Genome‐wide selection for increased copy number in Acinetobacter baylyi ADP1: locus and context‐dependent variation in gene amplification

摘要: Renewed interest in gene amplification stems from its importance evolution and a variety of medical problems ranging drug resistance to cancer. However, amplified DNA segments (amplicons) are not fully characterized any organism. Here we report novel Acinetobacter baylyi system for genome-wide studies. Amplification mutants that consume aromatic compounds were selected under conditions requiring high-level expression three promoters linked set chromosomal genes. Tools developed relocate these catabolic genes non-essential position, 49 five genomic contexts characterized. Amplicon size (18-271 kb) copy number (2-105) indicated 30% carried more than 1 Mb DNA. features depended on position. For example, amplicons one locus similarly sized but displayed variable number, whereas those another differently had comparable number. Additionally, the sequence context was highlighted region where differed depending presence promoter mutation strain which they selected. sequences at amplicon boundaries 19 reflected illegitimate recombination. Furthermore, steady-state duplication frequencies measured non-selective (10(-4) 10(-5) ) confirmed spontaneous is major source genetic variation.