Paper mulberry (Broussonetia papyrifera) as a commensal model for human mobility in Oceania: anthropological, botanical and genetic considerations

Paper mulberry (Broussonetia papyrifera (L.) Vent.) was one of the most widely distributed crop species in prehistoric Oceania, occurring from continental East Asia to the Polynesian islands. Its broad distribution is largely due to human-mediated dispersal during colonization of the islands of Near and Remote Oceania. We explore the potential for analyses of genetic variation in paper mulberry and the value of such data for the development of a new commensal model species for reconstructing patterns of human mobility in Oceania. We introduce and discuss paper mulberry as another commensal species and outline key features for its contribution to the understanding of human migration and post-colonization interaction. Here, we describe some of the extant B. papyrifera populations in Remote Oceania and Taiwan that were sampled for initial studies. We argue that the unique characteristics of this species and its importance in ancient Pacific island societies may provide the opportunity to collect valuable genetic data with which we can address several key questions in Pacific prehistory

Anisotropic intermediate valence in Yb2Rh3Ga9

We report measurements of the inelastic neutron scattering spectrum for the anisotropic intermediate valence system Yb2Rh3Ga9. Calculations for the Anderson impurity model with crystal field terms within an approach based on the non-crossing approximation have been performed for the inelastic neutron scattering spectrum as well as other thermodynamic quantities. These results corroborate the importance of crystal field effects in these materials. They also suggest that Anderson lattice effects are important to the physics of Yb2Rh3Ga9.<br/

Anisotropic intermediate valence in Yb2M3Ga9 (M = Rh, Ir)

The intermediate valence compounds Yb2M3Ga9 (M = Rh, Ir) exhibit an anisotropic magnetic susceptibility. We report measurements of the temperature dependence of the 4f occupation number, nf(T), for Yb2M3Ga9 as well as the magnetic inelastic neutron scattering spectrum Smag at 12 and 300 K for Yb2Rh3Ga9. Both nf(T) and Smag were calculated for the Anderson impurity model with crystal field terms within an approach based on the non-crossing approximation. These results corroborate the importance of crystal field effects in these materials; they also suggest that Anderson lattice effects are important to the physics of Yb2M3Ga9.Comment: 17 pages, 3 figures, submitted to Phys. Rev.

Comparative genomics of Ceriporiopsis subvermispora and Phanerochaete chrysosporium provide insight into selective ligninolysis

6 páginas, 3 figuras, 3 tablas -- PAGS nros. 5458-5463 et al.Efficient lignin depolymerization is unique to the wood decay basidiomycetes, collectively referred to as white rot fungi. Phanerochaete chrysosporium simultaneously degrades lignin and cellulose, whereas the closely related species, Ceriporiopsis subvermispora, also depolymerizes lignin but may do so with relatively little cellulose degradation. To investigate the basis for selective ligninolysis, we conducted comparative genome analysis of C. subvermispora and P. chrysosporium. Genes encoding manganese peroxidase numbered 13 and five in C. subvermispora and P. chrysosporium, respectively. In addition, the C. subvermispora genome contains at least seven genes predicted to encode laccases, whereas the P. chrysosporium genome contains none. We also observed expansion of the number of C. subvermispora desaturase-encoding genes putatively involved in lipid metabolism. Microarray-based transcriptome analysis showed substantial up-regulation of several desaturase and MnP genes in wood-containing medium. MS identified MnP proteins in C. subvermispora culture filtrates, but none in P. chrysosporium cultures. These results support the importance of MnP and a lignin degradation mechanism whereby cleavage of the dominant nonphenolic structures is mediated by lipid peroxidation products. Two C. subvermispora genes were predicted to encode peroxidases structurally similar to P. chrysosporium lignin peroxidase and, following heterologous expression in Escherichia coli, the enzymes were shown to oxidize high redox potential substrates, but not Mn2+. Apart from oxidative lignin degradation, we also examined cellulolytic and hemicellulolytic systems in both fungi. In summary, the C. subvermispora genetic inventory and expression patterns exhibit increased oxidoreductase potential and diminished cellulolytic capability relative to P. chrysosporiumThe major portions of this work were performed under US Department of Agriculture Cooperative State, Research, Education, and Extension Service Grant 2007-35504-18257 (to D.C. and R.A.B.). The US Department of Energy Joint Genome Institute is supported by the Office of Science of the US Department of Energy under Contract DE-AC02-05CH11231. This work was supported by Spanish Projects BIO2008-01533 and BIO2011-26694, European Project Peroxidases as Biocatalysts KBBE-2010-4-265397 (to F.J.R.-D. and A.T.M.), the Chilean National Fund for Scientific and Technological Development Grant 1090513 (to L.F.L.), and a “Ramon y Cajal” contract (to F.J.R.-D.)Peer reviewe