The human gut symbiont Ruminococcus gnavus shows specificity to blood group A antigen during mucin glycan foraging: Implication for niche colonisation in the gastrointestinal tract

The human gut symbiont Ruminococcus gnavus displays strain-specific repertoires of glycoside hydrolases (GHs) contributing to its spatial location in the gut. Sequence similarity network analysis identified strain-specific differences in blood-group endo-β-1,4-galactosidase belonging to the GH98 family. We determined the substrate and linkage specificities of GH98 from R. gnavus ATCC 29149, RgGH98, against a range of defined oligosaccharides and glycoconjugates including mucin. We showed by HPAEC-PAD and LC-FD-MS/MS that RgGH98 is specific for blood group A tetrasaccharide type II (BgA II). Isothermal titration calorimetry (ITC) and saturation transfer difference (STD) NMR confirmed RgGH98 affinity for blood group A over blood group B and H antigens. The molecular basis of RgGH98 strict specificity was further investigated using a combination of glycan microarrays, site-directed mutagenesis, and X-ray crystallography. The crystal structures of RgGH98 in complex with BgA trisaccharide (BgAtri) and of RgGH98 E411A with BgA II revealed a dedicated hydrogen network of residues, which were shown by site-directed mutagenesis to be critical to the recognition of the BgA epitope. We demonstrated experimentally that RgGH98 is part of an operon of 10 genes that is overexpresssed in vitro when R. gnavus ATCC 29149 is grown on mucin as sole carbon source as shown by RNAseq analysis and RT-qPCR confirmed RgGH98 expression on BgA II growth. Using MALDI-ToF MS, we showed that RgGH98 releases BgAtri from mucin and that pretreatment of mucin with RgGH98 confered R. gnavus E1 the ability to grow, by enabling the E1 strain to metabolise BgAtri and access the underlying mucin glycan chain. These data further support that the GH repertoire of R. gnavus strains enable them to colonise different nutritional niches in the human gut and has potential applications in diagnostic and therapeutics against infection.

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Transcriptional Profile of Carbohydrate Blood Group Genes in Erythroid Versus Neutrophil Differentiation of Human CD34+ Cells In Vitro.

Blood ◽

10.1182/blood.v106.11.4242.4242 ◽

2005 ◽

Vol 106 (11) ◽

pp. 4242-4242

Author(s):

Josefina H. Dykes ◽

Britt Thuresson ◽

Louise Edvardsson ◽

Tor Olofsson ◽

Martin L. Olsson

Keyword(s):

Gene Expression ◽

Blood Group ◽

Erythroid Differentiation ◽

Surface Expression ◽

Blood Groups ◽

Blood Group A ◽

Cd34 Cells ◽

Group A ◽

Neutrophil Differentiation

Abstract Carbohydrate blood groups and their corresponding antibodies are clinically important, known to be involved in conditions such as hemolytic transfusion reactions, hemolytic disease of the newborn and spontaneous abortion. However, little is understood about the developmental changes in expression of carbohydrate blood groups during hematopoiesis, with preceding studies mainly focusing on protein-based blood group molecules. We have previously identified the carbohydrate blood group A antigen as the earliest, specific marker for definitive erythroid commitment, in preference to other suggested candidates such as Kell or Glycophorin C [Br J Haematol2004;127:451–63]. With regard to this lineage-restriction point we mapped the gene expression of some clinically important carbohydrate blood group systems during erythroid versus neutrophil differentiation in vitro. Human bone marrow CD34+ cells from healthy donors, carrying the blood group A1 allele and functional secretor (FUT2) and Lewis (FUT3) genes, were cultured in vitro towards erythroid or neutrophil development and sorted on a flow cytometer into subpopulations according to their surface expression of blood group A antigen/CD117 and CD15/CD33. Sorted cells were cultured in clonogenic assays in methylcellulose or analyzed by TaqMan real-time reverse transcriptase PCR for gene expression of a number of carbohydrate blood group glycosyltransferases. Surface expression of the blood group A antigen coincided with commitment to erythroid differentiation and the expression of CD15 with neutrophil/monocytic differentiation. In gene expression studies the ABO, H (FUT1), I (IGnT) and Pk (A4GALT) genes were all expressed in freshly isolated and sorted CD34+ cells. The ABO and the H genes were up-regulated in erythroid differentiation and silenced in neutrophil differentiation. The ABO gene expression was markedly decreased in late stages of erythroid maturation. The I gene was expressed both during erythroid and neutrophil development with an increased expression in late erythroid differentiation. The Pk gene retained a low expression throughout neutrophil differentiation and was up-regulated several-fold during erythroid differentiation. There was no detectable expression of FUT3 and the gene suggested being responsible for biosynthesis of the Sda antigen, GALGT2, in either erythroid or neutrophil differentiation. Our data support the identification of the blood group A antigen as an early and specific marker for definitive erythroid differentiation. In mature cells of the myeloid lineage, the results of the gene expression studies are compatible with previous findings of gene and/or surface expression of the I and Pk blood groups but not of ABO and H. The marked increase in expression of the Pk gene during erythroid differentiation may well agree with the fact that the Pk antigen is the precursor structure of globoside, the most abundant neutral glycolipid in the erythrocyte membrane. The absence of hematopoietic FUT3 expression in Lewis gene positive individuals was expected whilst the relevance of undetectable GALGT2 expression in hematopoietic differentiation is uncertain. The role of the GALGT2 gene in surface expression of Sda has not been definitively proven and the molecular basis of different Sda phenotype variants is unknown. In conclusion, our data extend previous findings of carbohydrate blood group distribution, primarily obtained from mature blood cells and leukemic cell lines, to normal human hematopoiesis.

