His 标签:H 占 35 mol%,S 占 25 mol%,GRAVY = −1.19 6×His 标签 MGSSHHHHHHSSGLVPRGSH 在组成表中明显偏极性:仅组氨酸就占 7/20 = 35 mol%(6×His 区段加 C 端 1 个),丝氨酸 5/20 = 25 mol%。Kyte–Doolittle GRAVY = −23.8/20 = −1.19,相当亲水——这正是折叠蛋白表面溶剂暴露的亲和标签所需要的性质。{"result":"Composition of 20 residues: H 35.00 mol%, S 25.00 mol%, G 15.00 mol%; GRAVY = −1.19 (hydrophilic).","metadata":{"result":{"length":20,"counts":{"H":7,"S":5,"G":3},"molPercent":{"H":35},"gravy":-1.19}}}
聚丙氨酸 AAAAAAAAAA:GRAVY = +1.80,A = 100 mol% 十聚丙氨酸是疏水性自检:丙氨酸(Kyte–Doolittle 标度 1.80)占 100 mol%,使 GRAVY 恰为 +1.80、脂肪族分组 10/10。真实序列中很少出现这种同聚物得分——整条平均超过 +0.5 的天然蛋白通常嵌在膜里或难溶。{"result":"Composition of 10 residues: A 100.00 mol%; GRAVY = 1.8 (hydrophobic).","metadata":{"result":{"length":10,"counts":{"A":10},"molPercent":{"A":100},"gravy":1.8}}}