scholarly journals Glycan detecting tools developed from the Clostridium botulinum whole hemagglutinin complex

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ea Kristine Clarisse Tulin ◽  
Chiaki Nakazawa ◽  
Tomomi Nakamura ◽  
Shion Saito ◽  
Naoki Ohzono ◽  
...  
Keyword(s):  
Cell Surface ◽  
Clostridium Botulinum ◽  
Staining Pattern ◽  
Enzyme Treatment ◽  
Glycan Microarray ◽  
Acetylneuraminic Acid ◽  
Toxin Complex ◽  
Type C ◽  
High Binding Affinity

AbstractLectins are proteins with the ability to recognize and bind to specific glycan structures. These molecules play important roles in many biological systems and are actively being studied because of their ability to detect glycan biomarkers for many diseases. Hemagglutinin (HA) proteins from Clostridium botulinum type C neurotoxin complex; HA1, HA2, and HA3 are lectins that aid in the internalization of the toxin complex by binding to glycoproteins on the cell surface. HA1 mutants have been previously reported, namely HA1 W176A/D271F and HA1 N278A/Q279A which are specific to galactose (Gal)/N-acetylgalactosamine (GalNAc) and N-acetylneuraminic acid (Neu5Ac) sugars, respectively. In this study, we utilized HA1 mutants and expressed them in complex with HA2 WT and HA3 WT to produce glycan detecting tools with high binding affinity. Particularly, two types were made: Gg and Rn. Gg is an Alexa 488 conjugated lectin complex specific to Gal and GalNAc, while Rn is an Alexa 594 conjugated lectin complex specific to Neu5Ac. The specificities of these lectins were identified using a glycan microarray followed by competitive sugar inhibition experiments on cells. In addition, we confirmed that Gg and Rn staining is clearly different depending on cell type, and the staining pattern of these lectins reflects the glycans present on the cell surface as shown in enzyme treatment experiments. The availability of Gg and Rn provide us with new promising tools to study Gal, GalNAc, and Neu5Ac terminal epitopes which can aid in understanding the functional role of glycans in physiological and pathological events.

Biosynthesis of N-Acetylneuraminic Acid in Cells Lacking UDP-N-Acetylglucosamine 2-Epimerase/ N-Acetylmannosamine Kinase

2001 ◽  
Vol 382 (2) ◽  
pp. 291-297 ◽  
Author(s):  
Stephan Hinderlich ◽  
Markus Berger ◽  
Oliver T. Keppler ◽  
Michael Pawlita ◽  
Werner Reutter
Keyword(s):  
Cell Surface ◽  
Cell Line ◽  
Kinase Activity ◽  
Gel Filtration ◽  
Acetylneuraminic Acid ◽  
Biological Recognition ◽  
Functionally Impaired ◽  
Cell Surface Glycoconjugates

Abstract The first two steps in mammalian biosynthesis of Nacetylneuraminic acid, an important carbohydrate moiety in biological recognition systems, are performed by the bifunctional enzyme UDPNacetylglucosamine 2-epimerase/Nacetylmannosamine kinase. A subclone of the human B lymphoma cell line BJAB K20, lacking UDPNacetylglucosamine 2- epimerase/Nacetylmannosamine kinase mRNA as well as epimerase activity, displayed hyposialylated, functionally impaired cell surface glycoconjugates. Here we show that this cell line surprisingly still retains Nacetylmannosamine kinase activity. A gel filtration analysis of BJAB K88 control cells, which express UDPNacetylglucosamine 2-epimerase/Nacetylmannosamine kinase, revealed two Nacetylmannosamine kinase activity peaks, one coeluting with UDPNacetylglucosamine 2-epimerase activity and one coeluting with Nacetylglucosamine kinase. For this enzyme previous studies already showed ManNAc kinase activity in vitro. In contrast, the hyposialylated BJAB K20 subclone displayed only the Nacetylmannosamine kinase peak, comigrating with Nacetylglucosamine kinase. The CMPNacetylneuraminic acid content of both K88 and K20 cells and the sialylation of cell surface glycoconjugates of K20 cells could be significantly increased by supple menting the medium with Nacetylmannosamine. This Nacetylmannosamineinduced increase was drastically reduced by cosupplementation with Nacetylglucosamine only in K20 cells. We therefore propose the phosphorylation of Nacetylmannosamine as a hitherto unrecognized role of Nacetylglucosamine kinase in living cells.

Bacteriophages of Clostridium botulinum

1972 ◽  
Vol 18 (1) ◽  
pp. 67-76 ◽  
Author(s):  
C. E. Dolman ◽  
Eva Chang
Keyword(s):  
Clostridium Botulinum ◽  
Phage Type ◽  
Phage Group ◽  
Flexible Tail ◽  
Group 4 ◽  
Group 3 ◽  
Type C ◽  
Group 2 ◽  
Group 1

Temperate bacteriophages of diverse morphology were demonstrated by electron microscopy in toxigenic cultures of Clostridium botulinum. The 41 strains examined included 23 type E and multiple representatives of all other types. Cultures induced with mitomycin-C generally gave better yields, but phages were also demonstrable in untreated cultures.A provisional grouping of toxigenic types into four categories is suggested, based mainly upon associated phage patterns. Group 1 comprises types A, B, and F (all proteolytic), many of whose cultures showed an icosahedral contractile phage; others contained a "bullrushy" phage with elongated head and long flexible tail; some strains yielded both. Group 2, types B and F (non-proteolytic), were associated with icosahedral contractile phages; the latter also had an octahedral flexible phage. Group 3, types C and D, yielded conspicuously large phages with octahedral heads and very long sheathed tails. One type C strain produced a long-tailed icosahedral phage. Type E phages constituted group 4. These were icosahedral with tails generally contracted but sometimes flexible, often accompanied by superfluous sheathed tail-like structures resembling certain bacteriocins. Although non-toxigenic "OS" mutants of types A, B, E, and F were phageless, two non-toxic type E strains yielded phages. The possible role of lysogeny in the toxigenicity of certain types of this species is likely to prove difficult to elucidate.

