为什么《本草纲目》把朱砂等矿物当药？
Why did the Compendium of Materia Medica list minerals like cinnabar as medicine?
李时珍记载朱砂（硫化汞）、雄黄等入药，反映古人对矿物药的经验认知；现代已知汞、砷有毒，多已禁用。
Li Shizhen's Compendium listed cinnabar (HgS) and realgar as drugs, showing early mineral pharmacology; modern science recognizes their mercury/arsenic toxicity.
难度 专业 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03
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《无机化学》生物无机化学章节
Inorganic Chemistry (bioinorganic chemistry); Nature
#本草纲目 #矿物药 #李时珍
为什么章鱼和蜗牛的血是蓝色的？
Why is the blood of octopus and snail blue?
它们用血蓝蛋白携氧，其中含铜，含氧时呈蓝色、缺氧时偏无色；与人的血红蛋白（含铁，呈红）不同。
They use hemocyanin, a copper-based oxygen carrier that is blue when oxygenated (nearly colorless without)—unlike iron-based red hemoglobin.
难度 专业 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03
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《无机化学》生物无机化学章节
Inorganic Chemistry (bioinorganic chemistry); Nature
#血蓝蛋白 #铜 #携氧
固氮酶为什么必须借助铁钼辅因子才能在常温常压下还原N₂？ATP水解在其中起什么作用？
Why does nitrogenase need its iron–molybdenum cofactor to reduce N₂ at ambient conditions, and what role does ATP hydrolysis play?
N≡N三键键能约940 kJ/mol，哈伯法需高温高压催化；固氮酶靠铁钼辅因子（FeMo-co）这一多金属硫簇活化N₂：电子从P簇逐个传入辅因子，质子与电子按Lowe–Thorneley方案偶合加入，绕开高能中间体。每传递一个电子要先水解两个ATP，以保证电子单向流动并提升还原力，从而在常温常压下把N₂还原为氨。
The N≡N triple bond (~940 kJ/mol) forces the Haber–Bosch process to run hot, pressurized, and catalyzed. Nitrogenase instead activates N₂ on the FeMo-cofactor, a multi-metal sulfide cluster: electrons enter one by one from the P-cluster while protons join in the coupled steps of the Lowe–Thorneley sequence, bypassing high-energy intermediates. Two ATP must be hydrolyzed per electron delivered, enforcing one-way flow and boosting reducing power, so the enzyme fixes nitrogen under mild conditions.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-02
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B. M. Hoffman、D. Lukoyanov、Z.-Y. Yang、D. R. Dean、L. C. Seefeldt《Nitrogenase: A Draft Mechanism》，Acc. Chem. Res.，2013年，第46卷，595页（DOI: 10.1021/ar300367c）
B. M. Hoffman, D. Lukoyanov, Z.-Y. Yang, D. R. Dean & L. C. Seefeldt, "Nitrogenase: A Draft Mechanism", Acc. Chem. Res., 2013, 46, 595 (DOI: 10.1021/ar300367c)
独立核验依据 · Independent verification: 核验依据 1 CROSSREF 标识 10.1021/ar300267m：Nitrogenase: A Draft Mecha
#生物无机化学 #固氮酶 #铁钼辅因子
细胞色素P450的关键中间体Compound I是什么结构，为何它能温和地氧化药物分子中的惰性C-H键？
What is the structure of cytochrome P450 Compound I, and why can it oxidize unactivated C-H bonds in drug molecules so mildly?
