中群4与参比菌株聚在一起,而其他5个群均由未知菌组成。进一步对36株菌进行了16S rDNA PCR—RFLP分析,在85％相似水平上供试菌可分为4个群和1个独立的分支,其聚群结果与数值分类结果有较好的一致性。表型及遗传型分析结果表明,我国蚕豆根瘤菌具有极大的多样性。     

我国蚕豆根瘤菌的数值分类及其16S rDNA PCR-RFLP研究*

对分离自我国11个省24个地区49株蚕豆根瘤菌及11株参比菌株进行了唯一碳源、氮源、抗生素、耐逆性和酶活性等138个表型性状测定,并用M INTS软件进行聚类分析。结果表明,全部供试菌株在59%的相似水平上聚在一起,在80%的相似水平上可分为6个群。其中群4与参比菌株聚在一起,而其他5个群均由未知菌组成。进一步对36株菌进行了16S rDNA PCR-RFLP分析,在85%相似水平上供试菌可分为4个群和1个独立的分支,其聚群结果与数值分类结果有较好的一致性。表型及遗传型分析结果表明,我国蚕豆根瘤菌具有极大的多样性。     

斜茎黄芪根瘤菌表型性状数值分析

对95株斜茎黄芪根瘤菌与15株已知根瘤菌参比菌及5株来自其它寄本植物的根瘤菌一起进行了130项表型性状分析。结果表明：斜茎黄芪根瘤菌具有极大的表型性状多样性。全部供试菌株在83％相似性水平上分为19个表观群,大部分斜茎黄芪根瘤菌独立成群,与参比菌株的表到性状相似性较低;慢生型斜茎黄芪根瘤菌与快生型斜茎黄芪根瘤菌明显分开,分别构成独立的表现群;某些斜茎黄芪根瘤菌具有很强的抗逆性。     

西北部分地区苦马豆根瘤菌的表型多样性研究

将采集自甘肃、新疆、宁夏等地区的苦马豆根瘤,经分离、纯化获得48株未知菌株,并选取7株参比菌株,进行唯一碳、氮源利用、对抗生素及染料抗性、耐盐性、初始pH生长、生长温度范围及酶活性等共113项生理生化测定;采用数值分类方法对未知根瘤菌进行表型多样性分析。结果表明：供试菌株在碳氮源利用、抗生素敏感性、抗逆性等方面存在着差异。该地区苦马豆根瘤菌具有较强的耐盐、耐碱能力,所有菌株均能在初始pH9~12的YMA培养基上生长,35%菌株可耐受6%的NaCl。从数值分类树状图可见,未知供试菌株在56%的相似水平上聚在一起,在72%的相似水平上分为5个表观群。群Ⅰ有39株菌,在74.6%相似水平聚合,中心菌株为CCNWGS0215;群Ⅱ有5株菌,在76%的相似水平聚合,中心菌株为CCNWGS0228;群Ⅳ有2株菌,在81.5%的相似水平聚合,群Ⅲ和群Ⅴ分别只有1株菌,它们与模式株分离,可能为潜在的新种。     

黄芪根瘤菌的多样性分析

选用23株分离自山西、内蒙古、宁夏、甘肃和吉林的黄芪根瘤菌菌株,进行了营养利用、抗生素抗性、耐逆性和酶活性测定,发现不同地区来源、甚至同一地区来源或同种寄主的不同菌株存在着较大的差异,这种不一致现象在来源于甘肃的7株菌中尤为明显,特别是G156、G130和GO13在碳源利用能力方面表现出诸多不同于本多数黄芪根瘤菌的特点。G156、G012和G022能在50℃生长。多数被试菌株在pH11的条件下生长,少数菌株耐4％～5％NaCl,这些结果均说明黄芪根瘤菌是一个极其多样化的类群,它们也明显不同于已知根瘤菌。     

华北及西北地区岩黄芪根瘤菌的表型及遗传多样性

选用分离自河北、内蒙古等5省区的岩黄芪根瘤菌30株及17株已知参比菌株,进行了营养利用、抗生素抗性、耐逆性及生理生化反应等12 5项表型性状研究,所得数值分类树状图表明不同宿主及不同地域的岩黄芪根瘤菌的表型多样性。通过对其中部分菌株进行16 S r DNA PCR- RFL P及BOX- PCR指纹图谱分析,聚类结果表明供试岩黄芪根瘤菌具有遗传多样性。     

分离自鸡眼草和木蓝的根瘤菌分类研究

采用数值分类方法对分离自鸡眼草(Kummerowia)和木蓝(Indigofera)的根瘤菌及已知参比菌株进行聚类分析,发现在83%的相似性水平上形成2个不同与已知菌种的新类群。以SDS全细胞蛋白电泳技术快速聚类分群扩大菌株数,在86%的相似性水平上,分离自鸡眼草的24株菌形成第1类群,分离自木蓝的20株菌形成第2类群。DNA同源性测定结果表明,这2个类群中心菌株SH713和SHL042与13个已知根瘤菌种的DNA同源性均小于61%。因此,分离自鸡眼草和木蓝的根瘤菌分别构成2个独立的根瘤菌新种群。     

