Fluorescent and Bioluminescent Calcium Indicators with Tuneable Colors and Affinities.

We introduce a family of bright, rhodamine-based calcium indicators with tuneable affinities and colors. The indicators can be specifically localized to different cellular compartments and are compatible with both fluorescence and bioluminescence readouts through conjugation to HaloTag fusion proteins. Importantly, their increase in fluorescence upon localization enables no-wash live-cell imaging, which greatly facilitates their use in biological assays.

Kinetic and Structural Characterization of the Self-Labeling Protein Tags HaloTag7, SNAP-tag, and CLIP-tag.

The self-labeling protein tags (SLPs) HaloTag7, SNAP-tag, and CLIP-tag allow the covalent labeling of fusion proteins with synthetic molecules for applications in bioimaging and biotechnology. To guide the selection of an SLP-substrate pair and provide guidelines for the design of substrates, we report a systematic and comparative study of the labeling kinetics and substrate specificities of HaloTag7, SNAP-tag, and CLIP-tag. HaloTag7 reaches almost diffusion-limited labeling rate constants with certain rhodamine substrates, which are more than 2 orders of magnitude higher than those of SNAP-tag for the corresponding substrates.

Site-Specific Conjugation of Native Antibodies Using Engineered Microbial Transglutaminases.

Site-specific bioconjugation technologies are frequently employed to generate homogeneous antibody-drug conjugates (ADCs) and are generally considered superior to stochastic approaches like lysine coupling. However, most of the technologies developed so far require undesired manipulation of the antibody sequence or its glycan structures. Herein, we report the successful engineering of microbial transglutaminase enabling efficient, site-specific conjugation of drug-linker constructs to position HC-Q295 of native, fully glycosylated IgG-type antibodies.

Helicobacter pylori genome evolution during human infection.

High genetic diversity is a hallmark of the gastric pathogen Helicobacter pylori. We used 454 sequencing technology to perform whole-genome comparisons for five sets of H. pylori strains that had been sequentially cultured from four chronically infected Colombians (isolation intervals=3-16 y) and one human volunteer experimentally infected with H.

Laser printing of skin cells and human stem cells.

Laser printing based on laser-induced forward transfer (LIFT) is a new biofabrication technique for the arrangement of biological materials or living cells in well-defined patterns. In the current study, skin cell lines (fibroblasts/keratinocytes) and human mesenchymal stem cells (hMSC) were chosen for laser printing experiments due to their high potential in regeneration of human skin and new application possibilities of stem cell therapy. To evaluate the influence of LIFT on the cells, their survival rate, their proliferation and apoptotic activity, and the DNA damages and modifications of their cell surface markers were assessed and statistically evaluated over several days.

pH effect on the susceptibility to parasitoid infection in the marine diatom spp. (Bacillariophyceae).

The pH on the frustule of individual cells of the marine centric diatoms and (Bacillariophyceae) was measured with pH microsensors in culture media with increasing pH values of 8.04, 8.14, and 8.

Prevalence of pSmeSM11a-like plasmids in indigenous Sinorhizobium meliloti strains isolated in the course of a field release experiment with genetically modified S. meliloti strains.

Plasmid pSmeSM11a, residing in the indigenous Sinorhizobium meliloti strain SM11 originating from a field in Strassmoos (Bavaria, Germany), was analysed previously at the genomic level. Thirty-seven indigenous S. meliloti strains, originating from two different locations in Germany, were screened for genes identified previously on pSmeSM11a.

Photosynthetic oscillation in individual cells of the marine diatom Coscinodiscus wailesii (Bacillariophyceae) revealed by microsensor measurements.

Oscillations with a period of 1-2 min in the rate of photosynthesis have been found in leaves of C(3 )and C(4 )land plants under invariant, saturating, light and carbon dioxide. This article reports the occurrence of similar oscillations with a period of 2-2.5 min in individual cells of the marine diatom Coscinodiscus wailesii.

The systematic position of the parasitoid marine dinoflagellate Paulsenella vonstoschii (Dinophyceae) inferred from nuclear-encoded small subunit ribosomal DNA.

Members of the genus Paulsenella Chatton are marine phagotrophic dinoflagellates that specifically attack marine diatoms. In this phylogenetic study, we show that Paulsenella groups with Amyloodinium ocellatum (Brown) Brown et Hovasse, Pfiesteria piscicida Steidinger et Burkholder (Dinophyceae), Pfiesteria shumwayae Glasgow et Burkholder, and the cryptoperidiniopsoids, all members of the order Peridiniales. In the phylogenetic tree, Paulsenella diverged after Amyloodinium ocellatum but prior to Pfiesteria and the cryptoperidiniopsoids.

Phylogenetic position of the parasitoid nanoflagellate Pirsonia inferred from nuclear-encoded small subunit ribosomal DNA and a description of Pseudopirsonia n. gen. and Pseudopirsonia mucosa (Drebes) comb. nov.

Sequences of the nuclear encoded small subunit (SSU) rRNA were determined for Pirsonia diadema, P. guinardiae, P. punctigerae, P.