Structural basis of DegP-protease temperature-dependent activation

Abstract

Protein quality control is an essential cellular function and it is mainly executed by a large array of proteases and molecular chaperones. One of the bacterial HtrA protein family members, the homo-oligomeric DegP-protease, plays a crucial role in the Escherichia coli (E. coli) protein quality control machinery by removing unfolded proteins or preventing them from aggregation and chaperoning them until they are properly folded within the periplasm. DegP contains two regulatory PDZ domains, which play key roles in substrate recognition as well as in the transformation of DegP to proteolytic cage-like structures. Here, we analyse the interaction and dynamics of the PDZ-domains of DegP underlying this transformation in solution by high-resolution NMR spectroscopy. We identify an interdomain molecular lock guiding the interactions between both PDZ domains, regulated by fine-tuned protein dynamics and potentially conserved in proteins harboring tandem PDZ domains.

An ancient enzyme finds a new home: Prevalence and neofunctionalization of trypsin in marine phytoplankton

“…The HtrA/ Deg were initially identified and named according to function in Escherichia coli mutants, which exhibited growth repression at elevated temperatures and failed to digest misfolded protein in the periplasm, respectively (Lipinska et al 1988, Strauch andBeckwith 1988). The phytoplankton trypsin II genes reported in the present study feature a trypsin_2 domain and 1-2 PDZ domains and share the same structure architecture of HtrA/Deg previously reported (Clausen et al 2011, Sulskis et al 2021, which were considered homologs of plant DegP/ HtrA. Hence, the large amount of phytoplankton trypsin gene duplication with trypsin I and trypsin II differentiation and specific characteristics documented in the present study suggests that they may have evolved different important functions.…”

“…2011, Sulskis et al. 2021), which were considered homologs of plant DegP/HtrA. Hence, the large amount of phytoplankton trypsin gene duplication with trypsin I and trypsin II differentiation and specific characteristics documented in the present study suggests that they may have evolved different important functions.…”

Stress-Responsive Periplasmic Chaperones in Bacteria

“…Temperature undoubtedly affects the folding state of proteins; thus these results partially explain the role of temperature in functional transition of DegP. In recent study, the analysis of the interaction and dynamics of the PDZ-domains of DegP by high-resolution NMR spectroscopy reveals that PDZ1-PDZ2 interaction through Met-280 and Tyr-444 residues is crucial for the temperature-dependent regulation in the oligomeric states of DegP ( Šulskis et al, 2020 ).…”

Disulfide-bond-induced structural frustration and dynamic disorder in a peroxiredoxin from MAS NMR

“…This approach yielded the following degree of assignment (∼ 92%): Ile δ1 (13/13), Leu δ1, δ2 (30/34), and Val γ1, γ2 (34/36). Translational diffusion coefficients were measured by recording a series of 1D 13 C -edited DOSY spectra at different tem-peratures ranging from 25 • C to 60 • C, using a pulse scheme ( 13 C -edited BPP-LED (70)) that is similar to an 15 N-edited BPP-LED experiment with 15 N and 13 C pulses interchanged (71). The gradient duration δ was adapted to 3.2 ms instead of 4.8 ms used in the 15 N-filtered version and a diffusion delay T of 400 ms and a τ of 0.1 ms were used.…”