钝顶螺旋藻（Spirulina platensis）藻胆体Langmuir-Blodgett膜

从钝顶螺旋藻中分离制备完整藻胆体 ,然后滴加于空气 水界面上 ,应用LB膜技术制备藻胆体LB膜。结果表明 ,藻胆体在空气 水界面上具有很好的成膜性能。将藻胆体LB单层膜转移到刚揭开的云母表面 ,喷一层金 ,然后用扫描隧道显微镜观察。结果表明 ,藻胆体在Langmuir Blodgett膜中的排列方式与其在体内类囊体膜表面的排列方式类似 ,一排排聚集在一起 ,然后排列成膜。藻胆体的“核”吸附在云母表面 ,而藻胆体的“杆”伸向外面。由于钝顶螺旋藻易于规模化培养 ,藻胆体容易批量制备 ,加之藻胆体具有的独特的光物理、光化学特性和良好的成膜性能 ,以及本身就是纳米量级的颗粒 (5 0 70nm) ,预示着藻胆体在纳米光电子器件中具有很好的应用前景。     

螺旋藻的培养及对某些生化特性的研究

很多学者对钝顶螺旋藻(Spiru lina platensis)进行了培养和有关生理生化的研究。发现它在热带高碱性湖泊中具有很高的生长优势。Orio报道这种藻的蛋白质     

螺旋藻（Spirulina platensis）藻胆体在解离过程中荧光发射光谱和光能传递的研究

对螺旋藻（Ｓｐｉｒｕｌｉｎａｐｌａｔｅｎｓｉｓ）藻胆体在室温和７７Ｋ处于不同浓度磷缓冲溶液和不同解离时间的荧光发射光谱进行了研究。藻胆体在０．９ｍｏｌ／Ｌ磷酸缓冲溶液中,由于没有发生解离,光能传递效率高,在７７Ｋ荧光发射光谱中只有一个峰,位于６８７ｎｍ,属于别藻蓝蛋白－Ｂ。当藻胆体悬浮在０．３ｍｏｌ／Ｌ磷酸缓冲溶液中１分钟,７７Ｋ荧光光谱的主峰出现在６８４ｎｍ．又出现６５５ｎｍ和６６６ｎｍ荧光峰,它们依次属子Ｃ－藻蓝蛋白和别藻蓝蛋白。在２小时;６５５ｎｍ荧先峰成为主峰,６８４ｎｍ荧光峰为次峰,６６６ｎｍ荧光肩消失。这表明Ｃ－藻蓝蛋白所捕获的先能已不能传递给别藻蓝蛋白,但能传给别藻蓝蛋白－Ｂ。我们提出在螺旋藻藻胆体中存在两类Ｃ－藻蓝蛋白,一是与别藻蓝蛋白相连接,另一是与别藻蓝蛋白－Ｂ相连接。     

螺旋藻（Spirulina platensis）藻胆体在解离过程中荧光发射光谱和光能传递的研究

对螺旋藻（Ｓｐｉｒｕｌｉｎａｐｌａｔｅｎｓｉｓ）藻胆体在室温和７７Ｋ处于不同浓度磷缓冲溶液和不同解离时间的荧光发射光谱进行了研究。藻胆体在０．９ｍｏｌ／Ｌ磷酸缓冲溶液中,由于没有发生解离,光能传递效率高,在７７Ｋ荧光发射光谱中只有一个峰,位于６８７ｎｍ,属于别藻蓝蛋白－Ｂ。当藻胆体悬浮在０．３ｍｏｌ／Ｌ磷酸缓冲溶液中１分钟,７７Ｋ荧光光谱的主峰出现在６８４ｎｍ．又出现６５５ｎｍ和６６６ｎｍ荧光峰,它们依次属子Ｃ－藻蓝蛋白和别藻蓝蛋白。在２小时;６５５ｎｍ荧先峰成为主峰,６８４ｎｍ荧光峰为次峰,６６６ｎｍ荧光肩消失。这表明Ｃ－藻蓝蛋白所捕获的先能已不能传递给别藻蓝蛋白,但能传给别藻蓝蛋白－Ｂ。我们提出在螺旋藻藻胆体中存在两类Ｃ－藻蓝蛋白,一是与别藻蓝蛋白相连接,另一是与别藻蓝蛋白－Ｂ相连接。     

鄂尔多斯螺旋藻（Spirulina erdosensis）光合生理的研究

对鄂尔多斯高原碱湖的鄂尔多斯螺旋藻Spirulinaerdosensis光合色素的吸收光谱、含量、光合速率和呼吸速率日变化进行了研究.结果表明:活体吸收光谱体现出了各色素在不同波段范围内的吸收差异;各种色素相对荧光强度有明显的差异.藻胆素的含量最高为97.86mg·g-1DW;类胡萝卜素的最低,为2.11mg·g-1DW;Chla为7.70mg·g-1DW.其光合速率的日变化呈单峰曲线,真、净光合速率均在13∶00达到最大,分别为36.24μmol·m-2·s-1和23.45μmol·m-2·s-1.     

