Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis最新文献_第8页

Experimentelle untersuchungen über die bedeutung der imidazolringe für das assoziationsvermögen von insulunmolekülen 给她做实验，判别模拟键如何影响局部分子的简单联想反应

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-09-05 DOI: 10.1016/0926-6585(66)90047-1

Werner Schaeg, Horst Finger, Helmut Niemann

引用次数: 4

The egress of oxygen from sheep erythrocytes after mixing with sodium dithionite 绵羊红细胞与二亚硝酸钠混合后的氧气输出

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-09-05 DOI: 10.1016/0926-6585(66)90033-1

John A. Sirs

{"title":"The egress of oxygen from sheep erythrocytes after mixing with sodium dithionite","authors":"John A. Sirs","doi":"10.1016/0926-6585(66)90033-1","DOIUrl":"10.1016/0926-6585(66)90033-1","url":null,"abstract":"<div>Spectrophotometric measurements, using the rapid-mixing technique, have been made of the initial rate of egress of oxygen from HbO2 in sheep erythrocytes after mixing with dithionite. This rate is <math><mtext>18 </mtext><mtext>sec</mtext><msup><mi></mi><mn>−1</mn></msup><mtext> ± 20%</mtext></math> at 25° and the activation energy is <math><mtext>14 </mtext><mtext>kcal</mtext><mtext> ± 20%</mtext></math> for HbB. No variation was found with a change of oxygen concentration from 0.075–0.35 mM at 10°, nor with a change of Na2S2O4 concentration from 4–12 g/l. The rate of dissociation was found to be greater, during the later part of the reaction, with the stopped-flow system as compared with the constant-flow technique. An analysis of the results suggests that the cell membrane has negligible resistance to the egress of oxygen and that the initial rate is determined by the chemical reaction of <math><mtext>HbO</mtext><msub><mi></mi><mn>2</mn></msub><mtext> → </mtext><mtext>Hb</mtext></math>. It is also suggested that the internal contents of the erythrocyte may be effectively mixed.</div>","PeriodicalId":100158,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis","volume":"126 1","pages":"Pages 28-36"},"PeriodicalIF":0.0,"publicationDate":"1966-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6585(66)90033-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17042857","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: 7

Fluorine superhyperfine structure in EPR spectra of the single crystal of the myoglobin fluoride 氟化肌红蛋白单晶EPR光谱中的氟超细结构

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-09-05 DOI: 10.1016/0926-6585(66)90050-1

H. Morimoto, M. Kotani

引用次数: 12

The site of action of cysteamine in irradiated bacteria: An electron spin resonance study 半胱胺在辐照细菌中的作用部位:电子自旋共振研究

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-09-05 DOI: 10.1016/0926-6585(66)90034-3

A. Baker , M.G. Ormerod , C.J. Dean , P. Alexander

{"title":"The site of action of cysteamine in irradiated bacteria: An electron spin resonance study","authors":"A. Baker , M.G. Ormerod , C.J. Dean , P. Alexander","doi":"10.1016/0926-6585(66)90034-3","DOIUrl":"10.1016/0926-6585(66)90034-3","url":null,"abstract":"<div>Electron spin resonance spectra showed that radicals produced in Escherichia coli B/r and Micrococcus radiodurans by exposure to γ-rays at −195° undergo a series of changes on warming. Cysteamine modifies these reactions in a characteristic manner, but the full effect is only seen if the bacteria are ruptured by mechanical methods prior to the addition of cysteamine. With intact M. radiodurans cysteamine has almost no effect on the ESR spectra seen after irradiation, while with E. coli B/r cysteamine already has some influence before irradiation possibly because the cells are damaged to some extent by freeze-drying. The data are interpreted as showing that cysteamine does not penetrate into the interior of non-metabolizing bacteria, yet it protects against the lethal action of ionizing radiations under these conditions. Physicochemical experiments had shown earlier that main-chain scission of DNA extracted from irradiated bacteria was not protected by cysteamine. The hypothesis is advanced that cysteamine protects a metabolic repair system of DNA which is situated at or near the cell membrane, and in this way makes the restitution of DNA lesions more efficient in irradiated bacteria.</div>","PeriodicalId":100158,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis","volume":"126 1","pages":"Pages 37-42"},"PeriodicalIF":0.0,"publicationDate":"1966-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6585(66)90034-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15398668","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

Effect of glucose and other carbon compounds on the transport of α-methylglucoside in Escherichia coli K12 葡萄糖和其他碳化合物对大肠杆菌K12中α-甲基葡萄糖苷转运的影响

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-09-05 DOI: 10.1016/0926-6585(66)90046-X

Yeheskel S. Halpern, Meir Lupo

{"title":"Effect of glucose and other carbon compounds on the transport of α-methylglucoside in Escherichia coli K12","authors":"Yeheskel S. Halpern, Meir Lupo","doi":"10.1016/0926-6585(66)90046-X","DOIUrl":"10.1016/0926-6585(66)90046-X","url":null,"abstract":"<div>The effect of glucose, succinate, sorbitol, glycerol and arabinose on the rate of uptake of α-[14C]methylglucoside by Escherichia coli K12 was studied in comparison with the effect of these substances on the rate of α-methylglucoside exit from cells preloaded with the radioactive compound.Glucose was a very potent inhibitor of uptake and greatly accelerated exit, its effect on the former reaction exceeding four-fold that on the latter. Each of the other compounds tested was much less active than glucose and affected both uptake and exit of methylglucoside to a similar extent.The inhibition of uptake and the acceleration of exit by glucose were not affected by sodium azide. On the other hand, azide practically abolished the effect of succinate and glycerol, both on the uptake and exit reactions and reduced to 50% the effect of sorbitol.These results provide further support for the conclusion reached by Hoffeeet al. that α-methylglucoside is transported by a glucose permease and that the inhibitory effect of metabolizable compounds on its uptake is due to energy supply for the exit reaction. Another possible mechanism for acceleration of exit in the presence of hexitols and sugars is also discussed.</div>","PeriodicalId":100158,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis","volume":"126 1","pages":"Pages 163-167"},"PeriodicalIF":0.0,"publicationDate":"1966-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6585(66)90046-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"16421099","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: 11

