The global response regulator GacA of Pseudomonas aeruginosa PAO1 positively controls the production of the quorum sensing signal molecule N-butanoyl-homoserine-lactone (C4-HSL) and hence the synthesis of several C4-HSL-dependent virulence factors, including hydrogen cyanide (HCN). This study presents evidence that GacA positively influences the transcription of the rhlI gene, specifying C4-HSL...

We present a sensitive 3 upper limit of 1.1% for the HNC/HCN abundance ratio in comet 73P/SchwassmannWachmann (fragment B), obtained on 2006May 10Y11, using Caltech Submillimeter Observatory (CSO). This limit is a factor of 7 lower than the values measured previously in moderately active comets at 1 AU from the Sun. Comet 73P/Schwassmann-Wachmann was depleted in most volatile species, except of...

There is increasing interest in using the cyanogenic properties of Pseudomonas aeruginosa to develop a nonmicrobiological method for its detection. Prior to this, the variation in cyanide production between different P. aeruginosa strains needs to be investigated. Hydrogen cyanide (HCN) released into the gas phase by 96 genotyped P. aeruginosa samples was measured using selected ion flow tube-m...

Disruption of ionic homeostasis and neuronal hyperexcitability contribute to early brain injury after subarachnoid hemorrhage (SAH). The hyperpolarization-activated/cyclic nucleotide (HCN)-gated channels play critical role in the regulation of neuronal excitability in hippocampus CA1 region and neocortex, in which the abnormal neuronal activities are more readily provoked. This study was to inv...

Pseudomonas aureofaciens PGS12 produces three phenazine antibiotics, in addition to siderophores, hydrogen cyanide, pyrrolnitrin, and indoleacetic acid. Tn5-259.7 transposon mutagenesis was carried out to identify and clone a chromosomal locus involved in phenazine biosynthesis. Three classes of mutants were obtained: mutants deficient in phenazine production (Phz-), mutants deficient in hydrog...

We observed a sample of southern S stars with the SEST telescope, in the SiO (v=0, J=3-2) transition at 130.3 GHz, and the HCN (J=1-0) transition at 88.6 GHz. SiO emission was detected in all seven stars observed, while HCN was detected in two. We employed a statistical equilibrium/radiative transfer model to estimate the SiO abundance for an assumed molecular distribution. The inferred SiO abu...

Aims. Following the first detection of hydrogen isocyanide (HNC) in Titan’s atmosphere, we have devised a new neutral chemical scheme for hydrogen cyanide (HCN) and HNC in the upper atmosphere of Titan. Methods. Our updated chemical scheme contains 137 compounds (with C, H, O and N elements) and 788 reactions (including 91 photolysis processes). To improve the chemistry of HNC and HCN, a carefu...

The physiological dormancy of sunflower (Helianthus annuus) embryos can be overcome during dry storage (after-ripening) or by applying exogenous ethylene or hydrogen cyanide (HCN) during imbibition. The aim of this work was to provide a comprehensive model, based on oxidative signaling by reactive oxygen species (ROS), for explaining the cellular mode of action of HCN in dormancy alleviation. B...

The physiological dormancy of sunflower (Helianthus annuus) embryos can be overcome during dry storage (after-ripening) or by applying exogenous ethylene or hydrogen cyanide (HCN) during imbibition. The aim of this work was to provide a comprehensive model, based on oxidative signaling by reactive oxygen species (ROS), for explaining the cellular mode of action of HCN in dormancy alleviation. B...

Alteration in hydrocyanic acid potential (HCN-p) of the forage is one of the important objectives in sudangrass [Sorghum sudanense (Piper) Stapf] breeding programs. The effectiveness of recurrent phenotypic selection for increasing or decreasing HCN-p in sudangrass was evaluated in two cycles of individual plant selection in the cultivar 'Greenleaf. In cycle 1, HCNp means of the high and low po...