Volume changes in isolated myofibrils

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects Pub Date : 1964-11-29 DOI:10.1016/0926-6577(64)90095-6

R.J. Baskin

{"title":"Volume changes in isolated myofibrils","authors":"R.J. Baskin","doi":"10.1016/0926-6577(64)90095-6","DOIUrl":null,"url":null,"abstract":"<div>Volume changes in glycerol-extracted myofibrils were studied. The effect of pH, ion content and ATP concentration on the change in volume was determined. A volume change greater than that attributed to ATP dephosphorylation was observed. The magnitude of the volume change of the entire system was 10−3 cm3 whereas that due to dephosphorylation was 10−6 cm3. The ratio of ATPase activity in a volume decrease to that in a volume increase was found to be approx. 10:1. The total amount of volume decrease measured approx. 0.028 cm3/g of muscle with a fresh myo fibril preparation. The volume increase which was observed upon the addition of large amounts of ATP amounted to approx. 0.036 cm3/g of muscle. The relationship between the volume changes and molecular reorganization of the myofibril proteins was discussed. It was concluded that either a large configurational change occurs in the myofibril proteins during an ATP-induced contraction or relaxation, or that the volume changes are related to the dissociation and association of actin and myosin filaments</div>","PeriodicalId":100169,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1964-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6577(64)90095-6","citationCount":"5","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0926657764900956","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}

引用次数: 5

Abstract

Volume changes in glycerol-extracted myofibrils were studied. The effect of pH, ion content and ATP concentration on the change in volume was determined. A volume change greater than that attributed to ATP dephosphorylation was observed. The magnitude of the volume change of the entire system was 10⁻³ cm³ whereas that due to dephosphorylation was 10⁻⁶ cm³. The ratio of ATPase activity in a volume decrease to that in a volume increase was found to be approx. 10:1. The total amount of volume decrease measured approx. 0.028 cm³/g of muscle with a fresh myo fibril preparation. The volume increase which was observed upon the addition of large amounts of ATP amounted to approx. 0.036 cm³/g of muscle. The relationship between the volume changes and molecular reorganization of the myofibril proteins was discussed. It was concluded that either a large configurational change occurs in the myofibril proteins during an ATP-induced contraction or relaxation, or that the volume changes are related to the dissociation and association of actin and myosin filaments

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

离体肌原纤维的体积变化

研究了甘油提取肌原纤维的体积变化。测定了pH、离子含量和ATP浓度对体积变化的影响。观察到比ATP去磷酸化更大的体积变化。整个体系的体积变化幅度为10−3 cm3，而由于去磷酸化导致的体积变化幅度为10−6 cm3。体积减小时的atp酶活性与体积增大时的atp酶活性之比接近。10:1。测量到的体积减少总量约为。0.028 cm3/g的肌肉，用新鲜的肌原纤维制备。在加入大量ATP后观察到的体积增加约为。0.036 cm3/g肌肉。讨论了肌原纤维蛋白的体积变化与分子重组的关系。结论是，在atp诱导的收缩或松弛过程中，肌原纤维蛋白发生了大的结构变化，或者体积变化与肌动蛋白和肌球蛋白丝的解离和结合有关

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

Biochimica et Biophysica Acta (BBA) - Specialized Section on Biophysical Subjects

自引率

0.00%

发文量

期刊最新文献

Subject index Author index Photoreduction of nicotinamide-adenine dinucleotide by a cell-free system from Chromatium Chlorophylls of photosynthetic bacteria Photodimerization of urocanic acid in vitro and in vivo