Patents and literature

Protein engineering and site-directed mutagenesis is becoming immensely important in both fundamental studies and commercial applications involving proteins and enzymes in biocatalysis. Protein engineering has become a powerful tool to help biochemists and molecular enzymologists elucidate structure-function relationships in enzymic active sites, to understand the intricacies of protein folding and denaturation, and to alter the selectivity of enzymatic catalysis. Commercial applications of engineered enzymes are being developed to increase protein stability, widen or narrow substrate specificity, and to develop novel approaches for use of enzymes in organic synthesis, drug design, and clinical applications. In addition to protein engineering, novel expression systems have been designed to prepare large quantities of genetically engineered proteins. Recent US patents and scientific literature on protein engineering, site-directed mutagenesis, and protein expression systems related to protein engineering are surveyed. Patent abstracts are summarized individually and a list of literature references are given.     

Mass spectrometric approach for the analysis of food proteins

In the study of food proteins, the need for accurate protein structural analysis has been acknowledged because of the fact that nucleotide sequencing alone is of limited analytical value if not combined with relevant information regarding the specific protein expressed and the occurrence of phosphorylation, glycosylation and disulphide bridges, and with the modification induced by the technological treatment. Mass spectrometry, whether used alone or to complement the traditional molecular-based techniques has become fundamental to the structural analysis of proteins. It is, moreover, virtually irreplaceable in determining post-translational modifications as conventional methods cannot deliver reliable data. What lies at the root of this methodological breakthrough is the combination of high-resolution separation techniques such as two-dimensional electrophoresis or capillary reverse- phase high-performance liquid chromatography with mass spectrometric analysis, what is termed "proteomic" analysis. Thus, it appears appropriate to state that the new mass spectrometric techniques have been established as a valuable and efficient tool for protein and peptide analysis in complex mixtures, like those from food matrices, enabling us therefore to provide accurate information on molecular weight and also to put forth a structural assessment at a low-picomole level of material. Thus, a series of alternative approaches have been developed based on advanced mass spectrometric analysis in conjunction with classic protein chemistry in order to provide an in-depth view of food protein structure. This review outlines several of these novel methodologies as they apply to structural characterization of food products.     

Synthesis of functionalized polyhedral oligomeric silsesquioxane (POSS) macromers by microwave assisted 1,3-dipolar cycloaddition

In this paper we report the first synthesis of isoxazolidine and isoxazoline-POSS macromers by 1,3-dipolar cycloaddition reactions of vinyl- and styryl-POSS with N-methyl-C-ethoxycarbonylnitrone and ethoxycarbonyl nitrile oxide, promoted by microwave irradiation. The nature of the resulting cycloadducts has been determined by NOE experiments and supported by computational studies at PM3 and DFT B3LYP/6-31G* levels.     

Transition Metal Complexes with Bidentate Ligands Spanning trans-Positions. VIII. The reactions of the nucleophile trans-[RuCl(NO)(1)] (1 = 2,11-bis(diphenylphosphinomethyl)benzo[c]-phenanthrene) with carbon monoxide and the phosphite ligand (2) (2 = 1-ethyl-3,5,8-trioxa-4-phosphabicyclo (2.2.2)octane)

The preparation of the nucleophile trans-[RuCl(NO)( 1 )], where 1 is the bidentate ligand Ph₂PCH₂C₁₈CH₂PPh₂, and of the five-coordinate species [RuCl(CO)(NO)( 1 )], [RuCl(CO)(NO)(Ph₂PCH₂Ph)₂] and [RuCl(NO)( 2 )( 1 )] are reported. The crystal structure of [RuCl(CO)(NO)( 1 )] shows that the coordination around the metal atom is distorted trigonal bipyramidal with the phosphorus atoms in axial positions. The Ru? N? O bond angle is 142.8°. ¹H- and ³¹P-NMR. and \documentclass{article}\pagestyle{empty}\begin{document}$ \tilde \nu $\end{document}_NO IR.-data for the above complexes are reported and related to the coordination geometry.     

Automorphisms of (B)-geometries

(B)-Geometries are incidence structures arising from permutation sets. The present paper studies the automorphism groups of (B)-Geometries. In certain cases these automorphisms yield examples of inversive planes and of subplanes which are embedded in Minkowski planes (chapter 2). In chapter 3 we describe the automorphism groups of the (B)-Geometries arising from the groups PL(2, pⁿ) and AL(1, pⁿ) in their natural representations on the points of the projective and affine line.Dedicated to Prof.Dr. Walter Benz on his 60th birthdayWork done within the activity of G.N.S.A.G.A. of C.N.R. and supported by the 40% grants of M.U.R.S.T.     

GO-SWCNT Buckypapers as an Enhanced Technology for Water Decontamination from Lead

Water decontamination is an important challenge resulting from the incorrect disposal of heavy metal waste into the environment. Among the different available techniques (e.g., filtration, coagulation, precipitation, and ion-exchange), adsorption is considered the cheapest and most effective procedure for the removal of water pollutants. In the last years, several materials have been tested for the removal of heavy metals from water, including metal-organic frameworks (MOFs), single-walled carbon nanotubes (SWCNTs), and graphene oxide (GO). Nevertheless, their powder consistency, which makes the recovery and reuse after adsorption difficult, is the main drawback for these materials. More recently, SWCNT buckypapers (SWCNT BPs) have been proposed as self-standing porous membranes for filtration and adsorption processes. In this paper, the adsorption capacity and selectivity of Pb²⁺ (both from neat solutions and in the presence of other interferents) by SWCNT BPs were evaluated as a function of the increasing amount of GO used in their preparation (GO-SWCNT buckypapers). The highest adsorption capacity, 479 ± 25 mg g⁻¹, achieved for GO-SWCNT buckypapers with 75 wt.% of graphene oxide confirmed the effective application of such materials for cheap and fast water decontamination from lead.     

Temperature dependence of the time-resolved emissions of CsI:Tl

Abstract

Time-resolved emissions of Csl:T1 are investigated. The system is laser-excited in the A-band at 308 nm and the emissions are observed in the range 370–650 nm, from 30 K to 300 K. Their analysis by means of a deconvolution permits the valuation of decay-times down to 1 ns. At every temperature many bands are observed and some of them show slow and fast components. The decay-times of the fast components are in the range 1–10 ns while the slow ones are even longer than 1 μs. In many cases intermediate decay-times of the order of 100 ns exist. The competition among the bands interests the application of this system as active material for tunable solid-state laser.