Structure of Cu2(indomethacin)4 and the reaction with superoxide in aprotic systems

The copper complex of indomethacin (1-(p-chlorobenzoyl)-5-methoxy-2-methyl-indole acetate), a common anti-inflammatory drug, was prepared and characterized. Crystal structure determination revealed the dimeric form of the 1:2 complex, namely Cu₂(indomethacin)₄ · L₂, in the unit cell. Suprisingly, the copper-copper distance (263 pm) was very close to metallic copper (256 pm). The two coordination sites in the copper-copper axis can be readily replaced by superoxide. An intriguing similarity to Cu₂(acetate)₄ was seen.Due to the lipophilic nature of the indomethacin ligand, this copper complex reacted with superoxide in aprotic solvents. The superoxide dismutating activity was successfully demonstrated in Me₂SO/water and acetonitrile/water mixtures using the nitro-blue tetrazolium assay and pulse radiolysis. The second-order rate constant of 6 · 10⁹ M^?1 · s^?1 in strictly aqueous systems dropped only slightly to 1.1 · 10⁹ M^?1 · s^?1 when aprotic solvents were used. This is the fastest rate constant ever observed for a copper-dependent dismutation of superoxide. The KO₂-induced lipid peroxidation in both erythrocytes and liver microsomes was suppressed by 70% in the presence of 1 · 10^?10 mol · ml^?1 of Cu₂(indomethacin)₄. The inhibitory action dropped to 25% when Cu₂Zn₂superoxide dismutase was employed. The formation of copper · indomethacin in rat serum after administration of indomethacin was shown in vitro and in vivo.     

Beta-glucoside (bgl) operon of Escherichia coli K-12: nucleotide sequence, genetic organization, and possible evolutionary relationship to regulatory components of two Bacillus subtilis genes.

Wild-type Escherichia coli cells are unable to grow on beta-glucosides. Spontaneous mutants arise, however, which are able to utilize certain aromatic beta-glucosides such as salicin or arbutin as carbon sources, revealing the presence of a cryptic operon called bgl. Mutations activating the operon map within (or close to) the promoter region of the operon and are due to the transposition of an IS1 or IS5 insertion element into this region. This operon was reported to consist of three genes coding for a phospho-beta-glucosidase, a specific transport protein (enzyme IIBgl), and a positively regulating protein. We have defined the extent and location of three structural genes, bglC, bglS, and bglB, and have determined their DNA sequence. The amino acid sequences deduced from the open reading frames together with deletion and subcloning analyses suggest that the first gene, bglC, codes for the regulatory protein, the second, bglS, codes for the transport protein, and the third, bglB, for phospho-beta-glucosidase. A fourth gene may exist which codes for a product of unknown function. We discuss structural features of the DNA sequence which may bear on the regulation of the operon. Homologies to sequences preceding the gene for an excreted levansucrase of Bacillus subtilis, which are known to be involved in the regulation of this gene, and to sequences preceding the gene for an excreted beta-endoglucanase of B. subtilis, for which data pertaining to regulation are not yet available, suggest a close evolutionary relationship among the regulatory components of all three systems.     

Changes in the auditory system of locusts (Locusta migratoria and Schistocerca gregaria) after deafferentation

Deafferentation experiments during postembryonic development show morphological and/or physiological changes of receptor fibers and of identified auditory interneurons in the CNS of the locusts Locusta migratoria and Schistocerca gregaria after unilateral ablation of one tympanic organ either in the larva or the adult animal.

Assignment of the gene encoding the catalytic subunit Cβ of CAMP-dependent protein kinase to the p36 band on chromosome

Summary A cDNA for the human catalytic subunit (C) of cAMP-dependent protein kinase (PKA) has been cloned from a testis cDNA library. In the present study, we have determined the chromosomal localization of this gene using a cDNA for C as a probe. Southern blot analysis of genomic DNA from human/mouse cell hybrids revealed that the presence or absence of a 20-kbXbaI fragment, which hybridized with the C probe, was concordant with the presence of human chromosome 1.In situ hybridization to metaphase chromosome confirmed the somatic cell hybrid data and regionally mapped the C gene of PKA to the p36 band on chromosome 1.     

