Landscape profiling of PET depolymerases using a natural sequence cluster framework.

Enzymes capable of breaking down polymers have been identified from natural sources and developed for industrial use in plastic recycling. However, there are many potential starting points for enzyme optimization that remain unexplored. We generated a landscape of 170 lineages of 1894 polyethylene terephthalate depolymerase (PETase) candidates and performed profiling using sampling approaches with features associated with PET-degrading capabilities.

Three-directional engineering of IsPETase with enhanced protein yield, activity, and durability.

The mesophilic PETase from Ideonella sakaiensis (IsPETase) has been shown to exhibit high PET hydrolysis activity, but its low stability limits its industrial applications. Here, we developed a variant, Z1-PETase, with enhanced soluble protein yield and durability while maintaining or improving activity at lower temperatures. The selected Z1-PETase not only exhibited a 20-fold improvement in soluble protein yield compared to the previously engineered IsPETase (4p) variant, but also demonstrated a 30% increase in low-temperature activity at 40 °C, along with an 11 °C increase in its Tm value.

Discovery and rational engineering of PET hydrolase with both mesophilic and thermophilic PET hydrolase properties.

Excessive polyethylene terephthalate (PET) waste causes a variety of problems. Extensive research focused on the development of superior PET hydrolases for PET biorecycling has been conducted. However, template enzymes employed in enzyme engineering mainly focused on IsPETase and leaf-branch compost cutinase, which exhibit mesophilic and thermophilic hydrolytic properties, respectively.

Crystal Structure and Functional Characterization of Acetylornithine Aminotransferase from .

The amino acids l-arginine and l-ornithine are widely used in animal feed and as health supplements and pharmaceutical compounds. In arginine biosynthesis, acetylornithine aminotransferase (AcOAT) uses pyridoxal-5'-phosphate (PLP) as a cofactor for amino group transfer. Here, we determined the crystal structures of the apo and PLP complex forms of AcOAT from (AcOAT).

Biochemical properties and crystal structure of isocitrate lyase from Bacillus cereus ATCC 14579.

The glyoxylate cycle is an important anabolic pathway and acts under a C compound (such as acetic acid) rich condition in bacteria. The isocitrate lyase (ICL) enzyme catalyzes the first step in the glyoxylate cycle, which is the cleavage of isocitrate to glyoxylate and succinate. This enzyme is a metalo-enzyme that contains an Mg or a Mnion at the active site for enzyme catalysis.