Three years of aerial field experiments with Bacillus thuringiensis plus chitinase formulation against the spruce budworm

From 1971 to 1973 several Bacillus thuringiensis formulations were tested in the field against larvae of the spruce budworm under various conditions of population and tree defoliation. The results showed B. thuringiensis treatments can be a weapon in the control of spruce budworm outbreaks and the beneficial effect of B. thuringiensis treatments appear to be prolonged over 1 or 2 years. A new compact formulation was developed making B. thuringiensis treatments more economical and competitive with chemical insecticides.     

Acidobacteria are active and abundant members of diverse atmospheric H2-oxidizing communities detected in temperate soils

Significant rates of atmospheric dihydrogen (H₂) consumption have been observed in temperate soils due to the activity of high-affinity enzymes, such as the group 1h [NiFe]-hydrogenase. We designed broadly inclusive primers targeting the large subunit gene (hhyL) of group 1h [NiFe]-hydrogenases for long-read sequencing to explore its taxonomic distribution across soils. This approach revealed a diverse collection of microorganisms harboring hhyL, including previously unknown groups and taxonomically not assignable sequences. Acidobacterial group 1h [NiFe]-hydrogenase genes were abundant and expressed in temperate soils. To support the participation of acidobacteria in H₂ consumption, we studied two representative mesophilic soil acidobacteria, which expressed group 1h [NiFe]-hydrogenases and consumed atmospheric H₂ during carbon starvation. This is the first time mesophilic acidobacteria, which are abundant in ubiquitous temperate soils, have been shown to oxidize H₂ down to below atmospheric concentrations. As this physiology allows bacteria to survive periods of carbon starvation, it could explain the success of soil acidobacteria. With our long-read sequencing approach of group 1h [NiFe]-hydrogenase genes, we show that the ability to oxidize atmospheric levels of H₂ is more widely distributed among soil bacteria than previously recognized and could represent a common mechanism enabling bacteria to persist during periods of carbon deprivation.Subject terms: Soil microbiology, Biodiversity, Bacterial physiology     

Orally administered HSV-specific transfer factor (TF) prevents genital or labial herpes relapses

Forty-four patients suffering from genital (22) and labial (22) herpes were orally treated with HSV-1/2-specific transfer factor(TF). TF was obtained by in vitro replication of a HSV-1/2-specific bovine dialysable lymphocyte extract. Treatment was administered bi-weekly the first 2 weeks, and then weekly for 6 months, most patients received 2–3 courses. The total observation period for all patients before treatment was 26660 days, with 544 relapses, and a relapse index of 61.2, whereas the cumulative observation period during and after treatment was 16945 days, with a total of 121 relapsing episodes and a cumulative RI of 21.4 (P<0.0001). Results were equally significant when the 2 groups of patients (labial and genital) were considered separately. These observations confirm previous results obtained with bovine HSV-specific TF, and warrant further studies to establish HSV-specific TF as a choice of treatment for preventing herpes recurrences.     

AIDS and transfer factor: Myths,certainties and realities

At the end of the 20th century, the triumph of biology is as indisputable as that of physics was at the end of the 19th century, and so is the might of the inductive thought. Virtually all diseases have been seemingly conquered and HIV, the cause of AIDS, has been fully described ten years after the onset of the epidemic. However, the triumph of biological science is far from being complete. The toll of several diseases, such as cancer, continues to rise and the pathogenesis of AIDS remains elusive. In the realm of inductive science, the dominant paradigm can seldom be challenged in a frontal attack, especially when it is apparently successful, and only what Kuhn calls “scientific revolutions” can overthrow it. Thus, it is hardly surprising that the concept of transfer factor is considered with contempt, and the existence of the moiety improbable: over forty years after the introduction of the concept, not only its molecular structure remains unknown, but also its putative mode of action contravenes dogmas of both immunology and molecular biology. And when facts challenge established dogmas, be in religion, philosophy or science, they must be suppressed. Thus, results of heterodox research become henceforth nisi — i.e., valid unless cause is shown for rescinding them, because they challenge the prevalent paradigm. However, when observations pertain to lethal disorders, their suppression in the name of dogmas may become criminal. Because of the failure of medical science to manage the AIDS pandemic, transfer factor, which has been successfully used for treating or preventing viral infections, may today overcome a priori prejudice and rejection more swiftly. In science, as in life, certainties always end up by dying, and Copernicus’ vision by replacing that of Ptolemy.     

Iron-mediated degradation of ribosomes under oxidative stress is attenuated by manganese

Protein biosynthesis is fundamental to cellular life and requires the efficient functioning of the translational machinery. At the center of this machinery is the ribosome, a ribonucleoprotein complex that depends heavily on Mg²⁺ for structure. Recent work has indicated that other metal cations can substitute for Mg²⁺, raising questions about the role different metals may play in the maintenance of the ribosome under oxidative stress conditions. Here, we assess ribosomal integrity following oxidative stress both in vitro and in cells to elucidate details of the interactions between Fe²⁺ and the ribosome and identify Mn²⁺ as a factor capable of attenuating oxidant-induced Fe²⁺-mediated degradation of rRNA. We report that Fe²⁺ promotes degradation of all rRNA species of the yeast ribosome and that it is bound directly to RNA molecules. Furthermore, we demonstrate that Mn²⁺ competes with Fe²⁺ for rRNA-binding sites and that protection of ribosomes from Fe²⁺-mediated rRNA hydrolysis correlates with the restoration of cell viability. Our data, therefore, suggest a relationship between these two transition metals in controlling ribosome stability under oxidative stress.     

The High Light Response in Arabidopsis Involves ABA Signaling between Vascular and Bundle Sheath Cells

Previously, it has been shown that Arabidopsis thaliana leaves exposed to high light accumulate hydrogen peroxide (H₂O₂) in bundle sheath cell (BSC) chloroplasts as part of a retrograde signaling network that induces ASCORBATE PEROXIDASE2 (APX2). Abscisic acid (ABA) signaling has been postulated to be involved in this network. To investigate the proposed role of ABA, a combination of physiological, pharmacological, bioinformatic, and molecular genetic approaches was used. ABA biosynthesis is initiated in vascular parenchyma and activates a signaling network in neighboring BSCs. This signaling network includes the Gα subunit of the heterotrimeric G protein complex, the OPEN STOMATA1 protein kinase, and extracellular H₂O₂, which together coordinate with a redox-retrograde signal from BSC chloroplasts to activate APX2 expression. High light–responsive genes expressed in other leaf tissues are subject to a coordination of chloroplast retrograde signaling and transcellular signaling activated by ABA synthesized in vascular cells. ABA is necessary for the successful adjustment of the leaf to repeated episodes of high light. This process involves maintenance of photochemical quenching, which is required for dissipation of excess excitation energy.     

Temporal and spatial constraints on community assembly during microbial colonization of wood in seawater

Wood falls on the ocean floor form chemosynthetic ecosystems that remain poorly studied compared with features such as hydrothermal vents or whale falls. In particular, the microbes forming the base of this unique ecosystem are not well characterized and the ecology of communities is not known. Here we use wood as a model to study microorganisms that establish and maintain a chemosynthetic ecosystem. We conducted both aquaria and in situ deep-sea experiments to test how different environmental constraints structure the assembly of bacterial, archaeal and fungal communities. We also measured changes in wood lipid concentrations and monitored sulfide production as a way to detect potential microbial activity. We show that wood falls are dynamic ecosystems with high spatial and temporal community turnover, and that the patterns of microbial colonization change depending on the scale of observation. The most illustrative example was the difference observed between pine and oak wood community dynamics. In pine, communities changed spatially, with strong differences in community composition between wood microhabitats, whereas in oak, communities changed more significantly with time of incubation. Changes in community assembly were reflected by changes in phylogenetic diversity that could be interpreted as shifts between assemblies ruled by species sorting to assemblies structured by competitive exclusion. These ecological interactions followed the dynamics of the potential microbial metabolisms accompanying wood degradation in the sea. Our work showed that wood is a good model for creating and manipulating chemosynthetic ecosystems in the laboratory, and attracting not only typical chemosynthetic microbes but also emblematic macrofaunal species.