The top 20 highest-paid biopharma CEOs 1. Len Schleifer, Regeneron $41.97 million. Schleifer may have popped up on our CEO pay list just a few years ago--and stayed at or near the top--but he's been plugging away at Regeneron since he founded the company in 1988.
Most bacterial species contain a single type of chromosome, but it may be present in multiple copies. Several thousand different genes are interspersed throughout the chromosome; structural gene sequences (encoding proteins) account for the majority of bacterial DNA; nontranscribed DNA sequences between adjacent genes are termed intergenic regions.
Furthermore, some bacteria have linear chromosomes. Borrelia 3 have linear chromosomes and most strains contain both linear and circular plasmids; most of the bacteria in the genus Streptomyces 4 have linear chromosomes and plasmids and some have circular plasmids as well. For example, linear DNA was precipitated in the most commonly used procedures for purifying bacterial plasmids, and the procedures for purifying chromosomal DNA relied upon the differential binding of ethidium bromide to sheared DNA fragments compared to circular DNA.