Neisseria meningitidis Serogroup B Polysialyltransferase: Insights into Substrate Binding

Abstract

On the loose: We report an STD NMR spectroscopic study of the polysialyltransferase from Neisseria meningitidis serogroup B (NmB‐polyST). The spectra reveal that the cytosine and ribose moiety receive more saturation than the sialic acid residue of CMP‐Neu5Ac. This loose binding enables a fast and efficient sialyl transfer to the acceptor substrate. Our analysis offers a view of the structural determinants necessary for binding to NmB‐polyST that provide the basis for the development of novel NmB‐polyST inhibitors.

Biochemical and Biophysical Characterization of the Sialyl-/Hexosyltransferase Synthesizing the Meningococcal Serogroup W135 Heteropolysaccharide Capsule

“…In contrast, if DP3 was complexed with the recombinant NmB capsule polymerase (a sialyltransferase produces a homopolymer of ␣(2,8)-linked sialic acids), the saturation was found to be lowest for the nonreducing end sugar (47). Understanding the molecular reasons for these differences needs additional work, but it should be mentioned at this point that DP3 in the case of SiaD W-135 is the acceptor of the galactosyltransferase domain, which may have different stereochemical requirements compared with sialyltransferases.…”

“…In both domains the nucleotide moieties (CMP and UDP) receive highest saturation, whereas the sugar moieties bind weaker. This binding mode has been previously described and was suggested to facilitate the transfer process (29,46,47). A particular feature in CMP-Neu5Ac binding is the tight contact that the N-acetamido group of sialic acid makes to the protein.…”

Direct Investigation of the Aspergillus GDP‐Mannose Transporter by STD NMR Spectroscopy

“…The importance of the H1 proton of the ribose moiety for the interaction of nucleotide sugars with their corresponding binding protein has been previously reported and our finding is in good agreement with the literature. [17][18][19][20] To address the question of whether the observed interaction of GDP-Man with Asp-GeF is due to binding of the endogenous GMT, a number of control NMR experiments were performed. Figure 2 C shows a clear decrease in STD signals upon denaturing of protein associated with Asp-GeF (Asp-GeF-DN) by heating the Golgi preparation to 70 8C for 15 min prior to the addition of GDP-Man.…”

The Capsule Polymerase CslB of Neisseria meningitidis Serogroup L Catalyzes the Synthesis of a Complex Trimeric Repeating Unit Comprising Glycosidic and Phosphodiester Linkages

“…In this context, we focused our work on capsule polymerases (CPs) of both pathogenic and rarely occurring meningococcal serogroups and thereby follow two research lines: (i) exploitation of recombinant CPs for in vitro production of glycoconjugate vaccines (30,31) and (ii) delineation of structure-function relationships as a basis for drug target evaluation (32)(33)(34)(35)(36)(37)(38)(39). Recently, we cloned and functionally expressed the CPs from serogroups A (CsaB) and X (CsxA) (30,31).…”