Influence of high light stress on the photosynthesis of flag leaves of indica subspecies (cv. “Shanyou 63', sensitive to photoinhibition) and japonica subspecies (cv. “Wuyujing', resistant to photoin...Influence of high light stress on the photosynthesis of flag leaves of indica subspecies (cv. “Shanyou 63', sensitive to photoinhibition) and japonica subspecies (cv. “Wuyujing', resistant to photoinhibition) of rice ( Oryza sativa L.) was comparatively investigated. In both cultivars of rice, the excitation energy distribution between two photosystems was altered and the excitation energy transfer from light harvesting chlorophyll protein complexes to PSⅡ was inhibited by high light stress. These decreases were more pronounced in indica rice cultivar as compared to japonica one. The analysis of mild SDS_PAGE showed that in indica rice, high light stress almost disaggregated the trimer of light harvesting chlorophyll protein complexes of PSⅡ (LHC Ⅱ 1). The stress reduced the contents of internal antennae chlorophyll protein complexes of PSⅡ (CPa), light harvesting chlorophyll protein of PSⅠ (CPⅠa) and Chl a protein complex of PSⅠ reaction center (CPⅠ) as well as dimer of LHCⅡ (LHCⅡ 2) in indica rice. In japonica subspecies, however, high light stress depressed the contents of LHCⅡ 1, CPa and CPⅠa, but slightly impacted on CPⅠ content. Moreover, the increase in the contents of monomer of LHCⅡ by high light stress was found in both subspecies. In consistent with above results, analysis of polypeptide indicated that the amounts of 27 kD and 25 kD polypeptide of LHCⅡ in particular, as well as that of 21 kD polypeptide of CPⅠa were reduced by high light stress in both subspecies. It was found that, comparing with japonica rice, the stress pronouncedly diminished 43 kD and 47 kD proteins of CPa and 23 kD extrisic protein in indica rice.展开更多
[Objective] The paper was to precisely predict nutrient requirements and optimize ration formula, and explore the inherent feature of ration optimization of dairy cow. [Method] Based on cornell net carbohydrate and pr...[Objective] The paper was to precisely predict nutrient requirements and optimize ration formula, and explore the inherent feature of ration optimization of dairy cow. [Method] Based on cornell net carbohydrate and protein system (CNCPS) with integrating dynamic prediction models on main nutrient requirements of dairy cattle recommended by NRC (2001) and the CNCPS parameter database accumu- lated by Chinese feed database, the ration nutrient requirement dynamic calculation and total mixed ration (TMR) formula optimizing system for Holstein dairy cow was developed using FOXPRO database system and parametric linear programming algo- rithm. [Result] By optimizing a specific cow ration and analyzing its completed nutri- ents, the results showed that this system could entirely consider a lots of nutrient balances, such as concentrate fraction and forage fraction balance, rumen degrad- able protein and rumen undergradable protein balance, crude protein and lactation net energy balance, fibrous substances (ADF, NDF) and non-fiber carbohydrates (NFC) balance, calcium and phosphate balance, electrolytes balance and trace ele- ment balance etc., and could also calculate intestinal amino acid flow in terms of different models. [Conclusion] By using dynamic mathematical equations and comput- erized program, it can be realized for the ration formula design of lactating cow with all-round interoperable but mutual-constraining each other among ration nutrients.展开更多
Objective To deduce all potential ligands undiscovered experimentally by searching all the proteins containing same C-termini, which can bind a certain PDZ domain. Methods We developed a JAVA program for searching sho...Objective To deduce all potential ligands undiscovered experimentally by searching all the proteins containing same C-termini, which can bind a certain PDZ domain. Methods We developed a JAVA program for searching short exact sequence matches at C-terminus. According to the known C-termini, which PDZ domains recognized experimentally, Swissprot database has been searched by this program for all potential ligands. Results Some PDZ domains may have more potential ligand proteins, which are undiscovered yet experimentally. These bioinformatic results also provide clues for studying functions of hypothetical proteins and PDZ domains’ protein interactions in many different organisms. Conclusion The results may provide useful clues for discovering potential functions of hypothetical proteins and new functions of known proteins.展开更多
Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors known to play a pivotal role in regulations of metabolism. In order to yield soluble ligand binding domain of PPARδ (P...Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors known to play a pivotal role in regulations of metabolism. In order to yield soluble ligand binding domain of PPARδ (PPARδLBD) for screening ligands, the cDNA was amplified using total RNA from HepG2 cells by RT-PCR. Then the enzyme-digested product was inserted . downstream of the malE gene in the vectorpMAL-p2x, which encoded maltose-binding protein (MBP), resulting in the expression of an MBP-PPARδLBD fusion protein. The recombinant plasmid was transformed into E. coli TBI that was cultured shakily at 30 ℃, 200 r/min and induced by 0.4 mmol/L IPTG for 6 h. The cells were harvested by centrifugation and broken by sonication. The expressed fusion protein was soluble and accounted for 0.31 of the total protein in the supernatant. Western blot analysis showed that the expressed MBP-PPARδLBD could bind to anti-MBP-antibody. The MBP-PPARδLBD fusion protein of 77 kDa and the PPARδLBD protein of 34 kDa were obtained by amylose-resin affinity chromatography without or with digestion of Factor Xa. They were both homogeneity, judged by SDS-PAGE. The recombinant MBP-PPARδLBD and PPARδLBD protein with high purity is obtained, which provides the necessary material for screening and researching PPARδ ligands.展开更多
Most protein-ligand interactions take place on surfaces and include but not limited to factors such as chemical composition, hydrophobicity, electronegavitiy and shape complementarity. Past studies showed that protein...Most protein-ligand interactions take place on surfaces and include but not limited to factors such as chemical composition, hydrophobicity, electronegavitiy and shape complementarity. Past studies showed that protein-protein interactions occur on comparatively fiat regions whereas protein-ligand bindings involve crevices. In the search for such sites various approaches have been designed and developed each of which is algorithmically unique. The use of grid units or voxels has been demonstrated in early studies with relatively good results obtained. We present here an approximated approach comprising of the use of voxels and computer vision methods in the search for ligand-binding areas. Each test protein is modelled and analysed in 2D with all corresponding residues graphically presented for successfully identified sites. The study was carried out on 2 sets of proteins: FK506-bound proteins and heme-bound proteins with promising results obtained for all test cases.展开更多
The interactions between the new organometallic complexes, ferrocenesubstituted dithioocarborane conjugates (denoted as FcSB1, FcSB2 and FcSBCO) and hemoglobin (Hb) are investigated by electrochemistry, fluorescen...The interactions between the new organometallic complexes, ferrocenesubstituted dithioocarborane conjugates (denoted as FcSB1, FcSB2 and FcSBCO) and hemoglobin (Hb) are investigated by electrochemistry, fluorescence and UVvis absorption spectroscopy. The results demonstrate that FcSB1, FcSB2 and FcSBCO can bind to the heme iron center through the replacement of the weakly bound H20/02 in the distal heme pocket of Hb by their sulfur donor atoms, inducing the allosteric change from the R state (oxygenated conformation, relax) to T state (deoxygenated conformation, tense). The binding affinity is in the order of FcSBCO〉FeSB2〉FeSB1. Moreover, the fluorescence study illustrates that the three ferrocenecarborane conjugates differently affect the quarterly and tertiary structures as well as the polarity in the surrounding of the Trp and Tyr residues in Hb. Typically, FcSB2 mainly induces alterations of the microenvironment around the 1337Trp residue which is located on the cql32 interface of Hb. Such distinct influences are attributed to the structural features of FcSB1, FcSB2 and FcSBCO containing hydrophobic ferrocenyl and carboranyl units as well as C=O group. Screening the proteinbinding behavior can signify the potential bioactivity of such molecules and may be helpful in the future development of promising multifunctional metallodrugs.展开更多
Hydrophobic fluorescence:Tan and his colleagues recently introduced a brand new chemotype of environment-sensitive fluorescent turn-on probes to detect the hydrophobic ligand-binding domain by using SBD fluorophore.Th...Hydrophobic fluorescence:Tan and his colleagues recently introduced a brand new chemotype of environment-sensitive fluorescent turn-on probes to detect the hydrophobic ligand-binding domain by using SBD fluorophore.The design strategy described in this report generalized the environment sensitivity turn-on mechanism to recognize a specific protein,which provides a robust breakthrough for interchanging fluorescence in conventional small-molecule fluorescent imaging.展开更多
