请问,世界上最长的单词是什么?

最长的单词是smiles ,因为两个字母S中间隔了一英里

“色氨酸合成酶A蛋白质”

（一种含有267种氨基酸酶）的全称----

一般的字典上是见不着的。

（你可以翻翻医学专用词汇字典^_*）

单词如下：

Methionylglutaminylarginyltyrosylglutamylserylleucylphenylalanylalany

lglutaminylleucyllysylglutamylarginyllysylglutamylglycylalanylphenyla

lanylvalylprolyphenylalanYlvalythreonylleucylglycylaspartylprolylglyc

ylisoleucylglutamylglutaminylsErylleucyllysylisoleucylaspartylthreony

lleucylIsoleucylglutamylalanylglycylalanylasparthlalanylleucylglutamy

lleucylglycylisoleucylprolylphenylalanylseRylaspartylprolylleucylalan

ylaspartylglycylpRolylthreOnylisoleucylglutaminylasPfraginylalanylthr

eonylleucylarfinylalanylphenylalanylalanylalanylglycylvalythreonylpro

lylalanylglutaminylcysteinylphenylalanylglutamylmethionylleucylalanyl

leuOylisoleucylarginylglutaminyllysyhistidylprolylthreonylisoleucylpr

olylisole