Potential costs of bacterial infection on storage protein gene expression and reproduction in queenless Apis mellifera worker bees on distinct dietary regimes

► We investigated the costs of bacterial infection in bees on distinct dietary regimes. ► The costs of infection were very evident in beebread-fed bees. ► Infection down-regulated transcription of genes involved in protein storage. ► Infection impaired ovary activation in queenless worker bees. ► Storage protein and reproduction destined resources may be used to support defense.