Complex sentence: Discovered by Arthur Kornberg in 1956, it was the first known DNA polymerase (and, indeed, the first known polymerase of any kind), and was initially characterized in "E. coli", although it is ubiquitous in prokaryotes.
Split into simpler sentences: Discovered by Arthur Kornberg in 1956, it was the first known DNA polymerase (and, indeed, the first known polymerase of any kind). It was initially characterized in "E. coli", although it is ubiquitous in prokaryotes.