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Science in China,Ser.B 1988年第6期31卷 695-701页

作者：裘慕绥金由辛李文琴包俊茹龚佩娟吴仁龙郑可沁王德宝 Shanghai institute of biochemistry academia sinica

Analogues of yeast alanyl tRNA with I34 replaced by A34 or G34 were synthesized. Synthetic analoguesof yeast alanyl tRNT occupy the same position as the natural yeast alanyl tRNA on polyacrylamide gelelectrophoresis, and their purity is about 95% after electrophoresis on a 10% or 20% polyacrylamide *** two terminal and nearest neighbour nucleotides of the analogues are all correct. The accepting acti-vity of the synthetic analogues is similar to that of the reconstituted natural yeast alanyl tRNA. The in-corporation activity of alanine into proteins of the synthetic analogues is about 30% of that of the naturalof reconstituted natural yeast alanyl tRNA when I34 is replaced by A, and is 90% when I34 is replaced *** reason of the variation in biological function of the analogues of yeast alanyl tRNA after I34 re-placed by A or G was discussed.

关键词： tRNA BIOLOGICAL FUNCTION OF MODIFIED NUCLEOTIDES IN tRNA MOLECULES OR G

PURIFICATION AND SOME PROPERTIES OF GLYCEROL-3-PHOSPHATE DEHYDROGENASE FROM RABBIT SKELETAL MUSCLE MITOCHONDRIA

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Science in China,Ser.B 1986年第10期29卷 1027-1038页

作者：施善平刘建华林其谁 Shanghai institute of biochemistry academia sinica

Glycerol-3-phosphate dehydrogenase (E. C. 1. 1. 99. 5) was solubilized from rabbit skeletal muscle mitochondria by Triton X-100 and purified through hydroxyapatite column chromatography, DEAE-Sepharose CL-6B column chromatography and sucrose density gradient ultracentrifugation. The preparation was electrophoretically pure, the total recovery was 10% and the specific activity had been increased 200-fold. The apparent molecular weight of the enzyme polypeptide was 69,000, it existed in the form of enzyme-Triton X-100 complex with a Stokes’ radius of 59 and a sedimentation coefficient of 10.7S. There were 1.7mg Triton X-100 and 26 μg phospholipid per mg protein of the preparation. The enzyme absorbed at 410 and 460 nm which could be attributed to non-haem iron and FAD respectively. Both of the absorption would be largely diminished by adding the substrate glycerol-3-phosphate.

关键词： FAD PURIFICATION AND SOME PROPERTIES OF GLYCEROL-3-PHOSPHATE DEHYDROGENASE FROM RABBIT SKELETAL MUSCLE MITOCHONDRIA DEAE der Pro

A HYPOTHESIS OF DNA STRUCTURE——INSPIRATION FROM THE TOPOLOGICAL TRANS-FORMATION OF SUPERCOILED DNA

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Science in China,Ser.B 1982年第8期25卷 827-836页

作者：徐有成钱力陶宗晋 Shanghai institute of biochemistry academia sinica

The tertiary structure of supercoiled DNA will be changed if it reacts with glyoxal undercertain conditions. By the reversible reaction of glyoxal with DNA, we have observed topo-logical transformations among different forms of supercoiled DNA. It is difficult to account for the electrophoretic behavior and the electronmicroscopicpattern of the reaction product by the Watson-Crick double helix model. We would like tosuggest a hypothesis concerning the tertiary structure of DNA which seems to be moreapplicable to the explanation of various facts and related phenomena.

关键词： INSPIRATION FROM THE TOPOLOGICAL TRANS-FORMATION OF SUPERCOILED DNA A HYPOTHESIS OF DNA STRUCTURE

DNA FRAGMENTS OF Bombyx mori NUCLEAR POLYHEDROSIS VIRUS CONTAINING THE PROMOTERS ACTIVE IN PROKARYOTES

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Science China Chemistry 1987年第6期30卷 591-598页

作者：忻纪厚顾懋治李洪华王珩周金涛李敏棠李载平 Shanghai institute of biochemistry academia sinica

Using a promoter probe plasmid in E. coli called pHE5, eight different HindⅢ and one SalⅠDNAfragments of Bombyx mori nuclear polyhedrosis virus, directing the expression of the tetracycline re-sistance gene, have been cloned and isolated. The tetracycline resistance levels of the strains containing therecombinant plasmids were measured. Among them, the highest level of the resistance to tetracyclinewas 30μg/ml. Part of the nucleotide sequence of a DNA fragment was determined. A sequence similarto the E. coli promoter was found.

