Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: 7/14/2002
Publication Date: N/A
Technical Abstract: Spiroplasma kunkelii is a cell wall-less phloem-inhabiting bacterium that causes corn stunt disease. As a part of the S. kunkelii Genome Sequencing Project, we analyzed an 85 kbp DNA segment from the pathogenic S. kunkelii strain CR2-3x. This genome segment contains 101 open reading frames (ORFs). A majority of the ORFs code for predicted proteins that can be assigned to respective clusters of orthologous groups (COG). Their suggested functions cover diverse functional categories including genetic information storage and processing, cellular processes, and metabolism. The most notable gene cluster found in this genome segment is a super-operon capable of encoding 30 proteins, of which 26 are ribosomal proteins. The organization of the genes in this operon reflects the unique evolutionary position of the spiroplasma. A region containing gene duplications, domain rearrangements, and frameshift mutations, which are indicators of phase variation, was also identified in the genome segment. In addition to the protein-encoding capabilities, this genome segment includes two tRNA genes as well.