Radiolocation Devices for Detection and Tracking Small High-Speed Ballistic Objects-Features, Applications, and Methods of Tests.

This article describes radiolocation devices dedicated to the detection and tracking of small high-speed ballistic objects and multifunctional radars. This functionality is implemented by applying space search technology and adaptive algorithms for detection and tracking of air objects in parallel with classic search and tracking of objects in controlled airspace. This article presents examples of the construction of both types of devices produced by foreign companies and Polish industry. The following sections present methods for testing radars with the function of tracking small high-speed ballistic objects along with examples of results of observations of combat ammunition.

Triazole-containing isothiazolidine 1,1-dioxide library synthesis: one-pot, multi-component protocols for small molecular probe discovery.

The construction of two libraries of triazole-containing isothiazolidine 1,1-dioxides is reported utilizing either a one-pot click/aza-Michael or click/OACC esterification protocol. One core dihydroisothiazole 1,1-dioxide scaffold was prepared rapidly on multigram scale via ring-closing metathesis (RCM) and was subjected to a one-pot multicomponent click/aza-Michael protocol with an array of amines and azides for the generation of a 180-member triazole-containing isothiazolidine 1,1-dioxide library. Alternatively, three daughter scaffolds were generated via the aza-Michael of three amino alcohols, followed by a one-pot, multicomponent click/esterification protocol utilizing a ring-opening metathesis polymerization (ROMP)-derived coupling reagent, oligomeric alkyl carbodiimide (OACC) to generate a 41-member library of triazole-containing isothiazole 1,1-dioxides.

S(N)Ar-based, facile synthesis of a library of benzothiaoxazepine-1,1'-dioxides.

The construction of a library of benzothiaoxazepine-1,1'-dioxides utilizing a one-pot, S(N)Ar diversification-ODCT(50) scavenging protocol is reported. This protocol combines microwave irradiation to facilitate the reaction, in conjunction with a soluble ROMP-derived scavenger (ODCT) to afford the desired products in good overall purity. Utilizing this protocol, a 78-member library was successfully synthesized and submitted for biological evaluation.

Strategies for folding of affinity tagged proteins using GroEL and osmolytes.

Obtaining a proper fold of affinity tagged chimera proteins can be difficult. Frequently, the protein of interest aggregates after the chimeric affinity tag is cleaved off, even when the entire chimeric construct is initially soluble. If the attached protein is incorrectly folded, chaperone proteins such as GroEL bind to the misfolded construct and complicate both folding and affinity purification. Since chaperonin/osmolyte mixtures facilitate correct folding from the chaperonin, we explored the possibility that we could use this intrinsic binding reaction to advantage to refold two difficult-to-fold chimeric constructs. In one instance, we were able to recover activity from a properly folded construct after the construct was released from the chaperonin in the presence of osmolytes. As an added advantage, we have also found that this method involving chaperonins can enable researchers to decide (1) if further stabilization of the folded product is required and (2) if the protein construct in question will ever be competent to fold with osmolytes.

GroEL as a molecular scaffold for structural analysis of the anthrax toxin pore.

We analyzed the 440-kDa transmembrane pore formed by the protective antigen (PA) moiety of anthrax toxin in the presence of GroEL by negative-stain electron microscopy. GroEL binds both the heptameric PA prepore and the PA pore. The latter interaction retards aggregation of the pore, prolonging its insertion-competent state. Two populations of unaggregated pores were visible: GroEL-bound pores and unbound pores. This allowed two virtually identical structures to be reconstructed, at 25-A and 28-A resolution, respectively. The structures were mushroom-shaped objects with a 125-A-diameter cap and a 100-A-long stem, consistent with earlier biochemical data. Thus, GroEL provides a platform for obtaining initial glimpses of a membrane protein structure in the absence of lipids or detergents and can function as a scaffold for higher-resolution structural analysis of the PA pore.