文摘Influence of high light stress on the photosynthesis of flag leaves of indica subspecies (cv. “Shanyou 63', sensitive to photoinhibition) and japonica subspecies (cv. “Wuyujing', resistant to photoinhibition) of rice ( Oryza sativa L.) was comparatively investigated. In both cultivars of rice, the excitation energy distribution between two photosystems was altered and the excitation energy transfer from light harvesting chlorophyll protein complexes to PSⅡ was inhibited by high light stress. These decreases were more pronounced in indica rice cultivar as compared to japonica one. The analysis of mild SDS_PAGE showed that in indica rice, high light stress almost disaggregated the trimer of light harvesting chlorophyll protein complexes of PSⅡ (LHC Ⅱ 1). The stress reduced the contents of internal antennae chlorophyll protein complexes of PSⅡ (CPa), light harvesting chlorophyll protein of PSⅠ (CPⅠa) and Chl a protein complex of PSⅠ reaction center (CPⅠ) as well as dimer of LHCⅡ (LHCⅡ 2) in indica rice. In japonica subspecies, however, high light stress depressed the contents of LHCⅡ 1, CPa and CPⅠa, but slightly impacted on CPⅠ content. Moreover, the increase in the contents of monomer of LHCⅡ by high light stress was found in both subspecies. In consistent with above results, analysis of polypeptide indicated that the amounts of 27 kD and 25 kD polypeptide of LHCⅡ in particular, as well as that of 21 kD polypeptide of CPⅠa were reduced by high light stress in both subspecies. It was found that, comparing with japonica rice, the stress pronouncedly diminished 43 kD and 47 kD proteins of CPa and 23 kD extrisic protein in indica rice.
基金Supported by National "973" Program(2011CB100805)Optional Subjects of State Key Laboratory of Animal Nutrition(2008DA12518G0809)~~
文摘[Objective] The paper was to precisely predict nutrient requirements and optimize ration formula, and explore the inherent feature of ration optimization of dairy cow. [Method] Based on cornell net carbohydrate and protein system (CNCPS) with integrating dynamic prediction models on main nutrient requirements of dairy cattle recommended by NRC (2001) and the CNCPS parameter database accumu- lated by Chinese feed database, the ration nutrient requirement dynamic calculation and total mixed ration (TMR) formula optimizing system for Holstein dairy cow was developed using FOXPRO database system and parametric linear programming algo- rithm. [Result] By optimizing a specific cow ration and analyzing its completed nutri- ents, the results showed that this system could entirely consider a lots of nutrient balances, such as concentrate fraction and forage fraction balance, rumen degrad- able protein and rumen undergradable protein balance, crude protein and lactation net energy balance, fibrous substances (ADF, NDF) and non-fiber carbohydrates (NFC) balance, calcium and phosphate balance, electrolytes balance and trace ele- ment balance etc., and could also calculate intestinal amino acid flow in terms of different models. [Conclusion] By using dynamic mathematical equations and comput- erized program, it can be realized for the ration formula design of lactating cow with all-round interoperable but mutual-constraining each other among ration nutrients.
基金Supported by the National Natural Sciences Foundation of China(General Program: 3037030 30270657 and Key Program: 30230150) Early Phase Study Supported by the Key Basic Research Project (2002-CCA04100) the National High Technology Research and Devel
文摘Objective To deduce all potential ligands undiscovered experimentally by searching all the proteins containing same C-termini, which can bind a certain PDZ domain. Methods We developed a JAVA program for searching short exact sequence matches at C-terminus. According to the known C-termini, which PDZ domains recognized experimentally, Swissprot database has been searched by this program for all potential ligands. Results Some PDZ domains may have more potential ligand proteins, which are undiscovered yet experimentally. These bioinformatic results also provide clues for studying functions of hypothetical proteins and PDZ domains’ protein interactions in many different organisms. Conclusion The results may provide useful clues for discovering potential functions of hypothetical proteins and new functions of known proteins.