Emission spectra of Chlorella at very low temperatures (−269° to −196°) 小球藻在极低温(−269°~−196°)下的发射光谱

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-09-05 DOI: 10.1016/0926-6585(66)90049-5

F. Cho, J. Spencer, Govindjee

引用次数: 39

Biophysical properties of phospholipids. II. Permeability of phosphatidylserine liquid crystals to univalent ions 磷脂的生物物理性质。2。磷脂酰丝氨酸液晶对单价离子的渗透性

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-09-05 DOI: 10.1016/0926-6585(66)90053-7

Demetrios Papahadjopoulos , Alec D. Bangham

引用次数: 97

Studies on plasma membranes III. Mg2+-ATPase, (Na+-K+-Mg2+)-ATPase and 5′-nucleotidase activity of plasma membranes isolated from rat liver 质膜的研究III。Mg2+- atp酶、(Na+-K+-Mg2+)- atp酶和5′-核苷酸酶活性的研究

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-07-13 DOI: 10.1016/0926-6585(66)90304-9

P. Emmelot, C.J. Bos

{"title":"Studies on plasma membranes III. Mg2+-ATPase, (Na+-K+-Mg2+)-ATPase and 5′-nucleotidase activity of plasma membranes isolated from rat liver","authors":"P. Emmelot, C.J. Bos","doi":"10.1016/0926-6585(66)90304-9","DOIUrl":"10.1016/0926-6585(66)90304-9","url":null,"abstract":"<div><ul><li>1.1. Plasma membranes have been isolated from rat liver and the ATPase (EC 3.6.1.4), (Na+-K+)-ATPase and 5′-nucleotidase (EC 3.1.3.5; substrate: AMP) activities of the preparations have been studied.</li><li>2.2. The pH-, Mg2+-, temperature- and concentration-dependences and the nucleotide specificity of the ATPase and nucleotidase were established.</li><li>3.3. The ATPase and (Na+-K+)-ATPase of the isolated plasma membranes hydrolyzed the terminal phosphate bond of ATP. The following effects on the two enzymes were obtained: Ca2+, ouabain, cysteine, p-chloromercuribenzoate, Myleran and oligomycin inhibited the (Na+-K+)-ATPase while having no effect on the ATPase. Ultrasound, oleic acid, vitamin A alcohol and deoxycholate inhibited both ATPases. Bile, deoxycholate (at low concentration), Lubrol-W, deoxycorticosterone acetate and progesterone inhibited ATPase and activated the (Na+-K+)-ATPase. Activation of the ATPase and inhibition of the (Na+-K+)-ATPase could be obtained by saponin and preincubation of the membranes at 37°.</li><li>4.4. None of the treatments inhibited the nucleotidase; ultrasound, deoxycholate, saponin and Lubrol-W activated the enzyme.</li><li>5.5. The results are discussed in regard to the relation between membrane structure and enzymic function.</li></ul></div>","PeriodicalId":100158,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis","volume":"120 3","pages":"Pages 369-382"},"PeriodicalIF":0.0,"publicationDate":"1966-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6585(66)90304-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15332031","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: 235

Experiments on the extraction and photoconversion of chenopodium chlorophyll protein CP 668 藜草叶绿素蛋白cp668的提取和光转化实验

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-07-13 DOI: 10.1016/0926-6585(66)90298-6

Willemke Terpstra

{"title":"Experiments on the extraction and photoconversion of chenopodium chlorophyll protein CP 668","authors":"Willemke Terpstra","doi":"10.1016/0926-6585(66)90298-6","DOIUrl":"10.1016/0926-6585(66)90298-6","url":null,"abstract":"<div><ul><li>1.1. The amount of extractable, photoconvertible, protein-chlorophyll complex CP 668 from Chenopodium album leaves was found to be very variable, depending on site and day of leaf collection.</li><li>2.2. Photoconversion of CP 668 into a 740-nm absorbing form probably does not occur in intact leaves; CP 668 in its extracted form is concluded to be an artifact.</li><li>3.3. CP 668 may be separated from other “soluble”, non-photoconvertible material absorbing at about 668 nm by precipitation with polyethyleneglycol</li><li>4.4. CP 740, the phototransformed form of CP 668, does not show any clear absorption band in ethanol. It is suggested that the 740-nm band arises from interaction of photo-oxidized chlorophyll with protein.</li><li>5.5. Photoconversion of CP 668 into CP 740 is promoted by lowering the pH from about 8 to 6.</li><li>6.6. Photoconversion of CP 668 is inhibited by β-mercaptoethanol and KCN; it is slightly inhibited in Tris buffer as compared with phosphate buffer.</li><li>7.7. In discussing the experiments it is suggested that CP 668 is a denatured form of a native chlorophyll-protein complex containing essential SH groups.</li></ul></div>","PeriodicalId":100158,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis","volume":"120 3","pages":"Pages 317-325"},"PeriodicalIF":0.0,"publicationDate":"1966-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6585(66)90298-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17075670","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: 9

Density-gradient banding of denatured deoxyribonucleic acid in cesium sulphate 变性脱氧核糖核酸在硫酸铯中的密度梯度带

Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis Pub Date : 1966-07-13 DOI: 10.1016/0926-6585(66)90311-6

Donald J. Cummings, Lee Mondale

引用次数: 10