scholarly journals O-acetylated N-acetylneuraminic acid as a novel target for therapy in human pre-B acute lymphoblastic leukemia

2013 ◽  
Vol 210 (4) ◽  
pp. 805-819 ◽  
Author(s):  
Reshmi Parameswaran ◽  
Min Lim ◽  
Anna Arutyunyan ◽  
Hisham Abdel-Azim ◽  
Christian Hurtz ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Acute Lymphoblastic Leukemia ◽  
Cell Surface ◽  
Lymphoblastic Leukemia ◽  
Minimal Cell ◽  
Acetylneuraminic Acid ◽  
Development Of Resistance ◽  
Novel Target

The development of resistance to chemotherapy is a major cause of relapse in acute lymphoblastic leukemia (ALL). Though several mechanisms associated with drug resistance have been studied in detail, the role of carbohydrate modification remains unexplored. Here, we investigated the contribution of 9-O-acetylated N-acetylneuraminic acid (Neu5Ac) to survival and drug resistance development in ALL cells. A strong induction of 9-O-acetylated Neu5Ac including 9-O-acetyl GD3 was detected in ALL cells that developed resistance against vincristine or nilotinib, drugs with distinct cytotoxic mechanisms. Removal of 9-O-acetyl residues from Neu5Ac on the cell surface by an O-acetylesterase made ALL cells more vulnerable to such drugs. Moreover, removal of intracellular and cell surface–resident 9-O-acetyl Neu5Ac by lentiviral transduction of the esterase was lethal to ALL cells in vitro even in the presence of stromal protection. Interestingly, expression of the esterase in normal fibroblasts or endothelial cells had no effect on their survival. Transplanted mice induced for expression of the O-acetylesterase in the ALL cells exhibited a reduction of leukemia to minimal cell numbers and significantly increased survival. This demonstrates that Neu5Ac 9-O-acetylation is essential for survival of these cells and suggests that Neu5Ac de-O-acetylation could be used as therapy to eradicate drug-resistant ALL cells.

The Role of the Interaction between Fe(III) and Cell Surface in the Accumulation of 67Ga by Tumor Cells

1991 ◽  
Vol 30 (06) ◽  
pp. 290-293 ◽  
Author(s):  
P. Maleki ◽  
A. Martinezi ◽  
M. C. Crone-Escanye ◽  
J. Robert ◽  
L. J. Anghileri
Keyword(s):  
Cell Surface ◽  
Tumor Cells ◽  
Ionic Composition ◽  
Iron Complex ◽  
Iron Binding ◽  
Complex Time ◽  
Interaction Product ◽  
Thermodynamic Constant ◽  
Number Of Cells

The study of the interaction between complexed iron and tumor cells in the presence of 67Ga-citrate indicates that a phenomenon of iron-binding related to the thermodynamic constant of stability of the iron complex, and a hydrolysis (or anion penetration) of the interaction product determine the uptake of 67Ga. The effects of various parameters such as ionic composition of the medium, nature of the iron complex, time of incubation and number of cells are discussed.

Ligand Design for Specific MHC Class I Molecules on the Cell Surface

2020 ◽  
Author(s):  
Xizheng Sun ◽  
Reika Tokunaga ◽  
Yoko Nagai ◽  
Ryo Miyahara ◽  
Akihiro Kishimura ◽  
...  
Keyword(s):  
Cell Surface ◽  
Mhc Class I ◽  
Targeted Delivery ◽  
Peptide Ligands ◽  
Class I ◽  
Class I Mhc ◽  
Mhc I ◽  
Histocompatibility Complex ◽  
High Binding Affinity ◽  
Mhc Class I Molecules

<p><a></a><a></a><a>We have validated that ligand peptides designed from antigen peptides could be used for targeting specific major histocompatibility complex class I (MHC-I)</a> molecules on cell surface. To design the ligand peptides, we used reported antigen peptides for each MHC-I molecule with high binding affinity. From the crystal structure of the peptide/MHC-I complexes, we determined a modifiable residue in the antigen peptides and replaced this residue with a lysine with an ε-amine group modified with functional molecules. The designed ligand peptides successfully bound to cells expressing the corresponding MHC-I molecules via exchange of peptides bound to the MHC-I. We demonstrated that the peptide ligands could be used to transport a protein or a liposome to cells expressing the corresponding MHC-I. The present strategy may be useful for targeted delivery to cells overexpressing MHC-I, which have been observed autoimmune diseases.</p>

Role of Natriuretic Peptide Receptor Type C in Dahl Salt-Sensitive Hypertensive Rats

Hypertension ◽  
1997 ◽  
Vol 30 (2) ◽  
pp. 177-183 ◽  
Author(s):  
Miki Nagase ◽  
Katsuyuki Ando ◽  
Takeshi Katafuchi ◽  
Akira Kato ◽  
Shigehisa Hirose ◽  
...  
Keyword(s):  
Natriuretic Peptide ◽  
Receptor Type ◽  
Natriuretic Peptide Receptor ◽  
Hypertensive Rats ◽  
Peptide Receptor ◽  
Type C
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