Pyoverdine and histicorrugatin-mediated iron acquisition in Pseudomonas thivervalensis.

The genome of Pseudomonas thivervalensis LMG 21626(T) has been sequenced and a genomic, genetic and structural analysis of the siderophore mediated iron acquisition was undertaken. Pseudomonas thivervalensis produces two structurally new siderophores, pyoverdine PYOthi which is typical for P. thivervalensis strains and a closely related strain, and the lipopeptidic siderophore histicorrugatin which is also detected in P.

New linear lipopeptides produced by Pseudomonas cichorii SF1-54 are involved in virulence, swarming motility, and biofilm formation.

Pseudomonas cichorii is the causal agent of lettuce midrib rot, characterized by a dark-brown to green-black discoloration of the midrib. Formation of necrotic lesions by several plant-pathogenic pseudomonads is associated with production of phytotoxic lipopeptides, which contribute to virulence. Therefore, the ability of P.

Biosynthesis of the pyoverdine siderophore of Pseudomonas aeruginosa involves precursors with a myristic or a myristoleic acid chain.

Pyoverdine I (PVDI) is the major siderophore produced by Pseudomonas aeruginosa to import iron. Biosynthesis of this chelator involves non-ribosomal peptide synthetases and other enzymes. PvdQ is a periplasmic enzyme from the NTN hydrolase family and is involved in the final steps of PVDI biosynthesis.

Siderophore-mediated iron acquisition in the entomopathogenic bacterium Pseudomonas entomophila L48 and its close relative Pseudomonas putida KT2440.

Pseudomonas entomophila L48 is a recently identified entomopathogenic bacterium which, upon ingestion, kills Drosophila melanogaster, and is closely related to P. putida. The complete genome of this species has been sequenced and therefore a genomic, genetic and structural analysis of the siderophore-mediated iron acquisition was undertaken.

Collision-induced loss of AgH from Ag+ adducts of alkylamines, aminocarboxylic acids and alkyl benzyl ethers leads exclusively to thermodynamically favored product ions.

The loss of AgH from [M+Ag]+ precursor ions of tertiary amines, aminocarboxylic acids and aryl alkyl ethers is examined by deuterium labeling combined with collision activation (CA) dissociation experiments. It was possible to demonstrate that the AgH loss process is highly selective toward the hydride abstraction. For tertiary amines and aminocarboxylic acids, hydrogen originates from the alpha-methylene group carrying the nitrogen function (formation of an immonium ion).

Ornicorrugatin, a new siderophore from Pseudomonas fluorescens AF76.

From a pyoverdin-negative mutant of Pseudomonas fluorescens AF76 a new lipopeptidic siderophore (ornicorrugatin) could be isolated. It is structurally related to the siderophore of Pseudomonas corrugata differing in the replacement of one Dab unit by Orn.

Genomic, genetic and structural analysis of pyoverdine-mediated iron acquisition in the plant growth-promoting bacterium Pseudomonas fluorescens SBW25.

Background: Pyoverdines (PVDs) are high affinity siderophores, for which the molecular mechanisms of biosynthesis, uptake and regulation have been extensively studied in Pseudomonas aeruginosa PAO1. However, the extent to which this regulatory model applies to other pseudomonads is unknown. Here, we describe the results of a genomic, genetic and structural analysis of pyoverdine-mediated iron uptake by the plant growth-promoting bacterium P.

Structural analysis of linear hydroxyproline-bound O-glycans of Chlamydomonas reinhardtii--conservation of the inner core in Chlamydomonas and land plants.

Linear hydroxyproline-bound O-glycans of the unicellular green alga Chlamydomonas reinhardtii were isolated from outer cell wall glycoproteins and their structure elucidated by chemical and spectroscopic methods. They consist exclusively of arabinose and galactose, the latter in the furanose form, unusual for plants. The first two arabinoses linked to hydroxyproline have the same anomeric configuration and linkage to each other as do the arabinosides isolated from land plants, suggesting that these two steps of hydroxyproline-O-glycosylation have been conserved during evolution.

Siderotyping of fluorescent Pseudomonas: molecular mass determination by mass spectrometry as a powerful pyoverdine siderotyping method.

The numerous pyoverdines so far characterized as siderophores of fluorescent Pseudomonas could be usually differentiated one from each others by the two physico-chemical and physiological methods of siderotyping, i.e., siderophore-isoelectrofocusing and siderophore-mediated iron uptake.

Curium(III) complexation with pyoverdins secreted by a groundwater strain of Pseudomonas fluorescens.

Pyoverdins, bacterial siderophores produced by ubiquitous fluorescent Pseudomonas species, have great potential to bind and thus transport actinides in the environment. Therefore, the influence of pyoverdins secreted by microbes on the migration processes of actinides must be taken into account in strategies for the risk assessment of potential nuclear waste disposal sites. The unknown interaction between curium(III) and the pyoverdins released by Pseudomonas fluorescens (CCUG 32456) isolated from the granitic rock aquifers at the Aspö Hard Rock Laboratory (Aspö HRL), Sweden, is the subject of this paper.

Amino acids, iron, and growth rate as key factors influencing production of the Pseudomonas putida BTP1 benzylamine derivative involved in systemic resistance induction in different plants.

The biological control bacterium Pseudomonas putida BTP1 exerts its protective effect mostly by inducing an enhanced state of resistance in the host plant against pathogen attack [induced systemic resistance (ISR)]. We previously reported that a specific compound derived from benzylamine may be involved in the elicitation of the ISR phenomenon by this Pseudomonas strain. In this article, we provide further information about the N,N-dimethyl-N-tetradecyl-N-benzylammonium structure of this determinant for ISR and show that the benzylamine moiety may be important for perception of the molecule by root cells of different plant species.