关键词： DNA FRAGMENTS OF Bombyx mori NUCLEAR POLYHEDROSIS VIRUS CONTAINING THE PROMOTERS ACTIVE IN PROKARYOTES gene

A SPIN LABELING STUDY OF PIG CARDIAC TROPOMYOSIN

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Science China Chemistry 1989年第3期32卷 324-334页

作者：叶红萍王华黎盛沛根邹永水 Shanghai institute of biochemistry Academia Sinica

Tropomyosin (TM) extracted from pig cardiac muscle was spin-labeled with 2,2,6,6-tetramethyl-4-(dichlorotriazin)-aminopiperidine-1-oxyl. The ESR spectra of the product (SL-TM) were of a type of weak immobilization. Effects of three means for the denaturation were observed on the above spectra. The ESR spectrum obtained for SL-TMafter enzymatic degradation was found to be analogous to that for the label itself in a dilute solution and thereby the quantity of labels bound in SL-TM estimated. The Arrhenius plots attained through variable temperature measurement for SL-TM’s exhibited two inflexion points (the conformational transition temperatures for TM) around 45℃ and 74-75℃, the latter temperature having not been reported in literature so far. However, the enzymatic degradation product from SL-TM behaved quite differently from it in the response to microwave power saturation and temperature variation.

关键词： cardiac tropomyosin ESR 2 2 6 6-tetramethyl-4-(dichlorotriazin)-aminopiper idide-l-oxyl.

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THE CLONING AND EXPRESSION OF THE SYNTHETIC LEU-ENKEPHALIN GENE IN ***

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Science in China,Ser.B 1984年第1期27卷 28-36页

作者：敖世洲梁镇和汤锦炎周晓雄丁晓华陈常庆李载平 Shanghai institute of biochemistry academia sinica

The synthetic leu-enkephalin (LEK) gene was joined with pBR322 and transformed toE. coli. The recombinant plasmids containing the LEK gene were selected by colony hybri-dization, and characterized by restriction mapping and Southern’s technique. The lac operonwas used to control the expression of the LEK gene. A recombinant plasmid, pEL 103, inwhich the lac operon and LEK gene are transcribed in the same direction, produces LEK inE. coli. The level of LEK detected by radioimmunoassay reaches 426 ng per mg of bacte-rial protein.

关键词： LEK gene

LIMITED TRYPTIC DIGESTION OF LEUCYL-tRNA SYNTHETASE AND CHARACTERIZATION OF ITS ACTIVE FRAGMENT

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Science China Chemistry 1989年第5期32卷 534-542页

作者：缪枫施建平王应睐 Shanghai institute of biochemistry Academia Sinica

Leucyl-tRNA synthetase (LeuRS, EC 6.***.1.4) from E. coli underwent limitedproteolysis by trypsin which cut off 6K peptide and converted the intact LeuRS into a 96K fragment. The truncated enzyme retained the PPi exchange activity with the same kinetic parameters as those of native LeuRS but lost the tRNA^(Leu)charging, binding and other tRNA^(Leu)-related activities. N-terminus analysis showed that the 6K peptide was located at the C-terminus of LeuRS. This small part played a crucial role in tRNA^(Leu) binding. Our results suggest that the two activities, PPi exchange and tRNA charging are independent of each other and correspond to different structural regions of LeuRS. The C-terminal region might be the tRNA^(Leu)binding site of LeuRS.

关键词： synthetase limited tryptic digestion active fragment.