螺藻旋Spirulina platensis整体细胞放氢特性的研究

螺旋藻Spirulina platensis具有氢酶。由氢酶催化的放H_2活性受到培养基中硝酸盐的抑制。这是由于氢酶与硝酸还原酶之间存在还原能力的竞争。以脲素取代硝酸盐可以部分地解除其抑制作用。放H_2活性随着暗中时间的延长而成倍加强。在氮气或氩气中比在空气中的放氢活性分别高出244％和287％。氧气抑制放H_2活性,约5％O_2达到半抑制浓度。CO对,放H_2的半抑制浓度为2％。当光照强度大于2000lx时完全抑制放H_2活性。光合放氧与放氢的矛盾可以通过光、暗交替处理,由暗中的耗氧呼吸以加协调。     

钝顶螺旋藻(Spirulina platensis)光系统Ⅰ的分离表征及稳定性

采用蔗糖密度梯度离心法对钝顶螺旋藻光合膜蛋白(PSI)进行分离纯化,并对其光谱学性质、热稳定性及光合放氧活性进行分析表征。结果发现,采用蔗糖密度精度离心法,可以成功分离出4条色素蛋白质复合体条带,其中最下层条带为完整的PSI三聚体,其每毫克叶绿素a光合放氧活性达到420μmol/h。当温度达到50℃左右时,分离得到的PSI在溶液开始变性失活。     

钝顶螺旋藻SP1(Spirulina platensis)对集约化养殖尾水氮磷的去除效果

针对集约化养殖模式后期硝酸盐氮和磷酸盐浓度较高的问题,实验设置生物絮团养殖尾水(BFW)和BG11培养液(BGW)两种水体环境,并以池塘常见优势微藻——绿色颤藻OC1(Oscillatoria chlorina)作为对比,研究分析了钝顶螺旋藻SP1(Spirulina platensis)对集约化养殖尾水氮磷的去除效果...     

小麦老化叶片蛋白水解酶的某些生化特性的研究（简报）

小麦叶片蛋白水解酶最适pH为5．0左右;最适温度：扬麦五号品种为50℃,野生一粒为45℃。碘乙酸、苯甲基磺酰氟明显抑制蛋白水解酶活力,前者大于后者;而半胱氨酸明显激活其活性。对小麦老化叶片起主要作用的是巯基类蛋白水解酶,丝氨酸蛋白酶也起一定作用。     

盐泽螺旋藻(Spirulina subsalsa)藻胆体的分离和特性

采用一种简便而快速的方法分离了盐泽螺旋藻的藻胆体。藻胆体的最大吸收波长位于618 nm,室温下荧光反射峰位于677～678 nm。利用7～15％SDS—聚丙烯酸胺梯度凝胶板状电泳,可分出三条有色多肽,其中藻蓝蛋白的α亚单位与别藻蓝蛋白的α亚单位几乎重叠,不易区分;另有分子量为117,99,53,49,27,24.5和14kD的七条无色多肽。117和 99kD多肽可能联结藻胆体和类囊体,并作为末端能量受体,而14kD多肽多为“核”亚结构的组分,其余的可能为“棒”亚结构内和“核”“棒”亚结构间的联结蛋白。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Synthesis and antimicrobial studies of hydrazone derivatives of 4-[3-(2,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid and 4-[3-(3,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid

Microbial resistance to antibiotics is an unresolved global concern, which needs urgent and coordinated action. One of the guidelines of the Centers for Disease Control and Preventions (CDC) to combat antibiotic resistance is the development of new antibiotics to treat drug-resistant bacteria. In our effort to find new antibiotics, we report the synthesis and antimicrobial studies of 30 new pyrazole derivatives. These novel molecules have been synthesized by using readily available starting materials and benign reaction conditions. Some of these molecules have shown activity with MIC values as low as 0.78?µg/mL against four bacterial strains; Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Acinetobacter baumannii. Furthermore, active molecules are non-toxic to mammalian cell line.

     

Novel compounds with potent CDK9 inhibitory activity for the treatment of myeloma

Cyclin-dependent kinases (CDKs) and Polo-like kinases (PLKs) play key role in the regulation of the cell cycle. The aim of our study was originally the further development of our recently discovered polo-like kinase 1 (PLK1) inhibitors. A series of new 2,4-disubstituted pyrimidine derivatives were synthesized around the original hit, but their PLK1 inhibitory activity was very poor. However the novel compounds showed nanomolar CDK9 inhibitory activity and very good antiproliferative effect on multiple myeloma cell lines (RPMI-8226).