Temperature-Dependent Variations and Intraspecies Diversity of the Structure of the Lipopolysaccharide of Yersinia pestis^,

Abstract

Yersinia pestis spread throughout the Americas in the early 20th century, and it occurs predominantly as a single clone within this part of the world. However, within Eurasia and parts of Africa there is significant diversity among Y. pestis strains, which can be classified into different biovars (bv.) and/or subspecies (ssp.), with bv. orientalis/ssp. pestis most closely related to the American clone. To determine one aspect of the relatedness of these different Y. pestis isolates, the structure of the lipopolysaccharide (LPS) of four wild-type and one LPS-mutant Eurasian/African strains of Y. pestis was determined, evaluating effects of growth at mammalian (37 degrees C) or flea (25 degrees C) temperatures on the structure and composition of the core oligosaccharide and lipid A. In the wild-type clones of ssp. pestis, a single major core glycoform was synthesized at 37 degrees C whereas multiple core oligosaccharide glycoforms were produced at 25 degrees C. Structural differences occurred primarily in the terminal monosaccharides. Only tetraacyl lipid A was made at 37 degrees C, whereas at 25 degrees C additional pentaacyl and hexaacyl lipid A structures were produced. 4-Amino-4-deoxyarabinose levels in lipid A increased with lower growth temperatures or when bacteria were cultured in the presence of polymyxin B. In Y. pestis ssp. caucasica, the LPS core lacked D-glycero-D-manno-heptose and the content of 4-amino-4-deoxyarabinose showed no dependence on growth temperature, whereas the degree of acylation of the lipid A and the structure of the oligosaccharide core were temperature dependent. A spontaneous deep-rough LPS mutant strain possessed only a disaccharide core and a slightly variant lipid A. The diversity and differences in the structure of the Y. pestis LPS suggest important contributions of these variations to the pathogenesis of this organism, potentially related to innate and acquired immune recognition of Y. pestis and epidemiologic means to detect, classify, control and respond to Y. pestis infections.

Dioxygenases in Burkholderia ambifaria and Yersinia pestis that hydroxylate the outer Kdo unit of lipopolysaccharide

“…In many strains of Yersinia and Burkholderia, Ko replaces the distal Kdo unit of the Kdo disaccharide in LPS (10)(11)(12)(13)(14). We hypothesized that Ko might be derived from Kdo by an enzymatic hydroxylation reaction (Fig.…”

“…Two Kdo residues are usually present, one of which is linked directly to lipid A. A subset of Gramnegative bacteria, including B. cepacia (10-12), Y. pestis (13,14), and some strains of Acinetobacter (26,27), contain an unusual analog of Kdo, known as Ko, in which the axial hydrogen atom at position 3 of Kdo is replaced with an OH group (Fig. 1A).…”

“…Yersinia pestis causes "Bubonic Plague" in humans (9). These important Gram-negative pathogens synthesize an unusual isosteric analog of Kdo, known as D-glycero-D-talo-oct-2-ulosonic acid (Ko) (10)(11)(12)(13)(14) in which the axial hydrogen atom at the 3-position of the outer Kdo unit is replaced with an OH group (10) (Fig. 1A).…”

LcrV Delivered via Type III Secretion System of Live Attenuated Yersinia pseudotuberculosis Enhances Immunogenicity against Pneumonic Plague

“…This could have been due to the method of preparation of YpL, since YpL was made from a lysate of Y. pestis KIMϩ(pCD1Ap) cultured overnight in the calcium-chelated HIB medium at 37°C (76). As we know, tetra-acylated lipid A of Y. pestis KIM6ϩ(pCD1Ap) predominated at 37°C (68,78,(101)(102)(103). Thus, predominant tetraacylated lipid A in Y. pestis whole-cell lysate prepared under this condition inhibited the induction of proinflammatory cytokines and type I interferons (80), which might result in lower levels of IFN-␥, TNF-␣, and IL-17 production.…”

Automated Lipid A Structure Assignment from Hierarchical Tandem Mass Spectrometry Data

“…Yp lipid A has also been observed to be heavily modified with up to two aminoarabinose (Ara4N) moieties [10]. At the mammalian host temperature of 37°C, the major Yp lipid A structures consists of a β-1,6-linked diglucosamine backbone with two phosphate groups and four primary 14:0 fatty acids [36][37][38]. Such tetra-acylated lipid A with four identical fatty acids distributed evenly on the reducing and non-reducing end is likely to result in symmetric lipid A structures.…”