Isolation of soil bacteria able to hydrolyze both organophosphate and carbamate pesticides

Two bacteria identified as Pseudomonas putida and Acinetobacter rhizosphaerae able to rapidly degrade the organophosphate (OP) fenamiphos (FEN) were isolated. Denaturating gradient gel electrophoresis analysis revealed that the two isolates were dominant members of the enrichment culture. Clone libraries further showed that bacteria belonging to α-, β-, γ-proteobacteria and Bacteroidetes were also present in the final enrichment but were not isolated. Both strains hydrolyzed FEN to fenamiphos phenol which was further transformed, only by P. putida. The two strains were using FEN as C and N source. Cross-feeding studies with other pesticides showed that P. putida degraded OPs with a P-O-C linkage and unexpectedly degraded the carbamates oxamyl and carbofuran being the first wild-type bacterial strain able to degrade both OPs and carbamates. The same isolate exhibited high bioremediation potential against spillage-level concentrations of aged residues of FEN and its oxidized derivatives.     

Small changes in timing of breeding among subarctic passerines over a 32‐year period

Many bird populations in temperate regions have advanced their timing of breeding in response to a warming climate in recent decades. However, long‐term trends in temperature differ geographically and between seasons, and so do responses of local breeding populations. Data on breeding bird phenology from subarctic and arctic passerine populations are scarce, and relatively little data has been recorded in open‐nesting species. We investigated the timing of breeding and its relationship to spring temperature of 14 mainly open‐nesting passerine species in subarctic Swedish Lapland over a period of 32 years (1984–2015). We estimated timing of breeding from the progress of post‐juvenile moult in mist‐netted birds, a new method exploring the fact that the progress of post‐juvenile moult correlates with age. Although there was a numerical tendency for earlier breeding in most species (on average ?0.09 days/year), changes were statistically significant in only three species (by ?0.16 to ?0.23 days/year). These figures are relatively low compared with what has been found in other long‐term studies but are similar to a few other studies in subarctic areas. Generally, annual hatching dates were negatively correlated with mean temperature in May. This correlation was stronger in long‐distance than in short‐distance migrants. Although annual temperatures at high northern latitudes have increased over recent decades, there was no long‐term increase in mean temperature in May over the study period at this subarctic site. This is probably the main reason why there were only small long‐term changes in hatching dates.     

Greatly reduced phylogenetic structure in the cultivated potato clade (Solanum section Petota pro parte)

Premise of the Study

The species boundaries of wild and cultivated potatoes are controversial, with most of the taxonomic problems in the cultivated potato clade. We here provide the first in‐depth phylogenetic study of the cultivated potato clade to explore possible causes of these problems.

Methods

We examined 131 diploid accessions, using 12 nuclear orthologs, producing an aligned data set of 14,072 DNA characters, 2171 of which are parsimony‐informative. We analyzed the data to produce phylogenies and perform concordance analysis and goodness‐of‐fit tests.

Key Results

There is good phylogenetic structure in clades traditionally referred to as clade 1+2 (North and Central American diploid potatoes exclusive of Solanum verrucosum), clade 3, and a newly discovered basal clade, but drastically reduced phylogenetic structure in clade 4, the cultivated potato clade. The results highlight a clade of species in South America not shown before, ‘neocardenasii’, sister to clade 1+2, that possesses key morphological traits typical of diploids in Mexico and Central America. Goodness‐of‐fit tests suggest potential hybridization between some species of the cultivated potato clade. However, we do not have enough phylogenetic signal with the data at hand to explicitly estimate such hybridization events with species networks methods.

Conclusions

We document the close relationships of many of the species in the cultivated potato clade, provide insight into the cause of their taxonomic problems, and support the recent reduction of species in this clade. The discovery of the neocardenasii clade forces a reevaluation of a hypothesis that section Petota originated in Mexico and Central America.     

Synergy between ajoene and ketoconazole in isolates of Microsporum canis. A preliminary study using fractional inhibitory concentration technique (FIC)

Fungal infections are probably the most frequent infectious diseases affecting human being. Resistance to different anti-fungal drugs, and their bioavailability in the infection site, represent a problem for treatment. Looking for effective solutions, combination of two or more antifungal drugs to obtain an additive effect or synergic effect that potent antifungal activity has been investigated. In this study, the effect (additive, antagonist or synergistic) of ajoene and ketoconazole combination was evaluated in the growth and proliferation of filamentous fungi. Interactions in vitro were investigated in three isolates of Microsporum canis through a preliminary study using micro dilution, according to recommendations of NCCLS M-38A, with several modifications. Results obtained for CIF of each isolates studied (CIF = 0.18 0.36 microM), demonstrate that exists a very potent synergistic effect, when they are combined, and it represents a hope for future clinic trials to treat resilient fungal infections caused by M. canis.     

Novel single-chain Fv' formats for the generation of immunoliposomes by site-directed coupling

Immunoliposomes generated by coupling of antibodies to the liposomal surface allow for an active targeting of entrapped compounds to diseased areas. Single-chain Fv fragments (scFv) represent the smallest part of an antibody containing the entire antigen-binding site. They can be coupled in a defined and site-directed manner through genetically engineered cysteine residues, for example, those added at the C-terminus. Here, we have performed a comparative analysis of various scFv' variants with cysteine residues present at the end of a C-terminal extension of varying length and composition (HC variants) or introduced in the linker sequence connecting the variable heavy and light chain domain (LC variants). Using a scFv fragment directed against fibroblast activation protein (FAP) as a model antibody, we could show that all variants can be employed for the generation of active immunoliposomes, although the presence of three additional cysteine residues in one scFv' molecule resulted in decreased binding of immunoliposomes compared to that of immunoliposomes generated with scFv' molecules containing only one additional cysteine residue. In order to further improve the scFv' format by reducing the number of additional amino acid residues, we also generated molecules with the hexahistidyl-tag incorporated into the linker sequence together with a cysteine residue either at position 1 or 3 of the linker sequence (LCH variants). These newly designed scFv' molecules may be particularly suitable for the generation of immunoliposomes and other antibody conjugates, limiting the number of additional residues in these antibody molecules to a minimum.     

Livestock drugs and disease: the fatal combination behind breeding failure in endangered bearded vultures

There is increasing concern about the impact of veterinary drugs and livestock pathogens as factors damaging wildlife health, especially of threatened avian scavengers feeding upon medicated livestock carcasses. We conducted a comprehensive study of failed eggs and dead nestlings in bearded vultures (Gypaetus barbatus) to attempt to elucidate the proximate causes of breeding failure behind the recent decline in productivity in the Spanish Pyrenees. We found high concentrations of multiple veterinary drugs, primarily fluoroquinolones, in most failed eggs and nestlings, associated with multiple internal organ damage and livestock pathogens causing disease, especially septicaemia by swine pathogens and infectious bursal disease. The combined impact of drugs and disease as stochastic factors may result in potentially devastating effects exacerbating an already high risk of extinction and should be considered in current conservation programs for bearded vultures and other scavenger species, especially in regards to dangerous veterinary drugs and highly pathogenic poultry viruses.     

AgRP Neurons Require Carnitine Acetyltransferase to Regulate Metabolic Flexibility and Peripheral Nutrient Partitioning

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