Journal of Bioequivalence & Bioavailability

Comparative analysis, target specificities and plant protection potential of antimicrobial peptides isolated from Xenorhabdus species

6^th World Congress on Bioavailability & Bioequivalence: BA/BE Studies Summit

August 17-19, 2015 Chicago, USA

Andras Fodor1, Jerald Ensign1, Amanda Gevens1, David Vozik2 and Steven Forst3

Scientific Tracks Abstracts: J Bioequiv Availab

Abstract:

Research conception: Xenorhabdus species entomopathogenic nematode-symbiotic bacteria produce NRP (non-ribosomal peptides)
antimicrobial peptides to protect the monoxenic nematode-bacterium symbiotic complex in soil condition. The HPLC and MALDI
analysis show that the profiles of the different species are not the same. We supposed that the target specificities of the different
peptides are different, even if there must be some overlaps.
Aim: We determined the target specificities of MALDI fractions of the antimicrobial peptide-rich fractions (APF) uniformly prepared
from antibiotics-producing strains.
Method: We prepared antibiotic peptide fractions (APF) from X. budapestensis AF13, X. marinarium HGB2199, X. szentimaii
HGB0836, X. bovienii HGB2185 and X. nematophila ATTC61019. We compared the HPLC and MALDI profile and also the
antimicrobial activities of the different fractions against Gram positive (S. aureus) and Gram negative (E. coli, Agrobacterium
tumefaciens) bacteria; fungi (Candida) and Oomycete (Phytophthora infestans).
Results: We discovered antibiotic peptides active against (i) only Gram positive bacteria; (ii) Gram-positive, Gram-negative; oomycete
and fungal target. The identification of the molecules is on the way. The plant protection potential of X. budapestensis is demonstrated
by in vitro and in planta experiments on fire-blight infested apple flowers.
Significance: The spreading multidrug resistance occurring in both prokaryotic and eukaryotic pathogens urge the researchers to
find new compound of strong antimicrobial potential and of novel mechanisms of action The Xenorhabdus species used this study
are a golden mine of such compounds.

Biography :

Andras Fodor has completed his PhD from Eotvos University of Budapest, Hungary. He is a Visiting Research Professor (a Fulbright Research Grantee) at the Department
of Bacteriology of the University of Wisconsin-Madison. The research team is focusing on antimicrobial peptides of entomo-pathogenic nematode symbiotic bacteria. He
has published more than 40 papers in reputed journals.