1. Galectin-2 Agglutinates Helicobacter pylori via Lipopolysaccharide Containing H Type I Under Weakly Acidic Conditions.
- Author
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Sasaki T, Oyama M, Kubota M, Isshiki Y, Takeuchi T, Tanaka T, Tanikawa T, Tamura M, Arata Y, and Hatanaka T
- Subjects
- Hydrogen-Ion Concentration, Humans, Galectin 3 metabolism, Galectin 3 chemistry, Protein Binding, Agglutination, Galectins metabolism, Galectins chemistry, Helicobacter pylori metabolism, Lipopolysaccharides metabolism, Lipopolysaccharides chemistry, Galectin 2 metabolism, Galectin 2 chemistry
- Abstract
Galectins are β-galactoside-binding animal lectins involved in various biological functions, such as host defense. Galectin-2 and -3 are members of the galectin family that are expressed in the stomach, including the gastric mucosa and surface mucous cells. Galectin-3 exhibits aggregation and bactericidal activity against Helicobacter pylori in a β-galactoside-dependent manner. We previously reported that galectin-2 has the same activity under neutral pH conditions. In this study, the H. pylori aggregation activity of galectin-2 was examined under weakly acidic conditions, in which H. pylori survived. Galectin-2 agglutinated H. pylori even at pH 6.0, but not at pH 5.0, correlating with its structural stability, as determined using circular dichroism. Additionally, galectin-2 binding to the lipopolysaccharide (LPS) of H. pylori cultured under weakly acidic conditions was investigated using affinity chromatography and Western blotting. Galectin-2 could bind to H. pylori LPS containing H type I, a Lewis antigen, in a β-galactoside-dependent manner. In contrast, galectin-3 was structurally more stable than galectin-2 under acidic conditions and bound to H. pylori LPS containing H type I and Lewis X. In conclusion, galectin-2 and -3 might function cooperatively in the defense against H. pylori in the stomach under different pH conditions.
- Published
- 2024
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