Structural characterization of lipid A from nontypeable and type f Haemophilus influenzae: Variability of fatty acid substitution

Mikhail, I Kodess; Yildirim, Håkan H.; Lindahl, Emma; Schweda, Elke K. H.

doi:10.1016/j.ab.2005.02.020

Cited by 32 publications

(39 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The C2/C2′ and C3/C3′ positions are substituted by amide-linked and ester-linked 14∶0(3-OH), respectively. Fatty acid chains on C3′ and C2′ are further esterified by 14∶0 [60]. The isolates analyzed in this work showed a major lipid A species corresponding to the same hexa-acylated form ( m/z 1,824) described by Mikhail and co-workers.…”

Section: Resultssupporting

confidence: 71%

“…The isolates analyzed in this work showed a major lipid A species corresponding to the same hexa-acylated form ( m/z 1,824) described by Mikhail and co-workers. Other ion peaks detected ( m/z 1,744, and m/z 1,388) had also been previously found [60]. These peaks may represent the monophosphorylated hexa-acylated lipid A, and a tetra-acyl lipid A containing two 2-amino-2-deoxyglucose residues, two phosphates, three 14∶0(3-OH), and one 14∶0(3-OH), respectively (Figure S1A and Table S3 in File S1).…”

Section: Resultssupporting

confidence: 68%

See 1 more Smart Citation

Characterization of Nontypable Haemophilus influenzae Isolates Recovered from Adult Patients with Underlying Chronic Lung Disease Reveals Genotypic and Phenotypic Traits Associated with Persistent Infection

et al. 2014

View full text Add to dashboard Cite

Nontypable Haemophilus influenzae (NTHi) has emerged as an important opportunistic pathogen causing infection in adults suffering obstructive lung diseases. Existing evidence associates chronic infection by NTHi to the progression of the chronic respiratory disease, but specific features of NTHi associated with persistence have not been comprehensively addressed. To provide clues about adaptive strategies adopted by NTHi during persistent infection, we compared sequential persistent isolates with newly acquired isolates in sputa from six patients with chronic obstructive lung disease. Pulse field gel electrophoresis (PFGE) identified three patients with consecutive persistent strains and three with new strains. Phenotypic characterisation included infection of respiratory epithelial cells, bacterial self-aggregation, biofilm formation and resistance to antimicrobial peptides (AMP). Persistent isolates differed from new strains in showing low epithelial adhesion and inability to form biofilms when grown under continuous-flow culture conditions in microfermenters. Self-aggregation clustered the strains by patient, not by persistence. Increasing resistance to AMPs was observed for each series of persistent isolates; this was not associated with lipooligosaccharide decoration with phosphorylcholine or with lipid A acylation. Variation was further analyzed for the series of three persistent isolates recovered from patient 1. These isolates displayed comparable growth rate, natural transformation frequency and murine pulmonary infection. Genome sequencing of these three isolates revealed sequential acquisition of single-nucleotide variants in the AMP permease sapC, the heme acquisition systems hgpB, hgpC, hup and hxuC, the 3-deoxy-D-manno-octulosonic acid kinase kdkA, the long-chain fatty acid transporter ompP1, and the phosphoribosylamine glycine ligase purD. Collectively, we frame a range of pathogenic traits and a repertoire of genetic variants in the context of persistent infection by NTHi.

show abstract

Section: Resultssupporting

confidence: 71%

Section: Resultssupporting

confidence: 68%

Characterization of Nontypable Haemophilus influenzae Isolates Recovered from Adult Patients with Underlying Chronic Lung Disease Reveals Genotypic and Phenotypic Traits Associated with Persistent Infection

et al. 2014

View full text Add to dashboard Cite

show abstract

“…However, the general structure of lipid A is very different from the majority of lipid classes, e.g., glycerolipids, glycerophospholipids, and sphingolipids, which were well characterized by AMDMS-SL builtin database. In addition, the initial analysis of structures by tandem mass spectrometry alone is often not sufficient to decipher the structures of lipid A, which we have found often require exhaustive MS n analysis to successfully characterize the isobaric components [7,10,11,22,23].…”

Section: Introductionmentioning

confidence: 99%

Automated Lipid A Structure Assignment from Hierarchical Tandem Mass Spectrometry Data