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CONFORMATION OF Asn-Ala-Gly-Ala-Asn AND ITS DERIVATIVES IN SOLUTION——A CD SPECTRA ANALYSIS

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Science in China,Ser.B 1983年第1期26卷 25-32页

作者：鲁子贤施溥涛 Shanghai institute of biochemistry academia sinica

The CD method has been used to study the conformation of the pentapeptido Asn-Ala-Gly-Ala-Asn（NAGAN） and the tetrapeptides Asn-Ala-Gly-Ala（NAGA） and Asn-D-Ala-Gly-Ala-NH2（NDAGA） in solution. At low pH the far UV CD speetra of aqueous solutions of NAGAN show a positive extremum at 215 nm and a negative extremum at 232.5 nm. Under this condition, the molecule of NAGAN may assume a β-turn structure. In the solution of 90% ethanol or tri-fluoroethanol at pH 5.8, NAGAN reveals CD spectra with a negative 218 nm extremum. The[θ]218 values are independent of the concentration of NAGAN. Au intramolecular β-pleated sheet-like structure is suggested to explain the negative *** CD spectra of NAGA show a single positive band at around 215 nm. The possibility of forming a β-turn by NAGA has been discussed. Only the 196 nm negative extremum canbe seen in the spectra of NDAGA: It seems as if NDAGA is in the form of a random *** to the report made by Pan et al. all these peptides possess analgesic

关键词： CONFORMATION OF Asn-Ala-Gly-Ala-Asn AND ITS DERIVATIVES IN SOLUTION A CD SPECTRA ANALYSIS Gly CD ITS

THE CATCH MECHANISM OF MOLLUSCAN SMOOTH MUSCLES

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Science in China,Ser.B 1984年第6期27卷 583-589页

作者：陈国贤曹天钦 Shanghai institute of biochemistry academia sinica

We have examined the arrangements of the thick and thin filaments of the smooth mus-cle of the adductor of the bivalve Cristaria plicata, Leach, in the catch state induced byacetylcholine, both in ultrathin sections and in separate filaments. The thick filaments areheavily bent and entangled and the thin filaments irregularly arranged. One thin filamentmay be attached to several thick filaments. When the muscle is in the relaxed state, the twokinds of filaments are seen to be in Parallel. However, no difference could be observed in theperiodic strusture of the paramyosin core of the thick filaments in the relaxed state or in *** cross-striated and checkerboard types coexist. It seems that phase transition is not di-rectly related to catch. We propose that the disordered arrangements of the thick and thinfilaments and the formation of three-dimensional anastomosed networks are the structural basisfor catch, with a consequent loss of the capability of directional sliding of the filaments andrequiri

关键词：撇撇 Th THE CATCH MECHANISM OF MOLLUSCAN SMOOTH MUSCLES

THE PROTEIN SUBUNITS OF THE DOUBLESTRANDED RNA DEPENDENT RNA POLYMERASE AND METHYLTRANSFERASE OF THE CYTOPLASMIC POLYHEDROSIS VIRUS OF SILKWORM, Bombyx mori

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Science China Chemistry 1986年第12期29卷 1267-1272页

作者：戴仁鸣巫爱珍孙玉昆 academia sinica Shanghai institute of biochemistry

The particles of CPV of silkworm contain double-stranded RNA polymerase and methyltransferase. It was reported in a previous paper that the genome-enzyme complex could be isolated. The genome-enzyme complex shows high enzyme activity of RNA polymerase and methyltransferase in spite of the fact that it consists of only 5 percent of the protein. In order to clarify the protein subunits of the RNA polymerase and methyltransferase, two methods were adopted. The SDS-polyacrylamide gel electrophoretogram showed that theI-labeled genome-enzyme complex of CPV contained three protein components in molccular weight of 33 K, 67 K and 142 K daltons respectively and each protein component of them consisted of more than two protein subunits with different isoelectric points in 2-dimensional electrophoretogram. The antibody to the five protein components （P1, P2, P3, P4, P5） was prepared and used to inhibit the enzyme activities of RNA polymerase and mthyltransferase. It showed that the RNA polymerase was inhib

关键词： CPV THE PROTEIN SUBUNITS OF THE DOUBLESTRANDED RNA DEPENDENT RNA POLYMERASE AND METHYLTRANSFERASE OF THE CYTOPLASMIC POLYHEDROSIS VIRUS OF SILKWORM Bombyx mori RNA