Nikolai N. Sluchanko

6 Questions 15 Answers 0 Followers

Questions related from Nikolai N. Sluchanko

How to export chromatograms and spectra from diode array detector data?

The DAD data are collected into a .run file during an HPLC run followed by a Varian Prostar 335 detector. The file cannot be merely opened via a notepad and the question is how to extract all the...

04 April 2019 5,836 3 View

An all-alpha helical protein changes a 208/222 nm ratio on its far UV CD spectrum. Any suggestions?

Some modification changes the CD spectrum of a small helical protein so that the 208nm band becomes more pronounced relative to the 222 band. Are there any reliable interpretations? Paper...

07 July 2017 4,038 1 View

Why can a protein elute from a SEC column (@150 mM NaCl) later than expected for its monomer?

Theoretical mass is 25 kDa, SDS-PAGE shows 26 kDa, no presence of degradation products. The SEC profile shows the major, very symmetrical peak at ~20 kDa. Why could this be? Unspecific interaction...

08 August 2016 8,123 17 View

Why does maltose binding protein (MBP) tag increase fusion protein expression levels in E.coli?

N-terminal MBP increases not only solubility of the fusion constructs but also their expression levels. Why?

10 October 2015 1,286 7 View

Any specific (non-obvious) points in purifying his-tagged protein with 12 histidines comparing with that with 6 histidines?

The his tag is of 12 His residues at the C-terminus of the protein without a linker. So, what should be considered besides points of the typical protocol? Higher imidazole concentration of the...

02 February 2015 9,203 4 View

Has anyone tried to add TMAO (or PEG20K) in gels for electrophoretic separation of proteins (non-denaturing conditions)?

The idea is to visualize high-order oligomers of a protein which can self-associate but normally exists as small oligomers. Is it OK to use native-PAGE and gels containing TMAO? Which TMAO...

04 April 2014 1,151 0 View