Flying lemurs – The 'flying tree shrews'? Molecular cytogenetic evidence for a Scandentia-Dermoptera sister clade

Background  

Flying lemurs or Colugos (order Dermoptera) represent an ancient mammalian lineage that contains only two extant species. Although molecular evidence strongly supports that the orders Dermoptera, Scandentia, Lagomorpha, Rodentia and Primates form a superordinal clade called Supraprimates (or Euarchontoglires), the phylogenetic placement of Dermoptera within Supraprimates remains ambiguous.     

Sequence analysis of a chloroplast intergenic spacer for phylogenetic estimates in Allium section Cepa and a PCR-based polymorphism detecting mixtures of male-fertile and male-sterile cytoplasmic onion

Restriction-enzyme analysis of the chloroplast (cp) DNA yielded maternal phylogenies supporting a close phylogenetic relationship among normal (N) male-fertile and male-sterile (S) cytoplasmic bulb onion (Allium cepa), Allium altaicum, Allium fistulosum, Allium galanthum, Allium roylei, and Allium vavilovii. The S cytoplasm of onion is most likely an alien cytoplasm introduced in antiquity into onion populations. We previously showed that size differences in an intergenic spacer in the cp DNA distinguish N and S cytoplasms of onion. We cloned and sequenced this intergenic spacer from the N and S cytoplasms of onion, A. altaicum, A. fistulosum, A. galanthum, Allium pskemense, Allium oschaninii, A. roylei, and Allium ampeloprasm (outgroup) to identify the nature of previously described RFLPs and to develop a PCR-based marker revealing N-cytoplasmic contamination of S-cytoplasmic hybrid seed lots. Phylogenies based on restriction-enzyme analysis of the entire cp DNA were similar, but not identical, to those based on sequence divergence in this intergenic region. Received: 29 November 1999 / Accepted: 28 April 2000     

Production of cyclohexanone monooxygenase from Acinetobacter calcoaceticus for large scale Baeyer–Villiger monooxygenase reactions

Cyclohexanone monooxygenase was produced from Acinetobacter calcoaceticus grown on a medium containing both glutamate (30 g l^–1) and cyclohexanol (1 g l^–1). Productivity was increased to 650 U l^–1, an order of magnitude greater than previous production methods, thereby enhancing the potential commercial utility of this enzyme.     

Incidence of Clostridium botulinum in Crabmeat from the Blue Crab

The incidence of Clostridium botulinum in fresh crabmeat of blue crab was six out of 986 samples; in pasteurized crabmeat one sample out of 1,000 contained the organism.     

Hepatitis C Virus Phylogenetic Clustering Is Associated with the Social-Injecting Network in a Cohort of People Who Inject Drugs

It is hypothesized that social networks facilitate transmission of the hepatitis C virus (HCV). We tested for association between HCV phylogeny and reported injecting relationships using longitudinal data from a social network design study. People who inject drugs were recruited from street drug markets in Melbourne, Australia. Interviews and blood tests took place three monthly (during 2005–2008), with participants asked to nominate up to five injecting partners at each interview. The HCV core region of individual isolates was then sequenced and phylogenetic trees were constructed. Genetic clusters were identified using bootstrapping (cut-off: 70%). An adjusted Jaccard similarity coefficient was used to measure the association between the reported injecting relationships and relationships defined by clustering in the phylogenetic analysis (statistical significance assessed using the quadratic assignment procedure). 402 participants consented to participate; 244 HCV infections were observed in 238 individuals. 26 genetic clusters were identified, with 2–7 infections per cluster. Newly acquired infection (AOR = 2.03, 95% CI: 1.04–3.96, p = 0.037, and HCV genotype 3 (vs. genotype 1, AOR = 2.72, 95% CI: 1.48–4.99) were independent predictors of being in a cluster. 54% of participants whose infections were part of a cluster in the phylogenetic analysis reported injecting with at least one other participant in that cluster during the study. Overall, 16% of participants who were infected at study entry and 40% of participants with newly acquired infections had molecular evidence of related infections with at least one injecting partner. Likely transmission clusters identified in phylogenetic analysis correlated with reported injecting relationships (adjusted Jaccard coefficient: 0.300; p<0.001). This is the first study to show that HCV phylogeny is associated with the injecting network, highlighting the importance of the injecting network in HCV transmission.     

Export chaperone SecB uses one surface of interaction for diverse unfolded polypeptide ligands

SecB, a remarkable chaperone involved in protein export, binds diverse ligands rapidly with high affinity and low specificity. Site‐directed spin labeling and electron paramagnetic resonance spectroscopy were used to investigate the surface of interaction on the export chaperone SecB. We examined SecB in complex with the unfolded precursor form of outer membrane protein OmpA as well as with a truncated version of OmpA that includes the transmembrane domain and lacks both the signal peptide and the periplasmic domain. In addition, we studied the binding of SecB to the unfolded mature form of galactose‐binding protein, a soluble periplasmic protein. We have previously used the same strategy to map the binding surface for the precursor of galactose‐binding protein. We show that for all ligands tested the patterns of contact are the same.