上游充通大学 SHANGHAI JIAO TONG UNIVERSITY 1.Proteins Are Built from a Repertoire of 20 Amino Acids R (3) 蛋白质的结构单元 H(4) R H (2) (1) NH3 L isomer NH3* D isomer S configuration Figure 2.4 The L and D isomers of amino acids.L and D isomers are mirror images of each other.Only L amino acids are found in proteins
1.Proteins Are Built from a Repertoire of 20 Amino Acids Figure 2.4 The L and D isomers of amino acids. L and D isomers are mirror images of each other. Only L amino acids are found in proteins S configuration 蛋白质的结构单元
上海充通大学 SHANGHAI JIAO TONG UNIVERSITY 1.Proteins Are Built from a Repertoire of 20 Amino Acids Distinctive R goroup:sides,shape,charge, hydrogenbonding capacity,hydrophobic character.... H+ +H3N COOH +H3N H2N coO H+ H+ 兼性离子 Zwitterionic Both groups form deprotonated Both groups protonated 0 2 4 6 8 10 12 14 PH lonization state as a function of pH
1.Proteins Are Built from a Repertoire of 20 Amino Acids Ionization state as a function of pH. Distinctive R goroup: sides, shape, charge, hydrogenbonding capacity, hydrophobic character…. 兼性离子
上游充通大学 1.Proteins Are Built from a SHANGHAI JIAO TONG UNIVERSITY Repertoire of 20 Amino Acids Distinctive R goroup: >按侧链结构划分： >按侧链性质划分： Aliphatic (15) I)Non-polar (8) Aromatic (3) Aliphatic (5) Heterocyclic (2) Aromatic (2) Heterocyclic (1) (3) Il)Polar（12)活性基团 H(4) Uncharged (1+1+2+3) (2) Acidic (2) (1) NH3 00 Basic (3) L isomer
1.Proteins Are Built from a Repertoire of 20 Amino Acids I）Non-polar （8） Aliphatic（5） Aromatic（2） Heterocyclic（1） II）Polar（12）活性基团 Uncharged（1+1+2+3） Acidic （2） Basic （3） 按侧链结构划分： 按侧链性质划分： Aliphatic（15） Aromatic（3） Heterocyclic（2） Distinctive R goroup:
上游充通大￥ SHANGHAI JIAO TONG UNIVERSITY 1.Proteins Are Built from a Repertoire of 20 Amino Acids (1)非极性氨基酸： R基为脂肪侧链（5)： H3 H2 +H3N H3N coo H3N +H3N H3N C00 CH3 +H3N C00- CH3 H H CH3 Alanine C00 HaN COO- +H3N- C00 (Ala,A) H H H Valine Leucine Isoleucine Methionine (Val.V) (Leu.Ll (lle-I1 (Met.M) 丙氨酸 缬氨酸 亮氨酸 异亮氨酸 甲硫氨酸
1.Proteins Are Built from a Repertoire of 20 Amino Acids 丙氨酸 R基为脂肪侧链（5）： （1）非极性氨基酸： 缬氨酸 亮氨酸 异亮氨酸 甲硫氨酸
上游充通大学 SHANGHAI JIAO TONG UNIVERSITY 1.Proteins Are Built from a Repertoire of 20 Amino Acids (1)非极性氨基酸： R基为脂肪侧链（5)： 名称你 结构与功能特点 异亮氨酸、亮氨酸、 均含有较大的疏水侧链，其刚性结构特征及疏水相互作用都对蛋白折 缬氨酸 叠有重要的影响力，常作为水溶性蛋白的内部支撑结构 是多肽链生物合成的起始氨基酸；参与体内含硫化合物代谢及甲基化 甲硫氨酸 反应 丙氨酸 转氨酶中的氨基供体
名称你 结构与功能特点 异亮氨酸、亮氨酸、 缬氨酸 均含有较大的疏水侧链，其刚性结构特征及疏水相互作用都对蛋白折 叠有重要的影响力，常作为水溶性蛋白的内部支撑结构 甲硫氨酸 是多肽链生物合成的起始氨基酸；参与体内含硫化合物代谢及甲基化 反应 丙氨酸 转氨酶中的氨基供体 R基为脂肪侧链（5）： （1）非极性氨基酸： 1.Proteins Are Built from a Repertoire of 20 Amino Acids