"Median and Mean Xylanase Data" 
Experimental SAS Curve 


Experimental Mass
21,000 Da 
Experimental Details for BID: 1XYNTP 
Experiment ID: 78

Collected at: ALS BL 12.3.1 
Contributors:
Rambo, RP


High noise dataset used to demonstrate propagation of error and influence of noise on Chisquare. 10 independent, 5 sec exposures of sizeexclusion chromatography purified xylanase collected to qmax = 0.31 (Å1) at ~1.4 mg/ml. Median SAS curve is the median intensity for each I(q). Intensities and associated uncertainties that are taken as the median best approximate the average I(q) without signal enhancement from averaging. Model fits with CRYSOL to PDB: 1REF produced a chi2 of 0.995 and chi2free of 1.66. Average SAS curve is the average intensity for each I(q). Model fits with CRYSOL produced a conventional chi2 of 1.00 and chi2free of 1.56.

single concentration. Sample was divided into 10 separate wells with 10 different buffers.






D_{max} → 43 Å





Guinier R_{g} → 16.74 Å
Real Space R_{g} → 15.96 Å

The Guinier plot is used to estimate the radius of gyration, R_{g}, which is taken from the slope of a line observed at low scattering angles (typically in the range where q* R_{g} < 1.3). This should be in reasonable agreement with the real space R_{g}.


 


The Kratky plot can be used to visually assess the degree of "unfoldedness" of a protein or RNA sample.
The plot of a wellbehaved folded protein approaches the baseline at high q values creating a parabolic shape.


 


The red line is the calculated SAXS profile from a PDB model scaled to the experimental SAXS curve (cyan). The two curves agree with a Chi^{2} of 1.6.


Additional Experimental Details 
Title Median and Mean Xylanase Data 
Description High noise dataset used to demonstrate propagation of error and influence of noise on Chisquare. 10 independent, 5 sec exposures of sizeexclusion chromatography purified xylanase collected to qmax = 0.31 (Å1) at ~1.4 mg/ml. Median SAS curve is the median intensity for each I(q). Intensities and associated uncertainties that are taken as the median best approximate the average I(q) without signal enhancement from averaging. Model fits with CRYSOL to PDB: 1REF produced a chi2 of 0.995 and chi2free of 1.66. Average SAS curve is the average intensity for each I(q). Model fits with CRYSOL produced a conventional chi2 of 1.00 and chi2free of 1.56.

Publication Accurate assessment of mass, models and resolution by smallangle scattering. Nature. 2013 Apr 25;496(7446):47781.

Contributors
Rambo, RP

Genomics and Proteomics
The experiment is
composed of a single gene/ORF
Abbreviated name: XYNAT1
Annotation:
Xylanase. sequence. from. 1REF
ETIQPGTGYN
NGYFYSYWND
GHGGVTYTNG
PGGQFSVNWS
NSGNFVGGKG
WQPGTKNKVI
NFSGSYNPNG
NSYLSVYGWS
RNPLIEYYIV
ENFGTYNPST
GATKLGEVTS
DGSVYDIYRT
QRVNQPSIIG
TATFYQYWSV
RRNHRSSGSV
NTANHFNAWA
QQGLTLGTMD
YQIVAVEGYF
SSGSASITVS



category  amino acid composition(%) 
Hydrophobic  I(4.7) V(7.4) L(2.6) M(0.5) A(3.7) G(14.2) P(3.7) 
Aromatic  F(4.2) W(3.2) Y(8.9) 
Hydrophilic  R(3.2) K(2.1) E(2.6) D(2.1) Q(4.7) N(10.5) H(1.6) S(11.6) T(8.4) C(0.0) 


