http://www.worldofteaching.com/
http://ugc-inno-nehu.com/links_from_web.html
FT NMR WORKSHOP/===/ S.A.I.F./===/
NEHU/==/ Shillong
INTRODUCTORY
LECTURE
S.ARAVAMUDHAN
http://aravamudhan-s.ucoz.com/
http://www.ugc-inno-nehu.com
Glycine
L-alanine
http://riodb01.ibase.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi
SDBS-13C NMR
L-alanylglycine
SDBS-13C NMR
glycylglycine
Glycine
Glycylglycylglycine
glycylglycylglycylglycine
Proton NMR spectra also have similar trends
http://www.bmrb.wisc.edu/ref_info/wuthrich_chem_shift.txt
TEXT COPY
Bundi, A. and Wuthrich, K., "1H-NMR Parameters of the Common
Amino Acid Residues Measured in Aqueous Solutions of the Linear
Tetrapeptides H-Gly-Gly-X-L-Ala-OH," Biopolymers 18, 285-297
(1979). ; 2 ;
Richarz, R. and Wuthrich, K., "Carbon-13 NMR Chemical Shifts of
the Common Amino Acid Residues Measured in Aqueous Solutions of
the Linear Tetrapeptides H-Gly-Gly-X-L-Ala-OH," Biopolymers 17,
2133-2141 (1978). ; 3 ; Wuthrich, K. "NMR in Biological Research:
Peptides and Proteins," North Holland, Amsterdam (1975).
The values have ben tabulated for all the 20 amino acids
http://www.bmrb.wisc.edu/ref_info/wuthrich_chem_shift.txt
Click HERE for copy
Similarly for all the 20 amino acids characteristics in NMR
are enlisted
The fist step in sequential assignment is the identification of certain amino acids,
with a characteristic pattern of cross signals, i.e. of glycine, alanine, threonine,
valine, leucine and isoleucine.
The HSQC Experiment:
double resonance
It correlates the
nitrogen atom of an
NHx group with the
directly attached
proton.
Each signal in a HSQC
spectrum represents a
proton that is bound to
a nitrogen atom.
Thus, dipeptides are identified and subsequently prolonged to
oligopeptides by the search for further sequential contacts.
Some time along the line these oligopeptides can be placed at
a unique place in the primary structure by comparison with the
amino acid sequence of the protein - they are sequentially
assigned.
The chain of sequential connectivites is interrupted by proline
residues because these have no amide proton. Therefore, no
HN(i)-Halpha(i-1) cross signal can be observed. However, if the
proline (i) is in its trans conformation, the sequential HN(i-1)Hdelta(i) and Halpha(i-1)-Hdelta(i) cross signals can be observed.
Another problem is, that this approach of sequential
assignment breaks down for larger proteins because the vast
number of signals leads to spectral overlap which hinders the
identification of signals.
Organic Chemistry Info
http://www.chem.wisc.edu/areas/organic/index-chem.htm
Biomolecular Structure
http://www.bmrb.wisc.edu/www/
Protein NMR - A Practical Guide
http://www.protein-nmr.org.uk/
Assigned Chemical Shift Outliers for 'Diamagnetic' Proteins
http://www.bmrb.wisc.edu/data_access/sel_outlier_selection_grid.html
data_Standard_amino_acid_chemical_shifts_pentapeptide_GGXGG_in_Urea
http://www.bmrb.wisc.edu/ref_info/pentapeptide.tbl
Bundi, A. and Wuthrich, K., "1H-NMR Parameters of the Common Amino Acid Residues Measured in Aqueous Solution
s of the Linear Tetrapeptides H-Gly-Gly-X-L-Ala-OH," Biopolymers 18, 285-297 (1979).
http://www.bmrb.wisc.edu/ref_info/wuthrich_chem_shift.txt
Spectral Data Base: 1H, 13C, IR, Raman, Mass
http://riodb01.ibase.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi
http://www.bmrb.wisc.edu/www/structur.html
http://www.cryst.bbk.ac.uk/PPS2/projects/schirra/html/assign.htm
http://www.protein-nmr.org.uk/assignment_theory.html
http://www.pnas.org/content/104/23/9615.full
The Internet references are mainly to provide a quick
reinforcement to the materials delivered at this woekshop,
for an immediate follow up soon after the concluding
session of the workshop.
The purpose should be to make use of the NMR technique
with a better authenticity by acquring necessary copyright
permissions and based on ones own experiences by gaining
confidence by consulting the original publications of
standrad authors by standard publications. Even such
resources are available from the appropriate portals with
proper registration and subscriptions.