Ting

Shaffer

Jones

et al. 2011

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

Infusion-based electrospray ionization (ESI) coupled to multiple-stage tandem mass spectrometry (MS n ) is a standard methodology for investigating lipid A structural diversity (Shaffer et al. J. Am. Soc. Mass. Spectrom. 18(6), [1080][1081][1082][1083][1084][1085][1086][1087][1088][1089][1090][1091][1092] 2007). Annotation of these MS n spectra, however, has remained a manual, expert-driven process. In order to keep up with the data acquisition rates of modern instruments, we devised a computational method to annotate lipid A MS n spectra rapidly and automatically, which we refer to as hierarchical tandem mass spectrometry (HiTMS) algorithm. As a first-pass tool, HiTMS aids expert interpretation of lipid A MS n data by providing the analyst with a set of candidate structures that may then be confirmed or rejected. HiTMS deciphers the signature ions (e.g., A-, Y-, and Z-type ions) and neutral losses of MS n spectra using a species-specific library based on general prior structural knowledge of the given lipid A species under investigation. Candidates are selected by calculating the correlation between theoretical and acquired MS n spectra. At a false discovery rate of less than 0.01, HiTMS correctly assigned 85% of the structures in a library of 133 manually annotated Francisella tularensis subspecies novicida lipid A structures. Additionally, HiTMS correctly assigned 85% of the structures in a smaller library of lipid A species from Yersinia pestis demonstrating that it may be used across species.

show abstract

“…Along the lines of recent studies by our group (9, 10) and others (11)(12)(13)(14)(15)(16)(17) on the detailed analysis of lipid A acylation patterns, we have employed multistage mass spectrometry (MS n ) 2 to fully investigate the V. fischeri lipid A. Using MS n methods in conjunction with selective chemical treatments, a structural model for the V. fischeri lipid A has emerged emphasizing microheterogeneity and a novel modification not previously associated with lipid A structures.…”

mentioning

confidence: 99%

The Lipid A from Vibrio fischeri Lipopolysaccharide

Phillips

Adin

Stabb

et al. 2011

Journal of Biological Chemistry

View full text Add to dashboard Cite

Vibrio fischeri, a bioluminescent marine bacterium, exists in an exclusive symbiotic relationship with the Hawaiian bobtail squid, Euprymna scolopes, whose light organ it colonizes. Previously, it has been shown that the lipopolysaccharide (LPS) or free lipid A of V. fischeri can trigger morphological changes in the juvenile squid's light organ that occur upon colonization. To investigate the structural features that might be responsible for this phenomenon, the lipid A from V. fischeri ES114 LPS was isolated and characterized by multistage mass spectrometry (MS n ). A microheterogeneous mixture of mono-and diphosphorylated diglucosamine disaccharides was observed with variable states of acylation ranging from tetra-to octaacylated forms. All lipid A species, however, contained a set of conserved primary acyl chains consisting of an N- The bioluminescent bacterium Vibrio fischeri exists in a symbiotic relationship with the Hawaiian bobtail squid, Euprymna scolopes. Colonization of the juvenile squid's light organ by V. fischeri begins within hours of hatching (1). From the complex bacterial community present in seawater, V. fischeri, which represents less than 1% of the bacterial population, is exclusively recruited by E. scolopes in a multistep winnowing process (2). As the colonization of the juvenile's light organ progresses, a series of developmental changes occur in the tissues. The most dramatic of these morphogenetic events is the loss of a superficial ciliated field of cells important for the initial recruitment of V. fischeri. This process occurs over the ϳ96 -120 h following initial colonization by the symbiont (2) and does not occur without interactions with the symbiont in the deep crypt regions of the organ. Once the colonization is established, the squid continues to maintain a population of V. fischeri in its light organ, with cycles of daily flushing and repopulation by residual bacteria.The selection process that leads to the exclusive symbiotic relationship between V. fischeri and E. scolopes involves the interaction of bacterial surface components with host tissues. Previously, we showed that bacterial lipopolysaccharide (LPS) and lipid A can induce early stage apoptosis in the cells of the ciliated field of the juvenile squid's light organ (3). However, the effect was not species-specific, suggesting that a conserved portion of the lipid A may be the responsible component of the LPS structure (3). In later stages of the colonization process, bacterial peptidoglycan acts synergistically with LPS to induce most, if not all, of light organ morphogenesis (4).How the developmental signals of bacterial LPS and peptidoglycan, which are presented by the symbionts in the deep crypts of the light organ, are conveyed to the superficial tissue remains unknown, but one piece of the puzzle has recently been discovered. At hatching, the light organ has high levels of nitric oxide (NO). Following symbiont colonization of the crypts, the levels of both NO and the enzyme that catalyzes its production, nitric-o...

show abstract

Structural characterization of lipid A from nontypeable and type f Haemophilus influenzae: Variability of fatty acid substitution

Cited by 32 publications

References 41 publications

Characterization of Nontypable Haemophilus influenzae Isolates Recovered from Adult Patients with Underlying Chronic Lung Disease Reveals Genotypic and Phenotypic Traits Associated with Persistent Infection

Characterization of Nontypable Haemophilus influenzae Isolates Recovered from Adult Patients with Underlying Chronic Lung Disease Reveals Genotypic and Phenotypic Traits Associated with Persistent Infection

Automated Lipid A Structure Assignment from Hierarchical Tandem Mass Spectrometry Data

The Lipid A from Vibrio fischeri Lipopolysaccharide

Contact Info

Product

Resources

About