Journal of mechanochemistry & cell motility最新文献

Gliding edge dislocations and flipping in the conformational change of helical proteins. 螺旋蛋白构象变化中的滑边错位和翻转。

Journal of mechanochemistry & cell motility Pub Date : 1977-12-01

W F Harris, H D Chandler, H R Hepburn

引用次数: 0

Incorporation of the Ca2+ -binding component (g2) into heavy meromyosin and subfragment-1 of pig cardiac myosin. Ca2+结合组分(g2)掺入猪心肌肌球蛋白的重肌球蛋白和亚片段-1。

Journal of mechanochemistry & cell motility Pub Date : 1977-12-01

H Kuwayama, K Yagi

{"title":"Incorporation of the Ca2+ -binding component (g2) into heavy meromyosin and subfragment-1 of pig cardiac myosin.","authors":"H Kuwayama, K Yagi","doi":"","DOIUrl":"","url":null,"abstract":"A new protein component was found in heavy meromyosin and in subfragment-1 (S-1) prepared by chymotrypsin digestion of pig cardiac myosin in the presence of Ca2+. The molecular weight of this protein was estimated as 15,000 dalton. It was able to bind Ca2+ and showed a similar UV absorption spectrum to that of the g2 light chain. Heavy meromyosin and subfragment-1 which contained the 15,000 dalton component incorporated exogenous g2 and the 15,000 dalton component disappeared after such treatment. We concluded that the 15,000 dalton component was produced from g2 by limitted proteolysis. The subfragment-1 was separated into two protein fractions in equal yield by recycling the gel filtration. One contained the 15,000 dalton component and was able to bind Ca2+ while the other did not contain the component and was unable to bind Ca2+. According to analysis by SDS gel electrophoresis, the large polypeptide chain (the f component) of the first S-1 was approximately 5,000 dalton larger than the f component of the second S-1. The polypeptide corresponding to 5,000 dalton was designated polypeptide-C, because it was released from the C terminal of the f component. It seems to be essential for the attachment of the Ca2+-binding light chain g2. The location of g2 in myosin may thus be at the polypeptide-C which links the head to the tail of myosin.","PeriodicalId":76011,"journal":{"name":"Journal of mechanochemistry & cell motility","volume":"4 4","pages":"255-74"},"PeriodicalIF":0.0,"publicationDate":"1977-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11588626","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: 0

Model of the bacterial flagellar motor: response to varying viscous load. 细菌鞭毛马达的模型:对不同粘性载荷的响应。

Journal of mechanochemistry & cell motility Pub Date : 1977-12-01

G Adam

引用次数: 0

Numerical study of the behavior of an activation parameter in a sliding filament cat papillary muscle model. 滑动细丝猫乳头肌模型中激活参数行为的数值研究。

Journal of mechanochemistry & cell motility Pub Date : 1977-12-01

T S Feit, B G Bass

{"title":"Numerical study of the behavior of an activation parameter in a sliding filament cat papillary muscle model.","authors":"T S Feit, B G Bass","doi":"","DOIUrl":"","url":null,"abstract":"A previously existing model of cross-bridge kinetics is modified to make it applicable to cardiac muscle and incorporated into a macroscopic model of isolated heart muscle. Equations are formulated which describe the responses of this model during simulated isometric and isotonic contractions. These equations allow one to calculate the time variation of the activation parameter in the model when given the contraction time history, i.e. the time course of length and tension changes. The activation parameter is defined as the instantaneous rate constant for cross bridge attachment. We calculate the time course of the activation parameter with the model's responses set equal to the measured responses of isolated cat papillary muscle and the model parameters chosen appropriately for cat papillary muscle. It is found that in order for the model and muscle response to match, the degree of activation of the muscle model must first increase and then decrease with shortening. The behavior of the activation parameter in the muscle model is consistent with physiological investigations which suggest that shortening in cardiac muscle is associated with both activation and deactivation.","PeriodicalId":76011,"journal":{"name":"Journal of mechanochemistry & cell motility","volume":"4 4","pages":"275-302"},"PeriodicalIF":0.0,"publicationDate":"1977-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11953732","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: 0

Chemotaxis and movement of Physarum polycephalum and its responses to some neurotransmitters and psychomimetic compounds. 多头绒泡菌的趋化性和运动及其对某些神经递质和拟精神物质的反应。

