Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects最新文献_第8页

Light-induced rapid absorption changes during photosynthesis 光合作用过程中光诱导的快速吸收变化

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90149-4

Bacon Ke

{"title":"Light-induced rapid absorption changes during photosynthesis","authors":"Bacon Ke","doi":"10.1016/0926-6577(64)90149-4","DOIUrl":"10.1016/0926-6577(64)90149-4","url":null,"abstract":"<div>Rapid absorption changes can be induced by short light flashes in Ochromonas danica. The absorption change rises in 10−4 sec or less and has a half life of 35–40 msec. The complex difference spectrum has positive peaks at 443, 475, 505 and 580 mμ and negative peaks at 490 and 535 mμ.The absorption change is very sensitive to physical treatments. Heating to 40° for 2 min or sonicating at 10 kcycles for 1 sec completely eliminates the signal.The absorption change remains unaffected by resuspending the organism in a “starvation” medium or by making the medium anaerobic. The presence of several oxidants or reductants, KCN, and iodoacetamide has no noticeable effects on the absorption changes.3-(3,4-dichlorophenyl)-1,1-Dimethylurea at 10−7 and 10−6M reduces the magnitude of the absorption change by 50 and 75%, respectively. A residual activity (about 20%) persists up to 0.5 mM 3-(3,4-dichlorophenol)-1,1-dimethylurea. 2,4-Dinitrophenol reduces the absorption change and accelerates the decay, whereas carbonyl cyanide m-chlorophenylhydrazone only lengthens the decay. H2O2 both reduces the magnitude of the absorption change and lenghtens the decay.</div>","PeriodicalId":100169,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1964-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6577(64)90149-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40765817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Héterogénéité de la chlorophylle in vivo 叶绿素在体内的变性

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90151-2

Jean Lavorel

{"title":"Héterogénéité de la chlorophylle in vivo","authors":"Jean Lavorel","doi":"10.1016/0926-6577(64)90151-2","DOIUrl":"10.1016/0926-6577(64)90151-2","url":null,"abstract":"<div>A former study of chlorophyll fluorescence in Chlorella had lead to the distinction of several fractions of the chlorophyll holochrome: A photoreceptive fraction Chl0 and two fractions Chl1685 and Chl1720 the excition of which was sensitized by the first one. The Chl1685 fraction has a potochemical function and is responsible for the variable yield emission. The constant yield emission maily comes from Chl0 and to a lesser extent from Chl1720.By studies of fluorescence polarisation, this scheme of excitation transfers is confirmed; moreover, the Chl1720 fraction has a certain amount of direct absorption and a high degree of orientation.The variation of fluorescence yield during the induction period is seen as resulting from the distribution of the Chl1685 fraction between at least two forms: the non-fluorescent O form and the fluorescent P form. Action spectra of the Chl1685 show in the far red a difference between the photochemical production of the P form and the excitation of its fluorescence. This difference can be understood in the theory of two photochemical systems of photosynthesis as resulting from the antagonistic action of each system on the P form.The general scheme of electron transport in photosynthesis and the concept of structural separation of the sensitizers of the two systems are discussed.</div>","PeriodicalId":100169,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1964-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6577(64)90151-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83892247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 28

The electron-microscopic stucture and chemical composition of the isolated sarcolemma of the rat skeletal muscle cell 大鼠骨骼肌细胞分离肌膜的电镜结构和化学成分

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90163-9

Tetsuro Kono , Fumiko Kakuma, Mitsunobu Homma, Shoichi Fukuda

引用次数: 35

Separation of subcellular particles by density-gradient electrophoresis 用密度梯度电泳分离亚细胞颗粒

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90164-0

J.B. Davenport

引用次数: 18

Anoxia in parietal cells of the frog gastric mucosa 青蛙胃粘膜壁细胞缺氧

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90176-7

Leopoldo Villegas

引用次数: 7

Konfiguration und längenverteilung von DNA-molekülen in lösung 溶液中的dna分子组织的结构及经度分布

