Biochimica et Biophysica Acta-Bioenergetics最新文献

Stimulation of cytochrome c oxidase activity by detergents 清洁剂对细胞色素 c 氧化酶活性的刺激

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-09-07 DOI: 10.1016/j.bbabio.2024.149509

{"title":"Stimulation of cytochrome c oxidase activity by detergents","authors":"","doi":"10.1016/j.bbabio.2024.149509","DOIUrl":"10.1016/j.bbabio.2024.149509","url":null,"abstract":"<div>Cytochrome c oxidase (CytcO) is an integral membrane protein, which catalyzes four-electron reduction of oxygen linked to proton uptake and pumping. Amphipathic molecules bind in sites near the so-called K proton pathway of CytcO to reversibly modulate its activity. However, purification of CytcO for mechanistic studies typically involves the use of detergents, which may interfere with binding of these regulatory molecules. Here, we investigated the CytcO enzymatic activity as well as intramolecular electron transfer linked to proton transfer upon addition of different detergents to bovine heart mitoplasts. The CytcO activity increased upon addition of alkyl glucosides (DDM and DM) and the steroid analog GDN. The maximum stimulating effect was observed for DDM and DM, and the half-stimulating effect correlated with their CMC values. With GDN the stimulation effect was smaller and occurred at a concentration higher than CMC. A kinetic analysis suggests that the stimulation of activity is due to removal of a ligand bound near the K proton pathway, which indicates that in the native membrane this site is occupied to yield a lower than maximal possible CytcO activity. Possible functional consequences are discussed.</div>","PeriodicalId":50731,"journal":{"name":"Biochimica et Biophysica Acta-Bioenergetics","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0005272824004791/pdfft?md5=b1e7ca0b37361a04561096943b6c6ddd&pid=1-s2.0-S0005272824004791-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insights into electron transfer and bifurcation of the Synechocystis sp. PCC6803 hydrogenase reductase module 洞察 Synechocystis sp. PCC6803 氢酶还原酶模块的电子传递和分叉。

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-09-06 DOI: 10.1016/j.bbabio.2024.149508

{"title":"Insights into electron transfer and bifurcation of the Synechocystis sp. PCC6803 hydrogenase reductase module","authors":"","doi":"10.1016/j.bbabio.2024.149508","DOIUrl":"10.1016/j.bbabio.2024.149508","url":null,"abstract":"<div>The NAD+-reducing soluble [NiFe] hydrogenase (SH) is the key enzyme for production and consumption of molecular hydrogen (H2) in Synechocystis sp. PCC6803. In this study, we focused on the reductase module of the SynSH and investigated the structural and functional aspects of its subunits, particularly the so far elusive role of HoxE. We demonstrated the importance of HoxE for enzyme functionality, suggesting a regulatory role in maintaining enzyme activity and electron supply. Spectroscopic analysis confirmed that HoxE and HoxF each contain one [2Fe2S] cluster with an almost identical electronic structure. Structure predictions, alongside experimental evidence for ferredoxin interactions, revealed a remarkable similarity between SynSH and bifurcating hydrogenases, suggesting a related functional mechanism. Our study unveiled the subunit arrangement and cofactor composition essential for biological electron transfer. These findings enhance our understanding of NAD+-reducing [NiFe] hydrogenases in terms of their physiological function and structural requirements for biotechnologically relevant modifications.</div>","PeriodicalId":50731,"journal":{"name":"Biochimica et Biophysica Acta-Bioenergetics","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S000527282400478X/pdfft?md5=48c6997ccfd028521473cfcb1e16d60b&pid=1-s2.0-S000527282400478X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142156563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

D1-Tyr246 and D2-Tyr244 in photosystem II: Insights into bicarbonate binding and electron transfer from QA•− to QB 光系统 II 中的 D1-Tyr246 和 D2-Tyr244：对碳酸氢盐结合以及从 QA 到 QB 的电子传递的见解。

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-08-30 DOI: 10.1016/j.bbabio.2024.149507

{"title":"D1-Tyr246 and D2-Tyr244 in photosystem II: Insights into bicarbonate binding and electron transfer from QA•− to QB","authors":"","doi":"10.1016/j.bbabio.2024.149507","DOIUrl":"10.1016/j.bbabio.2024.149507","url":null,"abstract":"<div>In photosystem II (PSII), D1-Tyr246 and D2-Tyr244 are symmetrically located at the binding site of the bicarbonate ligand of the non-heme Fe complex. Here, we investigated the role of the symmetrically arranged tyrosine pair, D1-Tyr246 and D2-Tyr244, in the function of PSII, by generating four chloroplast mutants of PSII from Chlamydomonas reinhardtii: D1-Y246F, D1-Y246T, D2-Y244F, and D2-Y244T. The mutants exhibited altered photoautotrophic growth, reduced PSII protein accumulation, and impaired O2-evolving activity. Flash-induced fluorescence yield decay kinetics indicated a significant slowdown in electron transfer from QA•− to QB in all mutants. Bicarbonate reconstitution resulted in enhanced O2-evolving activity, suggesting destabilization of bicarbonate binding in the mutants. Structural analyses based on a quantum mechanical/molecular mechanical approach identified the existence of a water channel that leads to incorporation of bulk water molecules and destabilization of the bicarbonate binding site. The water intake channels, crucial for bicarbonate stability, exhibited distinct paths in the mutants. These findings shed light on the essential role of the tyrosine pair in maintaining bicarbonate stability and facilitating efficient electron transfer in native PSII.</div>","PeriodicalId":50731,"journal":{"name":"Biochimica et Biophysica Acta-Bioenergetics","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142114442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Regulating the activity of mouse and human UCP1 调节小鼠和人类 UCP1 的活性

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-08-26 DOI: 10.1016/j.bbabio.2024.149180

引用次数: 0

Why do top journals accept papers containing fundamental bioenergetic errors? 为什么顶级期刊接受包含基本生物能错误的论文？

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-08-26 DOI: 10.1016/j.bbabio.2024.149108

引用次数: 0

Monotopic quinone reductases from Staphylococcus aureus: The two alternative NADH: quinone oxidoreductases are players with different molecular and cellular roles 金黄色葡萄球菌的单位醌还原酶：两种可供选择的 NADH：醌氧化还原酶具有不同的分子和细胞作用

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-08-26 DOI: 10.1016/j.bbabio.2024.149132

引用次数: 0

Respiratory complexes and supercomplexes of the model yeast S. cerevisiae 模式酵母 S. cerevisiae 的呼吸复合体和超级复合体

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-08-26 DOI: 10.1016/j.bbabio.2024.149133

引用次数: 0

Role of HIGD proteins in controlling respiratory complex assembly and function HIGD 蛋白在控制呼吸复合体组装和功能方面的作用

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-08-26 DOI: 10.1016/j.bbabio.2024.149122

引用次数: 0

UCP2 and UCP3: fraternal twins with distinct metabolic functions UCP2 和 UCP3：具有不同代谢功能的异卵双胞胎

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-08-26 DOI: 10.1016/j.bbabio.2024.149183

引用次数: 0

Innovations in Mitochondrial Research: Exploring Exercise-Induced Mitochondrial Adaptations in Skeletal Muscle 线粒体研究的创新：探索运动诱导的骨骼肌线粒体适应性

IF 3.4 2区生物学

Biochimica et Biophysica Acta-Bioenergetics Pub Date : 2024-08-26 DOI: 10.1016/j.bbabio.2024.149156

引用次数: 0