Dataset Information

The N terminus of the serpin, tengpin, functions to trap the metastable native state.

ABSTRACT: Serpins fold to a metastable native state and are susceptible to undergoing spontaneous conformational change to more stable conformers, such as the latent form. We investigated conformational change in tengpin, an unusual prokaryotic serpin from the extremophile Thermoanaerobacter tengcongensis. In addition to the serpin domain, tengpin contains a functionally uncharacterized 56-amino-acid amino-terminal region. Deletion of this domain creates a variant--tengpinDelta51--which folds past the native state and readily adopts the latent conformation. Analysis of crystal structures together with mutagenesis studies show that the N terminus of tengpin protects a hydrophobic patch in the serpin domain and functions to trap tengpin in its native metastable state. A 13-amino-acid peptide derived from the N terminus is able to mimick the role of the N terminus in stabilizing the native state of tengpinDelta51. Therefore, the function of the N terminus in tengpin resembles protein cofactors that prevent mammalian serpins from spontaneously adopting the latent conformation.

SUBMITTER: Zhang Q

PROVIDER: S-EPMC1905895 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The N terminus of the serpin, tengpin, functions to trap the metastable native state.

Zhang Qingwei Q Buckle Ashley M AM Law Ruby H P RH Pearce Mary C MC Cabrita Lisa D LD Lloyd Gordon J GJ Irving James A JA Smith A Ian AI Ruzyla Katya K Rossjohn Jamie J Bottomley Stephen P SP Whisstock James C JC

EMBO reports 20070608 7

Serpins fold to a metastable native state and are susceptible to undergoing spontaneous conformational change to more stable conformers, such as the latent form. We investigated conformational change in tengpin, an unusual prokaryotic serpin from the extremophile Thermoanaerobacter tengcongensis. In addition to the serpin domain, tengpin contains a functionally uncharacterized 56-amino-acid amino-terminal region. Deletion of this domain creates a variant--tengpinDelta51--which folds past the nat ...[more]

PMID: 17557112

Similar Datasets

Project description:Protein glycosylation commonly stabilizes proteins thereby increasing protein half-lives and protecting against denaturation or proteolytic degradation. While generally beneficial, such stabilization is potentially disadvantageous in the case of inhibitory serpins. These protease inhibitors are metastable and a conformational transition to a more stable form is key to their function. Instability is therefore essential for these inhibitory serpins and mutagenesis has demonstrated that substantial stabilization results in compromised function. We have used optical spectroscopy and hydrogen/deuterium exchange and mass spectrometry to investigate the effects of glycosylation on the human serpin alpha-1 antitrypsin (?(1)-AT). Previous studies found that unglycosylated recombinant ?(1)-AT populates a molten globule at low denaturant and that the ability to populate this state is correlated with efficient protease inhibition. Further, a high degree of conformational flexibility was found in several important regions. Guanidine hydrochloride denaturation monitored by circular dichroism indicates that plasma ?(1)-AT, which is glycosylated at 3 sites, is substantially stabilized relative to the unglycosylated form. However, hydrogen exchange reveals complete loss of protection in plasma ?(1)-AT above 1 M GuHCl, similar to what is seen for the recombinant form. Sugars therefore appear to stabilize the compact denatured state of ?(1)-AT without significant stabilization of the folded state. Native state hydrogen exchange reveals minor perturbations to native flexibility, but high flexibility in key regions such as the f helix is conserved. ?-strand 1c is stabilized in plasma ?(1)-AT, which may confer increased resistance to forming pathogenic polymers. Overall, our results indicate that glycosylation of inhibitory serpins does not interfere with either native state flexibility or the native instability that is required for efficient function, though it may confer resistance to degradation by proteases and thus extend the half-life of circulating serpins.

Dataset Information

The N terminus of the serpin, tengpin, functions to trap the metastable native state.

Publications

The N terminus of the serpin, tengpin, functions to trap the metastable native state.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure