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Microbial biosynthetic gene clusters (BGCs) encoding secondary metabolites are thought to impact a plethora of biologically mediated environmental processes, yet their discovery and functional characterization in natural microbiomes remains challenging. Here we describe deep long-read sequencing and assembly of metagenomes from biological soil crusts, a group of soil communities that are rich in BGCs. Taking advantage of the unusually long assemblies produced by this approach, we recovered nearly 3,000 BGCs for analysis, including 712 full-length BGCs. Functional exploration through metatranscriptome analysis of a 3-day wetting experiment uncovered phylum-specific BGC expression upon activation from dormancy, elucidating distinct roles and complex phylogenetic and temporal dynamics in wetting processes. For example, a pronounced increase in BGC transcription occurs at night primarily in cyanobacteria, implicating BGCs in nutrient scavenging roles and niche competition. Taken together, our results demonstrate that long-read metagenomic sequencing combined with metatranscriptomic analysis provides a direct view into the functional dynamics of BGCs in environmental processes and suggests a central role of secondary metabolites in maintaining phylogenetically conserved niches within biocrusts. Marc Van Goethem et al. combine short- and long-read sequencing from biocrust samples to report nearly 3,000 biosynthetic gene clusters (BGCs) encoding microbial secondary metabolites. Their results demonstrate the advantage of integrated metatranscriptomic and long-read metagenomic sequencing in analyzing BGCs and provides insight into the role of secondary metabolites in maintaining phylogenetic niches in biocrusts. [ABSTRACT FROM AUTHOR]

Iotarphia rufobrunnea Lee & Ahn, sp. n. is described from Tasmania. The new species is compared with another species of the genus, I. australis Cameron. A description, habitus photograph and illustrations of the diagnostic characters are provided. [ABSTRACT FROM AUTHOR]

The article presents a study reporting the unexpected discovery that fish can synthesize gadusol de novo and that the analogous pathways are also present in amphibians, reptiles, and birds, while it shows that engineered yeast containing the fish genes can produce and secrete gadusol.

When designing a building intended to be resistant to progressive collapse, it is instructive to consider this problem from the point of view of an implosion contractor who regularly demolishes buildings through explosives-induced progressive failure. All buildings want to fall down, but are prevented from doing so through their structural columns, walls and transfer girders. Innumerable ergs of potential energy are just waiting to be released. The implosion contractor creates a progressive collapse by releasing this energy through the sequential explosive removal of key structural supports, allowing gravity to do the remaining work, simultaneously using the minimum amount of explosives, creating the maximum amount of fragmentation, and minimizing the potential fly of debris. In this paper, we will explore several building structural systems and how their implosion has historically been achieved, comparing the amount of effort required in each system to affect an implosion as related to the susceptibility of that type of building to progressive collapse and identifying those types that lend themselves to it. The building structural systems described represent actual case studies. By comparison of different systems from the implosion contractor’s perspective, the design engineer will gain unique knowledge about systems that are inherently resistant to progressive collapse. [ABSTRACT FROM AUTHOR]

Analyzes the rhyme scheme used in the literary style of poet Paul Muldoon. Evolution of fuzzy rhyme; Details on the principles of fuzzy rhyme; Analyses on semantic and strategic functions of two short poems in the literature `Meeting the British'; Implications of linguistic and cultural conquest for rhyming and allusiveness in the works of Muldoon.