How Small Proteins Adjust the Metabolism of Cyanobacteria Under Stress: The Role of Small Proteins in Cyanobacterial Stress Responses.

Several recently discovered small proteins of less than 100 amino acids control important, but sometimes surprising, steps in the metabolism of cyanobacteria. There is mounting evidence that a large number of small protein genes have also been overlooked in the genome annotation of many other microorganisms. Although too short for enzymatic activity, their functional characterization has frequently revealed the involvement in processes such as signaling and sensing, interspecies communication, stress responses, metabolism, regulation of transcription and translation, and in the formation of multisubunit protein complexes.

Protein NirP1 regulates nitrite reductase and nitrite excretion in cyanobacteria.

When the supply of inorganic carbon is limiting, photosynthetic cyanobacteria excrete nitrite, a toxic intermediate in the ammonia assimilation pathway from nitrate. It has been hypothesized that the excreted nitrite represents excess nitrogen that cannot be further assimilated due to the missing carbon, but the underlying molecular mechanisms are unclear. Here, we identified a protein that interacts with nitrite reductase, regulates nitrogen metabolism and promotes nitrite excretion.

Treating Apnea of Prematurity.

Premature babies often suffer apnea of prematurity as a physiological consequence of an immature respiratory system. Hypercapnia may develop, and neonates with apnea of prematurity are at an increased risk of morbidity and mortality. The long-term effects of apnea of prematurity or their treatments are less clear.

A LysR-type transcriptional regulator controls the expression of numerous small RNAs in Agrobacterium tumefaciens.

Small RNAs (sRNAs) are universal posttranscriptional regulators of gene expression and hundreds of sRNAs are frequently found in each and every bacterium. In order to coordinate cellular processes in response to ambient conditions, many sRNAs are differentially expressed. Here, we asked how these small regulators are regulated using Agrobacterium tumefaciens as a model system.

Arginine-Rich Small Proteins with a Domain of Unknown Function, DUF1127, Play a Role in Phosphate and Carbon Metabolism of Agrobacterium tumefaciens.

In any given organism, approximately one-third of all proteins have a yet-unknown function. A widely distributed domain of unknown function is DUF1127. Approximately 17,000 proteins with such an arginine-rich domain are found in 4,000 bacteria.

Remote monitoring of cardiac implanted electronic devices: legal requirements and ethical principles - ESC Regulatory Affairs Committee/EHRA joint task force report.

The European Union (EU) General Data Protection Regulation (GDPR) imposes legal responsibilities concerning the collection and processing of personal information from individuals who live in the EU. It has particular implications for the remote monitoring of cardiac implantable electronic devices (CIEDs). This report from a joint Task Force of the European Heart Rhythm Association and the Regulatory Affairs Committee of the European Society of Cardiology (ESC) recommends a common legal interpretation of the GDPR.

Optimization and quantification of the systematic effects of a rolling circle filter for spectral pre-processing.

Spectral pre-processing, especially baseline approximation, is a crucial part in quantitative spectroscopic applications, such as Raman or FTIR spectroscopy. Filters used for this task need to be optimized for their application, in order to achieve a sufficient baseline approximation while minimizing the distortion of the spectral lines. We propose a combined method that optimizes a rolling circle filter and quantifies the residual systematic influence on the spectral lines by a Monte Carlo approach that simulates and subsequently analyses spectra with known line properties and known maximum baseline curvature.

The RNase YbeY Is Vital for Ribosome Maturation, Stress Resistance, and Virulence of the Natural Genetic Engineer .

Riboregulation involving regulatory RNAs, RNA chaperones, and ribonucleases is fundamental for the rapid adaptation of gene expression to changing environmental conditions. The gene coding for the RNase YbeY belongs to the minimal prokaryotic genome set and has a profound impact on physiology in a wide range of bacteria. Here, we show that the gene is not essential.

Immunological and mass spectrometry-based approaches to determine thresholds of the mutagenic DNA adduct O-methylguanine in vivo.

N-nitroso compounds are alkylating agents, which are widespread in our diet and the environment. They induce DNA alkylation adducts such as O-methylguanine (O-MeG), which is repaired by O-methylguanine-DNA methyltransferase (MGMT). Persistent O-MeG lesions have detrimental biological consequences like mutagenicity and cytotoxicity.

PARP-1 protects against colorectal tumor induction, but promotes inflammation-driven colorectal tumor progression.

Colorectal cancer (CRC) is one of the most common tumor entities, which is causally linked to DNA repair defects and inflammatory bowel disease (IBD). Here, we studied the role of the DNA repair protein poly(ADP-ribose) polymerase-1 (PARP-1) in CRC. Tissue microarray analysis revealed PARP-1 overexpression in human CRC, correlating with disease progression.

One-pot syntheses of blue-luminescent 4-aryl-1-benzo[]isoindole-1,3(2)-diones by T3P activation of 3-arylpropiolic acids.

