Adhesin gene of Mycoplasma genitalium exists as multiple copies

The structural gene of the 140 kDa adhesin of Mycoplasma genitalium was used to probe M. genitalium genomic DNA for gene copy number. Since multiple banding patterns were observed, the 140 kDa structural gene was subdivided into 10 contiguous fragments in size from 165 to 657 base pairs in order to determine which parts of the adhesin gene existed as multiple copies. Each fragment was labeled by nick translation and used to probe the entire M. genitalium genomic DNA. Approximately half the gene was present in single copy while the remaining sequences were multiple copied. Both single and multiple copy regions were interspersed throughout the structural gene.