The massive worldwide spread of the SARS-CoV-2 virus is fueling the COVID-19 pandemic. Since the first whole-genome sequence was published in January 2020, a growing database of tens of thousands of viral genomes has been constructed. This offers opportunities to study pathways of molecular change in the expanding viral population that can help identify molecular culprits of virulence and virus spread. Here we investigate the genomic accumulation of mutations at various time points of the early pandemic to identify changes in mutationally highly active genomic regions that are occurring worldwide. We used the Wuhan NC_045512.2 sequence as a reference and sampled 15 342 indexed sequences from GISAID, translating them into proteins and grouping them by month of deposition. The per-position amino acid frequencies and Shannon entropies of the coding sequences were calculated for each month, and a map of intrinsic disorder regions and binding sites was generated. The analysis revealed dominant variants, most of which were located in loop regions and on the surface of the proteins. Mutation entropy decreased between March and April of 2020 after steady increases at several sites, including the D614G mutation site of the spike (S) protein that was previously found associated with higher case fatality rates and at sites of the NSP12 polymerase and the NSP13 helicase proteins. Notable expanding mutations include R203K and G204R of the nucleocapsid (N) protein inter-domain linker region and G251V of the viroporin encoded by ORF3a between March and April. The regions spanning these mutations exhibited significant intrinsic disorder, which was enhanced and decreased by the N-protein and viroporin 3a protein mutations, respectively. These results predict an ongoing mutational shift from the spike and replication complex to other regions, especially to encoded molecules known to represent major β-interferon antagonists. The study provides valuable information for therapeutics and vaccine design, as well as insight into mutation tendencies that could facilitate preventive control.

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The massive worldwide spread of the SARS-CoV-2 virus is fueling the COVID-19 pandemic. Since the first whole-genome sequence was published in January 2020, a growing database of tens of thousands of viral genomes has been constructed. This offers opportunities to study pathways of molecular change in the expanding viral population that can help identify molecular culprits of virulence and virus spread. Here we investigate the genomic accumulation of mutations at various time points of the early pandemic to identify changes in mutationally highly active genomic regions that are occurring worldwide. We used the Wuhan NC_045512.2 sequence as a reference and sampled 15,342 indexed sequences from GISAID, translating them into proteins and grouping them by month of deposition. The per-position amino acid frequencies and Shannon entropies of the coding sequences were calculated for each month, and a map of intrinsic disorder regions and binding sites was generated. The analysis revealed dominant variants, most of which were located in loop regions and on the surface of the proteins. Mutation entropy decreased between March and April of 2020 after steady increases at several sites, including the D614G mutation site of the spike (S) protein that was previously found associated with higher case fatality rates and at sites of the NSP 12 polymerase and the NSP13 helicase proteins. Notable expanding mutations include R203K and G204R of the nucleocapsid (N) protein inter-domain linker region and G251V of the viroporin encoded by ORF3a between March and April. The regions spanning these mutations exhibited significant intrinsic disorder, which was enhanced and decreased by the N-protein and viroporin 3a protein mutations, respectively. These results predict an ongoing mutational shift from the spike and replication complex to other regions, especially to encoded molecules known to represent major beta-interferon antagonists. The study provides valuable information for therapeutics and vaccine design, as well as insight into mutation tendencies that could facilitate preventive control.

Background and objectives Soft endosperm corn has better wet milling characteristics but is susceptible to breakage and fracture during transport. The objective of this study is to compare the millability of commodity corn with different endosperm hardness originating from different parts of the world and its economic impact on importers of corn for wet milling. Findings US commodity corn generally has a soft endosperm hardness compared to corn from South America as the observed broken corn and foreign material was 0.4–3.4% and higher than other commodity corn exported to the same country. US corn exported to different international markets showed 4–5% higher starch yield compared to South American corn exported to the same market. This translates to an additional revenue of 6.5–9 million USD/year for a 2540 MT/day wet mill plant. [Correction added on 13 April 2021, after first online publication: The value of yield corrected from 100 to 2540.] Conclusions The US commodity corn, despite higher breakage, has superior millability and gives higher starch yields compared to corn from other geographies resulting in improved profitability of corn wet milling plants. Significance and novelty Commodity corn has varying endosperm hardness depending on geography of origin which impacts wet mill starch yield. Corn physical properties were used as an indicator for determining endosperm hardness.

The utilization of fossil fuels as a source of energy has led to many concerns, including environmental issues. Biobased fuels such as ethanol are a promising alternative, producing 39% lower greenhouse gas emissions than gasoline (Lewandrowski et al., 2020). Perhaps, the United States Department of Agriculture projects this number to increase up to 50% by 2022 due to corn ethanol utilization at the current rate (Flugge et al., 2017). Hence, the motivation to replace fossil fuels with environmentally friendly renewable energy is crucial. In the year 2018, 5% of the total energy consumed by the transportation sector was from biofuels, while motor gasoline accounted for 54% (EIA, 2019). The window for biofuels to expand and replace gasoline is substantial, besides undeniable benefits.