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Many pathogenic gram-negative bacteria including Salmonella typhi utilize type III secretion systems (T3SSs) to inject bacterial proteins into host cells and to initiate infections. One of the essential components of the T3SS is the tip protein known as SipD, translocon component via the type III secretion system SPI-1. Here, recombinant SipD is produced and crystallized; the details of cloning, expression, and crystallization are reported. Crystals of SipD are obtained by sitting-drop vapour diffusion method. X-ray diffraction data are collected up to 3.8 A resolution. Single crystals belong to the monoclinic sp. gr. P2; unit-cell parameters: a = 70.86, b = 103.70, c = 89.28 A, β = 107.63°.

IN BRIEF Given the progressive nature of type 2 diabetes, treatment intensification is usually necessary to maintain glycemic control. However, for a variety of reasons, treatment is often not intensified in a timely manner. The combined use of basal insulin and a glucagon-like peptide-1 receptor agonist is recognized to provide a complementary approach to the treatment of type 2 diabetes. This review evaluates the efficacy and safety of two co-formulation products, insulin degludec/liraglutide and insulin glargine/lixisenatide, for the treatment of type 2 diabetes inadequately controlled on either component agent alone. We consider the benefits and limitations of these medications based on data from randomized clinical trials and discuss how they may address barriers to treatment intensification.

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), one of the scavenger receptors for oxidized low-density lipoprotein cholesterol (ox-LDL), plays a crucial role in the uptake of ox-LDL by cells in the arterial wall. Mounting evidence suggests a role for LOX-1 in various steps of the atherosclerotic process, from initiation to plaque destabilization. Studies of the genetic structure of LOX-1 have also uncovered various genetic polymorphisms that could modulate the risk of atherosclerotic cardiovascular events. As evidence supporting the vital role of LOX-1 in atherogenesis keeps accumulating, there is growing interest in LOX-1 as a potential therapeutic target. This review discusses the discovery and genetics of LOX-1; describes existing evidence supporting the role of LOX-1 in atherogenesis and its major complication, myocardial ischemia; and summarizes LOX-1 modulation by some naturally occurring compounds and efforts toward development of small molecules and biologics that could be of therapeutic use.

This paper presents a number of novel methods to measure the junction temperature and to estimate the health of gallium nitride light-emitting diodes (LEDs). The methods are based on measurements of the dynamic impedance and optical output. Our experimental analysis reveals temperature sensitive parameters of the electrical and optical responses. Moreover, a correlation between the non-radiative current characterizing the active region defects and the small-signal impedance is shown. The demonstrated methods can be applied to enhance existing temperature-monitoring techniques. The derived dependencies also build a foundation for advanced in-field health monitoring of the LEDs using the infrastructure of visible light communication systems. Such methods and techniques are valuable for predictive maintenance of solid state lighting systems.

The lytic enzyme, endolysin, is encoded by bacteriophages (phages) to destroy the peptidoglycan layer of host bacterial cells. The release of phage progenies to start the new infection cycle is dependent on the cell lysis event. Endolysin encoded by DLP12 cryptic prophage is a SAR endolysin which is retained by the bacterium presumably due to the benefit it confers. The structure of DLP12 endolysin (Id: 4ZPU) determined at 2.4 A resolution is presented here. The DLP12 endolysin structure shows a modular nature and is organized into distinct structural regions. One of the monomers has the loops at the active site in a different conformation. This has led to a suggestion of depicting possibly active and inactive state of DLP12 endolysin. Comparison of DLP12 endolysin structure and sequence with those of related endolysins shows the core three-dimensional fold is similar and the catalytic triad geometry is highly conserved despite the sequence differences. Features essential for T4 lysozyme structure and function such as the distance between catalytic groups, salt bridge and presence of nucleophilic water are conserved in DLP12 endolysin and other endolysins analyzed.

The P1 lysozyme Lyz is secreted to the periplasm of Escherichia coli and accumulates in an inactive membrane-tethered form. Genetic and biochemical experiments show that, when released from the bilayer, Lyz is activated by an intramolecular thiol-disulfide isomerization, which requires a cysteine in its N-terminal SAR (signal-arrest-release) domain. Crystal structures confirm the alternative disulfide linkages in the two forms of Lyz and reveal dramatic conformational differences in the catalytic domain. Thus, the exported P1 endolysin is kept inactive by three levels of control—topological, conformational, and covalent—until its release from the membrane is triggered by the P1 holin.