Mussel adhesive Protein-conjugated Vitronectin (fp-151-VT) Induces Anti-inflammatory Activity on LPS-stimulated Macrophages and UVB-irradiated Keratinocytes

BACKGROUND

Skin inflammation and dermal injuries are a major clinical problem because current therapies are limited to treating established scars, and there is a poor understanding of healing mechanisms. Mussel adhesive proteins (MAPs) have great potential in many tissue engineering and biomedical applications. It has been successfully demonstrated that the redesigned hybrid type MAP (fp-151) can be utilized as a promising adhesive biomaterial. The aim of this study was to develop a novel recombinant protein using fp-151 and vitronectin (VT) and to elucidate the anti-inflammatory effects of this recombinant protein on macrophages and keratinocytes.

METHODS

Lipopolysaccharide (LPS) was used to stimulate macrophages and UVB was used to stimulate keratinocytes. Inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 were analyzed by Western Blot. Inflammatory cytokines and NO and ROS production were analyzed.

RESULT

In macrophages stimulated by LPS, expression of the inflammatory factors iNOS, COX-2, and NO production increased, while the r-fp-151-VT-treated groups had suppressed expression of iNOS, COX-2, and NO production in a dose-dependent manner. In addition, keratinocytes stimulated by UVB and treated with r-fp-151-VT had reduced expression of iNOS and COX-2. Interestingly, in UVB-irradiated keratinocytes, inflammatory cytokines, such as interleukin (IL)-1b, IL-6, and tumor necrosis factor (TNF)-a, were significantly reduced by r-fp-151-VT treatment.

CONCLUSIONS

These results suggest that the anti-inflammatory activity of r-fp-151-VT was more effective in keratinocytes, suggesting that it can be used as a therapeutic agent to treat skin inflammation.

Effect of glutathione on growth of the probiotic bacterium Lactobacillus reuteri

Glutathione (GSH) is an abundant nonprotein thiol that plays numerous roles within the cell. Previously, we showed that Lactobacillus salivarius has the capacity to mount a glutathione-mediated acid-tolerance response. In the present work we provide evidence of a requirement for GSH by Lactobacillus reuteri and have studied the role of GSH during cell growth. Medium supplementation with 0.5 mM GSH as the sole sulfur source enhanced cell growth, resulting in an increase in glucose consumption, and increased cell GSH and protein contents compared with levels seen in the absence of supplementation. Moreover, L. reuteri showed enhanced amino acid consumption when grown with 0.5 mM GSH. These findings indicate that glutathione is a nutrient for bacterial growth.

Intra-system optical interconnection module directly integrated on a polymeric optical waveguide

A new intra-system optical interconnection module directly integrated on a polymeric optical waveguide is suggested. A polymeric optical waveguide plays a role in the propagation path of optical signals from the transmitter to the receiver and in a platform integrated with various optical/electrical devices such as a vertical cavity surface emitting laser, photodiode, very large scale integrated circuit chips, and electrical connectors. Because the polymeric optical waveguide is simultaneously used as an integrated platform, the fabrication process of the optical interconnection module is very simple, and the proposed process is compatible with the conventional printed circuit board process. The suggested optical interconnection was also successfully demonstrated with a 5-Gb/s data transmission through the module directly integrated on a polymeric optical waveguide.

Chip- and board-level optical interconnections using rigid flexible optical electrical printed circuit boards

A new optical interconnection scheme based on a rigid flexible optical electrical printed circuit board (RFOE-PCB) is suggested. The easily installed RFOE-PCB can be universally applied for both chip- and board-level optical interconnections. This letter describes the detailed fabrication process, optical properties, and heat-resisting property of the RFOE-PCB. The fabricated RFOE-PCB was also successfully demonstrated with a 2.5-Gb/s data transmission through a 45 degrees-ended optical waveguide embedded in the RFOE-PCB.

Functional and structural characterization of a thiol peroxidase from Mycobacterium tuberculosis

A thiol peroxidase (Tpx) from Mycobacterium tuberculosis was functionally analyzed. The enzyme shows NADPH-linked peroxidase activity using a thioredoxin-thioredoxin reductase system as electron donor, and anti-oxidant activity in a thiol-dependent metal-catalyzed oxidation system. It reduces H2O2, t-butyl hydroperoxide, and cumene hydroperoxide, and is inhibited by sulfhydryl reagents. Mutational studies revealed that the peroxidatic (Cys60) and resolving (Cys93) cysteine residues are critical amino acids for catalytic activity. The X-ray structure determined to a resolution of 1.75 A shows a thioredoxin fold similar to that of other peroxiredoxin family members. Superposition with structural homologues in oxidized and reduced forms indicates that the M. tuberculosis Tpx is a member of the atypical two-Cys peroxiredoxin family. In addition, the short distance that separates the Calpha atoms of Cys60 and Cys93 and the location of these cysteine residues in unstructured regions may indicate that the M. tuberculosis enzyme is oxidized, though the side-chain of Cys60 is poorly visible. It is solely in the reduced Streptococcus pneumoniae Tpx structure that both residues are part of two distinct helical segments. The M. tuberculosis Tpx is dimeric both in solution and in the crystal structure. Amino acid residues from both monomers delineate the active site pocket.

Crystal structure of a putative pyridoxine 5′-phosphate oxidase (Rv2607) from Mycobacterium tuberculosis

The three-dimensional structure of Rv2607, a putative pyridoxine 5'-phosphate oxidase (PNPOx) from Mycobacterium tuberculosis, has been determined by X-ray crystallography to 2.5 A resolution. Rv2607 has a core domain similar to known PNPOx structures with a flavin mononucleotide (FMN) cofactor. Electron density for two FMN at the dimer interface is weak despite the bright yellow color of the protein solution and crystal. The shape and size of the putative binding pocket is markedly different from that of members of the PNPOx family, which may indicate some significant changes in the FMN binding mode of this protein relative to members of the family.

Engineering soluble proteins for structural genomics

Structural genomics has the ambitious goal of delivering three-dimensional structural information on a genome-wide scale. Yet only a small fraction of natural proteins are suitable for structure determination because of bottlenecks such as poor expression, aggregation, and misfolding of proteins, and difficulties in solubilization and crystallization. We propose to overcome these bottlenecks by producing soluble, highly expressed proteins that are derived from and closely related to their natural homologs. Here we demonstrate the utility of this approach by using a green fluorescent protein (GFP) folding reporter assay to evolve an enzymatically active, soluble variant of a hyperthermophilic protein that is normally insoluble when expressed in Escherichia coli, and determining its structure by X-ray crystallography. Analysis of the structure provides insight into the substrate specificity of the enzyme and the improved solubility of the variant.