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為甚麼Taq可以耐高溫工作為甚麼肉類要低溫保鮮 (引注資料 (https://www.ncbi.nlm.nih…

- - - - 三個domain：
        – Polymerase Activity
        – 3’ to 5’ Exonuclease - Fix errors
        – 5’ to 3’ Exonuclease – Remove RNA or DNA in “front” of primer
      - The fact that there is significant similarity in native states but dissimilarity in stability, points to the involvement of denatured states.
      - The DNA polymerase from Thermus aquaticus (Taq polymerase) is homologous to Escherichia coli DNA polymerase I (Pol I) and likewise has domains responsible for DNA polymerase and 5' nuclease activities
        Taq酶跟E.coli的pol同源，都有domain可以去做5'的活性
    - - glycine: 沒有支鏈，具有較大彈性
      - proline:被用作提高蛋白質穩定度的胺基酸
        
        Thermodynamic effects of proline introduction on protein stability.
        https://goo.gl/vBt2oX
      - arginine:形成salt bridge
        
        A Study on the Effect of Surface Lysine to Arginine Mutagenesis on Protein Stability and Structure Using Green Fluorescent Protein
        https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3392243/
    - - Crystal structure of Taq has more stable interactions (or less unfavorable interactions) compared E. coli Pol I polymerase, nothing significant to explain thermostability
      - Folding enthalpy of Taq polymerase is less than that of E. coli Pol I polymerase. Taq is more stable due to reduced entropic penalty of folding
      - Many thermophilic proteins are stable at high temperatures due to enthalpic contributions. That is, more hydrogen bonds/salt bridges/non-covalent interactions
      - 氫鍵在一定的溫度下就會有機率被打斷，氫鍵的形成則是依照原子間的距離而生成，所以重點應該在整個骨架
        
        Taq跟pol的結構非常像，而差別是在序列上的不同
- - - - 蛋白質就是看結構，但是兩者好像？
        
        明明都是依靠氫鍵、雙硫鍵、鹽橋，為何Taq就是比較耐高溫？
        
        回去看序列
        
        序列：
        TP has more arginines instead of lysines, more glycines instead of alanines, more prolines instead of alanines, and a slight increase in hydrophobic residue content.
        
        glycine: 沒有支鏈，具有較大彈性
        
        proline:被用作提高蛋白質穩定度的胺基酸
        
        Thermodynamic effects of proline introduction on protein stability.
        https://goo.gl/vBt2oX
        
        arginine:形成salt bridge
        
        A Study on the Effect of Surface Lysine to Arginine Mutagenesis on Protein Stability and Structure Using Green Fluorescent Protein
        https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3392243/