Characterization and manipulation of the photosystem Ⅱ-semiconductor interfacial molecular interactions in solar-to-chemical energy conversion

Semi-artificial photosynthesis interfacing catalytic protein machinery with synthetic photocatalysts exhibits great potential in solar-to-chemical energy conversion. However, characterizing and manipulating the molecular integration structure at the biotic-abiotic interface remain a challenging task. Herein,the biointerface molecular integration details of photosystem II(PSII)-semiconductor hybrids, including the PSII orientation, interfacial microdomains, and overall structure modulation, are systematically interrogated by lysine reactivity profiling mass spectrometry. We demonstrate the semiconductor surface biocompatibility is essential to the PSII self-assembly with uniform orientation and electroactive structure.Highly directional localization of PSII onto more hydrophilic Ru/Sr Ti O_(3):Rh surface exhibits less disturbance on PSII structure and electron transfer chain, beneficial to the high water splitting activity.Further, rational modification of hydrophobic Ru_(2)S_(3)/Cd S surface with biocompatible protamine can improve the hybrid O_(2)-evolving activity 83.3%. Our results provide the mechanistic understanding to the structure–activity relationship of PSII-semiconductor hybrids and contribute to their rational design in the future.

基于先进紫外光源的生物质谱技术的最新进展及展望

生物大分子质谱是研究复杂生命体系中分子的序列组成、动态结构、相互作用和空间分布的前沿科学领域.先进紫外光源特别是同步辐射、自由电子激光等大科学装置的发展,为光解离-串联质谱和光电离-质谱成像等生物大分子质谱研究尖端技术的进步提供了新的机遇.本综述中,我们总结了不同波长先进光源包括X射线、极紫外激光等在蛋白质、脂质等生物分子高效光解离和序列、结构、相互作用表征,光化学氧化标记和动态结构分析,高效光电离和高灵敏度质谱检测及空间分布成像等领域的研究进展;进一步展望了新一代先进紫外光源特别是具有更高亮度、更短脉冲、更高重频的极紫外自由电子激光在生物大分子质谱研究中的应用前景和可能带来的技术突破.

A metabolome atlas of mouse brain on the global metabolic signature dynamics following short-term fasting

Calorie restriction(CR)or a fasting regimen is considered one of the most potent non-pharmacological interventions to prevent chronic metabolic disorders,ameliorate autoimmune diseases,and attenuate aging.Despite efforts,the mechanisms by which CR improves health,particularly brain health,are still not fully understood.Metabolic homeostasis is vital for brain function,and a detailed metabolome atlas of the brain is essential for understanding the networks connecting different brain regions.

In-situ generation and global property profiling of metal nanoclusters by ultraviolet laser dissociation-mass spectrometry

Metal nanoclusters are promising nanomaterials with unique properties, but only a few ones with specific numbers of metal atoms can be obtained and studied up to now. In this study, we establish a new paradigm of in-situ generation and global study of metal nanoclusters with different sizes, constitutions, and charge states, including both accurate constitution characterization and global activity profiling. The complex mixtures of metal nanoclusters are produced by employing single-pulsed 193-nm laser dissociation of monolayer-protected cluster(MPC) precursors within a high-resolution mass spectrometry(HRMS). More than400 types of bare gold nanoclusters including novel multiply charged(2+ and 3+), S-/P-doped, and silver alloy ones can be efficiently generated and accurately characterized. A distinct size(1 to 142 atoms)-and charge(1+ to 3+)-hierarchy reactivity is clearly observed for the first time. This global cluster study might greatly promote the developments and applications of novel metal nanoclusters.

Elucidating the various multi-phosphorylation statuses of protein functional regions by 193-nm ultraviolet photodissociation

Ultraviolet photodissociation is a high-energy fast excitation method in mass spectrometry and has beensuccessfully applied for the elucidation of sequences and structures of biomolecules. However, its abilityto distinguish the phosphorylation sites isomers of multi-phosphopeptides has been not systematicallyinvestigated until now. A 193-nm ultraviolet laser dissociation mass spectrometry system wasestablished in this study and applied to elucidate the complex multi-phosphorylation statuses mimickingthe functional regions of Sicl, Gli3 and Tau. The numbers of matched fragment ions and phosphorylationsite-determining ions were improved on average 123% and 104%, respectively, by utilizing the ultravioletphotodissociation strategy, comparing to the typically utilized collision induced dissociation strategy.Finally. 94% phosphorylation sites within various statuses were unambiguously elucidated.

Elucidating the Molecular Mechanism of Dynamic Photodamage of Photosystem II Membrane Protein Complex by Integrated Proteomics Strategy

Photosystem II(PSII),as a multiple-subunit chloroplast membrane-associated pigment-protein complex on the thylakoid membrane,is a primary target of light-induced photodamage.However,the overall molecular details of the conformation and composition dynamics of PSII photodamage are still controversial.In this study,we investigated systematically the dynamic conformation,degradation,and oxidation processes of PSII photodamage by integrating chemical cross-linking and top-down proteomics strategies.

电化学氧化灭活新型冠状病毒

当前主要采用危害生物体和环境安全的消毒剂对引起新冠肺炎的SARS-CoV-2病毒进行消杀,从而阻断病毒传播.本文报道了一种绿色、高效的电化学消杀SARS-CoV-2病毒的装置和方法:采用Ni OOH作为阳极,泡沫镍为阴极,碳酸钠为电解液,在5 V恒电压电化学处理5 min后, SARS-Co V-2病毒的灭活效率高达99.99%.质谱分析结合理论计算模拟表明,在电解过程中阳极所产生的活性氧物种能够有效氧化并破坏SARS-Co V-2病毒S1蛋白的关键受体识别区域(RBD),从而实现病毒彻底灭活.这一绿色且高效的电化学灭活策略为阻断含有SARS-Co V-2病毒的气溶胶、污水等潜在传播途径提供了新的思路.