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A common molecular signature unifies the chitosanases belonging to families 46 and 80 of glycoside hydrolases

Canadian Journal of Microbiology ◽

10.1139/w00-080 ◽

2000 ◽

Vol 46 (10) ◽

pp. 952-955 ◽

Cited By ~ 3

Author(s):

Hugo Tremblay ◽

Josée Blanchard ◽

Ryszard Brzezinski

Keyword(s):

Amino Acids ◽

Sequence Similarity ◽

Glycosyl Hydrolase ◽

3D Structure ◽

Glycoside Hydrolases ◽

Site Directed Mutagenesis ◽

Molecular Signature ◽

Directed Mutagenesis ◽

Protein Motif ◽

Streptomyces Sp

The 3D structure-oriented alignment of the primary sequences of fourteen chitosanases, mainly of bacterial origin and belonging to families 46 and 80 of glycoside hydrolases, resulted in the identification of the following pattern common to all these enzymes: E-[DNQ]-x(8,17)-Y-x(7)-D-x-[RD]-[GP]-x-[TS]-x(3)-[AIVFLY]-G-x(5,11)-D. This pattern is proposed as the molecular signature of the chitosanases from families 46 and 80. It includes several amino acids essential for enzyme activity and (or) stability as shown by site-directed mutagenesis studies on the chitosanase from Streptomyces sp. N174. In particular, it includes two carboxylic residues directly involved in catalysis. We suggest that there is a continuum of sequence similarity between all the analyzed chitosanases, and that all these enzymes should probably be classified in one family.Key words: chitosanase, glycosyl hydrolase, protein motif.

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Purification, properties and partial amino acid sequence of the blood-group-A-gene-associated α-3-N-acetylgalactosaminyltransferase from human gut mucosal tissue

Biochemical Journal ◽

10.1042/bj2710093 ◽

1990 ◽

Vol 271 (1) ◽

pp. 93-98 ◽

Cited By ~ 20

Author(s):

N Navaratnam ◽

J B C Findlay ◽

J N Keen ◽

W M Watkins

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Blood Group ◽

Specific Activity ◽

Mucosal Tissue ◽

Human Gut ◽

Partial Amino Acid Sequence ◽

Blood Group A ◽

Group A ◽

Group B

An alpha-3-N-acetylgalactosaminyltransferase that transfers N-acetylgalactosamine from UDP-N-acetylgalactosamine to H-active structures to form A determinants was purified to homogeneity from human gut mucosal tissue of blood-group-A subjects. The mucosa was homogenized, then treated with Triton X-100, and the solubilized enzyme was purified by affinity chromatography on UDP-hexanolamine-agarose and octyl-Sepharose CL-4B. Enzyme activity was recovered in 44% yield with a specific activity of approx. 7 mumol/min per mg. The only effective acceptor substrates for the transferase were those containing a subterminal β-galactosyl residue substituted at the O-2 position with L-fucose. The purified enzyme had a weak capacity to transfer D-galactose from UDP-D-galactose to similar acceptors to make blood-group-B determinants. H.p.l.c. and SDS/PAGE analysis indicated an Mr of 40,000 for the purified enzyme. For the first time a partial amino acid sequence Xaa-Ser-Leu-Pro-Arg-Met-Val-Tyr-Pro-Gln-Ile-Ser?-Val-Leu was obtained for the N-terminal region of the soluble alpha-3-N-acetylgalactosaminyltransferase.

