Simultaneous Genome Sequencing of and within a Syntrophic Mixture Reveals Unique Pili and Protein Interactions.

Strains of , 2-K, N2, and N3 are known to be composed of a syntrophic mixture of a green sulfur bacterium and a sulfur-reducing colorless component. Upon sequence analysis, the green sulfur photosynthetic bacterial component of strain N3 was dominant and was readily sequenced, but the less abundant sulfur-reducing bacterial component was apparent only when analyzed by metagenomic binning. Whole-genome comparison showed that the green bacterium belonged to the genus and apparently was a species for which there was no genome sequence on file.

Structure of ATP citrate lyase and the origin of citrate synthase in the Krebs cycle.

Across different kingdoms of life, ATP citrate lyase (ACLY, also known as ACL) catalyses the ATP-dependent and coenzyme A (CoA)-dependent conversion of citrate, a metabolic product of the Krebs cycle, to oxaloacetate and the high-energy biosynthetic precursor acetyl-CoA. The latter fuels pivotal biochemical reactions such as the synthesis of fatty acids, cholesterol and acetylcholine, and the acetylation of histones and proteins. In autotrophic prokaryotes, ACLY is a hallmark enzyme of the reverse Krebs cycle (also known as the reductive tricarboxylic acid cycle), which fixates two molecules of carbon dioxide in acetyl-CoA.

Structural dissection of Shewanella oneidensis old yellow enzyme 4 bound to a Meisenheimer complex and (nitro)phenolic ligands.

Shewanella oneidensis, a Gram-negative γ-proteobacterium with an extensive redox capacity, possesses four old yellow enzyme (OYE) homologs. Of these, Shewanella yellow enzyme 4 (SYE4) is implicated in resistance to oxidative stress. Here, we present a series of high-resolution crystal structures for SYE4 in the oxidized and reduced states, and in complex with phenolic ligands and the nitro-aromatic explosive picric acid.

N-glycan structures of β-HlH subunit of Helix lucorum hemocyanin.

The carbohydrate structures of molluscan hemocyanins have recently received particular interest due to their specific monosaccharide composition, as well as their immunostimulatory properties and application in clinical studies. For the first time, we investigated N-glycans of the structural subunit β-HlH of hemocyanin isolated from Helix lucorum. In total, 32 different glycans were enzymatically liberated and characterized by tandem mass spectrometry using a Q-Trap mass spectrometer.

Antimicrobial Activity of Molluscan Hemocyanins from Helix and Rapana Snails.

For the first time the antimicrobial activities of hemocyanins from the molluscs Rapana venosa (RvH) and Helix aspersa (HaH) have been tested. From the hemolymph of the garden snail H. aspersa one structural subunit (βc-HaH ) and eight functional units (FUs, βc-HaH-a to βc-HaH-h) were isolated, and their N-terminal sequences and molecular weights, ranging between 45 and 65 kDa, determined.