In situ activation of 3-arylpropiolic acids with T3P (-propylphosphonic acid anhydride) initiates a domino reaction furnishing 4-arylnaphtho[2,3-]furan-1,3-diones in excellent yields. Upon employing these anhydrides as reactive intermediates blue-luminescent 4-aryl-1-benzo[]isoindole-1,3(2)-diones are formed by consecutive pseudo three-component syntheses in a one-pot fashion. The Stokes shifts correlate excellently with the Hammett-Taft σ parameter indicating an extended degree of resonance stabilization in the vibrationally relaxed excited singlet state.

The Copper Efflux Regulator CueR Is Subject to ATP-Dependent Proteolysis in .

The trace element copper serves as cofactor for many enzymes but is toxic at elevated concentrations. In bacteria, the intracellular copper level is maintained by copper efflux systems including the Cue system controlled by the transcription factor CueR. CueR, a member of the MerR family, forms homodimers, and binds monovalent copper ions with high affinity.

DNA damage response curtails detrimental replication stress and chromosomal instability induced by the dietary carcinogen PhIP.

PhIP is an abundant heterocyclic aromatic amine (HCA) and important dietary carcinogen. Following metabolic activation, PhIP causes bulky DNA lesions at the C8-position of guanine. Although C8-PhIP-dG adducts are mutagenic, their interference with the DNA replication machinery and the elicited DNA damage response (DDR) have not yet been studied.

Highly Efficient and Scalable Separation of Semiconducting Carbon Nanotubes via Weak Field Centrifugation.

The identification of scalable processes that transfer random mixtures of single-walled carbon nanotubes (SWCNTs) into fractions featuring a high content of semiconducting species is crucial for future application of SWCNTs in high-performance electronics. Herein we demonstrate a highly efficient and simple separation method that relies on selective interactions between tailor-made amphiphilic polymers and semiconducting SWCNTs in the presence of low viscosity separation media. High purity individualized semiconducting SWCNTs or even self-organized semiconducting sheets are separated from an as-produced SWCNT dispersion via a single weak field centrifugation run.

DNA repair by MGMT, but not AAG, causes a threshold in alkylation-induced colorectal carcinogenesis.

Epidemiological studies indicate that N-nitroso compounds (NOC) are causally linked to colorectal cancer (CRC). NOC induce DNA alkylations, including O (6)-methylguanine (O (6)-MeG) and N-methylated purines, which are repaired by O (6)-MeG-DNA methyltransferase (MGMT) and N-alkyladenine-DNA glycosylase (AAG)-initiated base excision repair, respectively. In view of recent evidence of nonlinear mutagenicity for NOC-like compounds, the question arises as to the existence of threshold doses in CRC formation.

Lipoic acid inhibits the DNA repair protein O 6-methylguanine-DNA methyltransferase (MGMT) and triggers its depletion in colorectal cancer cells with concomitant autophagy induction.

Alkylating agents are present in food and tobacco smoke, but are also used in cancer chemotherapy, inducing the DNA lesion O (6)-methylguanine. This critical adduct is repaired by O (6)-methylguanine-DNA methyltransferase (MGMT), resulting in MGMT inactivation and degradation. In the present study, we analyzed the effects of the natural disulfide compound lipoic acid (LA) on MGMT in vitro and in colorectal cancer cells.

Nuclear ashes and outflow in the eruptive star Nova Vul 1670.

CK Vulpeculae was observed in outburst in 1670-1672 (ref. 1), but no counterpart was seen until 1982, when a bipolar nebula was found at its location. Historically, CK Vul has been considered to be a nova (Nova Vul 1670), but its similarity to 'red transients', which are more luminous than classical novae and thought to be the results of stellar collisions, has re-opened the question of CK Vul's status.

Two separate modules of the conserved regulatory RNA AbcR1 address multiple target mRNAs in and outside of the translation initiation region.

The small RNA AbcR1 regulates the expression of ABC transporters in the plant pathogen Agrobacterium tumefaciens, the plant symbiont Sinorhizobium meliloti, and the human pathogen Brucella abortus. A combination of proteomic and bioinformatic approaches suggested dozens of AbcR1 targets in A. tumefaciens.

Further investigations into the genotoxicity of 2,6-xylidine and one of its key metabolites.

The metabolite of several amide anaesthetics, 2,6-xylidine, is a possible human (Group 2B) carcinogen and induced nasal tumours in rats after dietary administration. However, published papers on the genotoxicity of 2,6-xylidine in vitro have given inconsistent results. It has been proposed that the genotoxicity of 2,6-xylidine is dependent on its metabolism to a key metabolite dimethylphenyl N-hydroxylamine (DMHA), which would then be further converted to form a reactive nitrenium ion by phase 2 (mainly acetylation) metabolism.