Antibiotic production in relation to bacterial growth and nematode development in Photorhabdus--Heterorhabditis infected Galleria mellonella larvae.
The population of Photorhabdus luminescens C9, bacterial symbiont of the entomopathogenic nematode, Heterorhabditis megidis 90, increased rapidly to 1.2-2.6x10(9) cells g(-1) wet Galleria mellonella larvae within 24 h of nematode infection of the larvae, and maintained a relatively constant level (1.2-2.0x10(10) cells g(-1)) through the entire 14-day period of nematode development. The antibiotic, 3, 5-dihydroxy-4-isopropylstilbene, was produced by P. luminescens C9 after 24 h of nematode infection, increased rapidly at 2-5 days postinfection and remained at a level of 3000-3600 microg g(-1) wet larvae until about 21 days, decreasing gradually thereafter. The early production and continued presence of a relatively large amount of 3,5-dihydroxy-4-isopropylstilbene in the infected insect supports the hypothesis that the antibiotics produced by the bacterial symbiont help minimize competition from other microorganisms and prevents the putrefaction of the nematode-infected insect cadaver.
Hu
K
K
Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Vancouver, Canada V5A 1S6. kaija@sfu.ca
Webster
J M
JM
D000818:Animals; D000935:Antifungal Agents / Q000378:metabolism*; D007313:Insecta / Q000382:microbiology* / Q000469:parasitology*; D009348:Nematoda / Q000254:growth & development*; D020637:Photorhabdus / Q000378:metabolism*; D012118:Resorcinols / Q000378:metabolism; D013267:Stilbenes / Q000378:metabolism; D013559:Symbiosis
D000935:Antifungal Agents; D012118:Resorcinols; D013267:Stilbenes; C571829:tapinarof