Polarized Raman spectra of L-arginine hydrochloride monohydrated single crystal

Abstract

Polarized Raman spectra of L-arginine hydrochloride monohydrated single crystal in nine different scattering geometries of the two irreducible representations of factor group C 2 were studied at room temperature. The experimental wavenumber values are compared with those obtained from ab-initio calculation and the assignment of the Raman bands to the respective molecular vibrations is also given. Finally, a discussion related to a previously reported phase transition undergone by L-arginine hydrochloride monohydrated single crystal at low temperature is furnished.

Role of Phe‐D5 isotopically labeled analogues of bradykinin on elucidation of its adsorption mode on Ag, Au, and Cu electrodes. Surface‐enhanced Raman spectroscopy studies

“…In the spectra in Fig. the Raman signals assignable to the Arg residue(s) (Arg 1 /Arg 9 ) vibrations (~1657 [ν(C = N)], ~1472 [δ(CH 2 )], ~1449 [δ(NH)], ~1090 [ν s (C − N)/δ(NH 2 )], ~876 [δ(CH 2 )], and ~842 cm −1 [δ(NH)]) are medium‐weak enhanced . The influence of the Pro residue and amide bonds oscillations on the BK Raman spectra could not be excluded because the ~1472 [amide IIp marker of relatively strong prolyl C = O interactions], ~1449 [amide IIp marker of non‐hydrogen‐bonded C = O acceptor], ~1249 [amide III], ~876 [ρ r (CH 2 ) ring ], ~736 [ρ r (CH 2 ) ring ], and ~665 cm −1 [amide V]) spectral features are characteristic of the tertiary amide bond and Pro ring .…”

A vibrational and conformational characterization of arginine at different pH values investigated using Raman spectroscopy combined with DFT calculations

“…A number of theoretical and experimental studies have been performed on amino acids in aqueous solutions . Bonaccorsi et al explored the conformational energies of ZW and neutral forms of glycine (Gly) at different levels of theory.…”

“…In this regard, various continuum models have been developed and proven to be useful tools for modeling the solute–solvent interaction. The continuum‐based models have been particularly successful in the interpretation of the vibrational spectra of the ZW form of amino acids in solution . Poopari et al performed an experimental and theoretical study of the hydrogen bond interaction of leucine (Leu) with water molecules at different pH values.…”

“…In addition to the studies discussed earlier, recently, there are some experimental and theoretical studies on Arg, which have been performed at different pH values . However, to the best of our knowledge, a detailed combined study on the vibrational and conformational characterization of Arg at different protonation states (pH values) based on Raman spectroscopic results, DFT calculations (explicit and implicit), and thermodynamical analysis is still lacking in the literature.…”

The Peptide AmPep1 Derived from Amaranth Recognizes the Replication Hairpin of TYLCV Disturbing Its Replication Process in Host Plants

“…Chemical interaction between the two biomolecules also modifies the vibrational mode of the dioxyphosphate group in the DNA structure, leading to a shift from 1092 to 1096 cm –1 , which can be attributed to the electrostatic interaction between the negatively charged PO 2– group with positively charged amino acid side chains such as Arg or Lys. ,, This interaction is reflected by the decreased band intensity of the NH 3 + deformation mode of the peptide at 1131 cm –1 . In addition, other characteristic vibrational modes of DNA are affected, for example ring stretching of G and C bases is shifted from 1253 to 1257 cm –1 ; C–N stretching vibrations of T, A, and G are shifted from 1369 to 1374 cm –1 ; the C–N stretching vibration in C8–N7 bonds of G shifts from 1480 to 1485 cm –1 ; and the vibrational modes of the ring moieties of purine bases shift from 1574 to 1578 cm –1 , which are the major DNA interaction markers. , These results support the strong ring interaction between the aromatic systems of A and G with the indole group of Trp, mainly through π–π type interactions .…”