A High-Throughput Screening Platform for Engineering Poly(ethylene Terephthalate) Hydrolases.

The ability of enzymes to hydrolyze the ubiquitous polyester, poly(ethylene terephthalate) (PET), has enabled the potential for bioindustrial recycling of this waste plastic. To date, many of these PET hydrolases have been engineered for improved catalytic activity and stability, but current screening methods have limitations in screening large libraries, including under high-temperature conditions. Here, we developed a platform that can simultaneously interrogate PET hydrolase libraries of 10-10 variants (per round) for protein solubility, thermostability, and activity via paired, plate-based split green fluorescent protein and model substrate screens.

Toward a Predictive Understanding of Cyanobacterial Harmful Algal Blooms through AI Integration of Physical, Chemical, and Biological Data.

Freshwater cyanobacterial harmful algal blooms (cyanoHABs) are a worldwide problem resulting in substantial economic losses, due to harm to drinking water supplies, commercial fishing, wildlife, property values, recreation, and tourism. Moreover, toxins produced from some cyanoHABs threaten human and animal health. Climate warming can affect the distribution of cyanoHABs, where rising temperatures facilitate more intense blooms and a greater distribution of cyanoHABs in inland freshwater.

Biodegradation Studies of Polyhydroxybutyrate and Polyhydroxybutyrate--Polyhydroxyvalerate Films in Soil.

Due to increased environmental pressures, significant research has focused on finding suitable biodegradable plastics to replace ubiquitous petrochemical-derived polymers. Polyhydroxyalkanoates (PHAs) are a class of polymers that can be synthesized by microorganisms and are biodegradable, making them suitable candidates. The present study looks at the degradation properties of two PHA polymers: polyhydroxybutyrate (PHB) and polyhydroxybutyrate--polyhydroxyvalerate (PHBV; 8 wt.

Nonclassical autophagy activation pathways are essential for production of infectious Influenza A virus in vitro.

Autophagy is a critical mechanism deployed by eukaryotic cells in response to stress, including viral infection, to boost the innate antimicrobial responses. However, an increasing number of pathogens hijack the autophagic machinery to facilitate their own replication. Influenza A virus (IAV), responsible for several global pandemics, has an intricate dependence on autophagy for successful replication in mammalian cells.

Inhibition of DNA Methylation in Alters Algae Productivity.

Eukaryotic organisms regulate the organization, structure, and accessibility of their genomes through chromatin remodeling that can be inherited as epigenetic modifications. These DNA and histone protein modifications are ultimately responsible for an organism's molecular adaptation to the environment, resulting in distinctive phenotypes. Epigenetic manipulation of algae holds yet untapped potential for the optimization of biofuel production and bioproduct formation; however, epigenetic machinery and modes-of-action have not been well characterized in algae.

Mispacking and the Fitness Landscape of the Green Fluorescent Protein Chromophore Milieu.

The autocatalytic maturation of the chromophore in green fluorescent protein (GFP) was thought to require the precise positioning of the side chains surrounding it in the core of the protein, many of which are strongly conserved among homologous fluorescent proteins. In this study, we screened for green fluorescence in an exhaustive set of point mutations of seven residues that make up the chromophore microenvironment, excluding R96 and E222 because mutations at these positions have been previously characterized. Contrary to expectations, nearly all amino acids were tolerated at all seven positions.

Toward Computationally Designed Self-Reporting Biosensors Using Leave-One-Out Green Fluorescent Protein.

Leave-one-out green fluorescent protein (LOOn-GFP) is a circularly permuted and truncated GFP lacking the nth β-strand element. LOO7-GFP derived from the wild-type sequence (LOO7-WT) folds and reconstitutes fluorescence upon addition of β-strand 7 (S7) as an exogenous peptide. Computational protein design may be used to modify the sequence of LOO7-GFP to fit a different peptide sequence, while retaining the reconstitution activity.

Exploring the folding pathway of green fluorescent protein through disulfide engineering.

We have introduced two disulfide crosslinks into the loop regions on opposite ends of the beta barrel in superfolder green fluorescent protein (GFP) in order to better understand the nature of its folding pathway. When the disulfide on the side opposite the N/C-termini is formed, folding is 2× faster, unfolding is 2000× slower, and the protein is stabilized by 16 kJ/mol. But when the disulfide bond on the side of the termini is formed we see little change in the kinetics and stability.

The role of cross-chain ionic interactions for the stability of collagen model peptides.

The contribution of ionic interactions to the stability of the collagen triple helix was studied using molecular dynamics (MD) simulations and biophysical methods. To this end, we examined the stability of a host-guest collagen model peptide, Ac-GPOGPOGPYGXOGPOGPO-NH2, substituting KGE, KGD, EGK, and DGK for the YGX sequence. All-atom, implicit solvent MD simulations show that the fraction of cross-chain ionic interactions formed is different, with the most pronounced in the KGE and KGD sequences, and the least in the DGK sequence.