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90162-7

Dimitrij Lang , Albrecht K Kleinschmidt , Rudolf K Zahn

{"title":"Konfiguration und längenverteilung von DNA-molekülen in lösung","authors":"Dimitrij Lang , Albrecht K Kleinschmidt , Rudolf K Zahn","doi":"10.1016/0926-6577(64)90162-7","DOIUrl":"10.1016/0926-6577(64)90162-7","url":null,"abstract":"<div>A diffusion method is described for visualization of DNA molecules which is equivalent to the spreading of a mixed DNA-protein solution. Macromolecules diffusing in a solution of about 5×10−8 g DNA per ml are adsorbed by a cytochrome c-film at the air-water interface. Subsequently they are transferred to electron microscopic supports. In the enlarged two-dimensional image the end-to-end distances and the length distribution are measured for different DNA preparations (from cod fish, trout, holothuria and T2 phage). Following recalculation in the three-dimensional state a relation is given for the mean square of the end-to-end distances, <math><mtext>h</mtext><msup><mi></mi><mn>2</mn></msup></math>, and the length, L, as <math><mtext>(</mtext><mtext>h</mtext><msup><mi></mi><mn>2</mn></msup><mtext>)</mtext><msup><mi></mi><mn><mtext>1</mtext><mtext>2</mtext></mn></msup><mtext> = 1.3 × 10</mtext><msup><mi></mi><mn>−1</mn></msup><mtext> L(1 + √</mtext><mtext>1 + 2.3 × 10</mtext><msup><mi></mi><mn>−3</mn></msup><mtext>L</mtext></math> at ionic strengths from 0.09 to 0.35, according to a theory by Katchalsky and Lifson for diluted linear polyelectrolytes. The molecular shape is not a random coil or a rod but intermediate on account of electrostatic interaction. An application of the results on the theory of Kuhn, Kuhn and Buchner yields equations for the diffusion coefficient or other characteristics of DNA as a function of length or molecular weight. The length distribution of DNA, after disintegration by preparation and storage, usually has the form of a descending exponential function. Within the accuracy of the length distribution it is allowed to deduce random scissions along the native DNA molecule.</div>","PeriodicalId":100169,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1964-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6577(64)90162-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72450823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 36

Transients in glycolytic metabolism following electrical activity in electrophorus electrophus电活动后糖酵解代谢的瞬变

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90159-7

P.K. Maitra, A. Ghosh, B. Schoener, B. Chance

{"title":"Transients in glycolytic metabolism following electrical activity in electrophorus","authors":"P.K. Maitra, A. Ghosh, B. Schoener, B. Chance","doi":"10.1016/0926-6577(64)90159-7","DOIUrl":"10.1016/0926-6577(64)90159-7","url":null,"abstract":"<div>The cyclic increases and decreases of fluorescence emission of slices of the main organ of Electrophorus electricus which have been interpreted as DPN+ reduction at the glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12) site are here correlated with assays of essential intermediates of glycolysis. Large increases of fructose 1,6-diphosphate, glyceraldehyde 3-phosphate, 3-phosphoglyceric acid and 2-phospholgyceric acid are found to occur at the time of the maximum increases of fluorescence and to have subsided as the flourescence increase subsides. Measurements of increased DPN concentration and glyceraldehyde 3-phosphate concentration identify the fluorescence increase with DPN+ reduction at glyceraldehyde-3-phosphate dehydrogenase. The activation of glycolysis appears to be due to a concentrated effect of increased ADP and creased ATP concentration upon phosphofructokinase (EC 2.7.1.11), 1,3-diphosphojlycerate kinase (EC 2.7.2.3) and glyceraldehyde-3-phosphate dehydrogenase. The possibility of other activators of phosphofructokinase is also to be considered.</div>","PeriodicalId":100169,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1964-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6577(64)90159-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40765809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 22

Anomalous diffraction spectra of biological cells 生物细胞的异常衍射光谱

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90165-2

Tamako Kurozumi , Kazuo Shibata

{"title":"Anomalous diffraction spectra of biological cells","authors":"Tamako Kurozumi , Kazuo Shibata","doi":"10.1016/0926-6577(64)90165-2","DOIUrl":"10.1016/0926-6577(64)90165-2","url":null,"abstract":"<div>Anomalous diffraction spectra of monolayers of biological cells dried on a quartz plate were observed between 0.25 and 2.5 μ. The possibility of using the positions of the diffraction maxima and minima for the determination of cell dimensions was examined on the basis of a simple theory of anomalous diffraction for spherical or discoidal cells. In the spectra region used, yeast and Chlorella cells showed two diffraction maxima, and spinach chloroplasts and human erythrocytes a single maximum. The relative wavelengths of the two maxima and the minimum between them were in the ratios calculated from the theory, so that it was possible to evaluate a term proportional to the cell diameter or thickness. The proportionality between the evaluated quantity and the diameter was examined with yeast, Chlorella cells, cloroplasts, and erythrocytes, and was approximately constant. A semi-empirical formula for the determination of cell dimensions was obtained by assuming the average of the proportionality constants for these different species of cells. The maximum error due to this assumption and due to the variation of the content of solid materials in cells was estimated to be 13% in diameter. The diffraction method was compared with other optical or microscopic methods for the determination of cell dimensions.</div>","PeriodicalId":100169,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1964-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6577(64)90165-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40765816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

An application of the Rayleigh optics of the ultracentrifuge to molecular weight determinations by the Archibald method 超离心机瑞利光学在阿奇博尔德法测定分子量中的应用

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90166-4

Joe L. Roberts, Gene F. Conway

引用次数: 2

Nitrogen fixation and photosynthesis in a subcellular fraction of the blue-green alga Anabaena cylindrica 蓝藻白柱水藻亚细胞部分的固氮和光合作用

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-07-29 DOI: 10.1016/0926-6577(64)90168-8

R.M. Cox, P. Fay, G.E. Fogg

引用次数: 26