Action of Clostridium perfringens neuraminidase on gangliosides GM₁ and GM₂ above and below the critical micelle concentration of substrate

Susceptibility of ganglioside GM1 to a new bacterial neuraminidase

“…Consequently, the proposed hypothesis that the monomeric form of GM1 is more susceptible to neuraminidase does not seem to be correct. The discrepancies between our results and those of [11,12] may be due to a considerably lower activity of C. perfringens neuraminidase toward GM1, which makes it difficult to estimate exactly minute differences in GM~ hydrolysis without detergent, or they may be due to the less sensitive assay procedure employed in previous experiments.…”

“…GMI below the CMC became susceptible to the C. perfringens enzyme even in the absence of bile salts [ 12]. In our experiments, neither the susceptibility of GM1 to the action ofA.…”

Human platelets express gangliosides with LKEactivity and ABH blood group activity

“…Overall, five gangliosides with A activity were identified in group A, but not group O, platelets. Evidence that sA Bands 1 through 5 were sialic acid‐containing GSLs included resistance to base hydrolysis, 1 sensitivity to endoglycocera‐midase, and sensitivity to neuraminidase 55,57 . Furthermore, the sensitivity of sA Bands 1 through 5 to neuraminidase was inhibited by NeuAc2en, a specific inhibitor of neuraminidase 56 .…”

“…GSLs were resuspended by sonication in 100 μL of sodium acetate buffer (10m M , pH 7.1) containing 0.75 mg per mL of sodium cholate. Clostridium perfringens neuraminidase (Type V, EC 3.2.1.18; Sigma: 10 mU/mL final) was added, and the mixture was incubated for 20 hours at 37°C 54,55 . A buffer‐only control was always performed in parallel.…”

The Specificity of Viral Sialidases

“…In some cases a slow release from I13NeuSAcGgOse4Cer was found in the presence of bile salt [25], but this is not the case for the viral sialidases, with no cleavage even after 24 h in the presence of sodium cholate. Studies with Arthrohacter mreufbciens sialidase [26] provided evidence for a sialidase which can react with this substrate, and more recently Sendai virus was found to be even more efficient than the bacterial enzyme with I13Neu5AcGgOse4Cer and its oligosaccharide in the absence of detergent [9].…”