Intermolecular Radical Reaction of <i>O</i>,<i>Se</i>-Acetals Generated via Seleno-Pummerer Rearrangement

A new general protocol for the synthesis of <i>O</i>,<i>Se</i>-acetals using the seleno-Pummerer reaction has been developed, and their radical-based two- and three-component coupling reactions were studied. The three-component coupling employed the <i>O</i>,<i>Se</i>-acetal, cyclopentenone, and an allylstannane derivative, and enabled stereoselective installations of α-acyloxy alkyl and functionalized allyl groups to generate the 2,3-<i>trans</i>-disubstituted cyclopentanone in a single operation. The obtained highly functionalized structure was used as an intermediate for facile assembly of the zedoarondiol carboskeleton

Electric Conductive Pattern Element Fabricated Using Commercial Inkjet Printer for Paper-Based Analytical Devices

Herein, we proposed the addition of an inkjet-printed conductive pattern to paper-based analytical devices (PADs) in order to expand their applications. An electric conductive pattern was easily, quickly, and inexpensively fabricated using a <i>commercial inkjet printer</i>. The addition of a printed electric element will enhance the applications of PADs without the loss of properties such as cost efficiency, disposability, and portability. In this study, we applied an inkjet-printed heater to a piece of paper and investigated its characteristics. The use of the heater as a valve, concentrator, and heat source for chemical reactions on PADs was investigated. Previously, these functions were difficult to realize with PADs. The inkjet-printed heater was used as a valve and concentrator through evaporation of the working fluid and solvent, and was also found to be useful for providing heat for chemical reactions. Thus, the combination of printed electric circuits and PADs has many potential applications

Wettability and Antifouling Behavior on the Surfaces of Superhydrophilic Polymer Brushes

The surface wettabilities of polymer brushes with hydrophobic and hydrophilic functional groups were discussed on the basis of conventional static and dynamic contact angle measurements of water and hexadecane in air and captive bubble measurements in water. Various types of high-density polymer brushes with nonionic and ionic functional groups were prepared on a silicon wafer by surface-initiated atom-transfer radical polymerization. The surface free energies of the brushes were estimated by Owens-Wendt equation using the contact angles of various probe liquids with different polarities. The decrease in the water contact angle corresponded to the polarity of fluoroalkyl, hydroxy, ethylene oxide, amino, carboxylic acid, ammonium salt, sulfonate, carboxybetaine, sulfobetaine, and phosphobetaine functional groups. The poly­(2-perfluorooctylethyl acrylate) brush had a low surface free energy of approximately 8.7 mN/m, but the polyelectrolyte brushes revealed much higher surface free energies of 70–74 mN/m, close to the value for water. Polyelectrolyte brushes repelled both air bubbles and hexadecane in water. Even when the silicone oil was spread on the polyelectrolyte brush surfaces in air, once they were immersed in water, the oil quickly rolled up and detached from the brush surface. The oil detachment behavior observed on the superhydrophilic polyelectrolyte brush in water was explained by the low adhesion force between the brush and the oil, which could contribute to its excellent antifouling and self-cleaning properties

Determination of Singlet Oxygen and Electron Transfer Mediated Mechanisms of Photosensitized Protein Damage by Phosphorus(V)porphyrins

The mechanism of photosensitized protein damage by phosphorus­(V) tetraphenylporphyrin derivatives (P­(V)­TPPs) was quantitatively clarified. P­(V)­TPPs bound to human serum albumin (HSA), a water-soluble protein, and damaged its tryptophan residue during photoirradiation. P­(V)­TPPs photosensitized singlet oxygen (¹O₂) generation, and the contribution of ¹O₂ to HSA damage was confirmed by the inhibitory effect of sodium azide, a ¹O₂ quencher. However, sodium azide could not completely inhibit HSA damage, suggesting the contribution of an electron transfer mechanism to HSA damage. The decrement in the fluorescence lifetime of P­(V)­TPPs by HSA supported the electron transfer mechanism. The contribution of these processes could be determined by the kinetic analysis of the effect of sodium azide on the photosensitized protein damage by P­(V)­TPPs

<i>psm-mec</i> RNA inhibits <i>agrA</i> translation.

