Multi-functionPlantDefensin,AntimicrobialandHeavyMetal Adsorbent Peptide.

BACKGROUND

Defensin peptide isolated from plants are often heterogeneous in length, sequence and structure, but they are mostly small, cationic and amphipathic. Plant defensins exhibit broad-spectrum antibacterial and antifungal activities against Gram-positive and Gram-negative bacteria, fungi and etc. Plant defensins also play an important role in innate immunity, such as heavy metal and some abiotic stresses tolerance.

OBJECTIVES

In this paper, broad-spectrum activities, antimicrobial and heavy metal absorption, of a recombinant plant defensin were studied.

MATERIAL AND METHODS

gene, a modified plant defensin gene, was cloned in pBISN1-IN (EU886197) plasmid, recombinant protein was produced by transient expression via Agroinfiltration method in common bean. The recombinant protein was tested for antibacterial activity against Gram-negative, Gram-positive bacteria and Fusarium sp. the effects of different treatments on heavy metal zinc absorption by this peptide were tested.

RESULTS

We confirmed the antibacterial activities of this peptide against Gram-negative ( and ) and Gram-positive ( and ) bacteria, and antifungal activities of this peptide against Fusarium spp. ( and ). High metal absorption coefficient for this peptide was also observed.

RESULTS

Out of six actinobacterial isolates, VITVAMB 1 possessed the most efficient RO-16 decolorization property. It decolorized 85.6% of RO-16 (250 mg L) within 24hrs. Isolate VITVAMB 1 was identified to be sp. Maximum dye decolorization occurred at pH 8, temperature 35oC, 3% salt concentration and a dye concentration of 50 mg L.

CONCLUSIONS

Results suggesting that modified defensin peptide facilitates a broader range of defense activities. dedefensins are an important part of the innate immune system in eukaryotes. These molecules have multidimensional properties that making them promising agents for therapeutic drugs.