Mapping Molecular Recognition of β1,3-1,4-Glucans by a Surface Glycan-Binding Protein from the Human Gut Symbiont Bacteroides ovatus

With the knowledge of bacterial gene systems encoding proteins that target dietary carbohydrates as a source of nutrients and their importance for human health, major efforts are being made to understand carbohydrate recognition by various commensal bacteria. Here, we describe an integrative strategy that combines carbohydrate microarray technology with structural studies to further elucidate the molecular determinants of carbohydrate recognition by BoSGBP MLG -A, a key protein expressed at the surface of Bacteroides ovatus for utilization of mixed-linkage β1,3-1,4-glucans.

Humoral Immune Responses to Amebic Liver Abscess

Background: Amebic liver abscess (ALA) is an ancient parasitic disease caused by E. histolytica described first by Hippocrates. It is endemic worldwide, mainly in tropic and subtropics countries. About 50 million true E. histolytica infections and approximately 100,000 deaths occur each year globally. In Bangladesh, exact incidences of amebic liver abscess cases are not estimated, but hospital reports indicate that it is endemic. Immunity and immune responses in acute and post infections of ALA are not well understood to date. However, the understanding of immunology is essential to know disease progression, recovery, morbidity, and mortality as well as diagnosis and newer prevention strategies like vaccine development. In this 15-month prospective and follow-up study, different antibody responses are estimated periodically. Methods: About 90 amebic liver abscess patients diagnosed initially by ultra-sonogram confirmed followed by Real-Time PCR were selected for this study. All were admitted into Rajshahi Medical College Hospital, Bangladesh. Antibody responses against different antigens, which include Serum anti-lectin IgG, Salivary anti-CRD (carbohydrate recognition domain) Ig A, and Stool anti-CRD (carbohydrate recognition domain) IgA were estimated by ELISA periodically thrice, in acute stage after 06 and 09 months and between 12 and 15 months. Results: Serum anti-lectin IgG in ALA persists remarkably high well up to 09 months in 98% cases, Secretory anti-CRD IgA was also determined from the saliva, and only 36(40%) show positive titer during first 06 months, and about 40% of ALA cases show high titer of anti-CRD IgA from stool samples in first six months of infection. Conclusion: Only serum anti lectin Ig G showed significant high titer in 98% of cases in the acute stage and up to nine months of infection. TAJ 2021; 34: No-1: 05-08

The Antiviral Role of Galectins toward Influenza A Virus Infection—An Alternative Strategy for Influenza Therapy

Animal lectins are proteins with carbohydrate recognition activity. Galectins, the β-galactoside binding lectins, are expressed in various cells and have been reported to regulate several immunological and physiological responses. Recently, some galectins have been reported to regulate some viral infections, including influenza A virus (IAV); however, the mechanism is still not fully understood. Thus, we aim to review systemically the roles of galectins in their antiviral functions against IAVs. The PRISMA guidelines were used to select the eligible articles. Results indicated that only Galectin-1, Galectin-3, and Galectin-9 were reported to play a regulatory role in IAV infection. These regulatory effects occur extracellularly, through their carbohydrate recognition domain (CRD) interacting with glycans expressed on the virus surface, as well as endogenously, in a cell–cell interaction manner. The inhibition effects induced by galectins on IAV infection were through blocking virus–host receptors interaction, activation of NLRP-3 inflammasome, augment expression of antiviral genes and related cytokines, as well as stimulation of Tim-3 related signaling to enhance virus-specific T cells and humoral immune response. Combined, this study concludes that currently, only three galectins have reported antiviral capabilities against IAV infection, thereby having the potential to be applied as an alternative anti-influenza therapeutic strategy.

Binding modes of methyl α-d-glucopyranoside to an artificial receptor in crystalline complexes

Complexes formed between methyl α-d-glucopyranoside and an artificial receptor represent a valuable source of information about the basic molecular features of carbohydrate recognition.

Cholesteryl glucosides signal through the carbohydrate recognition domain of the macrophage inducible C-type lectin (mincle)

H. pylori derived cholesteryl glycosides signal through the Carbohydrate Recognition Domain (CRD) of the Macrophage inducible C-type lectin (Mincle).

Synthesis of regioisomeric maltose-based Man/Glc glycoclusters to control glycoligand presentation in 3D space

The investigation of carbohydrate recognition in a natural environment suffers from the complexity of overlapping functional effects such as multivalency and heteromultivalency effects. Another key factor in carbohydrate recognition is...

Selenium Chalcogen bonds are involved in protein-carbohydrate recognition: A combined PDB and theoretical study.

In this manuscript the ability of Selenium carbohydrates to undergo Chalcogen bonding (ChB) interactions with protein residues has been studied at the RI-MP2/def2-TZVP level of theory. An inspection of the...