Special proton-gradient-transfer acid complexes （PGTACs） in which the bonded protons are not equivalent and have gradients in transfer ability, acidity, and reactivity were reported. The acidity gradient of the prot...Special proton-gradient-transfer acid complexes （PGTACs） in which the bonded protons are not equivalent and have gradients in transfer ability, acidity, and reactivity were reported. The acidity gradient of the protons gave the PGTACs excellent catalytic activity and selectivity in the esterifica- tion of terpenols. These PGTACs are ＂reaction-induced self-separation catalysts＂ and can be easily reused. The kinetics with PGTACs as catalyst in the esterification of geraniol were also studied for use in engineering design.展开更多
A group of coenocytic marine algae differs from higher plants,whose totipotency depends on an intact cell(or protoplast).Instead,this alga is able to aggregate its extruded protoplasm in sea water and generate new mat...A group of coenocytic marine algae differs from higher plants,whose totipotency depends on an intact cell(or protoplast).Instead,this alga is able to aggregate its extruded protoplasm in sea water and generate new mature individuals.It is thought that lectins play a key role in the aggregation process.We purified a lectin associated with the aggregation of cell organelles in Bryopsis hypnoides.The lectin was ca.27 kDa with a pI between pH 5 and pH 6.The absence of carbohydrate suggested that the lectin was not a glycoprotein.The hemagglutinating activity(HA) of the lectin was not dependent on the presence of divalent cations and was inhibited by N-Acetylgalactosamine,N-Acetylglucosamine,and the glycoprotein bovine submaxillary mucin.The lectin preferentially agglutinated Gram-negative bacterium.The HA of this lectin was stable between pH 4 to pH 10.Cell organelles outside the cytoplasm were agglutinated by the addition of lectin solution(0.5 mg ml-1).Our results suggest that the regeneration of B.hypnoides is mediated by this lectin.We also demonstrated that the formation of cell organelle aggregates was inhibited by nigericin in natural seawater(pH 8.0).Given that nigericin dissipates proton gradients across the membrane,we hypothesize that the aggregation of cell organelles was proton-gradient dependent.展开更多
Ion channels are membrane proteins that are found in a number of viruses and which are of crucial physiological importance in the viral life cycle. They have one common feature in that their action mode involves a cha...Ion channels are membrane proteins that are found in a number of viruses and which are of crucial physiological importance in the viral life cycle. They have one common feature in that their action mode involves a change of electrochemical or proton gradient across the bilayer lipid membrane which modulates viral or cellular activity. We will discuss a group of viral channel proteins that belong to the viroproin family, and which participate in a number of viral functions including promoting the release of viral particles from cells. Blocking these channel-forming proteins may be ＂lethal＂, which can be a suitable and potential therapeutic strategy. In this review we discuss seven ion channels of viruses which can lead serious infections in human beings： M2 of influenza A, NB and BM2 of influenza B, CM2 of influenza C, Vpu of HIV-1, p7 of HCV and 2B of picomaviruses.展开更多
This paper describes theoretical steps to develop an optical nanobiosensor using bacteriorhodopsin （BR） as the biomembrane and Single-Walled Carbon NanoTube （SWCNT） as the scaffold. Bacteriorhodopsin is a retinal ...This paper describes theoretical steps to develop an optical nanobiosensor using bacteriorhodopsin （BR） as the biomembrane and Single-Walled Carbon NanoTube （SWCNT） as the scaffold. Bacteriorhodopsin is a retinal protein used by archaea that come under the family of halobacteria. This retinal protein acts as a proton pump and resulting proton gradient is used to change the voltage that pass across the drain and source. The biosensor contains nano ISFET where the channel is made of a carbon nanotube for the conduction of current. The gate is replaced by bacteriorhodopsin biomembrane. Bacteriorhodopsin can be used as a molecular-level ultra fast bi-stable red / green photo switch for making 3D optical molecular memories that reliably store data with 10,000 molecules/bit. The molecules switch in femtoseconds. Biomembrane will sense 510 nm and 650 nm wavelength of light and the sensing voltage can be used to convert the data into digital signals. This molecular level memory device can be used for ‘Read-Write＇ operations. The sensor performance will also be ultra fast since it uses photons for the data storage, which are much faster than electrons used in normal memory devices, and the 3D storage capacity is much higher maximum of 10^13/cm^2.展开更多
