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Structure and Sialyllactose Binding of the Carboxy-Terminal Head Domain of the Fibre from a Siadenovirus, Turkey Adenovirus 3.

Singh AK, Berbís MÁ, Ballmann MZ, Kilcoyne M, Menéndez M, Nguyen TH, Joshi L, Cañada FJ, Jiménez-Barbero J, Benkő M, Harrach B, van Raaij MJ - PLoS ONE (2015)

Bottom Line: The carboxy-terminal region of its fibre does not have significant sequence similarity to any other adenovirus fibre heads of known structure.It binds slightly more strongly to the avirulent form.We propose that, in vivo, the TAdV-3 fibre may bind a sialic acid-containing cell surface component.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain.

ABSTRACT
The virulent form of turkey adenovirus 3 (TAdV-3), also known as turkey hemorrhagic enteritis virus (THEV), is an economically important poultry pathogen, while the avirulent form is used as a vaccine. TAdV-3 belongs to the genus Siadenovirus. The carboxy-terminal region of its fibre does not have significant sequence similarity to any other adenovirus fibre heads of known structure. Two amino acid sequence differences between virulent and avirulent TAdV-3 map on the fibre head: where virulent TAdV-3 contains Ile354 and Thr376, avirulent TAdV-3 contains Met354 and Met376. We determined the crystal structures of the trimeric virulent and avirulent TAdV-3 fibre head domains at 2.2 Å resolution. Each monomer contains a beta-sandwich, which, surprisingly, resembles reovirus fibre head more than other adenovirus fibres, although the ABCJ-GHID topology is conserved in all. A beta-hairpin insertion in the C-strand of each trimer subunit embraces its neighbouring monomer. The avirulent and virulent TAdV-3 fibre heads are identical apart from the exact orientation of the beta-hairpin insertion. In vitro, sialyllactose was identified as a ligand by glycan microarray analysis, nuclear magnetic resonance spectroscopy, and crystallography. Its dissociation constant was measured to be in the mM range by isothermal titration calorimetry. The ligand binds to the side of the fibre head, involving amino acids Glu392, Thr419, Val420, Lys421, Asn422, and Gly423 binding to the sialic acid group. It binds slightly more strongly to the avirulent form. We propose that, in vivo, the TAdV-3 fibre may bind a sialic acid-containing cell surface component.

No MeSH data available.


Related in: MedlinePlus

Thermal stability assay of virulent and avirulent TAdV-3 fibre head proteins.The relative fluorescence emission intensity (RFU, arbitrary unit) is plotted as a function of the temperature. Data for virulent (open circles) and avirulent (filled squares) TAdV-3 fibre head proteins are shown. A melting temperature of around 80°C was estimated for both proteins.
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pone.0139339.g002: Thermal stability assay of virulent and avirulent TAdV-3 fibre head proteins.The relative fluorescence emission intensity (RFU, arbitrary unit) is plotted as a function of the temperature. Data for virulent (open circles) and avirulent (filled squares) TAdV-3 fibre head proteins are shown. A melting temperature of around 80°C was estimated for both proteins.

Mentions: Each TAdV-3 fibre head monomer has a surface area of 9.4 x 103 Å2, of which 2.6 x 103 Å2 (27%) is buried in the trimer. The calculated energy released upon trimer formation is around 60 kcal/mol and a salt bridge is formed between Glu401 and Arg390 of a neighbouring monomer. These properties resemble those of other adenovirus and reovirus fibre heads, suggesting that the stability of the trimer is comparable. As for other trimeric fibre heads, we observed trimers in denaturing gel electrophoresis if the sample was not previously boiled [66]. The melting temperatures of both the virulent and avirulent forms of the protein are 80°C at pH 6 (Fig 2), which indicates the protein is very stable [67].


Structure and Sialyllactose Binding of the Carboxy-Terminal Head Domain of the Fibre from a Siadenovirus, Turkey Adenovirus 3.

Singh AK, Berbís MÁ, Ballmann MZ, Kilcoyne M, Menéndez M, Nguyen TH, Joshi L, Cañada FJ, Jiménez-Barbero J, Benkő M, Harrach B, van Raaij MJ - PLoS ONE (2015)

Thermal stability assay of virulent and avirulent TAdV-3 fibre head proteins.The relative fluorescence emission intensity (RFU, arbitrary unit) is plotted as a function of the temperature. Data for virulent (open circles) and avirulent (filled squares) TAdV-3 fibre head proteins are shown. A melting temperature of around 80°C was estimated for both proteins.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4587935&req=5

pone.0139339.g002: Thermal stability assay of virulent and avirulent TAdV-3 fibre head proteins.The relative fluorescence emission intensity (RFU, arbitrary unit) is plotted as a function of the temperature. Data for virulent (open circles) and avirulent (filled squares) TAdV-3 fibre head proteins are shown. A melting temperature of around 80°C was estimated for both proteins.
Mentions: Each TAdV-3 fibre head monomer has a surface area of 9.4 x 103 Å2, of which 2.6 x 103 Å2 (27%) is buried in the trimer. The calculated energy released upon trimer formation is around 60 kcal/mol and a salt bridge is formed between Glu401 and Arg390 of a neighbouring monomer. These properties resemble those of other adenovirus and reovirus fibre heads, suggesting that the stability of the trimer is comparable. As for other trimeric fibre heads, we observed trimers in denaturing gel electrophoresis if the sample was not previously boiled [66]. The melting temperatures of both the virulent and avirulent forms of the protein are 80°C at pH 6 (Fig 2), which indicates the protein is very stable [67].

Bottom Line: The carboxy-terminal region of its fibre does not have significant sequence similarity to any other adenovirus fibre heads of known structure.It binds slightly more strongly to the avirulent form.We propose that, in vivo, the TAdV-3 fibre may bind a sialic acid-containing cell surface component.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain.

ABSTRACT
The virulent form of turkey adenovirus 3 (TAdV-3), also known as turkey hemorrhagic enteritis virus (THEV), is an economically important poultry pathogen, while the avirulent form is used as a vaccine. TAdV-3 belongs to the genus Siadenovirus. The carboxy-terminal region of its fibre does not have significant sequence similarity to any other adenovirus fibre heads of known structure. Two amino acid sequence differences between virulent and avirulent TAdV-3 map on the fibre head: where virulent TAdV-3 contains Ile354 and Thr376, avirulent TAdV-3 contains Met354 and Met376. We determined the crystal structures of the trimeric virulent and avirulent TAdV-3 fibre head domains at 2.2 Å resolution. Each monomer contains a beta-sandwich, which, surprisingly, resembles reovirus fibre head more than other adenovirus fibres, although the ABCJ-GHID topology is conserved in all. A beta-hairpin insertion in the C-strand of each trimer subunit embraces its neighbouring monomer. The avirulent and virulent TAdV-3 fibre heads are identical apart from the exact orientation of the beta-hairpin insertion. In vitro, sialyllactose was identified as a ligand by glycan microarray analysis, nuclear magnetic resonance spectroscopy, and crystallography. Its dissociation constant was measured to be in the mM range by isothermal titration calorimetry. The ligand binds to the side of the fibre head, involving amino acids Glu392, Thr419, Val420, Lys421, Asn422, and Gly423 binding to the sialic acid group. It binds slightly more strongly to the avirulent form. We propose that, in vivo, the TAdV-3 fibre may bind a sialic acid-containing cell surface component.

No MeSH data available.


Related in: MedlinePlus