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The SARS-CoV-2 receptor-binding domain preferentially recognizes blood group A

Blood Advances ◽

10.1182/bloodadvances.2020003259 ◽

2021 ◽

Vol 5 (5) ◽

pp. 1305-1309 ◽

Cited By ~ 2

Author(s):

Shang-Chuen Wu ◽

Connie M. Arthur ◽

Jianmei Wang ◽

Hans Verkerke ◽

Cassandra D. Josephson ◽

...

Keyword(s):

Blood Group ◽

Sequence Similarity ◽

Blood Group Antigens ◽

Receptor Binding Domain ◽

Respiratory Epithelial Cells ◽

Blood Group A ◽

Key Points ◽

Group A ◽

Lectin Family ◽

Respiratory Epithelial

Key Points The RBD of SARS-CoV-2 shares sequence similarity with an ancient lectin family known to bind blood group antigens. SARS-CoV-2 RBD binds the blood group A expressed on respiratory epithelial cells, directly linking blood group A and SARS-CoV-2.

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ABO blood group antigen therapy: a potential new strategy against solid tumors

Scientific Reports ◽

10.1038/s41598-021-95794-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Qiong Luo ◽

Mingxin Pan ◽

Hao Feng ◽

Lei Wang

Keyword(s):

Blood Group ◽

Killer Cell ◽

Membrane Attack Complex ◽

Blood Group Antigen ◽

Control Group ◽

Abo Blood Group ◽

Blood Group System ◽

Blood Group A ◽

Group A

AbstractThe economic burden of tumors is increasing, so there is an urgent need to develop new therapies for their treatment. Killing tumors by activating complement is an effective strategy for the treatment. We used the ABO blood group system and the corresponding antibodies to activate the killer cell capacity of the complement system. After the construction of a mouse model containing blood group A antibodies and inoculating colorectal cancer and breast cancer cells into the axillae of the mice, intratumoural injection using a lentivirus carrying a blood group antigen as a drug significantly reduced the tumor volume of the mice. Compared with the control group, the content of the C5b-9 complement membrane attack complex in the tumors of mice treated with the blood group A antigen was significantly increased, and the proportion of NK cells was also significantly increased. In vitro cell-based experiments proved that tumor cells expressing blood group A antigens showed significantly inhibited cell proliferation when added to serum containing blood group A antibodies. These results all prove that the ABO blood group antigen may become a powerful tool for the treatment of tumors in patients.

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Plasmodium falciparum erythrocyte rosetting is mediated by promiscuous lectin-like interactions.

Journal of Experimental Medicine ◽

10.1084/jem.176.5.1311 ◽

1992 ◽

Vol 176 (5) ◽

pp. 1311-1317 ◽

Cited By ~ 122

Author(s):

J Carlson ◽

M Wahlgren

Keyword(s):

Plasmodium Falciparum ◽

Blood Group ◽

Animal Species ◽

Blood Group Antigens ◽

Blood Group A ◽

Group A ◽

Group B ◽

Different Strains ◽

B Blood Group

Herein we describe an assay that was developed to quantitate the binding of normal red blood cells (RBC), labeled with carboxy fluorescein diacetate (C-FDA), to rosetting Plasmodium falciparum-infected RBC. The binding of RBC obtained from various animal species or humans to different strains or clones of rosetting P. falciparum-infected RBC was studied. A strain-specific preference of rosetting was observed for either blood group A/AB or B/AB RBC for all parasites tested. The higher affinity of rosette binding of blood group A, B, or AB vs. O RBC was reflected in larger rosettes when a given parasite was grown in RBC of the preferred blood group. The small size of the rosettes formed when P. falciparum was grown in blood group O RBC may be the in vitro correlate of the relative protection against cerebral malaria afforded by belonging to blood group O rather than to blood group A or B. Rosettes of a blood group A-preferring parasite could be completely disrupted by heparin only when grown in blood group O or B RBC, but not when grown in blood group A RBC. Similarly, the rosettes of a blood group B-preferring parasite could be more easily disrupted by heparin when grown in blood group O or A RBC than when grown in blood group B RBC. Several different saccharides inhibited rosetting of group O RBC, including two monosaccharides that are basic components of heparin. The rosetting of the same parasites grown in blood group A or B RBC was less sensitive to heparin and was specifically inhibited only by the terminal mono- and trisaccharides of the A and the B blood group antigens, the H disaccharide, and fucose. Our results suggest that rosetting is mediated by multiple lectin-like interactions, the usage of which rely on the parasite phenotype and whether the receptors are present on the host cell or not.

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