E detrimental effects of inhibitors on insects have been effectively documented. The adverse effect of cysteine PIs around the development of specific coleopteran species was shown years ago (Orr et al. 1994). The L. decemlineata uses cysteine and aspartyl proteases (Michaud et al. 1993). Asdemonstrated applying the synthetic inhibitor E-64 (transepoxysuccinyl-L-leucylamido(4-guanidino)butane), cysteine PIs considerably inhibit L. decemlineata larvae growth (Wolfson and Murdock 1987). In addition, cysteine PIs happen to be shown to impact the protease activity of coleopteran larvae, for example these of D. undecimpunctata howardi (Fabrick et al. 2002) or the D. virgifera virgifera (Zhao et al. 1996). Frequently, pests have evolved distinct adaptations to minimize the dangerous activities of PIs. They may enhance digestive enzyme activity, synthesize much more resistant proteases (Paulillo et al. 2000), digest inhibitors within the gut (Girard et al. 1998), decrease the sensitivity of their enzymes to inhibitors (Brito et al. 2001). For instance, proteases of Z. subfasciatus are capable of degrading an aAI in the prevalent bean (Ishimoto et al. 1996). The soybean cysteine PI soyacystatin N (scN) is capable of suppressing the digestive enzymes of herbivorous insects and may inhibit the growth and development of C. maculatus, L. decemlineata, and D. virgifera virgifera (Zhao et al. 1996; Koiwa et al. 1997; Zhu-Salzman et al. 2003). C. maculatus has evolved counter-defensive strategies against scN, such as increasing the expression of scN-sensitive and scN-insensitive enzymes and hydrolyzing scN (Zhu-Salzman et al. 2003). Oppert et al. (2004) reported that T. castaneum larvae have evolved mechanisms to overcome dietary inhibitors. While larvae of this pest generate cysteine and serine proteases, cysteine proteases will be the main digestive proteases. Serine and cysteine PIs alone had minimal effects on larvae improvement and protease activity since the digestive preferences were switched from cysteine protease-based to serine protease-based digestion. Larval growth was inhibited when both cysteine and serine PIs have been present. Furthermore, Zhu-Salzman et al. (2003) indicated that T. castaneum responds to cysteine PIs by increasing the production of aspartic proteases. Even so, the L. decemlineata responded to cathepsin D inhibitors in SCH00013 site transgenic plants by decreasing the production of inhibitor-sensitive enzymes (Brunelle et al. 2004). Further, in Oulema spp. larvae that PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/20047908 were fed the synthetic serine PI AEBSF (4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride), two additional protease activities had been observed (Wielkopolan et al. 2015). Interestingly beetles might also use proteases of endosymbiotic bacteria inhabiting their gut, what can lead to the alter of insect’s food preferences (adaptation of insect to a new host plants) (Chu et al. 2013; Shao et al. 2012). For instance, within this way D. virgifera virgifera adapted to feeding around the non-host plants, like soybean (Glycine max), which was introduced in to the corn field for crop rotation (Chu et al. 2013). Presented examples of beetles adaptation to inhibitory or toxic plant compounds showed that when the insects have been exposed to one class of PIs, they shift for the production of aPlanta (2016) 244:313different class of proteases. When more than one particular class of PIs was present, then the larvae have been unable to adapt making use of an additional class of proteases. As mentioned above insects digestive system isn’t passive but flexible. Prof.