2012 -
Download
1 / 30

2012 - 3D Structures of Biological Macromolecules - PowerPoint PPT Presentation


  • 103 Views
  • Uploaded on

2012 - 3D Structures of Biological Macromolecules Part 2: A Case Study in Structural Bioinformatics – C-H…  -Interactions in Proteins. Jürgen Sühnel [email protected] Leibniz Institute for Age Research, Fritz Lipmann Institute, Jena Centre for Bioinformatics Jena / Germany.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' 2012 - 3D Structures of Biological Macromolecules' - harley


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  • 2012 -

  • 3D Structuresof Biological Macromolecules

  • Part 2: A Case Study in Structural Bioinformatics –

  • C-H…-Interactions in Proteins

Jürgen Sühnel

[email protected]

Leibniz Institute for Age Research, Fritz Lipmann Institute,

Jena Centre for Bioinformatics

Jena / Germany

Supplementary Material: www.fli-leibniz.de/www_bioc/3D/


C-H...-Interactions in Proteins

-system

C

|

H


C-H...-Interactions:Well-known in smallmolecules

Kooijman et al, Acta Cryst. C. 2000, 56, 481-483

Benzene and analogous compounds

dissolve exothermically in chlorofom.

M. Tamres.

Aromatic compounds as donor molecules in hydrogen bonding.

J. Am. Chem. Soc.1952, 74, 3375-3378.


C-H...-Interactions in Proteins

Exceptfor a fewreports on theoccurrenceof

C-H...-interactions in selectedstructures

therehasbeennosystematicstudyforproteins.


C-H...-Interactions in Proteins:Database

Crystal structures with a resolution of 3.0 Å or better

R-factor: 25% or lower

Minimal chain length: 40

Maximum amino acid identity: 25%

PISCES web server


C-H...-Interactions in Proteins


C-H...-Interactions in Proteins


C-H...-Interactions in Proteins


C-H...-Interactions in Proteins: GeometricalSelection

Distance C-X< 4.5 Å

Distance Hp-X < 1.2 Å (aro), 1.0 Å (non-aro)

Angle C-H-X > 120 º


C-H...-Interactions in Proteins: Aims

Analysis of C-H...-interactionsoccurring in proteins

  • Whichinteractionssatisfythegeometricalcriteriaadopted?

  • Whichdonoratomtypesandwhich -systemsareinvolved ?

  • Where in proteins do C-H... -interactionsoccur ?

  • Are thereanysecondarystructureandneighbourhoodrelations ?


C-H...-Interactions in Proteins

dCX fraction

< 4.0 Å 69%

< 4.1 Å 78%

< 4.2 Å 86%

< 4.3 Å 92%

< 4.4 Å 96%

dCX

3.74 – 3.93 Å


C-H...-Interactions in Proteins

Donor / acceptor Aro- Am- Ac- Arg- Total

C-H 1,832 437 568 712 3,549

(1,01) (0,34) (0,31) (0,99)

Cali-H14,487 2,638 3,861 2,584 23,570

(1,95) (0,51) (0,52) (0,88)

Caro-H2,687 361 608 312 3,968

(3,43) (0,66) (0,77) (1,0)

Total 19,006 3,436 5,037 3,608 31,087

Donors

C-H - total number of aa plus number of Gly

Cali-H - all alipahtic C-H groups except for C-H

Caro-H - all aromatic C-H groups

Acceptors

Aro - aromatic ring His, Phe, Trp, Tyr

Am - amide group Asn, Gln

Ac - carboxylate group Asp, Glu

Arg - amidinium group Arg

Non-redundant database

of 1154 protein chains with 285,794 amino acids


C-H...-Interactions in Proteins


C-H...-Interactions in Proteins


The 15 interactions identified

occur in all parts of the protein.

Some of them are completely buried

and others are partially exposed

to the solvent.

B-eye-lens-crystallin (1amm, 1.2 Å)


Interactions are referred to as local

if the sequence distance is smaller

than 10.

41% of C-H...-interactions are local.


C-H...-Interactions in Proteins

  • 63% of this interaction type are local.

  • 89% of the –3 peak interactions occur in helices.

  • This interaction may be a major stabilizing element

  • in -helices.




C-H...-Interactions in Proteins

M. Brandl, M. S. Weiss, A. Jabs, J. Sühnel, R. Hilgenfeld.

C-H... interactions in proteins.

J. Mol. Biol.2001, 307, 357-377


C-H...-Interactions in Proteins

C-H... and C-H...O/N interactions are opportunistic ???


C-H...-Interactions in Proteins

  • Most prominent are interactions between

    aliphatic or aromatic C-H donors and aromatic acceptors.

  • About three quarters of all Trp-rings, half of all Phe- and Tyr-rings

    and a quarter of His-rings are involved as acceptors in

    C-H...-interactions.

  • On the donor side there is a preference for aromatic C-H groups,

    for prolines and for the long extended aliphatic amino acids

    Lys, Arg and Met.

  • C-H...-interactions involving aromatic groups

    either as donor or as acceptor are found mostly in the interior

    of the protein. The more hydrophilic the participating groups are,

    the closer to the surface are the interactions located.

  • It is likely that C-H...-interactions contribute significantly to

    overall protein stability.

M. Brandl, M. S. Weiss, A. Jabs, J. Sühnel, R. Hilgenfeld.

C-H... interactions in proteins.

J. Mol. Biol.2001, 307, 357-377.


More Hydrogen Bonds forthe (Structural) Biologist


More Hydrogen Bonds forthe (Structural) Biologist

A general concept of hydrogen bonding in proteins is emerging.

This concept involves not only N-H and O-H donor groups, but also C-H,

and not only N and O as acceptor groups, but also -systems.

We postulate that the incorporation of the entirety of these

interactions leads to a more complete description of protein structures.

M. S. Weiss, M. Brandl, J. Sühnel, D. Pal, R. Hilgenfeld.

More hydrogen bonds for the (structural) biologist.

Trends Biochem. Sci. 2001, 26, 521-523.


More Hydrogen Bonds forthe (Structural) Biologist

M. S. Weiss, M. Brandl, J. Sühnel, D. Pal, R. Hilgenfeld.

More hydrogen bonds for the (structural) biologist.

Trends Biochem. Sci. 2001, 26, 521-523.


More Hydrogen Bonds forthe (Structural) Biologist

phospholipase C (PDB code: 1ah7)

“Classical” N-H...O

(helix192-204)

C-H...O

(LYS153-Val149)

C1-H...

(Trp238-Phe94)

N-H...

(Ser63-Tyr61)

M. S. Weiss, M. Brandl, J. Sühnel, D. Pal, R. Hilgenfeld.

More hydrogen bonds for the (structural) biologist.

Trends Biochem. Sci. 2001, 26, 521-523.


More Hydrogen Bonds forthe (Structural) Biologist

  • Incorporation of the results obtained in

  • structure prediction and refinement programs

  • Identification of examples for the structural and functional relevance of

  • the new interaction types

M. S. Weiss, M. Brandl, J. Sühnel, D. Pal, R. Hilgenfeld.

More hydrogen bonds for the (structural) biologist.

Trends Biochem. Sci. 2001, 26, 521-523.


ad