Sensitive and specific detection of Xanthomonas campestris pv campestris by PCR using species-specific primers based on hrpF gene sequences.

A sensitive and specific assay was developed to detect bacterial black rot of crucifers caused by Xanthomonas campestris pv. campestris (X. c.

Colorimetric reversibility of polydiacetylene supramolecules having enhanced hydrogen-bonding under thermal and pH stimuli.

To investigate the role of hydrogen-bonding on colorimetric transition of polydiacetylene supramolecules, novel diacetylene derivatives allowing various hydrogen-bonding states were synthesized by coupling carboxy-substituted (ortho-, meta-, and para-) anilide groups with a typical single-chain diacetylene lipid. One with a terminal carboxyl group at the meta position provided the resulting supramolecular Langmuir-Schaefer films with enhanced hydrogen-bonding, and hence resulted in unprecedented colorimetric reversibility under both thermal and pH stimuli.

A comprehensive model for predicting burnout in Korean nurses.

Background: Although burnout among nurses has been studied in a great deal, this work has not included Korean nurses. Furthermore, the role of personal resources such as empathy and empowerment in predicting the variance in burnout has never been examined.

Aim: The purpose of this study was to understand the phenomenon of burnout among Korean nurses.

Dissociation of multiple protein ion charge states following a single gas-phase purification and concentration procedure.

The formation of a range of precursor ion charge states from a single concentrated and purified charge state, followed by activation of each charge state, is introduced as a means to obtain more protein structural information than is available from dissociation of a single charge state alone. This approach is illustrated using off-resonance collisional activation of the [M + 8H]8+ to [M + 6H]6+ precursor ions of the bacteriophage MS2 viral coat protein following concentration and purification of the [M + 8H]8+ charge state. This range of charge states was selected on the basis of an ion trap collisional activation study of the effects of precursor ion charge state on the dissociation of the [M + 12H]12+ to [M + 5H]5+ ions.

Liquid chromatographic resolution of N-acyl-alpha-amino acids as their anilide derivatives on a chiral stationary phase based on (S)-leucine.

A chiral stationary phase (CSP 1) derived from N-(3,5-dinitrobenzoyl)leucine N-phenyl N-alkylamide was used for the liquid chromatographic resolution of anilide derivatives of N-acyl-alpha-amino acids and the chromatographic resolution results were compared with those from four other commercial CSPs. The chromatographic resolution results showed that CSP 1 was most effective among five CSPs used in this study. The chiral recognition mechanism exerted by CSP 1 for the resolution of anilide derivatives of N-acyl-alpha-amino acids is proposed to involve a face-to-face pi-pi interaction and two hydrogen bonding interactions between the CSP and the analytes from the chromatographic resolution behaviors of slightly modified anilide derivatives of N-acyl-alpha-amino acids.

Gas-phase concentration, purification, and identification of whole proteins from complex mixtures.

Five proteins present in a relatively complex mixture derived from a whole cell lysate fraction of E. coli have been concentrated, purified, and dissociated in the gas phase, using a quadrupole ion trap mass spectrometer. Concentration of intact protein ions was effected using gas-phase ion/ion proton-transfer reactions in conjunction with mass-to-charge dependent ion "parking" to accumulate protein ions initially dispersed over a range of charge states into a single lower charge state.