基金Supported by the National Natural Science Foundation of China (30572353)
文摘Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors known to play a pivotal role in regulations of metabolism. In order to yield soluble ligand binding domain of PPARδ (PPARδLBD) for screening ligands, the cDNA was amplified using total RNA from HepG2 cells by RT-PCR. Then the enzyme-digested product was inserted . downstream of the malE gene in the vectorpMAL-p2x, which encoded maltose-binding protein (MBP), resulting in the expression of an MBP-PPARδLBD fusion protein. The recombinant plasmid was transformed into E. coli TBI that was cultured shakily at 30 ℃, 200 r/min and induced by 0.4 mmol/L IPTG for 6 h. The cells were harvested by centrifugation and broken by sonication. The expressed fusion protein was soluble and accounted for 0.31 of the total protein in the supernatant. Western blot analysis showed that the expressed MBP-PPARδLBD could bind to anti-MBP-antibody. The MBP-PPARδLBD fusion protein of 77 kDa and the PPARδLBD protein of 34 kDa were obtained by amylose-resin affinity chromatography without or with digestion of Factor Xa. They were both homogeneity, judged by SDS-PAGE. The recombinant MBP-PPARδLBD and PPARδLBD protein with high purity is obtained, which provides the necessary material for screening and researching PPARδ ligands.
文摘Most protein-ligand interactions take place on surfaces and include but not limited to factors such as chemical composition, hydrophobicity, electronegavitiy and shape complementarity. Past studies showed that protein-protein interactions occur on comparatively fiat regions whereas protein-ligand bindings involve crevices. In the search for such sites various approaches have been designed and developed each of which is algorithmically unique. The use of grid units or voxels has been demonstrated in early studies with relatively good results obtained. We present here an approximated approach comprising of the use of voxels and computer vision methods in the search for ligand-binding areas. Each test protein is modelled and analysed in 2D with all corresponding residues graphically presented for successfully identified sites. The study was carried out on 2 sets of proteins: FK506-bound proteins and heme-bound proteins with promising results obtained for all test cases.
基金supported by the National Basic Research Program of China (2010CB732404, 2010CB923303)the National Natural Science Foundation of China (21175020, 90713023, 20925104)+4 种基金the Project of High Technology Research and Development Program of China (2007AA022007)Gongdong Province (2011B090400357)the Natural Science Foundation of Jiangsu Province (BK2008149, BK2010052)C. W. acknowledges the Fundamental Research Funds for the Central Universities (ZYGX2011J099)the support by the Open Research Fund of State Key Laboratory of Bioelectronics, Southeast University (2011E09)
文摘The interactions between the new organometallic complexes, ferrocenesubstituted dithioocarborane conjugates (denoted as FcSB1, FcSB2 and FcSBCO) and hemoglobin (Hb) are investigated by electrochemistry, fluorescence and UVvis absorption spectroscopy. The results demonstrate that FcSB1, FcSB2 and FcSBCO can bind to the heme iron center through the replacement of the weakly bound H20/02 in the distal heme pocket of Hb by their sulfur donor atoms, inducing the allosteric change from the R state (oxygenated conformation, relax) to T state (deoxygenated conformation, tense). The binding affinity is in the order of FcSBCO〉FeSB2〉FeSB1. Moreover, the fluorescence study illustrates that the three ferrocenecarborane conjugates differently affect the quarterly and tertiary structures as well as the polarity in the surrounding of the Trp and Tyr residues in Hb. Typically, FcSB2 mainly induces alterations of the microenvironment around the 1337Trp residue which is located on the cql32 interface of Hb. Such distinct influences are attributed to the structural features of FcSB1, FcSB2 and FcSBCO containing hydrophobic ferrocenyl and carboranyl units as well as C=O group. Screening the proteinbinding behavior can signify the potential bioactivity of such molecules and may be helpful in the future development of promising multifunctional metallodrugs.
基金supported by the National Natural Science Foundation of China (81370085)the Program of New Century Excellent Talents in University (NCET-11-0306)+2 种基金the Fok Ying Tong Education Foundation (122036)the Shandong Natural Science Foundation (JQ201019)the Independent Innovation Foundation of Shandong University (2010JQ005 and 2012JC002).
文摘Hydrophobic fluorescence:Tan and his colleagues recently introduced a brand new chemotype of environment-sensitive fluorescent turn-on probes to detect the hydrophobic ligand-binding domain by using SBD fluorophore.The design strategy described in this report generalized the environment sensitivity turn-on mechanism to recognize a specific protein,which provides a robust breakthrough for interchanging fluorescence in conventional small-molecule fluorescent imaging.