서양종 꿀벌(Apis mellifera L.)의 봉독은 예로부터 항염증과 탁월한 진통 효과로 인해 많은 질병 치료에 이용되어 왔다. 이러한 기능성은 멜리틴과 같은 봉독의 다양한 활성물질로부터 기인하며 약리기전에 대한 연구도 활발하다. 그러나 아직까지 봉독 내에 존재하는 생체아민에 대한 연구는 미흡하다. 본 연구에서는 초고성능액체크로마토그래피를 이용하여 봉독 내에 존재하는 생체아민인 putrescine의 존재 여부를 확인하였으며 이에 대한 밸리데이션을 수행하였다. 밸리데이션은 특이성, 정확성 및 정밀도를 평가하고 분석법을 검증하였다. Putrescine 분석의 선형성은 R≥0.99로 높은 선형성을 나타냈으며, 검출한계는 0.9 μg/ml, 정량한계는 2.7 μg/ml였으며, 회수율은 96.4%-99.9%로 나타났다. Intra-day 정밀도와 inter-day 정밀도의 상대표준편차(RSD) 값은 각각 0.16%-0.23%와 0.09%-0.36%였으며, 이는 RSD 값이 5%이하의 우수한 정밀도 를 보였다. 따라서 본 분석법은 putrescine 분석에 있어서 선형성, 검출한계, 정량한계 및 회수율을 모두 만족하는 것으로 확인되었다. 또한 봉독 내에 존재하는 putrescine의 함량을 조사해본 결과 3.1 ± 0.09 mg/g 존재하였으며 본 연구를 통해 봉독 내 putrescine 함량에 대한 기본적인 데이터를 제공하며, 이는 다양한 생물 활성에 대한 추가 연구에 유용할 것으로 사료된다.
Honeybee (Apis mellifera) egg-yolk protein vitellogenin (Vg) plays roles in immunity, antioxidation, and life span beyond reproduction, but it also acts as an allergen Api m 12 in venom. Here we established antimicrobial and antioxidant roles of honeybee Vg in the body and venom. Using the cDNA encoding Vg identified from Asiatic honeybee (A. cerana) workers, recombinant A. cerana Vg (AcVg) protein of approximately 180 kDa was produced in baculovirus-infected insect cells. In A. cerana worker bees, AcVg was expressed in the fat body and venom gland and was present in the secreted venom. AcVg induced structural damage in microbial cell walls via binding to microbial surfaces and exhibited antimicrobial activity against bacteria and fungi. AcVg protected mammalian and insect cells against oxidative damage through direct shielding of cell membranes. Interestingly, AcVg exhibited DNA protection activity against reactive oxygen species (ROS). Furthermore, the transcript level of AcVg was upregulated in the fat body, but not in the venom gland, of worker bees with antimicrobial peptides and antioxidant enzymes in response to microbial infection and oxidative stress. Our data indicate that AcVg is involved in innate immunity upon infection and in a defense system against ROS, supporting a crucial role of honeybee Vg as an antimicrobial and antioxidant agent in the body and venom.
Bee venom contains a variety of peptide constituents, including low-molecular-weight protease inhibitors. While the putativelow-molecular-weight serine protease inhibitor Api m 6 containing a trypsin inhibitor-like cysteine-rich domain was identifiedfrom honeybee (Apis mellifera) venom, no anti-fibrinolytic or anti-microbial roles for this inhibitor have been elucidated.In this study, we identified an Asiatic honeybee (A. cerana) venom serine protease inhibitor (AcVSPI) that was shownto act as a microbial serine protease inhibitor and plasmin inhibitor. AcVSPI was found to consist of a trypsin inhibitor-likedomain that displays ten cysteine residues. Interestingly, the AcVSPI peptide sequence exhibited high similarity to the putativelow-molecular-weight serine protease inhibitor Api m 6, which suggests that AcVSPI is an allergen Api m 6-like peptide.Recombinant AcVSPI was expressed in baculovirus-infected insect cells, and it demonstrated inhibitory activity against trypsin,but not chymotrypsin. Additionally, AcVSPI has inhibitory effects against plasmin and microbial serine proteases; however,it does not have any detectable inhibitory effects on thrombin or elastase. Consistent with these inhibitory effects, AcVSPIinhibited the plasmin-mediated degradation of fibrin to fibrin degradation products. AcVSPI also bound to bacterial andfungal surfaces and exhibited anti-microbial activity against fungi as well as gram-positive and gram-negative bacteria. Thesefindings demonstrate the anti-fibrinolytic and anti-microbial roles of AcVSPI as a serine protease inhibitor.
Insect-derived Kazal-type serine protease inhibitors exhibit thrombin, elastase, plasmin, proteinase K, or subtilisin A inhibition activity, but so far, no functional roles for bee-derived Kazal-type serine protease inhibitors have been identified. In this study, a bee (Apis cerana) venom Kazal-type serine protease inhibitor (AcKTSPI) that acts as a microbial serine protease inhibitor was identified. AcKTSPI contained a single Kazal domain that displayed six conserved cysteine residues and a P1 threonine residue. AcKTSPI was expressed in the venom gland and was present as a 10-kDa peptide in bee venom. Recombinant AcKTSPI Kazal domain (AcKTSPI-Kd) expressed in baculovirus-infected insect cells demonstrated inhibitory activity against subtilisin A (Ki 67.03 nM) and proteinase K (Ki 91.53 nM), but not against α-chymotrypsin or typsin, which implies a role for AcKTSPI as a microbial serine protease inhibitor. However, AcKTSPI-Kd exhibited no detectable inhibitory effects on factor Xa, thrombin, tissue plasminogen activator, or elastase. Additionally, AcKTSPI-Kd bound directly to Bacillus subtilis, B. thuringiensis, Beauveria bassiana, and Fusarium graminearum but not to Escherichia coli. Consistent with these findings, AcKTSPI-Kd showed antibacterial activity against Gram-positive bacteria and antifungal activity against both plant-pathogenic and entomopathogenic fungi. These findings constitute molecular evidence that AcKTSPI acts as an inhibitor of microbial serine proteases. This paper provides a novel view of the antimicrobial functions of a bee venom Kazal-type serine protease inhibitor.
Since the ancient times the therapeutic application of honeybee venom (BV) is practised and persisted until the present days. Resistant bacteria are in emergence and some drugs no longer have an antimicrobial action. To purify the melittin known as antibacterial peptide, five major peptidergic subfractions were separated, purified and identified from the whole BV. We investigated the antibacterial activity of whole BV and purified melittin against Staphylococcus aureus by the minimum inhibitory concentrations (MIC) and the postantibiotic effect (PAE). The MIC of whole BV for S. aureus was 0.06 ㎍/㎖, respectively. The MIC of melittin was 0.06 ㎍/㎖ on S. aureus. The in vitro PAE of whole BV and isolated melittin were determined using E. coli and S. aureus. The PAE of whole BV against S. aureus were 3.45 h (1×MIC). The PAE of melittin against S. aureus was 4.35 h (1 × MIC). Also both whole BV and melittin killed S. aureus at 5 × MIC. The regrowth wasn't observed after 18 h. These results suggest that whole BV and melittin will be developed a novel antibacterial drug.