Visualization and characterization of Enterococcus faecalis biofilm structure in bovine dentin using 2D and 3D microscopic techniques

Archives of Microbiology - Bacterial biofilms are related to various dental and periodontal infectious diseases, and the characterization of this biological structure with micro-computed tomography...     

Human naive epiblast cells possess unrestricted lineage potential

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The protein formula of beef heart cytochrome c oxidase

Beef heart cytochrome c oxidase consist of 12 different polypeptides stoichiometrically arranged in respiratory complex IV. The functional 2 heme a, 2 copper monomer of this complex consist of 1793 amino acids; the exact Mr is 202,787 Da. From 17 cysteine residues, six are involved in the formation of three disulphide bonds. The theoretical heme a content of the enzyme is 9.86 nmol/mg protein. The theoretical iron and copper contents are 0.55 and 0.63 microgram/mg protein, respectively.     

Enhancing structural complexity: An experiment conducted in the Black Forest National Park,Germany

We report on a structural complexity enhancement (SCE) experiment that was designed to test ecological restoration measures in the Black Forest National Park, Germany. The main goal was to understand as to whether the creation of standing and downed deadwood within previously managed, single-layered Norway spruce (Picea abies L.) forests accelerates the development of forest structure, richness, and diversity of a range of taxonomic groups. Here we introduce the experimental design and describe the development of stand structure including abundance and richness of tree-related microhabitats (TreMs) within 5 years after initiation of the experiment in October 2016. To enhance structural complexity in treatment plots, 10 trees per plot were toppled using a skidder winch, and another 10 trees were ring barked at a height of around 60 cm above ground level with a chainsaw. To monitor stand structure, we collected data on common forest attributes such as diameter at breast height (DBH), tree height, and TreMs of all trees in the six experimental and six control plots measuring 0.25 ha in size before the treatments were carried out in 2016 and again in 2020/21. We analyzed the abundance and richness of TreMs using generalized linear mixed models with DBH and treatment vs. control as predictors. The SCE treatment resulted in a significant increase in deadwood volumes (4.2 vs. 439.5 m³) as well as in TreM abundance and richness (increase of 0.74 TreMs per tree). This indicates that the SCE treatment was effective to increase biodiversity-relevant structures such as deadwood and TreMs, in previously managed Norway spruce-dominated stands. The ongoing monitoring of a range of taxonomic groups (birds, bats, small mammals, coleoptera, fungi, mosses, and vascular plants) in this experiment will demonstrate to what extent the enhancement in structural complexity will lead to an enrichment in species richness and diversity.     

Localization of lipid binding domain(s) on subunit II of beef heart cytochrome c oxidase

Photoactivatable arylazido phospholipids (Bisson, R., and Montecucco, C. (1981) Biochem. J. 193, 757-763) have been used to study the arrangement in the membrane of beef heart cytochrome c oxidase subunit II. Fragmentation of the photocross-linked polypeptide showed that sequence 20-98, which contains two long stretches of uncharged amino acid residues (Steffens, G. J., and Buse, G. (1979) Hoppe-Seyler's Z. Physiol. Chem. 360, 613-619), is in contact with lipids. Edman degradation of the labeled peptide indicated that His 26, Thr 27 and Met 29 are involved in the interaction with the polar head region of the bilayer. These data have been used to propose a scheme for the folding of subunit II in the mitochondrial membrane.