Vespa crabro and V. analis are social hornet species commonly found in Asia, including Korea. Mastoparan is one of the major venom peptides of these two hornets but its amino acid sequence defers substantially. To examine the differences in the potential toxicity and bioactivity of mastoparans between these two social hornets, differential toxicological and pharmacological activities of synthesized mastoparan were investigated. V. analis mastoparan showed a 7-fold higher hemolytic activity, suggesting its higher cytotoxic potential compared with V. crabro mastoparan. Mastoparans from both hornet species exhibited similar levels of antimicrobial activities against Staphylococcus aureus and Botrytis cinerea, whereas the mastoparan from V. analis showed more potent antimicrobial activities against Escherichia coli and Candida albicans. Nevertheless, the antimicrobial activities of mastoparans of V. crabro and V. analis were relatively lower compared with those of other wasps. Both mastoparans also exhibited some levels of antitumor activity but the activity was significantly higher in V. analis mastoparan. In summary, the hemolytic, antimicrobial, and antitumor activities of synthesized V. analis mastoparan were higher than those of V. crabro mastoparan. These differential bioactivities are likely due to the amino acid sequence differences in the mature peptides. In particular, the additional Lys residue present in V. analis mastoparan may contribute to the higher levels of bioactivity as proposed by secondary structure prediction.

The hornets Vespa crabro and V. analis are widely distributed in Asia and are known to be aggressive when disturbed, resulting in frequent stinging accidents. To investigate the differences in venom properties and toxicities between these two hornets, the transcriptomic profiles of venom glands, in conjunction with the venom components, were analyzed and compared. A total of 35 venom-specific genes were identified in both venom gland transcriptomes, but their transcriptional profiles were different between V. crabro and V. analis. In addition, the major venom components were identified and confirmed by mass spectroscopy. Prepromastoparan, vespid chemotactic precursor and vespakinin were the top three genes most prevalently transcribed in the venom gland of V. crabro, and their transcription rates were 112-, 16- and 161-fold higher, respectively, compared with those in V. analis, as judged by FPKM values. In the venom gland of V. analis, however, vespid chemotactic precursor was the most abundantly transcribed gene, followed by premastoparan and vespakinin. In general, most major venom genes were more abundantly expressed in V. crabro, whereas some minor venom genes exhibited higher transcription rates in V. analis, including muscle LIM protein, troponin, paramyosin, calponin, etc. Our findings reveal that the overall venom components of V. crabro and V. analis are similar, but that their expression profiles and levels are considerably different. The comparison of venom gland transcriptomes suggests that V. crabro likely produces venom with more highly enriched major venom components, which has potentially higher toxicity compared with V. analis venom.

Vespa crabro is a cosmopolitan social wasp species whereas Vespa analis is commonly found in Asia. Both species are widely distributed in Korea and known to be aggressive when disturbed, resulting in frequent sting accidents. Although major venom components of well known Vespa wasps have been reported, no comparative transcriptomic analysis of venom gland between V. crabro and V. analis has been conducted to date. To investigate the differences in venom properties between these two wasps, total RNA was extracted from each venom gland and used for RNA-sequencing. A total of 31 venom-specific genes were identified in both venom gland transcriptomes but their expression profiles were different between V. crabro and V. analis. Venom allergen 5, premastoparan A and phospholipase A were the top three genes that were most prevalently transcribed in the venom gland of V. crabro, and their transcription rates were 902-, 112- and 4164-fold higher compared with V. analis, respectively, as judged by FPKM values. Their differential transcription profiles were confirmed by quantitative real-time PCR. In the venom gland of V. analis, however, premastoparan A was most abundantly transcribed gene, followed by calponin and tropomysin. In general, most venom-specific genes were more abundantly expressed in V. crabro but some genes exhibited higher transcription rates in V. analis, including muscle LIM protein, troponin, paramyosin, calponin, etc. Our findings suggest that V. crabro produce venom with much more enriched venom components, thereby with higher toxicity compared with V. analis.