它是催化循环中的高价铁氧物种：血红素铁为Fe(IV)=O，卟啉环另带一个π阳离子自由基，轴向由半胱氨酸硫负离子锚定，氧化力远超普通血红素蛋白。它先夺取底物C-H键的氢原子，生成碳自由基和Fe(IV)-OH，随即氧回弹把羟基交回自由基位点，完成羟化。全过程在水相近中性条件下进行，这是药物I相代谢既强效又温和的原因。
Compound I is the high-valent iron-oxo species at the heart of the catalytic cycle: the heme iron sits as Fe(IV)=O, the porphyrin ring carries an extra pi-cation radical, and a cysteinate axial ligand anchors the heme, pushing its oxidizing power far beyond ordinary globins. It first abstracts a hydrogen atom from a substrate C-H bond to give a carbon radical plus Fe(IV)-OH, then undergoes oxygen rebound, transferring the hydroxyl back onto the radical site to finish hydroxylation. The whole sequence proceeds in near-neutral aqueous conditions, which is why phase-I drug metabolism is both powerful and gentle.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-04
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Pang,《Why high spin? Why sulphur? Comparative analysis of catalytic oxidation by Compound I of cytochrome P450, catalase, peroxidase, and selenocysteine-modified P450》,Computational and Theoretical Chemistry,2024 (DOI: 10.1016/j.comptc.2024.114720)
Pang, 'Why high spin? Why sulphur? Comparative analysis of catalytic oxidation by Compound I of cytochrome P450, catalase, peroxidase, and selenocysteine-modified P450', Computational and Theoretical Chemistry, 2024, DOI: 10.1016/j.comptc.2024.114720
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1016/j.comptc.2024.114720; Comput Theor
#细胞色素P450 #高铁氧中间体 #氧回弹 #药物代谢
碳酸酐酶为什么必须依赖Zn²⁺才能实现CO2的超快速水合？锌离子在活性位点究竟起什么作用？
Why does carbonic anhydrase need Zn2+ to hydrate CO2 so rapidly, and what exactly does the zinc ion do at the active site?
Zn²⁺被三个组氨酸和一个水分子配位，把配位水的pKa从约15降到接近7，因此生理pH下就能生成亲核性的锌-羟基去进攻CO2并释放HCO3-；随后水分子回填空位完成循环。锌的路易斯酸性与His64质子梭协同，使转换频率高达每秒约一百万次。
Zn2+, held by three histidines and one water molecule, lowers the pKa of bound water from about 15 to nearly 7, so at physiological pH a nucleophilic zinc-bound hydroxide attacks CO2 and releases bicarbonate; water then rebinds to close the cycle. Zinc's Lewis acidity acts together with the His64 proton shuttle to push turnover to roughly one million per second.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-03
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D.W. Christianson & C.A. Fierke, Accounts of Chemical Research, 1996, 29, 331-339
D.W. Christianson and C.A. Fierke, Acc. Chem. Res., 1996, 29, 331-339, DOI: 10.1021/ar9501232
独立核验依据 · Independent verification: 核验依据 1 CROSSREF 标识 10.1021/ar9501232：Carbonic Anhydrase: Evolut
#锌酶 #碳酸酐酶 #路易斯酸催化
顺铂这种铂（II）配合物，是靠怎样的配位化学让癌细胞的DNA无法完成复制的？
How does cisplatin, a platinum(II) complex, use coordination chemistry to stop the DNA of cancer cells from replicating?
顺铂先经水解活化，再交联DNA。细胞外氯离子浓度高，顺铂的两个氯配体安稳不动；进入细胞后氯离子浓度骤降，水分子取而代之，生成亲电的活性物种。铂继而与DNA上鸟嘌呤的N7位配位，主要在同一条链相邻两个鸟嘌呤间架起1,2-链内交联，双螺旋局部弯折，复制与转录受阻，损伤累积最终触发细胞凋亡。只有顺式构型能完成这类邻位交联，故反式异构体几乎无效。
Cisplatin first activates itself by aquation, then crosslinks DNA. Outside the cell, plentiful chloride holds the two chloride ligands in place; once inside, chloride levels plunge and water molecules take over, yielding electrophilic aqua species. Platinum then coordinates the N7 site of guanines, most often bridging two neighboring guanines on the same strand into a 1,2-intrastrand crosslink. The helix kinks locally, replication and transcription stall, and accumulating damage finally triggers apoptosis. Only the cis geometry can manage these adjacent bindings, so the trans isomer is nearly worthless as a drug.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-02
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B. Rosenberg 等，《自然（Nature）》，1965年，第205卷，698至699页
B. Rosenberg, L. VanCamp and T. Krigas, Inhibition of cell division in Escherichia coli by electrolysis products from a platinum electrode, Nature, 1965, vol. 205, pp. 698-699
独立核验依据 · Independent verification: 核验依据 1 CROSSREF 标识 10.1038/205698a0：Inhibition of Cell Division
#顺铂 #配位化学 #DNA交联