A Pathogenesis-Related Protein-Like Gene Is Involved in the Defense Response to the Root Rot Pathogen.

Pathogenesis-related proteins (PRs) are a class of proteins that accumulate in response to biotic and abiotic stresses to protect plants from damage. In this study, a gene encoding a PR-like protein (PnPR-like) was isolated from , which is used in traditional Chinese herbal medicines. An analysis of gene expression in indicated that was responsive to an infection by the root rot pathogen .

[Functional analysis of a chitinase gene PnCHI1 from Panax notoginseng].

Chitinases, a glycosidase enzyme that hydrolyzes chitin to N-acetylglucosamine, are widely found in plant cells, and they are an important part of plant antifungal defense system. The function of a Panax notoginseng chitinase gene PnCHI1 was characterized in this paper. Expression vector of PnCHI1 was constructed and transiently expressed in onion epidermal cells, and laser scanning confocal microscopy demonstrated that PnCHI1 was localized in the cell wall.

Vibrational excitations in chloromethyl radical formed by the photodissociation of chlorobromomethane.

Using velocity map ion imaging, the photodissociation of chlorobromomethane (CH2BrCl) at 233-234 nm has been studied. The total translational energy distributions and the anisotropy parameters have been determined from the ion images of the photofragments Br ((2)P1/2) (denoted as Br(*)) and Br ((2)P3/2) (denoted as Br) for the dominant CH2BrCl + hv → CH2Cl + Br(*) and CH2BrCl + hv → CH2Cl + Br channels. Using an impulsive model invoking angular momentum conservation, the vibrational energy distributions of the chloromethyl radicals have been derived from the total translational energy distributions for the two channels.

Photodissociation dynamics of 2-bromopropane using velocity map imaging technique.

Photodissociation dynamics of 2-bromopropane in the A band was investigated at several wavelengths between 232 and 267 nm using resonance-enhanced multiphoton ionization technique combined with velocity map ion-imaging detection. The ion images of Br ((2)P(3/2)) and Br* ((2)P(1/2)) were analyzed to yield corresponding total translational energy and angular distributions. The total translational energy distributions showed that the channel leading to Br carried more internal energy in the 2-C(3)H(7) moiety than the channel leading to Br*.

Probing ultrafast internal conversion of o-xylene via femtosecond time-resolved photoelectron imaging.

The dynamics of excited states in o-xylene molecules has been studied by femtosecond time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy. The ultrafast internal conversion from the S(2) state to the vibrationally hot S(1) state on timescale of 60 fs is observed on real time. The secondarily populated high vibronic S(1) state deactivates further to the S(0) state on timescale of 9.

One-color two-photon mass-analyzed threshold ionization spectroscopy of ethyl bromide through a dissociative intermediate state.

Mass-analyzed threshold ionization (MATI) spectra of ethyl bromide were obtained using one-color two-photon ionization through a dissociative intermediate state. Accurate values for the adiabatic ionization energy have been obtained, 83099+/-5 and 85454+/-5 cm(-1) for the X1 2E and X2 2E states of the ethyl bromide cation, respectively, giving a splitting of 2355+/-10 cm(-1). Compared with conventional photoelectron data, the two-photon MATI spectrum exhibited a more extensive vibrational structure with a higher resolution, mainly containing the modes involving the dissociation coordinate.