Isolation and regional localization of a large collection (2,000) of single-copy DNA fragments on human chromosome 3 for mapping and cloning tumor suppressor genes

Summary A collection of 2,000 lambda phage-carrying human single-copy inserts (> 700 bp) were isolated from two chromosome-3 flow-sorted libraries. The single-copy DNA fragments were first sorted into 3p and 3q locations and about 700 3p fragments were regionally mapped using a deletion mapping panel comprised of two humanhamster and two-human-mouse cell hybrids, each containing a chromosome 3 with different deletions in the short arm. The hybrids were extensively mapped with a set of standard 3p markers physically localized or ordered by linkage. The deletion mapping panel divided the short arm into five distinct subregions (A-E). The 3p fragments were distributed on 3p regions as follows: region A, 26%; B, 31%; C, 4%; D, 4% and E, 35%. We screened 300 single-copy DNA fragments from the distal part of 3p (regions A and B) with ten restriction endonucleases for their ability to detect restriction fragment length polymorphisms (RFLPs). Of these fragments 110 (36%) were found to detect useful RFLPs: 35% detected polymorphisms with frequency of heterozygosity of 40% or higher, and 25% with frequency of 30% or higher. All polymorphisms originated from single loci and most of them were of the base pair substitution type. These RFLP markers make it possible to construct a fine linkage map that will span the distal part of chromosome 3p and encompasses the von Hippel-Lindau disease locus. The large number of single-copy fragments (2,000) spaced every 100–150 kb on chromosome 3 will make a significant contribution to mapping and sequencing the entire chromosome 3. The 300 conserved chromosome 3 probes will increase the existing knowledge of man-mouse homologies.     

Functional morphology of the asterionic region in extant hominoids and fossil hominids

Asterionic sutural patterns in Plio-Pleistocene hominid crania have never been examined in detail. We present an analysis of this anatomical region in Australopithecus and Homo and relate different sutural patterns to functional changes in the masticatory apparatus. The great apes and A. afarensis share the common adult higher primate sutural pattern referred to as the "asterionic notch," which develops in response to the hypertrophy of posterior temporalis muscle fibers and the consequent formation of compound temporal/nuchal crests. This sutural configuration also appears to be present on the early Homo cranium KNM-ER 1805. In contrast, adult male A. boisei crania exhibit a unique pattern where the temporal squama overlaps the parietal which, in turn, overlaps the par mastoidea and the upper scale of the occipital bone. We relate this arrangement to the need to reinforce the rear of a thin-walled braincase against the net tensile forces exerted by the temporalis and nuchal muscles. The common juvenile hominoid edge-to-edge asterionic articulation is maintained in adult A. africanus, A. robustus, female A. boisei, and most Homo crania. We discuss the latter pattern in regard to anterior temporalis hypertrophy in A. africanus, A. robustus, and A. boisei and to craniofacial paedomorphosis in Homo.     

Seasonal variation in catabolic enzyme activities in breast muscle of some migratory birds

Summary Five bird species were examined in order to ascertain if any changes in flight muscle catabolism take place between breeding season and migration. Two different patterns were discovered. The first consists of a high oxidative capacity and a low glycolytic and anaerobic capacity during migration. The converse occurs during the breeding season, i.e. low oxidative, high glycolytic and anaerobic capacity. The pattern was found in those species that deposit large amounts of fat prior to migration. The second pattern was similar to the first, but there was no change in fatty acid oxidation capacity between breeding season and migration. The pattern was found in those species that do not deposit much fat towards migration. These changes are believed to reflect differences in migration strategy and differences in locomotory activity during different seasons. Deviations from these patterns are discussed.     

Isolation and characterization of a new thermophilic and autotrophic methane producing bacterium:Methanobacterium thermoaggregans spec. nov.

Methanobacterium thermoaggregans is a new thermophilic autotrophic rod-shaped methane producing bacterium. The organism likes to form aggregates during growth and utilizes only H₂ and CO₂ as substrates. Growth optimum is at 65°C with a doubling time of 3.5 h. Optimal growth occurs at pH-values between 7 and 7.5. The addition of yeast extract to the mineral salt medium stimulates growth. The DNA base composition is 42 mol% G+C. The organism was isolated from mud taken from a cattle pasture. Because of its optimal growth temperature and its tendency to form aggregates the nameMethanobacterium thermoaggregans is suggested.Abbreviations G+C Guanine+cytosine     

On-line monitoring of enzymes in downstream processing by flow injection analysis (FIA)

Flow injection analysis (FIA) has been employed to automate enzyme assays for formate dehydrogenase (FDH) and l-leucine dehydrogenase (l-LeuDH). Coupled to a special sampling device the FIA assays were used to monitor on-line downstream processes, e.g. disintegration of microbial cells and cross-flow filtration of cell homogenates.