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Genetic engineering, which was started by the E. coli gene manipulation, has led to rapid development in all area of life sciences. Recently, genetic engineering, which is an insertion or a removal technique of a specific gene on chromosomes, has been established and is usefully available in the applied life sciences including medicine and agriculture. In this review, we briefly explain pest management focusing on Release of Insects carrying a Dominant Lethal (RIDL) that is a highly economic and environment- friendly method of biological pest control. Although at present RIDL confronts many difficulties in applying directly in fields, it will be one of the best methods for the pest management in the near future without pesticides and disturbing ecosystem by the continued development of genetic engineering. However, these powerful techniques must be considered with great care to avoid harm to ecosystem.

The fluorescence of 4',6-diamidino-2-phenylindole (DAPI) bound to DNA at a [DAPI]/[DNA base] ratio of 0.005 was quenched by meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (TMPyP) or cis-bis(N-methylpyridinium-4-yl)porphyrin (BMPyP) when both DAPI and either porphyrin spontaneously bound to the same DNA strand. The quenching was investigated using the “one-dimensional inner sphere” and the “Forster resonance energy transfer” (FRET) models. Total quenching occurred when DAPI and TMPyP were up to 19.3 base pairs or 66 A apart. BMPyP could quench the fluorescence up to 13.9 base pairs or 47 A. TMPyP, which intercalated between the DNA base-pairs, appeared to be a better acceptor than BMPyP, which stacked along the DNA stem. The higher quenching and higher resonance energy transfer efficiency of TMPyP was due to the larger overlap integral between its absorption spectrum and the emission spectrum of DNA-bound DAPI.

Crystal structure determinations on Cu(II) and Zn(II) complexes of tridentate and quadridentate azetidine derivatives show the ligands to be facultative for square-pyramidal and trigonal bipyramidal coordination geometries. While various contributions to the chirality of the complexes are possible, single diastereoisomeric forms (as enantiomer mixtures) have been isolated in all cases in the solid state. Analysis of lattice interactions indicates that H-bonding and aromatic stacking interactions are generally important.

Ag 4 Br 4 nanoclusters have been synthesized in about 75% of the sodalite cavities of fully K + -exchanged zeolite A (LTA). An additional KBr molecule is retained in each large cavity as part of a near square-planar K 4 Br 3 + cation. A single crystal of Ag 1 2 -A, prepared by the dynamic ion-exchange of Na 1 2 -A with aqueous 0.05 M AgNO 3 and washed with CH 3 OH, was placed in a stream of flowing 0.05 M KBr in CH 3 OH for two days. The crystal structure of the product (K9(K4Br)Si 1 2 Al 1 2 O 4 8 .0.75Ag 4 Br 4 , a = 12.186(1) A) was determined at 294 K by single-crystal X-ray diffraction in the space group Pm3 m. It was refined with all measured reflections to the final error index R 1 = 0.080 for the 99 reflections for which F o > 4σ(F o ). The thirteen K + ions per unit cell are found at three crystallographically distinct positions: eight K + ions in the large cavity fill the six-ring site, three K' ions fill the eight-rings, and two K' ions are opposite four-rings in the large cavity. One bromide ion per unit cell lies opposite a four-ring in the large cavity, held there by two eight-ring and two six-ring K + ions (K 4 Br 3 + ). Three Ag' and three Br ions per unit cell are found on 3-fold axes in the sodalite unit, indicating the formation of nano-sized Ag 4 Br 4 clusters (interpenetrating tetrahedra; symmetry T d ; diameter ca. 7.9 A) in 75% of the sodalite units. Each cluster (Ag-Br = 2.93(3) A) is held in place by the coordination of its four Ag + ions to the zeolite framework (each Ag' cation is 2.52(3) A from three six-ring oxygens) and by the coordination of its four Br ions to K' ions through six-rings (Br-K = 3.00(4) A).

Characterisation, largely through crystal structure determinations of their metal complexes, of the polyamine products of several reactions between (in all but one case) polyalcohol benzenesulfonates and 1,2- and 1,3-diamines, confirmed that intramolecular reaction pathways are important only in the 1,2-diamine reactions. Even under conditions where the amine reactants are in large excess, however, it is possible to obtain products resulting from alkylation of a diamine by more than one molecule of sulfonate (or, in one case, of a bromochloroalkane). In metal ion complexes formed by the new ligands there are examples of only partial coordination of the N-donor sites, giving species which might be suitable for further, selective functionalisation at the unbound centres. Conversion of the complexes into macrocyclic derivatives also suited to further functionalisation is straightforward.

The positions of Xe atoms encapsulated in the cavities of fully dehydrated zeolite A of unit-cell composition Cs3Na8HSi12Al12O48 (Cs3-A) have been determined. Cs3-A was exposed to 255 atm of xenon at 400 °C for 7 days, followed by cooling at pressure to encapsulate Xe atoms; a second crystal was treated similarly at 450 atm, and a third at 1020 atm. The resulting crystal structures of Cs3-A(2.5Xe) (crystal 1, a = 12.245(2) A, R1 = 0.056, R2 = 0.059), Cs3-A(4.5Xe) (crystal 2, a = 12.258(2) A, R1 = 0.061, R2 = 0.058), and Cs3-A(5.25Xe) (crystal 3, a = 12.236(2) A, R1 = 0.061, R2 = 0.057) were determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1) °C and 1 atm. The approximately 2.5, 4.5, and 5.25 Xe atoms per unit cell, respectively, are distributed over three crystallographically distinct positions. At the center of each sodalite unit in crystals 1, 2, and 3, respectively, are 0.5, 0.75, and 0.75 Xe atoms at Xe(1); in addition, off center in crystal 3 are 0.25 Xe a...

Two new polyamine ligands, L1 and L2, incorporating pyridyl and aliphatic amine donor sites have been prepared and their reaction with copper(ii) yields the mono- and binuclear complexes [Cu(L1)](ClO4)2 (1) and [Cl2Cu(L2)CuCl(H2O)]ClO4 (2), respectively. The X-ray structure of 1 confirms that the five nitrogen donors of L1 are bound to the central copper ion to give a distorted square pyramidal coordination sphere. In 2, L2 acts as a bridging ligand with its N3-donor coordination domains separated by a m-xylylene spacer group. An unusual feature of this latter complex is that symmetrical L2 gives rise to non-equivalent coordination behaviour at the individual copper sites; while both sites display five-coordination with distorted square pyramidal arrangements, they differ in having N3Cl2- and N3ClO-donor atom sets, respectively. The electron paramagnetic resonance (EPR) spectra of both complexes are discussed. Variable temperature magnetic susceptibility data confirmed the absence of magnetic interactions in 1 while a weak antiferromagnetic interaction between copper(ii) centres occurs in 2.