Probing the existence of non-thermal Terahertz radiation induced changes of the protein solution structure.

During the last decades discussions were taking place on the existence of global, non-thermal structural changes in biological macromolecules induced by Terahertz (THz) radiation. Despite numerous studies, a clear experimental proof of this effect for biological particles in solution is still missing. We developed a setup combining THz-irradiation with small angle X-ray scattering (SAXS), which is a sensitive method for detecting the expected structural changes.

A Case Study on the Customized Nutrition Intervention for a Patient with Primary Gastrointestinal Non-Hodgkin Lymphoma Underlying Chronic Kidney Disease.

Non-Hodgkin lymphoma comprises 2.1% of the total number of cancers in South Korea. Among those, diffuse large B cell lymphoma (DLBCL) comprises the largest percentage.

A versatile vector for mycobacterial protein production with a functional minimized acetamidase regulon.

Recombinant protein expression is a prerequisite for diverse investigations of proteins at the molecular level. For targets from Mycobacterium tuberculosis it is favorable to use M. smegmatis as an expression host, a species from the same genus.

WXG100 protein superfamily consists of three subfamilies and exhibits an α-helical C-terminal conserved residue pattern.

Members of the WXG100 protein superfamily form homo- or heterodimeric complexes. The most studied proteins among them are the secreted T-cell antigens CFP-10 (10 kDa culture filtrate protein, EsxB) and ESAT-6 (6 kDa early secreted antigen target, EsxA) from Mycobacterium tuberculosis. They are encoded on an operon within a gene cluster, named as ESX-1, that encodes for the Type VII secretion system (T7SS).

Parent-reported ISAAC written questionnaire may underestimate the prevalence of asthma in children aged 10-12 years.

Objectives: The aim of the present study was to compare the validity of the International Study of Asthma and Allergies in Childhood (ISAAC) written (WQ) and audiovisual questionnaires (AVQ 3.0) in two age-groups (10-12 and 13-15 years, respectively).

Methods: The 13-15 year olds performed the self-completed the WQ and AVQ on the same day.

Polymorphisms in GSDMA and GSDMB are associated with asthma susceptibility, atopy and BHR.

The gasdermin A (GSDMA) and gasdermin B (GSDMB) genes are located at 17q21.2. The GSDM family genes have been studied in the gastrointestinal tract but recent reports suggest that GSDMB is associated with childhood asthma in several populations.

Bronchiectasis in children: 10-year experience at a single institution.

Purpose: Bronchiectasis in children is still one of the most common causes of childhood mortality in developing countries. The aim of this study was to investigate the epidemiological characteristics, clinical features, underlying etiologic factors, and distinct change in the management of patients with bronchiectasis at Asan Medical Center Children's Hospital of Seoul.

Methods: A retrospective study of children diagnosed with bronchiectasis was conducted between January 1999 and December 2008.

Changes in the prevalence of childhood asthma in seoul from 1995 to 2008 and its risk factors.

Purpose: To investigate the prevalence of asthma and determine its risk factors in elementary school students in Seoul.

Methods: A modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was used to survey 4,731 elementary school students from five areas in Seoul between April and October, 2008.

Results: In elementary school children, the lifetime and recent 12-month prevalence of wheezing were 11.

Proteome-wide identification of mycobacterial pupylation targets.

Mycobacteria use a unique system for covalently modifying proteins based on the conjugation of a small protein, referred to as prokaryotic ubiquitin-like protein (PUP). In this study, we report a proteome-wide analysis of endogenous pupylation targets in the model organism Mycobacterium smegmatis. On affinity capture, a total of 243 candidate pupylation targets were identified by two complementary proteomics approaches.

The Effects of Lactobacillus rhamnosus on the Prevention of Asthma in a Murine Model.

Purpose: Lactobacilli are probiotic bacteria that are effective in the management of allergic diseases or gastroenteritis. It is hypothesized that such probiotics have immunoregulatory properties and promote mucosal tolerance. Our goal was to investigate whether Lactobacillus casei rhamnosus Lcr35 could inhibit airway inflammation in an ovalbumin (OVA)-induced murine model of asthma.

The peroxisomal receptor Pex19p forms a helical mPTS recognition domain.

The protein Pex19p functions as a receptor and chaperone of peroxisomal membrane proteins (PMPs). The crystal structure of the folded C-terminal part of the receptor reveals a globular domain that displays a bundle of three long helices in an antiparallel arrangement. Complementary functional experiments, using a range of truncated Pex19p constructs, show that the structured alpha-helical domain binds PMP-targeting signal (mPTS) sequences with about 10 muM affinity.

Molecular basis of the head-to-tail assembly of giant muscle proteins obscurin-like 1 and titin.

Large filament proteins in muscle sarcomeres comprise many immunoglobulin-like domains that provide a molecular platform for self-assembly and interactions with heterologous protein partners. We have unravelled the molecular basis for the head-to-tail interaction of the carboxyl terminus of titin and the amino-terminus of obscurin-like-1 by X-ray crystallography. The binary complex is formed by a parallel intermolecular beta-sheet that presents a novel immunoglobulin-like domain-mediated assembly mechanism in muscle filament proteins.