<p>(<b>A</b>) Cell extracts of overnight cultures of Newman strain (WT) and the <i>agr-</i>null mutant (Δ<i>agr</i>) were electrophoresed in sodium dodecyl sulfate-polyacrylamide gels. One gel was stained with Coomassie Brilliant Blue (Left panel). Proteins in another gel were transferred to a membrane and used for Western blotting by anti-AgrA IgG (Right panel). (<b>B</b>) Cell extracts of 24 h-cultures of Newman strains transformed with empty vector (pND50), a plasmid carrying wild-type <i>psm-mec</i> (pF), a plasmid carrying <i>psm-mec</i> with a stop-codon (pC1), and a plasmid carrying <i>psm-mec</i> with the -7T>C promoter mutation (pM1) were subjected to Western blotting by anti-AgrA IgG. Each lane contains 3.5 µg proteins of cell extracts. (<b>C</b>) Cell extracts of 24 h-cultures of Newman, MW2 (USA400), and FRP3757 (USA300) strains that were transformed with pF carrying <i>psm-mec</i> (multi-copy), or integrated with <i>psm-mec</i> into the chromosome (single-copy) were subjected to Western blotting by anti-AgrA IgG (Upper panel). Each lane contains 3 µg proteins of cell extracts. Band intensities of AgrA were measured and are presented in the lower graph. The vertical axis represents the relative value against the AgrA band intensity of the parent strain in each Newman, MW2, and FRP3757 genetic background. Means ± standard deviations from four independent experiments are presented. Student t-test P-values between the parent strain and the <i>psm-mec</i>-introduced strain in each genetic background are presented. (<b>D</b>) The <i>agr</i> null mutant of Newman transformed with pMNS-agrBDCA carrying IPTG-inducible <i>agrBDCA</i> and pKE516 (empty vector), or pMNS-agrBDCA and pKE516-F carrying wild-type <i>psm-mec</i> was cultured in the presence or absence of IPTG. Cell extracts of 24-h cultures were subjected to Western blotting by anti-AgrA IgG. Each lane contains 6 µg proteins of cell extracts. (<b>E</b>) Schematic representation of <i>luc-</i>fusions of the <i>recF</i> promoter, <i>agrA</i> SD, the <i>agrA</i> ORF, and the <i>luc</i> ORF. Bold gray lines represent the plasmid construct. Horizontal dotted lines represent the regions deleted from the plasmids. Putative binding region means the region predicted to bind to the <i>psm-mec</i> RNA by <i>in silico</i> analysis. SD means Shine-Dalgarno sequence of <i>agrA</i>. (<b>F</b>) Luciferase activities of Newman strains that were transformed with the <i>luc-</i>fusion plasmids with <i>psm-mec</i> (+F) or without <i>psm-mec</i> (−F) were measured. The vertical axis represents the luciferase activity. Student t-test P-values between +F and −F are presented. NS, P>0.05. (<b>G</b>) Newman strain, which was integrated with <i>psm-mec</i> or without <i>psm-mec</i>, was transformed with the <i>luc-</i>fusion plasmids. Luciferase activities of the strains were measured. The vertical axis represents the relative luciferase activity of the <i>psm-mec</i>-integrated Newman [+F (single-copy)] against that of the Newman strain (−F). Student t-test P-values between +F and −F are presented. NS, P>0.05.</p

MRSA clinical isolates harboring a <i>psm-mec</i> mutation produce high amounts of PSMα3.

<p>Nucleotide sequences of <i>psm-mec</i> genes of 325 MRSA isolates were determined (<a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003269#ppat-1003269-t001" target="_blank"><b>Table 1</b></a>). MRSA strains harboring intact <i>psm-mec</i> (Intact), -7T>C-mutated <i>psm-mec</i> (-7T>C), or no <i>psm-mec</i> (Absence) were cultured for 15 h. The amounts of PSMα3 in the culture supernatants were measured. The vertical axis represents the relative amount of PSMα3 against that of Newman strain. Closed circles represent the amounts of PSMα3 of each MRSA strains, which are the means from two independent experiments. Magenta lines represent the averaged amount of PSMα3 of each MRSA groups. Cyan dotted line represents the amount of PSMα3 of CA-MRSA strain FRP3757 (USA300). Student t-test P-values are presented. ND, not detected.</p

Typing of SCC<i>mec</i> of MRSA clinical isolates.

<p><i>ccr</i> genes and <i>mec</i> gene complex were identified by multiplex PCRs <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003269#ppat.1003269-Kondo1" target="_blank">[48]</a>. All isolates were <i>mecA</i> positive. SCC<i>mec</i> types, I, II, and IV were assigned by the combination of types of <i>ccr</i> gene and <i>mec</i> gene complex. Abbreviations are as follows:</p>1<p>n.a., SCC<i>mec</i> type could not be assigned from the experiments;</p>2<p>Total, total number of isolates;</p>3<p>NT, non-typed, since DNA fragment was not amplified by PCR identifying either <i>ccr</i> genes or <i>mec</i> gene complex. ‘2+5’ in <i>ccr</i> type means that both type 2 and type 5 <i>ccr</i> were identified, indicating that 48 strains (25%) carry type II SCC<i>mec</i> and SCC carrying <i>ccrC</i>. ‘2+4’ in <i>ccr</i> type indicates that 2 strains (1%) carry type II or type VIII SCC<i>mec</i>. The combination of type 2 <i>ccr</i> and class C2 <i>mec</i> gene complex suggests that it might be a novel SCC<i>mec</i> element. Since it was out of scope of this paper, we classified it in the group of not assigned.</p

Identification of mutations of the <i>psm-mec</i> gene from MRSA strains.

<p>Mutation of <i>psm-mec</i> is presented as a number of nucleotides from the transcription start site of <i>psm-mec</i> and nucleotide substitutions. T>C means that thymine was exchanged with cytosine. Expression of the respective mutated <i>psm-mec</i> gene in the Newman strain was examined (<b><a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003269#ppat.1003269.s003" target="_blank">Fig. S3</a></b>) and is presented in the column ‘Expression’. 1, DNA fragment of 2206 bp (GenBank, AB 729111). 2, DNA fragment of 1332 bp (GenBank, AB 729110).</p

Typing of <i>spa</i> of MRSA clinical isolates.

<p><i>spa</i> types were identified by sequencing short-sequence repeats (SSRs) of <i>spa</i> gene <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003269#ppat.1003269-Shopsin1" target="_blank">[47]</a>. ‘New’ means new <i>spa</i> types that were identified in this study. These <i>spa</i> types were assigned as <i>spa</i> types 1491, 1492, 1493, and 1494.</p

Bacterial strains and plasmids used.

a<p>Amp, ampicillin; Cm, chloramphenicol; Tet, tetracycline; Phleo, phleomycin; Kan, kanamycin; Spc, spectinomycin.</p