The purpose of this study was to explore the change of telomerase in passage from human endometrial stromal stem cells isolated from human endometrium.Telomerase activity of cultured endometrial stromal cells was asse...The purpose of this study was to explore the change of telomerase in passage from human endometrial stromal stem cells isolated from human endometrium.Telomerase activity of cultured endometrial stromal cells was assessed at mRNA and protein levels using RT-PCR and immunohistochemistry technique.Telomerase mRNA and protein levels were higher at early passages,and then had a gradually decreased trend of immunoreactive intensity and gradually weakened positive cells with progressive passage in endometrial stromal stem cells.These results suggest that telomerase is contributed to the insenecence of endometrial stem cell.展开更多
The partially coherent beams propagating through random media have been used in the past to enhance effect of nonlinear optical interaction. Moreover, after propagation through a random （or turbulent） medium the coh...The partially coherent beams propagating through random media have been used in the past to enhance effect of nonlinear optical interaction. Moreover, after propagation through a random （or turbulent） medium the coherent beam becomes a partially coherent one. In this research, the analytical formula for the average intensity of Gaussian beam propagating through random medium is derived and the influence of coherent partiality on optical gradient force acting on dielectric particle rounded by a random media is investigated.展开更多
Phycobilisomes (PBSs) are the main accessory light-harvesting complexes in cyanobacteria and their movement between photosystems (PSs) affects cyclic and respiratory electron transport.However,it remains unclear wheth...Phycobilisomes (PBSs) are the main accessory light-harvesting complexes in cyanobacteria and their movement between photosystems (PSs) affects cyclic and respiratory electron transport.However,it remains unclear whether the movement of PBSs between PSs also affects the transthylakoid proton gradient (ΔpH).We investigated the effect of PBS movement on ΔpH levels in a unicellular cyanobacterium Synechocystis sp.strain PCC 6803,using glycinebetaine to immobilize and couple PBSs to photosystem II (PSII) or photosystem I (PSI) by applying under far-red or green light,respectively.The immobilization of PBSs at PSII inhibited decreases in ΔpH,as reflected by the slow phase of millisecond-delayed light emission (ms-DLE) that occurs during the movement of PBSs from PSII to PSI.By contrast,the immobilization of PBSs at PSI inhibited the increase in ΔpH that occurs when PBSs move from PSI to PSII.Comparison of the changes in ΔpH and electron transport caused by the movement of PBSs between PSs indicated that the changes in ΔpH were most likely caused by respiratory electron transport.This will further improve our understanding of the physiological role of PBS movement in cyanobacteria.展开更多
线粒体是有氧呼吸的主要场所,也是细胞的“能量工厂”.线粒体内膜上的电子传递链在传递电子时释放的能量会转换为跨膜质子梯度,该质子梯度随后被三磷酸腺苷合成酶利用并生成三磷酸腺苷(adenosine triphosphate,ATP)^([1]).线粒体内膜对...线粒体是有氧呼吸的主要场所,也是细胞的“能量工厂”.线粒体内膜上的电子传递链在传递电子时释放的能量会转换为跨膜质子梯度,该质子梯度随后被三磷酸腺苷合成酶利用并生成三磷酸腺苷(adenosine triphosphate,ATP)^([1]).线粒体内膜对于质子的低通透性使电子传递过程与ATP生成紧密偶联.解偶联蛋白1(uncoupling protein 1,UCP1)是棕色脂肪组织中高表达的线粒体内膜转运蛋白,能够使质子绕过ATP合成酶而直接到达线粒体基质,从而将质子梯度转化为热能释放.展开更多
基金supported by the National Natural Science Foundation of China (21376115, 21576129)~~
文摘Special proton-gradient-transfer acid complexes （PGTACs） in which the bonded protons are not equivalent and have gradients in transfer ability, acidity, and reactivity were reported. The acidity gradient of the protons gave the PGTACs excellent catalytic activity and selectivity in the esterifica- tion of terpenols. These PGTACs are ＂reaction-induced self-separation catalysts＂ and can be easily reused. The kinetics with PGTACs as catalyst in the esterification of geraniol were also studied for use in engineering design.
基金Supported by the Natural Science Foundation of China (Nos 40806063,30830015)the National High Technology Research and Development Program of China (863 Program) (Nos2007AA09Z406,2006AA10A413)
文摘A group of coenocytic marine algae differs from higher plants,whose totipotency depends on an intact cell(or protoplast).Instead,this alga is able to aggregate its extruded protoplasm in sea water and generate new mature individuals.It is thought that lectins play a key role in the aggregation process.We purified a lectin associated with the aggregation of cell organelles in Bryopsis hypnoides.The lectin was ca.27 kDa with a pI between pH 5 and pH 6.The absence of carbohydrate suggested that the lectin was not a glycoprotein.The hemagglutinating activity(HA) of the lectin was not dependent on the presence of divalent cations and was inhibited by N-Acetylgalactosamine,N-Acetylglucosamine,and the glycoprotein bovine submaxillary mucin.The lectin preferentially agglutinated Gram-negative bacterium.The HA of this lectin was stable between pH 4 to pH 10.Cell organelles outside the cytoplasm were agglutinated by the addition of lectin solution(0.5 mg ml-1).Our results suggest that the regeneration of B.hypnoides is mediated by this lectin.We also demonstrated that the formation of cell organelle aggregates was inhibited by nigericin in natural seawater(pH 8.0).Given that nigericin dissipates proton gradients across the membrane,we hypothesize that the aggregation of cell organelles was proton-gradient dependent.
