%0 Journal Article
%T Vital Autofluorescence: Application to the Study of Plant Living Cells
%A Victoria V. Roshchina
%J International Journal of Spectroscopy
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/124672
%X The application of various microscopy methods such as luminescence microscopy, microspectrofluorimetry and laser-scanning confocal microscopy has been considered as an approach to study the autofluorescence of plant living cells〞from cell diagnostics up to modelling the cell-cell contacts and cell interactions with fluorescent biologically active substances. It bases on the direct observations of secretions released from allelopathic and medicinal species and the cell-donor interactions with cell-acceptors as biosensors (unicellular plant generative and vegetative microspores). Special attention was paid to the interactions with pigmented and fluorescing components of the secretions released by the cells-donors from plant species. Colored components of secretions are considered as histochemical dyes for the analysis of cellular mechanisms at the cell-cell contacts and modelling of cell-cell interactions. The fluorescence of plant biosensors was also recommended for the testing of natural plant excretions as medical drugs. 1. Introduction The visible (400每700ˋnm) fluorescence of intact living cells (usually called autofluorescence) excited by ultraviolet, violet, or blue light is often observed under luminescence microscope [1, 2]. Due to special microspectrofluorimeters or confocal microscope the fluorescence spectra of objects studied and the emission intensity can be also measured. Autofluorescence is the natural emission of cellular components due to a contribution of fluorescent compounds located in different cellular compartments. In general blue and green emission reflects the participation of universal cellular fluorophores NAD(P)H (max. 460ˋnm), pterins (max. 450ˋnm), and flavins (max. 520ˋnm) [3], although in dry state weak blue fluorescence (420每450ˋnm) is also peculiar to isolated nucleotides, RNA, and DNA as well as some proteins, and seen in the films under luminescence microscope [4, 5], but water quenches the emission [4]. Besides, there are characteristic fluorescent compounds in various organisms [6]. In animal cells chitin (max. 450每460 and 520ˋnm), collagen and elastin (max. 400每430, 465, 495 and 520ˋnm) or cellulose (max. 420每430ˋnm) in plants, and fungi can also contribute in blue fluorescence [6]. Orange-red fluorescence depends on organism. In plant cells main known fluorophore used for environmental monitoring is chlorophyll with maximum 675每680ˋnm [7] and in photosynthesizing bacteria: bacteriochlorophyll [6]. Uroporphyrinogen and haemoglobin contribute in red lightening of mammalians, while green-red range emission may reflect
%U http://www.hindawi.com/journals/ijs/2012/124672/