Domain structure and cross-linking in a giant adhesin from the Mobiluncus mulieris bacterium.

Cell-surface proteins known as adhesins enable bacteria to colonize particular environments, and in Gram-positive bacteria often contain autocatalytically formed covalent intramolecular cross-links. While investigating the prevalence of such cross-links, a remarkable example was discovered in Mobiluncus mulieris, a pathogen associated with bacterial vaginosis. This organism encodes a putative adhesin of 7651 residues.

Effect of consecutive rare codons on the recombinant production of human proteins in Escherichia coli.

In Escherichia coli, the expression of heterologous genes for the production of recombinant proteins can be challenging due to the codon bias of different organisms. The rare codons AGG and AGA are among the rarest in E. coli.

Analysis of the extracellular vesicle proteome identifies markers of purity and culture conditions.

Bacteria release nano-sized extracellular vesicles (EVs) into the extracellular milieu. Bacterial EVs contain molecular cargo originating from the parent bacterium and have important roles in bacterial survival and pathogenesis. Using 8-plex iTRAQ approaches, we profiled the EV proteome of two strains, uropathogenic (UPEC) 536 and probiotic Nissle 1917.

Protein Levels and Microstructural Changes in Localized Regions of Early Cartilage Degeneration Compared with Adjacent Intact Cartilage.

Objective: It was hypothesized that the respective protein profiles of bovine cartilage from sites of localized mild to moderate (GI to GII) degeneration versus adjacent sites of intact tissue would vary in accordance with the tissue microstructural changes associated with a pre-osteoarthritic state.

Methods: A total of 15 bovine patellae were obtained for this study. Paired samples of tissue were collected from the lateral region of each patella.

Targeted Analysis of Phosphotyrosine Signaling by Multiple Reaction Monitoring Mass Spectrometry.

Phosphoproteomics is an important tool for the unbiased investigation of signaling network activation and has particular application to unraveling aberrant signaling driving cancer progression. However, validating the behavior of specific phosphosites across multiple experimental conditions remains challenging, due to limitations inherent in discovery-based proteomic workflows and the limited availability of high-quality antibodies required for alternative, immunoaffinity-based methods. Targeted phosphoproteomics enables specific phosphosites to be quantified reproducibly across multiple experimental conditions.

Dual Targeting of PDGFRα and FGFR1 Displays Synergistic Efficacy in Malignant Rhabdoid Tumors.

Subunits of the SWI/SNF chromatin remodeling complex are mutated in a significant proportion of human cancers. Malignant rhabdoid tumors (MRTs) are lethal pediatric cancers characterized by a deficiency in the SWI/SNF subunit SMARCB1. Here, we employ an integrated molecular profiling and chemical biology approach to demonstrate that the receptor tyrosine kinases (RTKs) PDGFRα and FGFR1 are coactivated in MRT cells and that dual blockade of these receptors has synergistic efficacy.

Alterations in the phosphoproteomic profile of cells expressing a non-functional form of the SHP2 phosphatase.

The phosphatase SHP-2 plays an essential role in growth factor signaling and mutations in its locus is the cause of congenital and acquired pathologies. Mutations of SHP-2 are known to affect the activation of the RAS pathway. Gain-of-function mutations cause the Noonan syndrome, the most common non-chromosomal congenital disorder.

Discoidin domain receptor 2 signaling networks and therapy in lung cancer.

Discoidin domain receptor 2 (DDR2) is an atypical receptor tyrosine kinase that binds to and is activated by collagen in the extracellular matrix. Recent exon sequencing studies have identified DDR2 to be mutated with a 3% to 4% incidence in squamous cell cancers of the lung. This article summarizes the current state of knowledge of DDR2 biology and signaling in lung squamous cell cancer.

Glycosylation at Asn211 regulates the activation state of the discoidin domain receptor 1 (DDR1).

Discoidin domain receptor 1 (DDR1) belongs to a unique family of receptor tyrosine kinases that signal in response to collagens. DDR1 undergoes autophosphorylation in response to collagen binding with a slow and sustained kinetics that is unique among members of the receptor tyrosine kinase family. DDR1 dimerization precedes receptor activation suggesting a structural inhibitory mechanism to prevent unwarranted phosphorylation.

The pathobiology of collagens in glioma.

Malignant gliomas are characterized by a diffuse infiltration into the surrounding brain parenchyma. Infiltrating glioma cells exist in close proximity with components of the tumor microenvironment, including the extracellular matrix (ECM). Whereas levels of collagens in the normal adult brain are low, in glioma, collagen levels are elevated and play a vital role in driving tumor progression.

Phosphoproteomics of collagen receptor networks reveals SHP-2 phosphorylation downstream of wild-type DDR2 and its lung cancer mutants.

Collagen is an important extracellular matrix component that directs many fundamental cellular processes including differentiation, proliferation and motility. The signalling networks driving these processes are propagated by collagen receptors such as the β1 integrins and the DDRs (discoidin domain receptors). To gain an insight into the molecular mechanisms of collagen receptor signalling, we have performed a quantitative analysis of the phosphorylation networks downstream of collagen activation of integrins and DDR2.

Mapping of the ATP-binding domain of human fructosamine 3-kinase-related protein by affinity labelling with 5'-[p-(fluorosulfonyl)benzoyl]adenosine.

The modification of proteins by reducing sugars through the process of non-enzymatic glycation is one of the principal mechanisms by which hyperglycaemia may precipitate the development of diabetic complications. Fn3K (fructosamine 3-kinase) and Fn3KRP (Fn3K-related protein) are two recently discovered enzymes that may play roles in metabolizing early glycation products. However, although the activity of these enzymes towards various glycated substrates has been established, very little is known about their structure-function relationships or their respective mechanisms of action.

Fructosamine-3-kinase-related-protein phosphorylates glucitolamines on the C-4 hydroxyl: novel substrate specificity of an enigmatic enzyme.

Fructosamine-3-kinase (FN3K) phosphorylates fructosamines to fructosamine-3-phosphates. Recent data from FN3K-knockout mouse indicate that this phosphorylation results in deglycation of proteins modified by non-enzymatic glycation process. A homolog of FN3K, the FN3K-related-protein (FN3KRP) displays 65% amino acid sequence identity with FN3K and is highly conserved in evolution.