L-proline

Proline (IUPAC-IUBMB abbreviation: Pro and P) is an α-amino acid, and its L enantiomer is one of the 22 proteinogenic amino acids. It is encoded on messenger RNAs by the codons CCU, CCC, CCA, and CCG. Unique among proteinogenic amino acids, proline features a secondary amine instead of a primary one, resulting in a distinct geometry that tends to disrupt secondary protein structures such as α-helices and β-sheets.

Proline contributes to the formation of non-polar residues that, when polymerized, can generate various types of proteins within the polyproline family. The presence of multiple proline residues can lead to the formation of a proline helix, as observed in the structure of collagen, a fibrous protein that constitutes a major component of connective tissues in the body.

The proline ring is nearly planar, a characteristic that can be demonstrated by examining the bond angles within the proline ring. This unique geometry and behavior make proline a critical player in the structural and functional properties of proteins, contributing to their diverse and intricate architectures.

MBS405310 | cis-4-Hydroxy-L-Proline
MBS405360 | L-Proline
MBS545500 | L-PROLINE
MBS652697 | RPMI 1640 w/o L-Proline (Powder)
MBS1445394 | Recombinant Rhizobium loti L-proline cis-4-hydroxylase (mlr6283)
MBS6014631 | Biocytin-L-proline
MBS6018981 | cis-4-Hydroxy-L-proline
MBS6026146 | Hydroxy-L-Proline (non-animal)
MBS6030077 | L-Proline (non-animal)
MBS6044621 | Captopril (([2S]-N-[3-Marcapto-2-methylpropionyl]-L-proline)
MBS6050128 | Hydroxy-L-Proline
MBS6053708 | (4S)-4-(Phenylthio)-L-proline Hydrochloride
MBS6053900 | N-Nitroso-L-proline
MBS6063025 | t-Butyl-N-carbobenzyloxy-L-aspartyl-L-proline
MBS6066576 | (4R)-1-Methyl-4-propyl-L-proline Hydrochloride
MBS6071673 | (4S)-4-Cyclohexyl-L-proline Hydrochloride
MBS6075850 | L-Alanyl-L-proline tert-Butyl Ester
MBS6096254 | Biocytin-N-(t-boc)-L-proline
MBS6098783 | L-Proline Methyl Ester Hydrochloride
MBS6101132 | t-Butyl-L-aspartyl-L-proline
  1. Structural Impact: Proline's distinct geometry introduces kinks and turns in the peptide chain, affecting the overall structure and conformation of proteins. It serves as a key component in various structural motifs, contributing to the stability and flexibility of protein structures.
  2. Biological Significance: Beyond its structural role, proline is involved in numerous biological processes. It participates in protein-protein interactions, signaling pathways, and the regulation of enzyme activity, underscoring its significance in diverse cellular functions.
  3. Post-Translational Modifications: Proline undergoes various post-translational modifications, including hydroxylation, glycosylation, and phosphorylation. These modifications can influence protein function and localization, contributing to the dynamic regulation of cellular processes.
  4. Role in Collagen Formation: Proline is a major component of collagen, the most abundant protein in mammals. Collagen's unique triple-helical structure relies on proline's rigid conformation, providing strength and stability to connective tissues such as skin, tendons, and bones.
  5. Polyproline Helices: The presence of multiple proline residues in certain proteins can induce the formation of polyproline helices, which play crucial roles in protein-protein interactions, signaling cascades, and cytoskeletal dynamics, among other functions.


Accession Number : KLM0000308 This work is released into the public domain; please see our release statement.

l-proline-3d.gif

Synonyms :

 

  • L-PROLINE
  • Pro
  • P

 

Config Rule :

 

% 'L-proline'


config('L-proline',[
        ring([
                (nit(1,hyd&&hyd;),down)~,
                (car(1,carboxyl(2)&&hyd;),left)~,
                methandiyl(3),
                methandiyl(4),
                (methandiyl(5),left)~])]).

Smiles String :

 

[C@1H]-1([N@2H2+][C@2H2][C@2H2][C@2H2]-1)[C](=[O])[O-]

'L-proline'

Fischer Diagram :

 

Terminal :

% 'L-proline'

c(1,12,(0,chiral))-[c(3,left)~,c(2,right)~,n(1,up)~,h(3,down)~],
c(2,12,(0,nonchiral))-[c(1,left)~,o(1,nil)?,o(2,nil)?],
c(3,12,(0,nonchiral))-[c(4,left)~,c(1,right)~,h(4,up)~,h(5,down)~],
c(4,12,(0,nonchiral))-[c(5,left)~,c(3,right)~,h(6,up)~,h(7,down)~],
c(5,12,(0,nonchiral))-[n(1,left)~,c(4,right)~,h(8,up)~,h(9,down)~],
h(1,1,(0,nonchiral))-[n(1,right)~],
h(2,1,(0,nonchiral))-[n(1,down)~],
h(3,1,(0,nonchiral))-[c(1,up)~],
h(4,1,(0,nonchiral))-[c(3,down)~],
h(5,1,(0,nonchiral))-[c(3,up)~],
h(6,1,(0,nonchiral))-[c(4,down)~],
h(7,1,(0,nonchiral))-[c(4,up)~],
h(8,1,(0,nonchiral))-[c(5,down)~],
h(9,1,(0,nonchiral))-[c(5,up)~],
n(1,14,(1,nonchiral))-[h(1,left)~,c(5,right)~,h(2,up)~,c(1,down)~],
o(1,16,(-5.0E-01,nonchiral))-[c(2,nil)?],
o(2,16,(-5.0E-01,nonchiral))-[c(2,nil)?]

The Terminals for all the Config Rules are in Prolog Definite Clause Grammar (DCG) form.They can be checked in the Manual here.

The compound's PDB file can be seen here.