Can histidine H-bond with itself?

[artsydoc]

It seems like an N-H group in histadine could act as both hydrogen bond donor and acceptor, similarly to an O-H in water. Anyone have any thoughts on it? Thanks!

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[Woland]

IMHO: I think it depends on particular dipole and stereochemistry. However, despite the fact that the molecule of imidazole has a very strong dipole, most of the (-) charge is resonated on the non-H nitrogen. The N-H bond is much less polar than the O-H bond in water, due to lone-pair of the H-bonded nitrogen participating in the aromaticity. Additionally, the vector of the bond's dipole points in the center of the imidazole ring.
So, I would venture a guess that in terms of the fraction of H-bonds, this one will be small. Most will be H-bonds from NH2 and COOH.

[Edit] but I am a lawyer not a chem-major.

 

[Mithril]

The -NH in the R group of histidine can act as a donor, but not as an acceptor due to resonance. Histidine's long R group and the shape of any single amino acid for that matter makes it extremely unlikely for intra-amino acid hydrogen bonding.