PL73 Brevibacterium consists of genetically modified strain of Brevibacterium lactofermentum/Corynebacterium glutamicum, named SO317/pCABL used to produce the amino acid L-lysine.

The strain SO317/pCABL consists of the recipient strain SO317 and the low copy number plasmid pCABL (about 8-10 copies per cell). pCABL contains a 4451 bp fragment of a naturally occuring plasmid of C. glutanicum 2256, 5 functional elements derived from C. glutamicum related to the L-lysine production; the E. coli Ori sequences and the selection gene nptI providing resistance to kanamycin.

The purpose of the genetic modification is to increase the ability to produce L-lysine by fermentation on substrates of agricultural origin.