紫罗酮和麦角固醇对酵母生长及产辅酶Q10的影响

研究了β-紫罗酮和麦角固醇对酵母生长及产辅酶Q₁₀的影响。研究发现,β-紫罗酮能促进菌体积累辅酶Q₁₀,当培养基中β-紫罗酮的添加量为0.208×10^-3mol/L时,菌体中CoQ₁₀的含量提高了28.3%;少量麦角固醇能促进菌体产辅酶Q₁₀,当麦角固醇的添加量为0.15×10^-4mol/L时,菌体中CoQ₁₀的含量提高了31.8%,而增加麦角固醇的添加     

营养条件和流加发酵对放射型根瘤菌(Rhizobium radiobacter)产辅酶Q10的影响

利用放射型根瘤菌WSH2 6 0 1(RhizobiumradiobacterWSH2 6 0 1)重点考察了葡萄糖、蔗糖、玉米浆和蛋白胨、添加物以及流加发酵对细胞生长和产辅酶Q1 0 的影响 ,结果表明 ,葡萄糖和蔗糖适合于生产辅酶Q1 0 的最佳浓度分别为 30g L和 40g L ;辅酶Q1 0 发酵时玉米浆和蛋白胨的最适浓度分别为 11g L和 16g L ;添加蕃茄汁、玉米浆能提高发酵液的生物量 ,玉米浆、异戊醇、L 甲硫氨基酸等能促进辅酶Q1 0 的积累 ;与分批发酵相比 ,在 7L罐上流加蔗糖其细胞生物量 (DCW)和辅酶Q1 0 积累量增加 ,若在流加蔗糖的同时流加适当浓度的玉米浆能显著提高辅酶Q1 0 的产量 ,最大产量达到 5 2 .4mg L ;最大生物量 (DCW)和胞内辅酶Q1 0 含量 (C B值 )分别达到 2 6 .4g L和 2 .38mg g DCW ,比不流加的分批发酵分别提高 5 3 %和 33% ,比只流加蔗糖分别提高 2 4%和 2 6 %。     

代谢工程改造大肠杆菌生产辅酶Q10

辅酶Q10(CoQ10)是一种脂溶性抗氧化剂,具有提高人体免疫力、延缓衰老和增强人体活力等功能,广泛应用于制药行业和化妆品行业。微生物发酵法能可持续性生产辅酶Q10,具有越来越多的商业价值。本研究首先将来自类球红细菌的十聚异戊二烯焦磷酸合成酶基因(dps)整合到大肠杆菌ATCC 8739染色体上,敲除内源的八聚异戊二烯焦磷酸合成酶基因(ispB),使内源的辅酶Q8合成途径被辅酶Q10合成途径取代,得到稳定生产辅酶Q10的菌株GD-14,其辅酶Q10产量达0.68 mg/L,单位细胞含量达0.54 mg/g DCW。随后用多个固定强度调控元件在染色体上对MEP途径的关键基因dxs和idi基因以及ubiCA基因进行组合调控,将辅酶Q10单位细胞含量提高2.46倍(从0.54到1.87 mg/g)。进一步引入运动发酵单胞菌Zymomonas mobilis的Glf转运蛋白代替自身的磷酸烯醇式丙酮酸:碳水化合物磷酸转移酶系统(PTS),使辅酶Q10产量进一步提高16%。最后,对高产菌株GD-51进行分批补料发酵,辅酶Q10产量达433 mg/L,单位细胞含量达11.7 mg/g DCW。这是目前为止文献报道的大肠杆菌产辅酶Q10最高菌株。     

高硝化活性亚硝酸盐氧化细菌的培养和应用研究

针对本实验室筛选得到的一株亚硝酸盐氧化细菌(nitrite-oxidizingbacteria),研究了在28℃~30℃、摇床转速为110r/min时,pH、氮源、碳源、NaCl、有机物对菌体生长的影响。结果表明,培养基pH8·0~8·5、NaNO2含量4,500mg/L、Na2CO3含量1·5g/L、NaCl含量0~0·5%、葡萄糖含量0~0·1%时,亚硝酸盐氧化细菌生长良好,培养9d时,细菌浓度可达4·6×109MPN/mL,且培养基中的NO2--N能全部被硝化为NO3--N。培养基中NaCl含量大于0·5%、葡萄糖含量大于0·1%时,亚硝酸盐氧化细菌对氮源的利用受到抑制。亚硝酸盐氧化细菌降解淡水养殖池塘中的NO2--N试验表明,在水温25℃、pH8·6的池塘中,NO2--N从菌体投放后的第3d开始下降,18d后NO2--N由1·47mol/L下降至0·49mol/L。     

