**4. Conclusions**

Recent studies have highlighted the importance of the melittin as a natural drug for different applications, due to its anti-inflammatory, anti-mutagenic, contraceptive, antimicrobial, and even an anticancer effect. Its mass production is, therefore, of great pharmacological interest and, due to this, obtaining bacteria genetically transformed with this gene becomes very desirable. In other studies, melittin cDNA has been inserted into different plasmids: pBR322 [25], pBV220 [26], and pUC118 [27]. Recently, a gene encoding a hybrid peptide with melittin, called LfcinB (1–15)-Melittin (5–12), has been inserted into the pET-32a vector [28]. In addition, in other study, *E. coli* has been transformed with melittin cDNA from *Apis cerana* [4]. In this work, melittin cDNA from *A. mellifera* has been inserted in *E. coli* using the pGEM-T vector. So, its identification and genetic cloning system have been demonstrated, for its 3'T overhangs at the insertion site, proving a binding successful. Furthermore, the mentioned vector has T7 and SP6 RNA promotors that will ensure its expression in the *E. coli* cells used. Also, another study worked with this vector system [4], suggesting the best way for cloning with these kinds of vectors.

However, it must be remembered that in order to obtain melittin in *E. coli* as a final product, the immature peptide prepromelittin should be posttranslationally modified in some steps. In the first step, the enzyme that catalyzes the hydrolysis of prepromelittin to promilittin is supposed to be widely distributed, since prepromellitin has never been obtained in a cell system. Moreover, promelittin has been obtained in venom glands of honeybees fed with radioactive amino acids [9] and in frog oocytes injected with this mRNA from queen bee [29], but melittin has never been obtained in any tissue that does not come from a species of the genus *Apis*.

For all these reasons, it may be thought the other studies that have cloned melittin cDNA in cell systems that do not belong to species of the genus *Apis*, are likely to give rise to the obtaining of promelittin as a final product, as is the case of the present study. It is necessary to clarify which is the final peptide that has been obtained. If promelittin has been finally obtained, the next focus of study could be to design a protocol to convert it to melittin into *E. coli*.
