Biological functions of sialic acid as a component of bacterial endotoxin

Dudek, Barbara; Rybka, Jacek; Bugla-Płoskońska, Gabriela; Korzeniowska‐Kowal, Agnieszka; Futoma-Kołoch, Bożena; Pawlak, Aleksandra; Gamian, Andrzej

doi:10.3389/fmicb.2022.1028796

Cited by 7 publications

(4 citation statements)

References 148 publications

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“…LPS is the major component of outer membrane of Gram-negative bacteria and consists of lipid A, oligosaccharide core, and polysaccharide O-antigen. Sialic acid (or neu5Ac) residues are typically located within O-antigen of LPS, whereas sialic acid residues are located at the terminus of O-antigen in most LOS ( 26 ). Since M. haemolytica does not appear to have a sialic acid uptake system ( nanPU ), we did not add exogenous sialic acid into growth medium.…”

Section: Resultsmentioning

confidence: 99%

Enhanced phagocytosis and complement-mediated killing of Mannheimia haemolytica serotype 1 following in-frame CMP-sialic acid synthetase ( neuA ) gene deletion

Menghwar,

Tatum,

Briggs

et al. 2023

Microbiol Spectr

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Mannheimia haemolytica is the most significant bacterial pathogen associated with the bovine respiratory disease complex. Although sialic acid is a known virulence factor in other members of Pasteurellaceae, such as Histophilus somni and Pasteurella multocida , the significance of sialic acid to the virulence of M. haemolytica is currently unknown. Therefore, the role of sialic acid as a virulence determinant of M. haemolytica was investigated by constructing an in-frame neuA [CMP-N-acetylneuraminic acid (Neu5Ac/sialic) synthetase] mutant, which was shown by high-performance anion exchange chromatographic analysis (HPAEC) to be devoid of sialic acid on the lipopolysaccharide (LPS). Both the neuA mutant and wild-type parent strains exhibited similar growth rates in the growth curve assay. Real-time qPCR and ELISA evaluation showed no differences in proinflammatory cytokine expressions (IL-1β, IL-6, and IL-8) between the neuA mutant and parent strain when peripheral blood mononuclear cells were incubated with LPS. Interestingly, the neuA mutant was three to four logs more sensitive to a whole-blood bacterial killing assay than the parent strain. Similar results were also observed in plasma and serum bacterial killing assays. Flow cytometry analyses showed higher uptake of neuA mutant by phagocytes, compared to the parent strain, in the whole-blood phagocytosis assay; however, no difference in reactive oxygen species production in neutrophils or monocytes was detected for either strain. Taken together, these results indicate that sialylation of M. haemolytica LPS plays a vital role in reducing complement-mediated and phagocytic killing. IMPORTANCE The Gram-negative coccobacillus Mannheimia haemolytica is a natural inhabitant of the upper respiratory tract in ruminants and the most common bacterial agent involved in bovine respiratory disease complex development. Key virulence factors harbored by M. haemolytica are leukotoxin, lipopolysaccharide, capsule, adhesins, and neuraminidase which are involved in evading innate and adaptive immune responses. In this study, we have shown that CMP-sialic acid synthetase ( neuA ) is necessary for the incorporation of sialic acid onto the membrane, and inactivation of neuA results in increased phagocytosis and complement-mediated killing of M. haemolytica, thus demonstrating that sialylation contributes to the virulence of M. haemolytica .

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Section: Resultsmentioning

confidence: 99%

Enhanced phagocytosis and complement-mediated killing of Mannheimia haemolytica serotype 1 following in-frame CMP-sialic acid synthetase ( neuA ) gene deletion

Menghwar,

Tatum,

Briggs

et al. 2023

Microbiol Spectr

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“…Another, compound with high peak area intensity observed in this endophyte extract of is neuraminic acid (or sialic acid). Sialic acid and its derivatives are important for the survival of the microbe inside the host organism through functions such as receptor adherence and biofilm production [70]. Thus, the specific pattern of these compounds is possibly essential for the adaptation of this endophyte to its host.…”