高硝性化活亚硝酸盐氧化细菌的培养和应用研究

针对本实验室筛选得到的一株亚硝酸盐氧化细菌(nitrite-oxidizingbacteria),研究了在28℃~30℃、摇床转速为110r/min时,pH、氮源、碳源、NaCl、有机物对菌体生长的影响。结果表明,培养基pH8·0~8·5、NaNO2含量4,500mg/L、Na2CO3含量1·5g/L、NaCl含量0~0·5%、葡萄糖含量0~0·1%时,亚硝酸盐氧化细菌生长良好,培养9d时,细菌浓度可达4·6×109MPN/mL,且培养基中的NO2--N能全部被硝化为NO3--N。培养基中NaCl含量大于0·5%、葡萄糖含量大于0·1%时,亚硝酸盐氧化细菌对氮源的利用受到抑制。亚硝酸盐氧化细菌降解淡水养殖池塘中的NO2--N试验表明,在水温25℃、pH8·6的池塘中,NO2--N从菌体投放后的第3d开始下降,18d后NO2--N由1·47mol/L下降至0·49mol/L。     

皂化法分离测定三孢布拉氏霉菌体中辅酶Q10的研究

目的:为研究醇碱皂化法分离三孢布拉氏霉菌体中辅酶Q10的最佳工艺。方法:采用正交实验,对醇碱皂化法分离测定三孢布拉氏霉菌体中辅酶Q10的各工艺条件进行了研究。结果:皂化时间、醇碱浓度及焦性没食子酸添加量对皂化效果影响显著,而温度(50~90℃)对其影响较小。醇碱皂化法提取三孢布拉氏霉中辅酶Q10的最佳工艺条件为:KOH加入量为湿菌体的1/2(w/w),醇碱浓度为10%,焦性没食子酸量添加量为湿菌体的10%(w/w),在70℃下皂化60min。此提取工艺平均回收率达81.8%,RSD为2.6%。     

利用指数流加补料高密度发酵产β-呋喃果糖苷酶重组大肠杆菌

【目的】对重组大肠杆菌BL21(DE3)/pET22b-β-ffase进行高密度发酵产β-呋喃果糖苷酶工艺研究。【方法】比较溶氧反馈补料和指数流加补料对重组菌发酵产酶的影响,对不同比生长速率和诱导时机进行优化。【结果】确定了双阶段指数流加过程中重组菌生长的比生长速率,分别控制诱导前期比生长速率为0.20 h~(-1),诱导后期比生长速率为0.13 h~(-1),诱导时机为指数中期。获得细胞干重约为51 g/L,最高酶活达到1.79×10~5 U/L,单位菌体产酶量为3 510 U/g,单位产酶速率达到3.58×10~4 U/(L·h),生物量、单位菌体产酶量和产酶速率分别是指数流加未优化前的1.8、1.7和3.0倍。【结论】双阶段指数流加补料工艺能有效提高β-呋喃果糖苷酶的产酶量,为β-呋喃果糖苷酶的进一步工业化奠定基础。     

营养条件和流加发酵对放射型根瘤菌（Rhizobium radiobacter）产辅酶Q10的影响

利用放射型根瘤菌WSH2601（Rhizobium radiobacter WSH2601）重点考察了葡萄糖、蔗糖、玉米浆和蛋白胨、添加物以及流加发酵对细胞生长和产辅酶Q₁₀的影响,结果表明, 葡萄糖和蔗糖适合于生产辅酶Q₁₀的最佳浓度分别为30 g/L和40 g/L;辅酶Q₁₀发酵时玉米浆和蛋白胨的最适浓度分别为11g/L和16g/L;添加蕃茄汁、玉米浆能提高发酵液的生物量,玉米浆、异戊醇、L-甲硫氨基酸等能促进辅酶Q₁₀的积累;与分批发酵相比,在7L罐上流加蔗糖其细胞生物量（DCW）和辅酶Q₁₀积累量增加,若在流加蔗糖的同时流加适当浓度的玉米浆能显著提高辅酶Q₁₀的产量,最大产量达到52.4 mg/L;最大生物量（DCW）和胞内辅酶Q₁₀含量（C/B值）分别达到26.4 g/L和2.38 mg/g-DCW,比不流加的分批发酵分别提高53%和33%,比只流加蔗糖分别提高24%和26%。     

