Biochemical and Structural Characterization of a Novel Psychrophilic Laccase (Multicopper Oxidase) Discovered from 229 (ENOLAB 4002).

Recently, prokaryotic laccases from lactic acid bacteria (LAB), which can degrade biogenic amines, were discovered. A laccase enzyme has been cloned from , a very important LAB in winemaking, and it has been expressed in . This enzyme has similar characteristics to those previously isolated from LAB as the ability to oxidize canonical substrates such as 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,6-dimethoxyphenol (2,6-DMP), and potassium ferrocyanide K[Fe(CN)], and non-conventional substrates as biogenic amines.

Structural and functional insights underlying recognition of histidine phosphotransfer protein in fungal phosphorelay systems.

In human pathogenic fungi, receiver domains from hybrid histidine kinases (hHK) have to recognize one HPt. To understand the recognition mechanism, we have assessed phosphorelay from receiver domains of five hHKs of group III, IV, V, VI, and XI to HPt from Chaetomium thermophilum and obtained the structures of Ct_HPt alone and in complex with the receiver domain of hHK group VI. Our data indicate that receiver domains phosphotransfer to Ct_HPt, show a low affinity for complex formation, and prevent a Leu-Thr switch to stabilize phosphoryl groups, also derived from the structures of the receiver domains of hHK group III and Candida albicans Sln1.

Polyethersulfone (PES) Filters Improve the Recovery of spp. and Enhance Selectivity against Interfering Microorganisms in Water Samples.

In the analysis of water samples, the type of filtration membrane material can influence the recovery of species, although this issue has been poorly investigated. Filtration membranes (0.45 µm) from different materials and manufacturers (numbered as 1, 2, 3, 4, and 5) were compared: mixed cellulose esters (MCEs), nitrocellulose (NC), and polyethersulfone (PES).

Evolutionary analysis and structure modelling of the Rcs-repressor IgaA unveil a functional role of two cytoplasmic small β-barrel (SBB) domains.

The Rcs sensor system, comprising the RcsB/RcsC/RcsD and RcsF proteins, is used by bacteria of the order to withstand envelope damage. In non-stress conditions, Rcs is repressed by IgaA, a membrane protein with three cytoplasmic regions (cyt-1, cyt-2 and cyt-3). How the Rcs-IgaA axis evolved within has not been yet explored.

Use of Blood Powder (Ground and Irradiated) for the Manufacture of Chocolate Agar.

Chocolate agar (CA) is an enriched medium for the isolation and identification of fastidious bacteria. Defibrinated blood is used to manufacture CA, but this expensive product is not always affordable for companies in developing countries. Blood powder (BP) is potentially a cheaper alternative, although its pre-treatment using autoclaving can impair the quality of the media.