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39A SARS-CoV-2 vaccine is needed to control the global COVID-19 public health crisis. Atomic-40 level structures directed the application of prefusion-stabilizing mutations that improved 41 expression and immunogenicity of betacoronavirus spike proteins. Using this established 42 immunogen design, the release of SARS-CoV-2 sequences triggered immediate rapid 43 manufacturing of an mRNA vaccine expressing the prefusion-stabilized SARS-CoV-2 spike 44 trimer (mRNA-1273). Here, we show that mRNA-1273 induces both potent neutralizing antibody 45 and CD8 T cell responses and protects against SARS-CoV-2 infection in lungs and noses of 46 mice without evidence of immunopathology. mRNA-1273 is currently in a Phase 2 clinical trial 47 sequences (then known as "2019-nCoV") on January 10 th , the 2P mutations were substituted 98 into S positions aa986 and 987 to produce prefusion-stabilized SARS-CoV-2 S (S-2P) protein 99 for structural analysis 22 and serological assay development 23,24 in silico without additional 100 experimental validation. Within 5 days of sequence release, current Good Manufacturing 101

Microbial fermentation is an important technology for the conversion of renewable resources to chemicals. In this paper, we describe the application of metabolic engineering for the development of two new fermentation processes: the microbial conversion of sugars to 1,3-propanediol (1,3-PD) and 1,2-propanediol (1,2-PD). A variety of naturally occurring organisms ferment glycerol to 1,3-PD, but no natural organisms ferment sugars directly to 1,3-PD. We first describe the fed-batch fermentation of glycerol to 1,3-PD by Klebsiella pneumoniae. We then present various approaches for the conversion of sugars to 1,3-PD, including mixed-culture fermentation, cofermentation of glycerol and glucose, and metabolic engineering of a "sugars to 1,3-PD" pathway in a single organism. Initial results are reported for the expression of genes from the K. pneumoniae 1,3-PD pathway in Saccharomyces cerevisiae. The best naturally occurring organism for the fermentation of sugars to 1,2-PD is Thermoanaerobacterium thermosaccharolyticum. We describe the fermentation of several different sugars to 1,2-PD by this organism in batch and continuous culture. We report that Escherichia coli strains engineered to express either aldose reductase or glycerol dehydrogenase convert glucose to (R)-1,2-PD. We then analyze the ultimate potential of fermentation processes for the production of propanediols. Linear optimization studies indicate that, under aerobic conditions, propanediol yields that approach the theoretical maximum are possible and CO2 is the primary coproduct. Without the need to produce acetate, final product titers in the range of 100 g/L should be possible; the high titers and low coproduct levels should make product recovery and purification straightforward. The examples given in this paper illustrate the importance of metabolic engineering for fermentation process development in general.

uct characterization and release, production and purification processes that are scaleable and economical, and formulations enabling sufficient stability to guarantee an acceptable shelf-life. In this review, we highlight the many advances in these areas, and identify requirements for further research. In order to capture a comprehensive and current picture, we emphasize both the published and patent literature.We begin by discussing the common methods used for analysis of both purified and unpurified adenovirus (AdV) samples. These methods are critical to both process development and the release of GMP (good manufacturing practices) supplies to be used in clinical studies, and are referred to throughout the remainder of the review. Next, we discuss the options and rationale for vector design, and we describe the common complementing cell lines. Cultivation of AdV vectors including media selection, modes of operation (suspension vs. adherent, batch vs. fed-batch, and so on), and critical optimization and control parameters are then discussed, with an emphasis on current industrial practice. Adenovirus purification methodologies are addressed similarly, with a focus on the rational selection of unit operations for a scaleable process. Current industrial practices are compared, and critical issues such as the clearance of empty capsids and host cell DNA are reviewed in detail. Next, the development of remarkably stable liquid formulations is discussed, with an emphasis on excipient selection based on the mechanisms of inactivation. Finally, we briefly recap critical developments and highlight areas in need of additional research to support the next generation of adenovirus-based gene transfer products. 2Analytical methods for process and product characterization 2.1

1,2-Propanediol (1,2-PD) is a major commodity chemical that is currently derived from propylene, a nonrenewable resource. A goal of our research is to develop fermentation routes to 1,2-PD from renewable resources. Here we report the production of enantiomerically pure R-1,2-PD from glucose inEscherichia coli expressing NADH-linked glycerol dehydrogenase genes (E. coli gldA or Klebsiella pneumoniae dhaD). We also show that E. colioverexpressing the E. coli methylglyoxal synthase gene (mgs) produced 1,2-PD. The expression of either glycerol dehydrogenase or methylglyoxal synthase resulted in the anaerobic production of approximately 0.25 g of 1,2-PD per liter. R-1,2-PD production was further improved to 0.7 g of 1,2-PD per liter when methylglyoxal synthase and glycerol dehydrogenase (gldA) were coexpressed. In vitro studies indicated that the route to R-1,2-PD involved the reduction of methylglyoxal to R-lactaldehyde by the recombinant glycerol dehydrogenase and the reduction ofR-lactaldehyde to R-1,2-PD by a nativeE. coli activity. We expect that R-1,2-PD production can be significantly improved through further metabolic and bioprocess engineering.