Effect of biocatalyst activity changes in continuous reactions in the gas phase

Summary In the gas phase bioreactions, continuous production rate depends on the biocatalyst activity and complete dehydration causes the biocatalyst to lose most of its activity. To overcome these difficulties, a theoretical method is suggested along with the new design of biocatalyst. This will be applicable and helpful for the optimization of the gas phase continuous bioreaction.Nomenclature C_A ethanol concentration [mol/mL] - C_P acetaldehyde concentration [mol/mL] - X_P acetaldehyde composition     

Voltage-Gated Potassium Channel Genes Are Clustered in Paralogous Regions of the Mouse Genome

Cloning of the Drosophila Shaker gene established that a neurological phenotype including locomotor dysfunction can be caused by a mutation in a voltage-gated potassium (K) channel gene. Shaker sequences have been used to isolate a large family of related K channel genes from both flies and mammals. Toward elucidating the evolutionary relationship between loci and the potential causal connection that K channels may have to mammalian genetic disorders, we report here the genetic mapping of 12-16 different murine, voltage-gated K channel genes. We find that multiple genes, in some cases from distantly related K channel subfamilies, occur in clusters in the mouse genome. These mapping results suggest that the K channel gene subfamilies arose through ancient localized gene duplication events, followed by chromosomal duplications and rearrangements as well as further gene duplication. We also note that several neurologic disorders of both mouse and human are associated with the chromosomal regions containing K channel genes.     

Pathogenesis of SIVmac251 after atraumatic inoculation of the rectal mucosa in rhesus monkeys

Intrarectal inoculation of rhesus monkeys with low doses of SIV_mac led to a prolonged clinical and virological latency that was not observed for high intrarectal doses or for intravenous inoculation. Animals infected intrarectally with low virus doses remained negative for serum antibody responses to SIV for at least one year even though they readily transferred SIV to naive recipients via transfusion of whole blood.     

Molecular Characterization and Mapping of Murine Genes Encoding Three Members of the Stefin Family of Cysteine Proteinase Inhibitors

Stefins or Type 1 cystatins belong to a large, evolutionarily conserved protein superfamily, the members of which inhibit the papain-like cysteine proteinases. We report here on the molecular cloning and chromosomal localization of three newly identified members of the murine stefin gene family. These genes, designated herein as mouse stefins 1, 2, and 3, were isolated on the basis of their relatively increased expression in moth-eaten viable compared to normal congenic mouse bone marrow cells. The open reading frames of the stefin cDNAs encode proteins of approximately 11.5 kDa that show between 50 and 92% identity to sequences of stefins isolated from various other species. Data from Southern analysis suggest that the murine stefin gene family encompasses at least 6 and possibly 10-20 members, all of which appear to be clustered in the genome. Analysis of interspecific backcross mice indicates that the genes encoding the three mouse stefins all map to mouse chromosome 16, a localization that is consistent with the recent assignment of the human stefin A gene to a region of conserved homology between human chromosome 3q and the proximal region of mouse chromosome 16.     

Growth and analysis of crystal forms of toxic shock syndrome toxin 1

Native toxic shock syndrom toxin 1 (TSST-1) purified from Staphylococcus aurius has been crystallized in four different forms. The highest resolution data (2.05 Å) was collected from orthorhombic crystals belonging to the space group C222₁. The unit cell dimension are a = 108.7 Å, b = 177.5 Å, c = 97.6 Å. Rotation function analysis of this from indicates that there is trimer of toxin molecules in the asymmetric unit with a local 3-fold axis parallel to the crystallographic c axis. Crystals of a double mutant of TSST-1 have been grown which has a single molecule in the asymmetric unit and diffract to 1.9 Å. The space group is P2₁ with unit cell parameters of a = 44.4 Å, b = 34.0 Å, c = 55.2 Å, β = 93.0°. © 1993 Wiley-Liss, Inc.     

PRELIMINARY INFERENCES OF THE PHYLOGENY OF BRYOPHYTES FROM NUCLEAR-ENCODED RIBOSOMAL RNA SEQUENCES

Ribosomal RNA sequences and cladistic analysis were used to infer a phylogeny for eight bryophyte taxa. Portions of the cytoplasmic large (26S-like) and small (18S-like) subunit ribosomal RNA genes were sequenced for three marchantioid liverworts (Asterella, Conocephalum, and Riccia), three mosses (Atrichum, Fissidens, and Plagiomnium), and two hornworts (Phaeoceros and Notothylas). Cladistic analysis of these data suggests that the hornworts are the sister group to the mosses, the mosses and hornworts form a clade that is sister to the tracheophytes, and the liverworts form a clade sister to the other land plants. These results differ from previous cladistic analyses based on morphology, ultrastructure, and biochemistry, wherein the mosses alone are sister group to the tracheophytes. We conclude that cladistic analysis of molecular data can provide an independent data set for the study of bryophyte phylogeny, but the differences between the molecular and morphological results are a topic for further investigation.     

LYCOSPORA FROM CARBONIFEROUS LEPIDOSTROBUS COMPRESSIONS

Spores were extracted from Carboniferous Lepidostrobus compressions in order to associate in situ microspores with dispersed species of Lycospora. Two hundred twenty-six cones were examined, of which 61 contained spores. Fertile cones came from the Westphalian D of England, Namurian B through Westphalian D of the Appalachian and Illinois basins, and the Westphalian D of the Western Interior. Cones were separated into species based on microspore and cone morphology. Lycospora trigonoreticulata was produced by Lepidostrobus princeps from Westphalian C-D rocks from Missouri, the Illinois Basin, and the Appalachian Basin. Lycospora rotunda was produced by Lepidostrobus sp. A from Westphalian A rocks of Alabama. Two cone species produced Lycospora torquifer: Lepidostrobus praelongus from the Westphalian D of Pennsylvania and Lepidostrobus variabilis from the Westphalian A and C of the Illinois and Appalachian basins. Lycospora punctata was produced by Lepidostrobus cf. squarrosus from the Westphalian D of England, the Appalachian Basin, and Illinois Basin. Lycospora noctuina was produced by Lepidostrobus haslingdenensis from the Namurian B/C of Illinois. Microspore species are differentiated primarily on the basis of size, cingulum structure and width, and ornamentation. Cone species differ in width and distal lamina size, shape, and attitude. Lycospora species isolated from clastic species of Lepidostrobus differ completely from those of coal-swamp species, confirming that lycopod trees from clastic environments represent biologically different species from those centered in coal swamps.     

The Mouse Spam1 maps to proximal Chromosome 6 and is a candidate for the sperm dysfunction in Rb(6.16)24Lub and Rb(6.15)lAld heterozygotes

We have determined the chromosomal localization of the murine gene encoding the 68-kDa sperm adhesion molecule 1, Spam1 or Ph-20. Using two independent approaches, fluorescence in situ hybridization (FISH) and interspecific backcross analysis, we show that Spam1 maps to proximal mouse Chromosome (Chr) 6. This map position is within the conserved linkage group corresponding to human Chr 7q, where the human homolog, SPAM 1, has been shown to map previously. Genetic mapping shows the gene to be very closely linked to Met, one of the most proximal loci on MMU 6. It thus places the gene near the centromere and the junction of the Rb(6.16)24Lub and Rb(6.15)1Ald translocations. The essential role of the Spam1 sperm antigen in mouse sperm-egg interactions and its gene location provide strong support for its candidacy as the gene involved in the dysfunction of mouse sperm bearing the Rb(6.16)24Lub or Rb(6.15)1Ald translocation. Received: 16 July 1996 / Accepted: 23 September 1996