Monomeric Esterase: Insights into Cooperative Behavior, Hysteresis/Allokairy.

Herein, we present a novel esterase enzyme, Ade1, isolated from a metagenomic library of Amazonian dark earths soils, demonstrating its broad substrate promiscuity by hydrolyzing ester bonds linked to aliphatic groups. The three-dimensional structure of the enzyme was solved in the presence and absence of substrate (tributyrin), revealing its classification within the α/β-hydrolase superfamily. Despite being a monomeric enzyme, enzymatic assays reveal a cooperative behavior with a sigmoidal profile (initial velocities vs substrate concentrations).

Characterization of () oligopeptidase B and its role in macrophage infection.

spp. are parasitic protozoa that cause leishmaniasis, a disease endemic in 98 countries. promastigotes are transmitted by the vector and differentiate into amastigotes within phagocytic cells of the vertebrate host.

Role of a high centrality residue in protein dynamics and thermal stability.

Centralities determined from Residue Interaction Networks (RIN) in proteins have been used to predict aspects of their structure and dynamics. Here, we correlate the Eigenvector Centrality (E) with the rate constant for thermal denaturation (k) of the HisF protein from Thermotoga maritima based on 12 single alanine substitution mutants. The molecular basis for this correlation was further explored by studying a mutant containing a replacement of a high E residue, Y182A, which displayed increased k at 80 °C.

Molecular Dynamics Reveals Complex Compensatory Effects of Ionic Strength on the Severe Acute Respiratory Syndrome Coronavirus 2 Spike/Human Angiotensin-Converting Enzyme 2 Interaction.

The SARS-CoV-2 pandemic has already killed more than one million people worldwide. To gain entry, the virus uses its Spike protein to bind to host hACE-2 receptors on the host cell surface and mediate fusion between viral and cell membranes. As initial steps leading to virus entry involve significant changes in protein conformation as well as in the electrostatic environment in the vicinity of the Spike/hACE-2 complex, we explored the sensitivity of the interaction to changes in ionic strength through computational simulations and surface plasmon resonance.

A novel β-glucosidase isolated from the microbial metagenome of Lake Poraquê (Amazon, Brazil).

The Amazon region holds most of the biological richness of Brazil. Despite their ecological and biotechnological importance, studies related to microorganisms from this region are limited. Metagenomics leads to exciting discoveries, mainly regarding non-cultivable microorganisms.

Biochemical Characterization and Low-Resolution SAXS Molecular Envelope of GH1 β-Glycosidase from Saccharophagus degradans.

The marine bacteria Saccharophagus degradans (also known as Microbulbifer degradans), are rod-shaped and gram-negative motile γ-proteobacteria, capable of both degrading a variety of complex polysaccharides and fermenting monosaccharides into ethanol. In order to obtain insights into structure-function relationships of the enzymes, involved in these biochemical processes, we characterized a S. degradans β-glycosidase from glycoside hydrolase family 1 (SdBgl1B).

The crystal structure of a lysozyme c from housefly Musca domestica, the first structure of a digestive lysozyme.

Lysozymes from family 22 of glycoside hydrolases are usually part of the defense system against bacteria. However in ruminant artiodactyls and saprophagous insects, lysozymes are involved in the digestion of bacteria. Here, we report the first crystallographic structure of a digestive lysozyme in its native and complexed forms, the structure of lysozyme 1 from Musca domestica larvae midgut (MdL1).