Draft Genome Sequence of Photorhabdus luminescens subsp. laumondii HP88, an Entomopathogenic Bacterium Isolated from Nematodes

Photorhabdus luminescens subsp. laumondii HP88 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 5.27-Mbp draft genome sequence for P. luminescens subsp. laumondii HP88, with a G+C content of 42.4% and containing 4,243 candidate protein-coding genes.

cent bacteria that maintain two distinct lifestyles as insect pathogens and in a symbiotic relationship with the entomopathogenic Heterorhabditis nematodes (see references 1-7 for a review). The life cycles of Photorhabdus and its nematode host Heterorhabditis are best described as a cyclic association that begins and ends with infective juvenile (IJ) nematodes. A monoculture of Photorhabdus is maintained within the anterior region of the IJ nematode's intestine (8,9). The nematodes actively seek and infect insect hosts by entering through natural openings or by burrowing directly through the insect cuticle. Once inside the insect, the nematodes regurgitate the bacteria into the hemolymph (8). The bacteria release highly virulent toxins (10,11), which results in insect death in Ͻ48 h. As the bacteria enter the stationary phase of their growth cycle, they secrete extracellular enzymes that aid in breaking down insect tissue, thereby providing nutrients for both the bacteria and nematodes. The bacteria also generate essential growth factors for the nematode growth and development. The growth and development of Heterorhabditis nematodes have an obligate requirement for their specific bacterial symbiont (12). The bacteria also release antibiotics to prevent secondary invaders and putrefaction of the insect carcass (13,14). After several days of feeding, the nematodes and bacteria reassociate and leave in search of a new insect host.
The draft genome of P. luminescens strain HP88 was generated at the Hubbard Genome Center (University of New Hampshire, Durham, NH) using Illumina technology (26) techniques. A standard Illumina shotgun library was constructed and sequenced using the Illumina HiSeq 2000 platform, which generated 7,680,248 reads (260-bp insert size) totaling 1,120.0 Mbp. The Illumina sequence data were assembled using CLC Genomics Workbench (version 8.5) and AllPaths-LG (version r41043) (27). The final draft assembly contained 287 contigs, with an N 50 of 34.4 kb. The total size of the genome is 5.27 Mbp, and the final assembly is based on 949 Mb of Illumina draft data, providing an average 163ϫ coverage of the genome.
The high-quality draft genome of P. luminescens strain HP99 was resolved to 287 contigs consisting of 5,268,230 bp, with a GϩC content of 42.4%. The assembled P. luminescens strain HP88 genome was annotated via the NCBI Prokaryotic Genome Annotation Pipeline (PGAP) and resulted in 4,243 candidate proteincoding genes.
Nucleotide sequence accession numbers. This whole-genome shotgun project has been deposited at DDBJ/EMBL/GenBank under the accession no. LJPB00000000. The version described in this paper is version LJPB01000000.

FUNDING INFORMATION
This work, including the efforts of Shimaa Ghazal, was funded by Egyptian Cultural and Education Bureau. This work, including the efforts of W. Kelley Thomas, was funded by National Science Foundation (NSF) (DBI-1229361). This work, including the efforts of Louis S. Tisa, was funded by U.S. Department of Agriculture (USDA) (NIFA 2009-35302-05257).