Section: Metabolite Profiling Using Liquid Chromatography Quadrupole ...mentioning

confidence: 99%

Biological activities and metabolic profile of endophyticBacillus haynesiifromMomordica charantia

Sharma,

Agarwal,

Bhardwaj

et al. 2024

Preprint

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Endophytes share a complex intimate relationship due to which they are capable of synthesizing metabolites that are either similar or derivative of host bioactive compounds. Such endophytes especially from medicinal plants can be prospected for commercial-scale production of the therapeutic compound. Thus, the study evaluates the antioxidant and anti-inflammatory potential of Momordica charantia fruit endophyte Bacillus haynesii R2MCFF61, and determines its metabolite profile through LC-Q-TOF-MS for the bioactive compounds produced. B. haynesii R2MCFF61 showed significant antioxidant and anti-inflammatory potential with increased DPPH scavenging activity in the standard compound and inhibition of protein denaturation respectively. The metabolic profile of this endophyte showed 23 compounds, mostly consisting of metabolites from lipid, phenylpropanoid and triterpenoid pathways. B. haynesii R2MCFF61 showed production of cucurbitane-triterpenoids namely Momordicoside K, 19-dimethoxycucurbita-5(10),6,22(E),24-tetraen-3β-ol and 23(E)-7β-methoxycucurbita-5,23,25-trien-3β-ol. These compounds are mainly produced by M. charantia fruit and their production by its endophyte is reported for the first time. Thus, these results indicate the promising therapeutic potential of B. haynesii R2MCFF61 which can be utilized as a low-cost sustainable source of these bioactive compounds.

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“…For most commensal bacteria, the SAs stand just for a nutrient source, but for pathogens (viral, bacterial, and parasite), they also play a role in invasion. SA, present in the components of some bacterial surface structures such as capsular polysaccharides, lipopolysaccharides and lipooligosaccharides, helps pathogens to evade the host’s immune response through a variety of mechanisms [ 64 , 65 , 66 ]. The unusual distribution of the sialidases, sharing similar mechanisms and even residues in different kingdoms but being irregularly distributed in closed species or even between different strains of the same one, support the possibility of horizontal gene transfer regarding these enzymes [ 67 ].…”

Section: Gut Bacterial Sialidasesmentioning

confidence: 99%

Gut Microbial Sialidases and Their Role in the Metabolism of Human Milk Sialylated Glycans

Muñoz-Provencio

Yebra

2023

IJMS

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Sialic acids (SAs) are α-keto-acid sugars with a nine-carbon backbone present at the non-reducing end of human milk oligosaccharides and the glycan moiety of glycoconjugates. SAs displayed on cell surfaces participate in the regulation of many physiologically important cellular and molecular processes, including signaling and adhesion. Additionally, sialyl-oligosaccharides from human milk act as prebiotics in the colon by promoting the settling and proliferation of specific bacteria with SA metabolism capabilities. Sialidases are glycosyl hydrolases that release α-2,3-, α-2,6- and α-2,8-glycosidic linkages of terminal SA residues from oligosaccharides, glycoproteins and glycolipids. The research on sialidases has been traditionally focused on pathogenic microorganisms, where these enzymes are considered virulence factors. There is now a growing interest in sialidases from commensal and probiotic bacteria and their potential transglycosylation activity for the production of functional mimics of human milk oligosaccharides to complement infant formulas. This review provides an overview of exo-alpha-sialidases of bacteria present in the human gastrointestinal tract and some insights into their biological role and biotechnological applications.

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Biological functions of sialic acid as a component of bacterial endotoxin

Cited by 7 publications

References 148 publications

Enhanced phagocytosis and complement-mediated killing of Mannheimia haemolytica serotype 1 following in-frame CMP-sialic acid synthetase ( neuA ) gene deletion

Enhanced phagocytosis and complement-mediated killing of Mannheimia haemolytica serotype 1 following in-frame CMP-sialic acid synthetase ( neuA ) gene deletion

Biological activities and metabolic profile of endophyticBacillus haynesiifromMomordica charantia

Gut Microbial Sialidases and Their Role in the Metabolism of Human Milk Sialylated Glycans

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