Descripción: The crystal structure of the dimeric title compound, C19H 22O5H, is dominated by a head-to-head hydrogen-bonding inter-action between centrosymmetrically related carboxyl groups in each monomer. The result is a dimeric axis of unusual length (ca 34 Å), but still shorter than what could be expected for a fully extended chain, owing to two turning points in the oligo-eth-oxy ends. This allows for an explanation of the structure of the smectic mesophase exhibited by this compound and at the same time fully validates former geometric estimations based on PM3 calculations. © 2009 International Union of Crystallography.

Descripción: A new polymeric phase of zinc(II) oxydiacetate, catena-poly[[[diaquazinc(II)]-μ-oxydiacetato] hydrate], {[Zn(C4H4-O5)(H2O)2] ·H2O}n, isomorphous with the Co homologue [Hatfield, Helms, Rohrs, Singh, Wasson & Weller (1987). Proc. Indian Acad. Sci. Chem. Sci. 98, 23-31], is reported. It presents a chain-like structure, generated by ZnO6 cores which are bridged by carboxylate groups in an anti-anti conformation along the unique crystallographic b axis. The chains are held together through hydrogen-bonding interactions with the three water molecules.

Descripción: The role of short-chain fatty acids in the host-seeking behaviour of Triatoma infestans larvae was investigated using a locomotion compensator. Several short-chain fatty acids were tested alone over a wide range of doses, or in combination with L-lactic acid (L-LA; 100 μg). Bugs showed no attractive response to single carboxylic acids, but when L-LA was added to airstreams carrying specific intensities of either propionic (C3; 100 μg), butyric (C4; 1 μg) or valeric acid (C5; 1 μg), these mixtures elicited an attractive response, evincing a synergistic effect. No orientation response was observed when caproic acid (C6) was offered with L-LA at the doses tested. Two blends were created: (1) C3, C4 and C5 combined at the effective doses when added with L-LA [C3C4C5 (1)], and (2) C3, C4 and C5 combined at a third of those intensities [C3C4C5 (2)]. Both blends were tested alone, with L-LA (100 μg), with a sub-threshold concentration of CO2 (300 p.p.m. above the ambient level), and combined with both compounds together. Oriented responses of bugs were only observed with the blend (2) added with L-LA and with the combination of this lure with CO2. This last combination evoked a behavioural response similar in intensity to that induced by a live mouse. © Oxford University Press 2004; all rights reserved.

Descripción: Bioreactor cultures of Escherichia coli recombinants carrying phaBAC and phaP of Azotobacter sp. FA8 grown on glycerol under low-agitation conditions accumulated more poly(3-hydroxybutyrate) (PHB) and ethanol than at high agitation, while in glucose cultures, low agitation led to a decrease in PHB formation. Cells produced smaller amounts of acids from glycerol than from glucose. Glycerol batch cultures stirred at 125 rpm accumulated, in 24 h, 30.1% (wt/wt) PHB with a relative molecular mass of 1.9 MDa, close to that of PHB obtained using glucose. Copyright © 2010, American Society for Microbiology. All Rights Reserved.

Descripción: 1. 1. The sensitivity of partially purified low Km, phosphodiesterase (PDE) from Mucor rouxii to pharmacological agents and cAMP analogs was studied. The IC50 obtained were compared with those reported for PDEs from higher eukaryotes. 2. 2. The best inhibitors of the hydrolysis of 1 gmM cAMP were SQ 65.442 (IC50, c 10 μM), dipyridamol and CI 930. cGMP was not an inhibitor (IC50 > 1000 μm). 3. 3. The cAMP analogs were tested as inhibitors of the hydrolysis of 0. l μM cAMP. 8-Aminohexylamino cAMP was the best inhibitor with an IC50 of c 1 μM. 4. 4. A sedimentation profile of Mucor PDE was assayed in the presence of several pharmacological inhibitors and eAMP analogs. No isoforms with different sensitivity towards the inhibitors were detected. Forms with slightly different behaviour towards some cAMP analogs were observed. © 1990.

Descripción: The title compound, tetrakis(μ-3,4,5-triethoxybenzoato κ 2 O:O′)bis[(pyrazine-κN)rhodium(II)](Rh-Rh). [Rh 2 (C 13 -H 17 O 5 ) 4 (C 4 H 4 N 2 ) 2 ], crystallizes on an inversion centre in the triclinic space group P1̄. The equatorial carboxylate ligands bridge the two Rh 11 atoms, giving a binuclear lantern-like structure. The pyrazine molecules occupy the two axial coordination sites. The phenyl rings are titled by ca 10° with respect to the attached carboxylate groups. The pyrazine planes have a torsion angle of ca 19° around the Rh-N bond with respect to the plane of the nearer carboxylate group and are not coplanar with the Rh-Rh bond.