Origin and evolution of nonulosonic acid synthases and their relationship with bacterial pathogenicity revealed by a large-scale phylogenetic analysis

Abstract

Nonulosonic acids (NulOs) are a group of nine-carbon monosaccharides with different functions in nature. N-acetylneuraminic acid (Neu5Ac) is the most common NulO. It covers the membrane surface of all human cells and is a central molecule in the process of self-recognition via SIGLECS receptors. Some pathogenic bacteria escape the immune system by copying the sialylation of the host cell membrane. Neu5Ac production in these bacteria is catalysed by the enzyme NeuB. Some bacteria can also produce other NulOs named pseudaminic and legionaminic acids, through the NeuB homologues PseI and LegI, respectively. In Opisthokonta eukaryotes, the biosynthesis of Neu5Ac is catalysed by the enzyme NanS. In this study, we used publicly available data of sequences of NulOs synthases to investigate its distribution within the three domains of life and its relationship with pathogenic bacteria. We mined the KEGG database and found 425 NeuB sequences. Most NeuB sequences (58.74 %) from the KEGG orthology database were classified as from environmental bacteria; however, sequences from pathogenic bacteria showed higher conservation and prevalence of a specific domain named SAF. Using the HMM profile we identified 13 941 NulO synthase sequences in UniProt. Phylogenetic analysis of these sequences showed that the synthases were divided into three main groups that can be related to the lifestyle of these bacteria: (I) predominantly environmental, (II) intermediate and (III) predominantly pathogenic. NeuB was widely distributed in the groups. However, LegI and PseI were more concentrated in groups II and III, respectively. We also found that PseI appeared later in the evolutionary process, derived from NeuB. We use this same methodology to retrieve sialic acid synthase sequences from Archaea and Eukarya. A large-scale phylogenetic analysis showed that while the Archaea sequences are spread across the tree, the eukaryotic NanS sequences were grouped in a specific branch in group II. None of the bacterial NanS sequences grouped with the eukaryotic branch. The analysis of conserved residues showed that the synthases of Archaea and Eukarya present a mutation in one of the three catalytic residues, an E134D change, related to a Neisseria meningitidis reference sequence. We also found that the conservation profile is higher between NeuB of pathogenic bacteria and NanS of eukaryotes than between NeuB of environmental bacteria and NanS of eukaryotes. Our large-scale analysis brings new perspectives on the evolution of NulOs synthases, suggesting their presence in the last common universal ancestor.

Stereoisomer‐specific reprogramming of a bacterial flagellin sialyltransferase

“…The synthesis of CMP-Pse or CMP-Leg proceeds enzymatically by a series of steps (Schoenhofen et al, 2006(Schoenhofen et al, , 2009Friedrich et al, 2017), starting from activated N-acetyl-glucosamine (GlcNAc) and ultimately ending with the condensation of a 3-carbon pyruvate (such as phosphoenolpyruvate, PEP) to a pyranose derivative by Pse or Leg synthase paralogs, PseI or LegI, respectively (Fig 1A; Lewis et al, 2009;Vieira et al, 2021). The NeuB paralog is responsible for the synthesis of Neu that, unlike Pse or Leg, only harbors one acetamido group (Schoenhofen et al, 2006(Schoenhofen et al, , 2009Friedrich et al, 2017;Chidwick & Fascione, 2020).…”

Whole genome characterization of thermophilic Campylobacter species isolated from dairy manure in small specialty crop farms of Northeast Ohio

“…Further, the competition for vitamin B5 between Campylobacter and the host may affect the host immune system and increase susceptibility to other pathogens ( Yoshii et al, 2019 ). Legionaminic acid is involved in the modification of bacterial flagellin which is key for the persistence of Campylobacter in poultry and host interactions ( Howard et al, 2009 ; Stephenson et al, 2014 ; Ardissone et al, 2020 ; Vieira et al, 2021 ); however, its role in the persistence of Campylobacter in cattle and dairy manure remains unknown. The utilization of fucose in nutrient-limited conditions has been reported to provide a competitive advantage to C. jejuni by enhancing cell adhesions and biofilm production ( Day et al, 2009 ; Muraoka and Zhang, 2011 ; Stahl et al, 2011 ; Dwivedi et al, 2016 ).…”

Genetic glyco-profiling and rewiring of insulated flagellin glycosylation pathways

“…The synthesis of CMP-Pse or CMP-Leg proceeds enzymatically by series of steps [20][21][22], ultimately ending with the condensation of an activated 6-carbon monosaccharide (typically N-acetylglucosamine, GlcNAc) with 3-carbon pyruvate (such as phosphoenolpyruvate, PEP) by Pse or Leg synthase paralogs, PseI or LegI, respectively (Figure 1) [23,24], whereas the sialic acid Neu is synthesized by the NeuB paralog [20][21][22]25]. A major difference between the Pse and Leg pathways is that the former uses UDP-GlcNAc as starting material whereas the latter usually builds on GDP-GlcNAc [21,22].…”