新疆苦豆子根瘤菌的数值分类研究

苦豆子(Sophora alopecuroides)对于干旱荒漠地区的畜牧业发展有着非常重要的意义,其生长特性与根瘤菌有密切关系。我们对分离自新疆苦豆子根瘤的67株根瘤菌及36个模式菌株进行了118项表型性状的测定,包括唯一碳源利用、唯一氮源利用、对抗生素和染料的抗性、耐盐性、初始pH值生长范围、生长温度范围及石蕊牛奶反应、氧化酶、过氧化氢酶和脲酶。对测定结果用聚类分析方法进行了分析,获得数值分类树状图。结果表明：新疆苦豆子根瘤菌在碳氮源利用、抗生素敏感性以及对染料的抗性程度等方面存在着差异。新疆苦豆子根瘤菌能耐受低温,并具有较强的耐盐、碱能力,所有供试菌株均能在初始pH值为9－12的YMA培养基上生长,92.5％的菌株能耐受3.0％的NaCl,91.0％的菌株能耐受4.0％的NaCl,有18株菌甚至能耐受5.0％和6.0％的NaCl。聚类结果表明, 在84.8%的相似性水平上,67个供试菌株构成了4个新的表观群,第Ⅰ、Ⅱ、Ⅲ、Ⅳ类群分别有21、7、4、3个菌株,中心菌株分别为NWBC152、NWTKX101、NWYJS12、NWLP112。此外,数值分类结果还表明,苦豆子根瘤菌与模式菌株的相似性较低,它们所形成的4个独立群可能有新种出现。     

Anthropology and genetics of the caucasus peoples and the problem of the origin of the caucasoids

The electrophoretical polymorphisms of some blood proteins were studied in the Talysh population of Pirasora situated in South-East Azerbaidjan. We calculated the gene frequencies of these polymorphisms and determined the genetic distances between the Talyshes and some Iranian populations of North, Central and South Iran, Afghans, and three populations of Azerbaijan. The Talyshes are very close to Iranians of Shiraz, whereas they are distant from the Azerbaijanians. Anthropological investigations showed that the Caucasoids and Mongoloids lived in the Aragvi Basin since the Eneolithic period. This was stated by Alexeev (1974), who emphasized the mixture of the Caucasus populations from ancient times on. We calculated the genetic distances between the Caucasus populations and numerous populations of other geographic regions, considering 28 alleles of 12 loci of blood group, serum protein and red cell enzyme polymorphisms and constructed the dendrogram of these populations. The position of the Caucasus populations in the dendrogram corresponds on principle to the earlier anthropological observations. The clustering of the Caucasoid populations corresponds completely with anthropological and historical data, and supports our earlier hypothesis (Nazarova 1999) concerning the differentiation of Caucasoids, Northern Mongoloids and Amerinds from the populations, which inhabitated Asia in palaeolithic times.     

人类基因组及后基因组研究进展及其应用与开发研究现状

人类对自身基因组的研究,随着人类基因组工作草图的绘制完成和对基因功能研究的深入已加快进入了实质性、关键性的开发利用阶段。本文概述了人类基因组及后基因组的研究进展及依此开展基因治疗及基因（组）药物研制等应用开发研究的现状。     

Serology and systematics of the Ebenales and the Theales

The systematic position ofthe Ebenaceae, Sapotaceae, Styracaceae, Ochnaceae, Stachyuraceae, Dipterocarpaceae, Clusiaceae and Hypericaceae has been investigated using serological comparisons of sets of antigenic determinants. The results show that the Sytracaceae and Sapotaceae are undoubtedly more closely associated with the Actinidiaeceae and Theaceae, respectively, than with each other. We found no corresponding determinants betnween antigen systems from the Ebenaceae and systems from any other family whose relations to this family have been proposed. As discovered previously, investigations of antigen systems from the Ochnaceae, Dipterocarpaceae, Stachyuraceae, Clusiaceae and Hypericaceae are against the idea of a natural order “Theales” in which these families, or at least some of them, are combined with the Theaceae and Actinidiaceae. This paper completes our previous investigations which largely support a superorder Ericanae sensu Ehrendorfer and Takhtajan. We propose to include the Actinidiaceae and Theaceae in this superorder, assigning them a central position laong with the Sapotaceae and Sytracaeae on one side and the Primulales and Ericales on the other. Another most interesting finding is that there are corresponding determinants between antigen systems from the members of the Ericanae and representatives of the Polemoniaceae and Loasaceae.     

