This paper presents the methodology of an applied geophysical and remote sensing research at river deltas for their subsurface and surface structure and its application in the deltaic plain of Pineios River (Thessaly, Greece). The scope is to primarily calculate the thickness of deltaic post alpine deposits, with the contribution of Transient Electromagnetic Method (TEM), but also identify the surficial characteristics (biotic/ abiotic) of the area with the appropriate combination of spectral bands and spectral indices. Regarding the remote sensing approach, some geomorphological features were outlined.
View Article and Find Full Text PDFYiiP is a dimeric antiporter from the cation diffusion facilitator family that uses the proton motive force to transport Zn across bacterial membranes. Previous work defined the atomic structure of an outward-facing conformation, the location of several Zn binding sites, and hydrophobic residues that appear to control access to the transport sites from the cytoplasm. A low-resolution cryo-EM structure revealed changes within the membrane domain that were associated with the alternating access mechanism for transport.
View Article and Find Full Text PDFThe bacterial protease ClpP consists of 14 subunits that assemble into two stacked heptameric rings. The central degradation chamber can be accessed via axial pores. In free ClpP, these pores are obstructed by the N-terminal regions of the seven subunits at either end of the barrel.
View Article and Find Full Text PDFAcyldepsipeptides (ADEPs) antibiotics bind to Escherichia coli ClpP mimicking the interactions that the IGL/F loops in ClpA or ClpX ATPases establish with the hydrophobic pockets surrounding the axial pore of the tetradecamer that the protease forms. ADEP binding induces opening of the gates blocking the axial channel of ClpP and allowing protein substrates to be translocated and hydrolysed in the degradation chamber. To identify the structural determinants stabilizing the open conformation of the axial channel for efficient substrate translocation, we constructed ClpP variants with amino acid substitutions in the N-terminal region that forms the axial gates.
View Article and Find Full Text PDFProteolysis is an important process for many aspects of bacterial physiology. Clp proteases carry out a large proportion of protein degradation in bacteria. These enzymes assemble in complexes that combine the protease ClpP and the unfoldase, ClpA or ClpX.
View Article and Find Full Text PDFObjectives: The aim of this study was to evaluate the results of interlocking intramedullary nailing in the treatment of extra-articular distal tibial fractures and nonunions.
Methods: The study included 45 patients (mean age 42 years; range 27 to 52 years) who were treated with interlocking intramedullary nailing for distal tibial fractures (n=35) and nonunions (n=10). Of 35 fractures, 31 were closed and four were open.