Draft Genome Sequence of Micromonospora sp. Strain MW-13, a Bacterial Strain with Antibacterial Properties and Plant Growth Promotion Potential Isolated from the Rhizosphere of Wheat in Iran.

Jahanshah G, Miess H, Busche T, et al. Draft Genome Sequence of Micromonospora sp. Strain MW-13, a Bacterial Strain with Antibacterial Properties and Plant Growth Promotion Potential Isolated from the Rhizosphere of Wheat in Iran. Microbiology resource announcements. 2019;8(2): e01375-18

Feasibility of Heavy Metals Removal from Compost by Biosurfactant

Biosurfactants have the ability to form heavy metal complexes and clean up heavy metal contaminated soils. In this work, a biosurfactant producing bacterium (Bacillus spp.) isolated from compost and Pseudomonas aeuroginosa ATCC3027 were cultured in whey in order to produce biosurfactant. Compost samples were leached by supernatant of mentioned strains. Total amount of Pb, Ni, Cr, Cd, Zn, Cu and Mn in samples were measured before and after treatment was measured. It was revealed that supernatant of P. aeuroginosa ATCC 3027 removed 52, 49, 60, 33, 25, 32 and 22% of Pb, Ni, Cr, Cd, Zn, Cu and Mn respectively. Heavy metal removal by supernatant of strain B was 45, 39, 42, 33, 40, 41 and 29% for above mentioned metals; respectively. These results indicate the potential of the biosurfactants as leaching agents for heavy metal removal from compost

Methods for the comprehensive structural elucidation of constitution and stereochemistry of lipopeptides

A panel of methods of general suitability for complete structural elucidation of the stereochemistry of cyclopeptides, depsipeptides and lipopeptides is presented and described in detail. The suitability of the proposed methods was exemplified on the lipopeptide poaeamide from Pseudomonas poae. Amino acid configurations have been assigned by direct LC enantiomer separation with Chiralpak ZWIX(+) and were confirmed by GC enantiomer separation on Chirasil L-Val. 3-Hydroxydecanoic acid absolute configuration was analyzed on Chiralpak ZWIX(+) and confirmed by injection on ZWIX(-) which showed opposite elution order. Plenty of D-amino acids have been found in this lipopeptide. It contained in total 5 Leu residues of which one had n-configuration. The position of the D-Leu in the peptide sequence was determined by pepsin and chemical digestions in combination with isolation of diagnostic peptide-fragments and subsequent identification of absolute configurations of the Leu residues. This allowed pinpointing the position of the D-amino acid. The complementarity of the peptide retention profiles on Chiralpak ZWIX column as compared to both RPLC and HILIC suggests its great utility as an alternative peptide separation tool. (C) 2015 Elsevier B.V. All rights reserved

The novel lipopeptide Poaeamide of the endophyte Pseudomonas poae RE*1-1-14 is involved in pathogen suppression and root colonization

Endophytic Pseudomonas poae strain RE*1-1-14 was originally isolated from internal root tissue of sugar beet plants and shown to suppress growth of the fungal pathogen Rhizoctonia solani both in vitro and in the field. To identify genes involved in its biocontrol activity, RE*1-1-14 random mutagenesis and sequencing led to the identification of a nonribosomal peptide synthetase (NRPS) gene cluster predicted to encode a lipopeptide (LP) with a 10-amino acid peptide moiety. The two unlinked gene clusters consisted of three NRPS genes, designated poaA (cluster 1), and poaB and poaC (cluster 2), spanning approximately 33.7 kb. In silico analysis followed by chemical analyses revealed that the encoded LP designated poaeamide, is a structurally new member of the orfamide family. Poaeamide inhibited mycelial growth of R. solani and different oomycetes including Phytophthora capsici, Ph. infestans, and Pythium ultimum. The novel LP was shown to be essential for swarming motility of strain RE*1-1-14 and had an impact on root colonization of sugar beet seedlings The poaeamide-deficient mutant colonized the rhizosphere and upper plant cortex at higher densities and with more scattered colonization patterns than the wildtype. Collectively these results indicate that P. poae RE*1-1-14 produces a structurally new LP that is relevant for its antagonistic activity against soil-borne plant pathogens and for colonization of sugar beet roots