Kinematics and dynamics of the temporomandibular joint and of the movements of the mandible

In order to analyze the complicated movements of the mandible as the open-closing movement and the protrusio are, it is useful to evaluate the basic kinematic principles and reduce them to simple technical constructions. Both the open-closing movement and the protrusio could be reduced to 4-bar links, which were used to simulate the movements with help of a computer. Besides, the polodes and the curves of points in the muscular attachments could be constructed. The 2 entirely different 4-bar links have 3 things in common: The resting system - cranium, the moving system - mandibula, and 1 of the 2 arms connecting these 2 systems - the ligamentum laterale. As this ligament is taut during movements it can be considered a "guiding ligament" representing 1 of the 3 determining components of the mandibular movements. The other of the 2 arms has no anatomical equivalent; this arm, however, is "replaced" by the 2 other determining components of the mandibular movements: the joint and the muscles. The curves, which the Caput mandibulae describes, are practically identical for the open-closing movement and the protrusio despite of the different 4-bar links and these curves exactly correspond to the Discus articularis, taut by the upper part of the M. pterygoideus lateralis. The muscles do not only just move the mandibula, but they are also the component, which can choose between the different mandibular movements. By means of the curves, which points in the muscular attachments describe, the function of the masticatory muscles could be analyzed exactly.     

On the structure and dynamics of the complex of the nucleosome and the linker histone

Several different models of the linker histone (LH)–nucleosome complex have been proposed, but none of them has unambiguously revealed the position and binding sites of the LH on the nucleosome. Using Brownian dynamics-based docking together with normal mode analysis of the nucleosome to account for the flexibility of two flanking 10 bp long linker DNAs (L-DNA), we identified binding modes of the H5-LH globular domain (GH5) to the nucleosome. For a wide range of nucleosomal conformations with the L-DNA ends less than 65 Å apart, one dominant binding mode was identified for GH5 and found to be consistent with fluorescence recovery after photobleaching (FRAP) experiments. GH5 binds asymmetrically with respect to the nucleosomal dyad axis, fitting between the nucleosomal DNA and one of the L-DNAs. For greater distances between L-DNA ends, docking of GH5 to the L-DNA that is more restrained and less open becomes favored. These results suggest a selection mechanism by which GH5 preferentially binds one of the L-DNAs and thereby affects DNA dynamics and accessibility and contributes to formation of a particular chromatin fiber structure. The two binding modes identified would, respectively, favor a tight zigzag chromatin structure or a loose solenoid chromatin fiber.     

Biophysics and Structure of the Patch and the Gigaseal

Interpreting channel behavior in patches requires an understanding of patch structure and dynamics, especially in studies of mechanosensitive channels. High resolution optical studies show that patch formation occurs via blebbing that disrupts normal membrane structure and redistributes in situ components including ion channels. There is a 1-2 μm region of the seal below the patch where proteins are excluded and this may consist of extracted lipids that form the gigaseal. Patch domes often have complex geometries with inhomogeneous stresses due to the membrane-glass adhesion energy (E_a), cytoskeletal forces, and possible lipid subdomains. The resting tension in the patch dome ranges from 1-4 mN/m, a significant fraction of the lytic tension of a bilayer (∼10 mN/m). Thus, all patch experiments are conducted under substantial, and uneven, resting tension that may alter the kinetics of many channels. E_a seems dominated by van der Waals attraction overlaid with a normally repulsive Coulombic force. High ionic strength pipette saline increased E_a and, surprisingly, increased cytoskeletal rigidity in cell-attached patches. Low pH pipette saline also increased E_a and reduced the seal selectivity for cations, presumably by neutralizing the membrane surface charge. The seal is a negatively charged, cation selective, space with a resistance of ∼7 gigohm/μm in 100 mM KCl, and the high resistivity of the space may result from the presence of high viscosity glycoproteins. Patches creep up the pipette over time with voltage independent and voltage dependent components. Voltage-independent creep is expected from the capillary attraction of E_a and the flow of fresh lipids from the cell. Voltage-dependent creep seems to arise from electroosmosis in the seal. Neutralization of negative charges on the seal membrane with low pH decreased the creep rate and reversed the direction of creep at positive pipette potentials.     

The biogeography of Nothofagus and Trigonobalanus and the origin of the Fagaceae

The suggestion that Trigonobalanus excelsa reached Colombia by migration from south-east Asia via the Bering land-bridge is criticized. The distribution of Trigonobalanus can be more simply explained by the disruption and drift of the former Pacific continent and the peninsula of West Gondwanaland. All but the New Guinea species of Nothofagus remain on the drifted fragments of the Gondwana peninsula, the original home of the family. Drift accounts for the present disjunct distribution of related Nothofagus species in the Southern hemisphere, but topoclines in characters of the fructifications and of the leaves linking New Zealand, New Caledonia and New Guinea indicate the overland migration route into the Pacific continent. Diversification of the family occurred in Pacifica before that continent was disrupted in the late Jurassic. With the formation of Eurasia, a topocline in leaf characters developed in Fagus along the migration route from China to Western Europe. Absence of topoclines involving the Bering land-bridge indicate that this bridge played no significant part in the dispersal of the Fagaceae. Shedding of the fruits of Glossopteris before the development of an embryo draws attention to the primitive character of delay in fertilization found in Nothofagus.