Difference in TB10.4 T-cell epitope recognition following immunization with recombinant TB10.4, BCG or infection with Mycobacterium tuberculosis.

Most novel vaccines against infectious diseases are based on recombinant Ag; however, only few studies have compared Ag-specific immune responses induced by natural infection with that induced by the same Ag in a recombinant form. Here, we studied the epitope recognition pattern of the tuberculosis vaccine Ag, TB10.4, in a recombinant form, or when expressed by the pathogen Mycobacterium tuberculosis (M.

Stoichiometric protein complex formation and over-expression using the prokaryotic native operon structure.

In prokaryotes, operon encoded proteins often form protein-protein complexes. Here, we show that the native structure of operons can be used to efficiently overexpress protein complexes. This study focuses on operons from mycobacteria and the use of Mycobacterium smegmatis as an expression host.

Structure-based prediction of the Saccharomyces cerevisiae SH3-ligand interactions.

A great challenge in the proteomics and structural genomics era is to discover protein structure and function, including the identification of biological partners. Experimental investigation is costly and time-consuming, making computational methods very attractive for predicting protein function. In this work, we used the existing structural information in the SH3 family to first extract all SH3 structural features important for binding and then used this information to select the right templates to homology model most of the Saccharomyces cerevisiae SH3 domains.

Bimolecular fluorescence complementation in structural biology.

Bimolecular fluorescence complementation is a method of probing protein-ligand interactions under physiological conditions. It provides a state-of-the-art tool to examine interactions observed in 3D structures of multi-component protein complexes, either to validate new experimental structures or to assess the correctness of homology models. Applications of the method range from homo- and hetero-oligomeric assemblies, including non-protein-ligands.

High-resolution structural analysis of mammalian profilin 2a complex formation with two physiological ligands: the formin homology 1 domain of mDia1 and the proline-rich domain of VASP.

Profilins are small proteins capable of binding actin, poly-l-proline and other proline-rich sequences, and phosphatidylinositol (4,5)-bisphosphate. A number of proline-rich ligands for profilin have been characterised, including proteins of the Ena/VASP and formin families. We have determined the high-resolution crystal structures of mouse profilin 2a in complex with peptides from two functionally important ligands from different families, VASP and mDia1.

Palindromic assembly of the giant muscle protein titin in the sarcomeric Z-disk.

The Z-disk of striated and cardiac muscle sarcomeres is one of the most densely packed cellular structures in eukaryotic cells. It provides the architectural framework for assembling and anchoring the largest known muscle filament systems by an extensive network of protein-protein interactions, requiring an extraordinary level of mechanical stability. Here we show, using X-ray crystallography, how the amino terminus of the longest filament component, the giant muscle protein titin, is assembled into an antiparallel (2:1) sandwich complex by the Z-disk ligand telethonin.

Human alpha-defensins neutralize anthrax lethal toxin and protect against its fatal consequences.

Anthrax caused by Bacillus anthracis represents a major bioterroristic threat. B. anthracis produces lethal toxin (LeTx), a combination of lethal factor (LF) and protective antigen that plays a major role in anthrax pathogenesis.

Age-dependent changes of gene expression in the Drosophila head.

Previous gene expression profiling studies in Drosophila have provided clues for understanding the aging process at the gene expression level. For a detailed understanding, studies of specific regions of the body are necessary. We therefore employed microarray analysis to examine gene expression changes in the Drosophila head during aging.

Downregulation of lipopolysaccharide response in Drosophila by negative crosstalk between the AP1 and NF-kappaB signaling modules.

IkappaB kinase (IKK) and Jun N-terminal kinase (Jnk) signaling modules are important in the synthesis of immune effector molecules during innate immune responses against lipopolysaccharide and peptidoglycan. However, the regulatory mechanisms required for specificity and termination of these immune responses are unclear. We show here that crosstalk occurred between the drosophila Jnk and IKK pathways, which led to downregulation of each other's activity.

MED16 and MED23 of Mediator are coactivators of lipopolysaccharide- and heat-shock-induced transcriptional activators.

Transcriptional activators interact with diverse proteins and recruit transcriptional machinery to the activated promoter. Recruitment of the Mediator complex by transcriptional activators is usually the key step in transcriptional activation. However, it is unclear how Mediator recognizes different types of activator proteins.

Nucleotide-induced conformations in the neck region of dimeric kinesin.

The neck region of kinesin constitutes a key component in the enzyme's walking mechanism. Here we applied cryoelectron microscopy and image reconstruction to investigate the location of the kinesin neck in dimeric and monomeric constructs complexed to microtubules. To this end we enhanced the visibility of this region by engineering an SH3 domain into the transition between neck linker and neck coiled coil.

Single-molecule investigation of the interference between kinesin, tau and MAP2c.

Motor proteins and microtubule-associated proteins (MAPs) play important roles in cellular transport, regulation of shape and polarity of cells. While motor proteins generate motility, MAPs are thought to stabilize the microtubule tracks. However, the proteins also interfere with each other, such that MAPs are able to inhibit transport of vesicles and organelles in cells.