Journal of mechanochemistry & cell motility Pub Date : 1977-09-01

I Chet, A Naveh, Y Henis

引用次数: 0

Tension generation by isolated myofibrils. 分离的肌原纤维产生张力。

Journal of mechanochemistry & cell motility Pub Date : 1977-09-01

J Borejdo, A Schweitzer

引用次数: 0

Computer simulation of flagellar movement. V. oscillation of cross-bridge models with an ATP-concentration-dependent rate function. 鞭毛运动的计算机模拟。V.具有atp浓度依赖速率函数的过桥模型振荡。

Journal of mechanochemistry & cell motility Pub Date : 1977-09-01

C J Brokaw, D Rintala

引用次数: 0

Relation of membrane vesicles to volume and Na+ transport in smooth muscle: effect of metabolic and transport inhibition on fresh tissues. 膜泡与平滑肌体积和Na+运输的关系:代谢和运输抑制对新鲜组织的影响。

Journal of mechanochemistry & cell motility Pub Date : 1977-06-01

R E Garfield, E E Daniel

{"title":"Relation of membrane vesicles to volume and Na+ transport in smooth muscle: effect of metabolic and transport inhibition on fresh tissues.","authors":"R E Garfield, E E Daniel","doi":"","DOIUrl":"","url":null,"abstract":"We tested the hypothesis that membrane vesicles of smooth muscle function as organelles controlling cell volume through a mechanochemical mechanism not involving Na+-K+ dependent membrane ATPase. Pieces of rat myometrium were incubated under various conditions at 25 degrees C, and then were analyzed after various times for Na+, K+, ATP and water contents or were prepared and examined in the electron microscope. Metabolic inhibition with iodoacetate (IAA) + dinitrophenol (DNP) rapidly depleted ATP, then decreased membrane vesicle number and increased vesicle size. Thereafter K+ loss, Na+ gain and water gain occurred. Slower depletion of ATP by treatment of tissues with IAA or ethacrynic acid produced similar, but delayed effects. Treatment with DNP alone, DNP in glucose-free Krebs-Ringer or glucose-free solution bubbled with N2 partly depleted the tissues of ATP but did not markedly affect the membrane vesicles or tissue water content. Ouabain affected neither ATP contents of tissues nor the numberof membrane vesicles, but produced large intracellular vesicles. The membrane vesicles were suggested to be sites of a mechanochemical volume control system.","PeriodicalId":76011,"journal":{"name":"Journal of mechanochemistry & cell motility","volume":"4 2","pages":"113-55"},"PeriodicalIF":0.0,"publicationDate":"1977-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11375187","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: 0

Relation of membrane vesicles to volume control and Na+-transport in smooth muscle: studies on Na+-rich tissues. 膜泡与平滑肌体积控制和Na+转运的关系:富Na+组织的研究。

Journal of mechanochemistry & cell motility Pub Date : 1977-06-01

R E Garfield, E E Daniel

{"title":"Relation of membrane vesicles to volume control and Na+-transport in smooth muscle: studies on Na+-rich tissues.","authors":"R E Garfield, E E Daniel","doi":"","DOIUrl":"","url":null,"abstract":"Correlation between operation of a volume control system (independent of Na+-K+ -ATPase) and membrane vesicle structure was examined in strips of rat myometrium made Na-rich by incubation in Krebs-Ringer solutions at 5 degrees C. Some pieces of tissue were analyzed for Na+, K+, ATP and water contents before and after rewarming to 37 degrees C. Other pieces of tissue were prepared and examined in the electron microscope. The membrane vesicles along the surface of the muscle cells were reduced from the numberin fresh tissues made Na+-rich by overnight incubation in K+-free Ringer solution at 5 degrees C. Rewarming of Na+-rich tissues under conditions thought to inhibit Na+-K+-ATPase caused the loss of Na+ with water and with utake of K+ but the vesicles did not increase in number. Na+-K+ATPase activity was suggested to inhibit vesicle formation by competing for ATP. The loss of water and increase in vesicle number was Ca2+-dependent but did not require Na+. Inhibition of the volume control system by iodoacetamide, Ca2+-free solution and other procedures resulted in swelling of membrane vesicles. The membrane vesicles were suggested to be sites of a mechanochemical system of volume control and the mechanochemical step was suggested to involve discharge of membrane vesicles.","PeriodicalId":76011,"journal":{"name":"Journal of mechanochemistry & cell motility","volume":"4 2","pages":"157"},"PeriodicalIF":0.0,"publicationDate":"1977-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11375188","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: 0

Is the 9+2 pattern of flagellar and ciliary axonemes an efficient arrangement for generating planar bending? 鞭毛和纤毛轴突的9+2模式是产生平面弯曲的有效安排吗?

Journal of mechanochemistry & cell motility Pub Date : 1977-06-01

C J Brokaw

引用次数: 0