Type Strains of Entomopathogenic Nematode-Symbiotic Bacterium Species, Xenorhabdus szentirmaii (EMC) and X. budapestensis (EMA), Are Exceptional Sources of Non-Ribosomal Templated, Large-Target-Spectral, Thermotolerant-Antimicrobial Peptides (by Both), and Iodinin (by EMC)

Abstract

Antimicrobial multidrug resistance (MDR) is a global challenge, not only for public health, but also for sustainable agriculture. Antibiotics used in humans should be ruled out for use in veterinary or agricultural settings. Applying antimicrobial peptide (AMP) molecules, produced by soil-born organisms for protecting (soil-born) plants, seems a preferable alternative. The natural role of peptide-antimicrobials, produced by the prokaryotic partner of entomopathogenic-nematode/bacterium (EPN/EPB) symbiotic associations, is to sustain monoxenic conditions for the EPB in the gut of the semi-anabiotic infective dauer juvenile (IJ) EPN. They keep pathobiome conditions balanced for the EPN/EPB complex in polyxenic (soil, vanquished insect cadaver) niches. Xenorhabdus szentirmaii DSM16338(T) (EMC), and X. budapestensis DSM16342(T) (EMA), are the respective natural symbionts of EPN species Steinernema rarum and S. bicornutum. We identified and characterized both of these 15 years ago. The functional annotation of the draft genome of EMC revealed 71 genes encoding non-ribosomal peptide synthases, and polyketide synthases. The large spatial Xenorhabdus AMP (fabclavine), was discovered in EMA, and its biosynthetic pathway in EMC. The AMPs produced by EMA and EMC are promising candidates for controlling MDR prokaryotic and eukaryotic pathogens (bacteria, oomycetes, fungi, protozoa). EMC releases large quantity of iodinin (1,6-dihydroxyphenazine 5,10-dioxide) in a water-soluble form into the media, where it condenses to form spectacular water-insoluble, macroscopic crystals. This review evaluates the scientific impact of international research on EMA and EMC.

Identification and environment-friendly biocontrol potential of five different bacteria against Aphis punicae and Aphis illinoisensis (Hemiptera: Aphididae)

“…This protein’s impact on the pea aphid Acyrthosiphon pisum was also investigated ( Zeng et al, 2012 ; Jin et al, 2014 ). Xenorhabdus szentirmaii is a one-of-a-kind source of antimicrobial peptides that are effective against virtually all known phytopathogens ( Fuchs et al, 2014 ; Fodor et al, 2022 ).…”

XENOFOOD - An Autoclaved Feed Supplement Containing Autoclavable Antimicrobial Peptides - Exerts Anticoccidial GI Activity, and Causes Bursa Enlargement, But Has No Detectable Harmful Effects In Broiler Cockerels Despite <em>In Vitro</em> Cytotoxic Ingredients

“…AMPs comprise a potentially promising toolkit combatting MDR because antibioticresistant bacteria perform a high frequency of collateral sensitivity to antimicrobial peptides, [13], [16][17]. X. budapestensis (EMA) and X. szentirmaii (EMC) are abundant sources of NR-AMP molecules of large target spectra and strong anti-pathogen potential, [35]. Each NR-AMP molecule in the Xenorhabdus CFCM is the end-product of a biosynthetic pathway.…”

“…The respective methods have been published in [39]. These antibiotic-producing bacteria were freshly taken from frozen cultures and grown on the bacterial species grown on MacConkey agar plates before they were transferred to the liquid medium as described before, [35][36][37][38][39][40]. The bacterial species were grown on MacConkey agar plates before they were transferred to the liquid medium, and unexpectedly two different types of colonies for TT01 were observed on the agar plates: red-brown colored colonies which adsorbed the neutral red from the MacConkey agar and yellow-colored colonies which did not so.…”

“…These bacteria are considered potential sources of potent natural anti-microbial [31], and anti-protist [33] compounds. We have previously found antimicrobial active secreted peptides produce by Xenorhabdus budapestensis and X. szentirmaii [34], [35] in both solid, and liquid media that were active against [HM1] [u2] Grampositive and -negative pathogenic bacteria, [34], [36]; anti-plant pathogenic bacterial [37-38], anticoccidial [39], anti-oomycetes [37], [40], as well as antifungal (Ujszegi et al, in preparation) activity.…”

“…Clostridium perfringens LH1-LH8; LH11-LH16; LH19, and LH20 are of chicken origin, and LH24 came from a pig; each has been deposited in the (frozen) stock collection of the Department of Microbiology and Infectious Diseases, University of Veterinary Medicine Budapest, Hungary. Xenorhabdus strains, X. budapestensis DSM 16342(T) (Lengyel) (EMA), and X. szentirmaii DSM 16338 (T) (Lengyel)(EMC)[34][35]. of EMA and EMC CFCM bioassays were tested on different Gram-positive strains including Clostridium perfringens strains were carried out as described before, [35-39]..In vitro experiments: 10% heat-inactivated fetal bovine serum FBS (Invitrogen/GIBCO), penicillin G (200 IU/ml) and streptomycin (200 µg/ml), respectively.In detail, cells were inoculated into 25 cm (2) flasks with filtered caps (Sarstedt) containing an end volume of 7 ml culture and incubated in a controlled atmosphere of…”