文摘Ion channels are membrane proteins that are found in a number of viruses and which are of crucial physiological importance in the viral life cycle. They have one common feature in that their action mode involves a change of electrochemical or proton gradient across the bilayer lipid membrane which modulates viral or cellular activity. We will discuss a group of viral channel proteins that belong to the viroproin family, and which participate in a number of viral functions including promoting the release of viral particles from cells. Blocking these channel-forming proteins may be ＂lethal＂, which can be a suitable and potential therapeutic strategy. In this review we discuss seven ion channels of viruses which can lead serious infections in human beings： M2 of influenza A, NB and BM2 of influenza B, CM2 of influenza C, Vpu of HIV-1, p7 of HCV and 2B of picomaviruses.
文摘This paper describes theoretical steps to develop an optical nanobiosensor using bacteriorhodopsin （BR） as the biomembrane and Single-Walled Carbon NanoTube （SWCNT） as the scaffold. Bacteriorhodopsin is a retinal protein used by archaea that come under the family of halobacteria. This retinal protein acts as a proton pump and resulting proton gradient is used to change the voltage that pass across the drain and source. The biosensor contains nano ISFET where the channel is made of a carbon nanotube for the conduction of current. The gate is replaced by bacteriorhodopsin biomembrane. Bacteriorhodopsin can be used as a molecular-level ultra fast bi-stable red / green photo switch for making 3D optical molecular memories that reliably store data with 10,000 molecules/bit. The molecules switch in femtoseconds. Biomembrane will sense 510 nm and 650 nm wavelength of light and the sensing voltage can be used to convert the data into digital signals. This molecular level memory device can be used for ‘Read-Write＇ operations. The sensor performance will also be ultra fast since it uses photons for the data storage, which are much faster than electrons used in normal memory devices, and the 3D storage capacity is much higher maximum of 10^13/cm^2.
基金Supported by the National Natural Science Foundation of China(30801238)
文摘The purpose of this study was to explore the change of telomerase in passage from human endometrial stromal stem cells isolated from human endometrium.Telomerase activity of cultured endometrial stromal cells was assessed at mRNA and protein levels using RT-PCR and immunohistochemistry technique.Telomerase mRNA and protein levels were higher at early passages,and then had a gradually decreased trend of immunoreactive intensity and gradually weakened positive cells with progressive passage in endometrial stromal stem cells.These results suggest that telomerase is contributed to the insenecence of endometrial stem cell.
文摘The partially coherent beams propagating through random media have been used in the past to enhance effect of nonlinear optical interaction. Moreover, after propagation through a random （or turbulent） medium the coherent beam becomes a partially coherent one. In this research, the analytical formula for the average intensity of Gaussian beam propagating through random medium is derived and the influence of coherent partiality on optical gradient force acting on dielectric particle rounded by a random media is investigated.
基金supported by the National Natural Science Foundation of China (30770175)the National Basic Research Program of China (2009CB118500)+2 种基金the Key Project of the Chinese Ministry of Education (209045)the Shanghai Leading Academic Discipline Project (S30406)the Leading Academic Discipline Project of Shanghai Normal University (DZL808)
文摘Phycobilisomes (PBSs) are the main accessory light-harvesting complexes in cyanobacteria and their movement between photosystems (PSs) affects cyclic and respiratory electron transport.However,it remains unclear whether the movement of PBSs between PSs also affects the transthylakoid proton gradient (ΔpH).We investigated the effect of PBS movement on ΔpH levels in a unicellular cyanobacterium Synechocystis sp.strain PCC 6803,using glycinebetaine to immobilize and couple PBSs to photosystem II (PSII) or photosystem I (PSI) by applying under far-red or green light,respectively.The immobilization of PBSs at PSII inhibited decreases in ΔpH,as reflected by the slow phase of millisecond-delayed light emission (ms-DLE) that occurs during the movement of PBSs from PSII to PSI.By contrast,the immobilization of PBSs at PSI inhibited the increase in ΔpH that occurs when PBSs move from PSI to PSII.Comparison of the changes in ΔpH and electron transport caused by the movement of PBSs between PSs indicated that the changes in ΔpH were most likely caused by respiratory electron transport.This will further improve our understanding of the physiological role of PBS movement in cyanobacteria.
文摘线粒体是有氧呼吸的主要场所,也是细胞的“能量工厂”.线粒体内膜上的电子传递链在传递电子时释放的能量会转换为跨膜质子梯度,该质子梯度随后被三磷酸腺苷合成酶利用并生成三磷酸腺苷(adenosine triphosphate,ATP)^([1]).线粒体内膜对于质子的低通透性使电子传递过程与ATP生成紧密偶联.解偶联蛋白1(uncoupling protein 1,UCP1)是棕色脂肪组织中高表达的线粒体内膜转运蛋白,能够使质子绕过ATP合成酶而直接到达线粒体基质,从而将质子梯度转化为热能释放.
