Common bed bugs can biosynthesize pheromone components from amino acid precursors in human blood

Abstract

We have recently shown that the aggregation pheromone of the common bed bug, Cimex lectularius, comprises a six-component blend of dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), (E)-2-hexenal, (E)-2-octenal, 2-hexanone, and histamine. Here, we tested the hypothesis that bed bugs biosynthesize some pheromone components from amino acid precursors in human blood, namely DMDS and DMTS from L-methionine and histamine from histidine. We tested this hypothesis by (i) allowing bed bugs to feed on and metabolize sheep blood enriched with 13C-labelled histidine or 2H-labelled methionine, (ii) extracting bed bug feces (a source of the aggregation pheromone), and (iii) analyzing feces extracts by GC-MS, HPLC-MS and NMR spectroscopy. The analyses revealed that bed bugs converted 2H-methionine to 2H-DMDS and 2H-DMTS, and 13C-histidine to 13C-histamine. There is not enough histidine in human blood to account for the amount of histamine that bed bugs produce and excrete with their feces, and only a small proportion of the available 13C-histidine was converted to 13C-histamine in our study. Therefore, it is likely that bed bugs biosynthesize histamine, and possibly also DMDS and DMTS, primarily de novo.

Sex differences in bedbug nymphs, Cimex lectularius

“…Such efforts include research that requires the laboratory breeding of thousands of animals not only for testing insecticides and critical temperatures (e.g. Ashbrook, Scharf, Bennett, & Gondhalekar, 2017, 2019; Gaire, Scharf, & Gondhalekar, 2019; Puckett, McDonald, & Gold, 2013; Romero, Potter, Potter, & Haynes, 2007), reviewed by Hase, 1930; Usinger, 1966; Feldlaufer, O'Connor, & Ulrich, 2018) but also for screening for novel control targets such as symbionts (Balvín, Roth, Talbot, & Reinhardt, 2018; Goodman, 2018), neuropeptides (Predel, Neupert, Derst, Reinhardt, & Wegener, 2018) or communication molecules (Gries, Zhai, Lewis, Britton, & Gries, 2018). All these targets are closely linked to the two major aspects that alter bedbug physiology, feeding and mating.…”

Histamine as an emergent indoor contaminant: Accumulation and persistence in bed bug infested homes

“…Histamine was recently identified as a close-range aggregation pheromone component in bed bug feces [ 24 ], with bed bugs likely synthesizing a majority of histamine de novo [ 25 ]. Histamine is a known food contaminant, mainly of fish and alcoholic beverages such as beer and wine [ 26 ].…”

Characterization and Application of a Histamine Aptamer-Based Biosensor

“…Bed bugs tend to cluster together in groups as a result of bed bug discharge of pheromones in their feces. Bed bugs release pheromones as soon as they identify safe shelters and a nearby food source, resulting in their occupation upon a surface as shown in hexenal, (E)-2-octenal, 2-hexanone, and less volatile histamine component [7,8]. Studies have shown that bed bugs biosynthesize some pheromone components such as DMDS, DMTS, and histamine from amino acid precursors in human blood, namely DMDS and DMTS from methionine and histamine from histidine [8].…”

“…Bed bugs release pheromones as soon as they identify safe shelters and a nearby food source, resulting in their occupation upon a surface as shown in hexenal, (E)-2-octenal, 2-hexanone, and less volatile histamine component [7,8]. Studies have shown that bed bugs biosynthesize some pheromone components such as DMDS, DMTS, and histamine from amino acid precursors in human blood, namely DMDS and DMTS from methionine and histamine from histidine [8]. However, studies show that there are not enough precursors such as histidine in the blood to account for the high concentration of histamine that bed bugs excrete in their feces.…”

“…However, studies show that there are not enough precursors such as histidine in the blood to account for the high concentration of histamine that bed bugs excrete in their feces. It is therefore suggested that histamine, as well as other components are primarily biosynthesized de novo [8]. Histamine excreted in feces persist in household dust whereby environmental conditions such as sanitation, temperature, and humidity can influence its persistence [5].…”