世界上英文单词最长的是什么？

背英语单词这是每个小伙伴都经历过的事情吧？对于学霸而言，这点小小的事情，根本什么都不算。

smiles
两个s中间有一里长。 （脑筋急转弯的话）

世上最长的英语单词
据疯狂英语2001，九月，第30期载：

最长的是1，913个字母，

是“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

olylisoleucylglycylleucylmethionyltyrosylalanylasparaginylleucylvalyl

phenylalanylasparaginyllysyglycylisoleucylaspartylglutamylphenylalany

lthrosylalanylglutaminylcysteinylglutamyllysylvalylglycylvalylasparty

lserylvalylleucylvalylalnylaspartylvalylprolylvalylglUtaminylglutamyl

serylalanylprolylphenylalanylarginylglutaminylalanylalanylleucylarginy

lhistidylasparaginyvalylalanylprolylisoleucylprolylisoleucylphenylalan

ylisoleucylphenylalanylisoleucylcysteinylprolylprolylaspartylalanylasp

artylaspartylaspartylleucylleucylarginylglutaminylisoleucylalanylseryl

tyrosylglycylarginylglycyltyrosylthreonyltyrOsylleucylleucylserylargin

ylalanylglycylvalylthreonylglycylalanylglutamYlasparainylarginylalanyl

alanylleucylprolylleucylasparaginylhistidylleucylValylalanyllysylleucy

llysylglutamyltyrosylasparaginylalanylalanylprolylprolylleucylglutaminy

lglgycylphenylalanylglycylisoleucylserylalanylprolylaspartylglutaminylv

alyllysylalanylalanylisoleucylaspartylalanylglycylalanylalanylglycylala

nylisoleucylserylglycylserylalanylisoleucylvalyllysylisoIeucylisoleucyl

glutamylglutaminylHistidylasparaginyliSoleucylglutamylprolylglutamyllys

ylmethionylleucylalanylalanylleucyllysylvalylphenylalanylcalylglutaminy

lprolylmethionlysylalanylalanylthreonylarginylserine

世界上最长的单词是什么？