Structure proposal for a new pyoverdin from Pseudomonas sp. PS 6.10.

From Pseudomonas sp. PS 6.10, when grown in a casamino acid medium, a pyoverdin was isolated whose primary structure could be deduced from its mass spectrometric fragmentation pattern and amino acid analysis.

Characterization of the chromophores of pyoverdins and related siderophores by electrospray tandem mass spectrometry.

Characteristic fragment ions of the various chromophores of the pyoverdin siderophore family obtained by collision activated dissociation of the [M+2H]2+ ions are reported allowing unambiguous identification. Tandem mass spectrometrical studies revealed the existence of the first example of a ferribactin with a succinamide side chain, and they add some information to the problem in which way a malic acid side chain is attached to the chromophore.

Structure elucidation of cyclic pyoverdins and examination of rearrangement reactions in MS/MS experiments by determination of exact product ion masses.

Structure elucidation of naturally occurring linear and cyclic peptidic compounds can be complicated by rearrangement reactions induced upon collision activation (CA) when parts of the molecule migrate, suggesting incorrect substitution patterns. Such complex rearrangements are examined and discussed for two iron complexing compounds produced by the bacterial genus Pseudomonas (so-called pyoverdins). Various MS2- and MS3-product ion experiments were performed using a quadrupole-ion trap (QIT) at low resolution and a FT-ICR at high resolution allowing accurate mass determinations.

The X-ray structure of the pyochelin Fe3+ complex.

By X-ray structure analysis it could be shown that from the solution equilibrium of pyochelin I and II, differing in the stereochemistry at C-2" (1a and 1b), crystals of the Fe3+ complex of the steroisomer 1a are formed with a 1:1 metal-to-ligand ratio. Ligand sites are the carboxylate and the phenolate anions and the two nitrogen atoms. Two equivalent ferri-pyochelin moieties are held together by a hydroxy and an acetate unit which satisfy the remaining two coordination sites of Fe3+.

Mass spectrometry and isotopes: a century of research and discussion.

In 1815, the British physician William Prout had advanced the theory that the molecular masses of elements were multiples of the mass of hydrogen. This "whole number rule" (and especially deviations from it) played an important role in the discussion whether elements could be mixtures of isotopes. F.

Isolation of an N-alkylated benzylamine derivative from Pseudomonas putida BTP1 as elicitor of induced systemic resistance in bean.

Root treatment of Phaseolus vulgaris with the nonpathogenic Pseudomonas putida BTP1 led to significant reduction of the disease caused by the pathogen Botrytis cinerea on leaves. The molecular determinant of P. putida BTP1 mainly responsible for the induced systemic resistance (ISR) was isolated from cell-free culture fluid after growth of the strain in the iron-poor casamino acid medium.

The pyoverdins of Pseudomonas syringae and Pseudomonas cichorii.

The structure elucidation of the cyclic (lactonic) forms of the pyoverdins with a succinamide side chain originally produced by the closely related species Pseudomonas syringae and P. cichorii is reported. Mass spectrometry and nuclear magnetic resonance analyses as well as the determination of the configuration of the amino acids after degradation indicate that these two pyoverdins differ only by the replacement of the first in-chain serine by glycine.

Half protons or doubly charged protons? The history of metastable ions.

The history of metastable ions is intertwined with that of ions formed by collision-induced dissociation (CID), and frequently the genesis of the two ion types cannot be strictly separated. Originally, metastable ions were considered a curiosity or even a nuisance, being responsible for "humps" in the base line of the recorded mass spectra. In their heyday metastable ions were recognized as having importance for establishing fragmentation sequences and for distinguishing between isomeric ion structures.

The stereoisomers of pyochelin, a siderophore of Pseudomonas aeruginosa.

The Pseudomonas aeruginosa siderophore pyochelin is obtained from the bacterial culture medium as a mixture of two epimers. Chromatically isolated pure stereoisomers equilibrate readily in most solvents. Experiments will be reported which allow to isolate one of the isomers in pure form and which shed some additional light on the epimerization reaction.

The Pseudomonas siderophore quinolobactin is synthesized from xanthurenic acid, an intermediate of the kynurenine pathway.

To cope with iron deficiency fluorescent pseudomonads produce pyoverdines which are complex peptidic siderophores that very efficiently scavenge iron. In addition to pyoverdine some species also produce other siderophores. Recently, it was shown that Pseudomonas fluorescens ATCC 17400 produces the siderophore quinolobactin, an 8-hydroxy-4-methoxy-2-quinoline carboxylic acid (Mossialos, D.

The pyoverdin of Pseudomonas fluorescens G173, a novel structural type accompanied by unexpected natural derivatives of the corresponding ferribactin.

The siderophores produced by Pseudomonas fluorescens G173 are unusual in several respects. So far all pyoverdins with a C-terminal cyclopeptidic substructure have in common that the epsilon-amino group of an in-chain Lys is bound amidically to the carboxyl group of a C-terminal Ser or Thr and that N5-formyl-N5-hydroxy Orn (FoOHOrn) is the next amino acid after Lys. FoOHOrn may (cyclotetrapeptidic structures) be or may not (cyclotripeptidic structures) be followed by a further amino acid.

The pyoverdine from Pseudomonas chlororaphis D-TR133 showing mutual acceptance with the pyoverdine of Pseudomonas fluorescens CHAO.

From Pseudomonas chlororaphis D-TR 133 a pyoverdine was isolated and its primary structure were elucidated by spectroscopic methods and degradation reactions. Despite some structural differences, its Fe(III) complex and that of the pyoverdine from Pseudomonas fluorescens CHA0 were taken up by either strain with a high rate. This is explained by a structural similarity between the two pyoverdines which were shown to differ in their structures only by the replacement of Lys by Ala in the C-terminal part of the molecules.