Acceptor Subsite Mutants of NCC 2970 GtfB 4,3-α-Glucanotransferase Regulate the Ratio of (α1 → 3)/(α1 → 6) Linkages in Biosynthesized α-Glucans.

NCC 2970 GtfB (2970 GtfB) is the only characterized 4,3-α-glucanotransferase (4,3-α-GTase) in the glycoside hydrolase (GH) 70 family belonging to the GtfB subfamily. However, the mechanism for its (α1 → 3) linkage formation remains unclear, and the structural determinants of its linkage specificity remain to be explored. Here, sequence alignment and structural comparison were conducted to identify key amino acids that may be critical for linkage specificity.

Action and cooperation in alginate degradation by three enzymes from the human gut bacterium Bacteroides eggerthii DSM 20697.

Alginate is a polysaccharide consumed by humans in edible seaweed and different foods where it is applied as a texturizing hydrocolloid or in encapsulations of drugs and probiotics. While gut bacteria are found to utilize and ferment alginate to health-beneficial short-chain fatty acids, knowledge on the details of the molecular reactions is sparse. Alginates are composed of mannuronic acid (M) and its C-5 epimer guluronic acid (G).

Validation of smartwatch electrocardiogram intervals in children compared to standard 12 lead electrocardiograms.

Unlabelled: Lay people are now able to obtain one-lead electrocardiograms (ECG) using smartwatches, which facilitates documentation of arrhythmias. The accuracy of smartwatch derived ECG intervals has not been validated in children though. Home-based monitoring of ECG intervals using a smartwatch could improve monitoring of children, e.

Kinetics and mapping of Ca-driven calmodulin conformations on skeletal and cardiac muscle ryanodine receptors.

Calmodulin transduces [Ca] information regulating the rhythmic Ca cycling between the sarcoplasmic reticulum and cytoplasm during contraction and relaxation in cardiac and skeletal muscle. However, the structural dynamics by which calmodulin modulates the sarcoplasmic reticulum Ca release channel, the ryanodine receptor, at physiologically relevant [Ca] is unknown. Using fluorescence lifetime FRET, we resolve different structural states of calmodulin and Ca-driven shifts in the conformation of calmodulin bound to ryanodine receptor.

Tailor-Made α-Glucans by Engineering the Processivity of α-Glucanotransferases via Tunnel-Cleft Active Center Interconversions.

The function of polysaccharides is intimately associated with their size, which is largely determined by the processivity of transferases responsible for their synthesis. A tunnel active center architecture has been recognized as a key factor that governs processivity of several glycoside hydrolases (GHs), e.g.