Thermostable enzymes and thermophilic cell factories may afford economic advantages inFurthermore, we present evidence suggesting that aside from representing a potential 9 reservoir of thermostable enzymes, thermophilic fungi are amenable to manipulation using 10 classical and molecular genetics. 11Rapid, efficient and robust enzymatic degradation of biomass-derived polysaccharides is 12 currently a major challenge for biofuel production. A prerequisite is the availability of enzymes 13 that hydrolyze cellulose, hemicellulose and other polysaccharides into fermentable sugars at 14 conditions suitable for industrial use. The best studied and most widely used cellulases and to overcome these obstacles is to raise the reaction temperature, thereby increasing hydrolytic 20 rates and reducing contamination risks. AT-rich repetitive regions (Fig. 1) To examine the strategy used by these thermophiles for decomposition of plant cell wall 9 polysaccharides, we used RNA-Seq to compare transcript profiles during growth on barley straw 10 or alfalfa straw to growth on glucose. Alfalfa was chosen to represent dicotyledonous plants, 11 whereas barley was used to represent monocotyledon plants. The major difference between these 12 materials is that the carbohydrates from barley cell wall are mainly cellulose and hemicellulose 13 with a negligible amount of pectin 11 , whereas alfalfa cell wall contains pectin and xylan in 14 roughly similar proportions, each consisting of 15-20% of total carbohydrates 12, . 15 We observed notable differences between the transcriptional profiles of genes encoding conditions. For example, the orthologs in Clades A, B, E, G and P of GH61 are upregulated 8 under growth in complex substrates for both thermophiles (Fig. 2b). An even more striking 9 correlation between transcript levels and orthologs is evident for the GH6 and GH7 cellulases 10 ( Supplementary Fig. 7) where the transcript profiles for the orthologs of the two organisms are Table 7). Thermophilic fungi are major components of the microflora in self-heating composts. They 9 break down cellulose at a faster rate than prodigious, mesophilic cellulase producers such as T. Tables 11-14). On the basis of 24 our comparative analyses of the genomes from two thermophilic fungi, we conclude that their 25 nucleotide and protein features are different from those observed in thermophilic prokaryotes. 26 We also investigated the possibility that thermophilic fungi possess major differences in 27 processes mediating thermophily including heat shock, oxidative stress, membrane biosynthesis, 28 chromatin structure and modification, and fungal cell wall metabolism. We compared the 29 proteins predicted to be involved in these processes in C. globosum, M. thermophila and T. 30 terrestris, but were unable to find differences that can convincingly be interpreted as the Fig. 9). Within the Sordiariales, thermophily 6 is restricted to subgroups of the family Chaetomiaceae. Among fungi more broadly, thermophily 7 also exists in the Zygomycota, but it ...

Thermostable enzymes and thermophilic cell factories may afford economic advantages inFurthermore, we present evidence suggesting that aside from representing a potential 9 reservoir of thermostable enzymes, thermophilic fungi are amenable to manipulation using 10 classical and molecular genetics. 11Rapid, efficient and robust enzymatic degradation of biomass-derived polysaccharides is 12 currently a major challenge for biofuel production. A prerequisite is the availability of enzymes 13 that hydrolyze cellulose, hemicellulose and other polysaccharides into fermentable sugars at 14 conditions suitable for industrial use. The best studied and most widely used cellulases and to overcome these obstacles is to raise the reaction temperature, thereby increasing hydrolytic 20 rates and reducing contamination risks. AT-rich repetitive regions (Fig. 1). one PL3 and two GH28). Pectin lyases are most active at neutral to alkaline pH whereas GH28 To examine the strategy used by these thermophiles for decomposition of plant cell wall 9 polysaccharides, we used RNA-Seq to compare transcript profiles during growth on barley straw 10 or alfalfa straw to growth on glucose. Alfalfa was chosen to represent dicotyledonous plants, 11 whereas barley was used to represent monocotyledon plants. The conditions. For example, the orthologs in Clades A, B, E, G and P of GH61 are upregulated 8 under growth in complex substrates for both thermophiles (Fig. 2b). An even more striking 9 correlation between transcript levels and orthologs is evident for the GH6 and GH7 cellulases Table 7). 14 Secretomes and exo-proteomes 15In addition to extracellular CAZymes involved in digestion of polysaccharide nutrients, the Thermophilic fungi are major components of the microflora in self-heating composts. They 9 break down cellulose at a faster rate than prodigious, mesophilic cellulase producers such as T. Fig. 8 We also investigated the possibility that thermophilic fungi possess major differences in 27 processes mediating thermophily including heat shock, oxidative stress, membrane biosynthesis, 28 chromatin structure and modification, and fungal cell wall metabolism. We compared the 29 proteins predicted to be involved in these processes in C. globosum, M. thermophila and T. 30terrestris, but were unable to find differences that can convincingly be interpreted as the Fig. 9) Thermophilic fungi are ubiquitous organisms commonly found in decomposing organic matter. 25The biotechnological utility of these fungi has been recognized for many years. enzymes from the thermophiles exhibit higher hydrolytic capacity than their counterparts from 6 mesophiles at temperatures ranging from 30 °C to 60 °C (Fig. 3). One explanation is that the 7 enzymes from the thermophiles possess higher specific activity toward lignocellulosic biomass.8

As the push towards exascale hardware has increased the diversity of system architectures, performance portability has become a critical aspect for scientific software. We describe the Kokkos Performance Portable Programming Model that allows developers to write single source applications for diverse high-performance computing architectures. Kokkos provides key abstractions for both the compute and memory hierarchy of modern hardware. We describe the novel abstractions that have been added to Kokkos version 3 such as hierarchical parallelism, containers, task graphs, and arbitrary-sized atomic operations to prepare for exascale era architectures. We demonstrate the performance of these new features with reproducible benchmarks on CPUs and GPUs.

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Vegetative cells of the filamentous ascomycete Neurospora tetrasperma are typically heterokaryotic, possessing haploid nuclei of both A and a mating types. As a consequence, N. tetrasperma is self-fertile. This life cycle, referred to as pseudohomothallism, clearly derives from true heterothallism of the type exhibited by related species such as N. crassa. Occasional homokaryotic, single-mating-type (heterothallic) isolates occur; in the laboratory, such strains can be outcrossed. The potential for outcrossing in N. tetrasperma raises the question of how this organism avoids heterokaryon incompatibility. Heterokaryon incompatability in vegetatively growing fungi is controlled by multiple loci. Two strains must be identical at each het locus (11 in N. crassa) to form a stable heterokaryon. Prior to the present survey, it seemed plausible that N. tetrasperma avoids heterokaryon incompatibility by maintaining compatible allele combinations through continual selfing. A survey of het-c variation among wild-type isolates in this study demonstrated that N. tetrasperma outcrosses in nature and that such matings can result in incompatible combinations of het-c alleles. Whereas individual wild-type isolates are invariably homoallelic for het-c, closely related strains may possess functionally different het-c alleles, which predate the origin of N. tetrasperma. Therefore, pseudohomothallic ascomycetes such as N. tetrasperma face an apparent evolutionary dilemma: the benefits of outcrossing must be balanced against the fact that matings can produce unstable heterokaryons and disrupt the pseudohomothallic life cycle.