Serratia entomophila

Definition

A Gram-negative, rod-shaped bacterium in the family Enterobacteriaceae that causes amber disease, a fatal condition of scarab beetle larvae (Coleoptera: Scarabaeidae). The pathogen colonizes the gut of susceptible hosts, producing toxins that inhibit feeding and cause characteristic amber coloration of the gut contents prior to death. First isolated from the New Zealand grass grub Costelytra zealandica, it has been developed as a microbial biocontrol agent for pasture pests.

Etymology

New Latin: Serratia (honoring Italian physicist Serafino Serrati) + entomophila (Greek entomon 'insect' + philos 'loving'), referring to its insect-pathogenic lifestyle

Example

Serratia entomophila strain A1T was developed commercially as the bioinsecticide Invade® for controlling grass grub populations in New Zealand pastures, where infected larvae cease feeding within 2–5 days and die 1–3 weeks post-infection.

Related Terms

• amber disease
• Costelytra zealandica
• microbial biocontrol
• entomopathogenic bacteria
• Scarabaeidae
• itaconate

Usage Notes

Distinguished from other Serratia species by its specific pathogenicity to scarab larvae and ability to catabolize itaconate. Not all Serratia species are entomopathogenic; S. marcescens, for example, is primarily an opportunistic pathogen of humans. The specific epithet is sometimes misspelled 'entomophila' in older literature. Strain A1T (= DSM 12332T) is the type and active ingredient in registered biocontrol products.