Differentiation of Coll plasmids by ability to cause abortive infection of bacteriophages BF23 and T5

Eight strains, comprising all recognized species of Cellulomonas , were subjected to 51 different biochemical tests on four occasions. For 32 of these tests, a mixture of positive and negative results was obtained and from these data as few as six commonly used biochemical tests (glucose, indole, lactose, ONPG, nitrate and lysine) permit separation of the species of the genus Cellulomonas . A tentative simplified schema or dichotomous key is proposed.     

A mitochondrial genome phylogeny of Diptera: whole genome sequence data accurately resolve relationships over broad timescales with high precision

Abstract Mitochondrial genomes provide a promising new tool for understanding deep‐level insect phylogenetics, but have yet to be evaluated for their ability to resolve intraordinal relationships. We tested the utility of mitochondrial genome data for the resolution of relationships within Diptera, the insect order for which the most data are available. We sequenced an additional three genomes, from a syrphid, nemestrinid and tabanid, representing three additional dipteran clades, ‘aschiza’, non‐heteroneuran muscomorpha and ‘basal brachyceran’, respectively. We assessed the influence of optimality criteria, gene inclusion/exclusion, data recoding and partitioning strategies on topology and nodal support within Diptera. Our consensus phylogeny of Diptera was largely consistent with previous phylogenetic hypotheses of the order, except that we did not recover a monophyletic Muscomorpha (Nesmestrinidae grouped with Tabanidae) or Acalyptratae (Drosophilidae grouped with Calliphoridae). The results were very robust to optimality criteria, as parsimony, likelihood and Bayesian approaches yielded very similar topologies, although nodal support varied. The addition of ribosomal and transfer RNA genes to the protein coding genes traditionally used in mitochondrial genome phylogenies improved the resolution and support, contrary to previous suggestions that these genes would evolve too quickly or prove too difficult to align to provide phylogenetic signal at deep nodes. Strategies to recode data, aimed at reducing homoplasy, resulted in a decrease in tree resolution and branch support. Bayesian analyses were highly sensitive to partitioning strategy: biologically realistic partitions into codon groups produced the best results. The implications of this study for dipteran systematics and the effective approaches to using mitochondrial genome data are discussed. Mitochondrial genomes resolve intraordinal relationships within Diptera accurately over very wide time ranges (1–200 million years ago) and genetic distances, suggesting that this may be an excellent data source for deep‐level studies within other, less studied, insect orders.     

NEUROENDOCRINE REGULATION OF PROTEIN ACCUMULATION BY THE TRANSPARENT ACCESSORY REPRODUCTIVE GLAND OF MALE RHODNIUS PROLIXUS

Surgical removal of the corpus allatum or neurosecretory cells of the brain results in a marked reduction in protein accumulation in the transparent accessory reproductive gland (TARG) of the male. Topical application of C₁₈ juvenile hormone stimulates a dose-dependent accumulation of protein in allatectomized males. These results suggest that a direct or indirect stimulation by the neuroendocrine system is normally required for TARG protein synthesis.     

Epidemic strains of Salmonella agona differentiated by phage restriction and u. v.-protection markers on Collb plasmids

Genes for phage restriction and u. v.-protection, carried by some Coll plasmids, are useful markers of plasmids carried by host bacteria. Colicinogeny, with associated marker characters, may prove useful for strain differentiation as it did, in this study, with strains of Salmonella agona involved in an outbreak.     

Phylogeography and ecological niche modelling implicate coastal refugia and trans‐alpine dispersal of a New Zealand fungus beetle

The Last Glacial Maximum (LGM) severely restricted forest ecosystems on New Zealand’s South Island, but the extent of LGM distribution for forest species is still poorly understood. We used mitochondrial DNA phylogeography (COI) and ecological niche modelling (ENM) to identify LGM refugia for the mycophagous beetle Agyrtodes labralis (Leiodidae), a forest edge species widely distributed in the South Island. Both the phylogenetic analyses and the ENM indicate that A. labralis refuged in Kaikoura, Nelson, and along much of the South Island’s west coast. Phylogeography of this species indicates that recolonization of the largely deforested east and southeast South Island occurred in a west–east direction, with populations moving through the Southern Alps, and that the northern refugia participated little in interglacial population expansion. This contradicts published studies of other New Zealand species, in which recolonization occurs in a north–south fashion from many of the same refugia.