In-depth correlation analysis demonstrates that 4-hydroxyproline at the Yaa position of Gly-Xaa-Yaa repeats dominantly stabilizes collagen triple helix

Yuki Taga; Keisuke Tanaka; Shunji Hattori; Kazunori Mizuno

doi:10.1016/j.mbplus.2021.100067

In-depth correlation analysis demonstrates that 4-hydroxyproline at the Yaa position of Gly-Xaa-Yaa repeats dominantly stabilizes collagen triple helix

Matrix Biol Plus. 2021 May 7:10:100067. doi: 10.1016/j.mbplus.2021.100067. eCollection 2021 Jun.

Authors

Yuki Taga¹, Keisuke Tanaka¹, Shunji Hattori¹, Kazunori Mizuno¹

Affiliation

¹ Nippi Research Institute of Biomatrix, 520-11 Kuwabara, Toride, Ibaraki 302-0017, Japan.

Abstract

There is a general consensus that collagen stability is largely maintained by Pro and its major hydroxylated form, 4-hydroxyproline (4Hyp). However, positional difference in their stabilizing effect at the Xaa or Yaa position of collagenous Gly-Xaa-Yaa sequences has remained inconclusive. Here, we position-specifically evaluated the correlation of imino acid contents to denaturation temperature (T_d) of collagen among various vertebrate and invertebrate species, using a recently developed LC-MS methodology. 4Hyp at the Yaa position showed the highest positive correlation with T_d, followed by Pro at the Xaa position, which was even further increased by excluding invertebrates. We confirmed that Gly-Pro-4Hyp liberated after bacterial collagenase digestion was highly positively correlated with T_d. Furthermore, other tripeptides with Yaa position 4Hyp also had comparable positive correlation, excepting negative correlation of Gly-Gly-4Hyp, while tripeptides with Xaa position Pro did not. These data provide evidence that 4Hyp dominantly contributes to thermal stability of collagen depending on its sequence position, especially in vertebrates.

Keywords: APDS, 3-aminopyridyl-N-hydroxysuccinimidyl carbamate; Collagen; Denaturation temperature; Hydroxyproline; Hyp, hydroxyproline; MRM, multiple reaction monitoring; Td, denaturation temperature; Thermal stability.