Comparison of the free amino acid composition in the hemolymph of healthy and Nosema-infected female honey bees

Abstract

Nineteen amino acids or related compounds were identified in the hemolymph of Nosema-infected and healthy 5- and 10-day-old worker honey bees ( Apis mellifera), and 29 free amino acids and their derivatives were identified in hemolymph from both diseased and healthy queen and worker honey bees of different ages. Phosphoethanolamine, citrulline, cystathionine, hydroxylysine, ethanolamine, and l-methylhistidine were found for the first time in honey-bee hemolymph. In general, higher amounts of amino acids were found in the hemolymph of healthy female bees than in that of infected bees. This may be an indication that the metabolic activites of Nosema-infected bees were less than those of healthy bees of the same age. Also, “hypoaminoacidemia” might result from the pathogen's “need” for amino acids. The death of the diseased females might not be the result of nutritional starvation. No pattern of amino acids was apparent in the hemolymph of either worker or queen honey bees that might indicate a nutritional balance that could be used to overcome nosema infection.