Fluorescence Microscopic Spectroscopy for Investigation and Monitoring of Biological Diversity and Physiological State of Cyanobacterial Cultures

Abstract

In this chapter, a novel technique for investigation of natural and laboratory cyanobacterial cultures is presented. The technique is based on a strict relation between the intrinsic singlecell fluorescence emission spectra of cyanobacteria and the physiological state of the whole culture. It will be shown else that the single-cell fluorescence spectra for different species are steady enough to conduct a taxonomic analysis of cyanobacterial cultures based on a common statistical data evaluation among the parameters extracted from a set of such spectra. Several examples are given to illustrate the power and simplicity of a new technique, which can become a promising tool for automation of production in the cyanobacterial biotechnology, as well as give a valuable contribution to the development of innovative approaches in environmental monitoring of harmful algal blooms.

Protein arrangement factor: a new photosynthetic parameter characterizing the organization of thylakoid membrane proteins

“…Even though the heterogeneous arrangement of photosystems in plant thylakoids has been demonstrated (Andersson and Anderson 1980, Albertsson 2001, Ruban and Johnson 2015, their spatial distribution in cyanobacteria is still not fully resolved. Heterogeneity of PPCs in Synechocystis thylakoid membranes has been proposed to exist based on confocal microscopy studies (Casella et al 2017, Grigoryeva and Chistyakova 2018, Strašková et al 2019. Time-lapse confocal imaging of single cells suggested both dynamic (Sarcina et al 2006, Casella et al 2017 or rather static behavior of these heterogeneous structures in minutes time scale (Strašková et al 2019).…”

Confocal Laser Scanning Microscopy for Spectroscopic Studies of Living Photosynthetic Cells

“…If the fluorescence spectra were taken from alive cells in normal physiological state, which are cultured in the same growth environmental conditions, then the interspecies variations in pigment/Chl a ratios are more pronounced than variations within the individual species. And species/strains differentiation could be carried out on the base of fluorescence analysis [3,[6][7]. Figure 10 shows the experimental sets of single-cell fluorescence spectra for Microcystis CALU 398, Merismopedia CALU 666, Leptolyngbya CALU 1715, and Phormidium CALU 624 (cyanobacterial strains are labeled according to CALU collection of the Core Facility Center "Centre for Culture Collection of Microorganisms" of the Science Park of St. Petersburg State University).…”

“…Recent rapid development of confocal microscopes functionality initiates new directions in subcellular biology research. However, the experiments with photosynthetic cells require some additional specific skills and techniques to perform measurements and to carry out data processing [3][4][5][6][7]. The efficiency of photosynthesis and photosynthetic rate are highly dependent on irradiance.…”

“…Thus, special spectroscopic methods are required to study the physiology of phototrophic microorganisms [9]. These organisms employ light-dependent photosynthesis as the main energy source for their metabolism and the detected self-fluorescence finally reflects the diversity in morphological and physiological states of their photosynthetic cells [3][4][5][6][7].…”

“…The nondestructive spectroscopic analysis conducting in vivo at a sub-cellular level allows to obtain more complete information about special features of individual cyanobacterial cells and supports the registration of very weak variations in their physiological state. For example, a novel technique for discrimination of cyanobacterial species and physiological states of the cells belonging to one strain was elaborated by the authors of the present chapter [3][4][5]. The technique is based on a strict relation between physiological state and genera affiliation of cyanobacterial cells and the intensity and the shape of corresponding single-cell fluorescence spectra, obtained by means of confocal microscopic spectroscopy.…”