A biophysical and structural study of two chitinases from Agave tequilana and their potential role as defense proteins.

Sierra-Gómez Y, Rodríguez-Hernández A, Cano-Sánchez P, Gómez-Velasco H, Hernández-Santoyo A, Siliqi D, Rodríguez-Romero A, FEBS J (2019) Europe PMC

SASDDA6 – Class I chitinase 2 from Agave tequilana

Chitinase 2
MWexperimental 32 kDa
MWexpected 32 kDa
VPorod 49 nm3
log I(s) 1.07×102 1.07×101 1.07×100 1.07×10-1
Chitinase 2 small angle scattering data  s, nm-1
ln I(s)
Chitinase 2 Guinier plot ln 1.07×102 Rg: 2.4 nm 0 (2.4 nm)-2 s2
(sRg)2I(s)/I(0)
Chitinase 2 Kratky plot 1.104 0 √3 sRg
p(r)
Chitinase 2 pair distance distribution function Rg: 2.5 nm 0 Dmax: 9.8 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Chitinase 2 DAMMIF model
Synchrotron SAXS data from solutions of Chitinase 2 from Agave tequilana in MES 50 mM, pH 6, were collected on the BL4-2 beam line at the Stanford Synchrotron Radiation Lightsource (SSRL; Stanford, CA, USA) using a Rayonix MX225-HE detector at a sample-detector distance of 1.8 m and at a wavelength of λ = 0.1127 nm (l(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). Solute concentrations ranging between 0.5 and 7.5 mg/ml were measured at 15°C. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted. The low angle data collected at lower concentration were merged with the highest concentration high angle data to yield the final composite scattering curve.

Number of frames = UNKNOWN

Chitinase 2 (ChiAt2)
Mol. type   Protein
Organism   Agave tequilana
Olig. state   Monomer
Mon. MW   31.9 kDa
Sequence   FASTA