类球红细菌添加前体物产辅酶Q_(10)的工艺优化

目的:考察摇瓶与发酵罐水平下类球红细菌CU20-9产辅酶Q10添加前体物质的最优配比。方法:通过正交试验优化发酵前体配比,考察摇瓶发酵多种前体物质的添加对辅酶Q10产量的影响,并利用发酵罐进行中试规模实验。结果:优化后发酵前体配比为维生素B1 10 mg/L、乙酸钠100 mg/L、对羟基苯甲酸20 mg/L、花生油0.01%。结论:前体添加及优化配比后,摇瓶及中试发酵水平下辅酶Q10的产量均有显著提高。     

生物表面活性剂对红球菌SY095降解正十六烷及细胞表面性质的影响

目的:研究红球菌SY095产生物表面活性剂对正十六烷的溶解性、微生物降解正十六烷的效率、菌体生长及菌体表面疏水性的影响。方法:测定添加不同生物表面活性剂的降解体系中菌体生物量、细胞表面疏水性、正十六烷含量的变化。结果:生物表面活性剂对疏水性底物正十六烷具有很强的增溶作用,可以显著提高正十六烷的表观溶解度;生物表面活性剂对正十六烷的生物降解具有促进作用,添加量为100 mg/L时,96 h正十六烷去除率达93.32%;生物表面活性剂能明显促进红球菌SY095生长,添加量为300 mg/L时,菌株32 h生物量为未添加生物表面活性剂对照组的2.7倍;生物表面活性剂还能引起红球菌SY095菌体表面疏水性明显增大,添加量为25 mg/L时,菌株对数生长期BATH值达66.94%,高于未添加生物表面活性剂对照组的42.99%。结论:生物表面活性剂可以增加菌体的表面疏水性,促进微生物对正十六烷的生物降解。     

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.     

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.     

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.     

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.     

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.     

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。     

Comparison of the Effects of Flexion and Extension of the Thumb and Fingers on the Position and Cross-Sectional Area of the Median Nerve

Objective

To assess the separate effects of thumb and finger extension/flexion on median nerve position and cross-sectional area.

Methods

Ultrasonography was used to assess median nerve transverse position and cross-sectional area within the carpal tunnel at rest and its movement during volitional flexion of the individual digits of the hand. Both wrists of 165 normal subjects (11 men, 4 women, mean age, 28.6, range, 22 to 38) were studied.

Results

Thumb flexion resulted in transverse movement of the median nerve in radial direction (1.2±0.6 mm), whereas flexion of the fingers produced transverse movement in ulnar direction, which was most pronounced during flexion of the index and middle fingers (3.2±0.9 and 3.1±1.0 mm, respectively). Lesser but still statistically significant movements were noted with flexion of the ring finger (2.0±0.8 mm) and little finger (1.2±0.5 mm). Flexion of the thumb or individual fingers did not change median nerve cross-sectional area (8.5±1.1 mm²).

Conclusions

Volitional flexion of the thumb and individual fingers, particularly the index and middle fingers, produced significant transverse movement of the median nerve within the carpal tunnel but did not alter the cross-sectional area of the nerve. The importance of these findings on the understanding of the pathogenesis of the carpal tunnel syndrome and its treatment remains to be investigated.     

On the Microanatomy of the Brain and the Innervation and Homologues of the Cephalic Appendages of Hesionidae and Syllidae (Polychaeta)

Abstract Earlier papers dealing with the anatomy of the hesionids and syllids were studied. Thereby it was found that information about the structure of the central nervous system was meagre. As a result, the anterior end appendages, especially the large, laterloventral ones of the Syllidae, have been differently interpreted. This prompted a re-investigation. The circum-oesophageal connectives, the brain commissures and the innervation of the alimentary canal and the cephalic appendages of a number of hesionid and syllid species were studied. The results, summarized in schematic diagrams, were compared with corresponding observations in other polychaete families. Among other things, it was concluded that not only the latero-ventral cephalic appendages of the hesionids but also those of the syllids are homologous with the palps of the nereids and of many other “errant” and “sedentary” families.