FT-IR spectroscopical detection of some molecular structures in soil microorganisms

The absorption of light in infrared regions of the electromagnetic spectrum appears capable of delivering information on individual structural units of microbial cells, growth-dependent phenomena, storage materials, and endospores. We were able to make respective demonstrations by FT-IR spectroscopy different soil bacteria such as Azotobacter chroococcum, Bacillus subtilis, Pseudomonas spp. Usually, these bacteria delivered well distinguished IR spectra for structural units of nucleic acids, membrane fatty acids, saturated esters, cell proteins, glycopeptides, and phosphoesters, e.g. well differentiated spectra were obtained also from a natural population of soil microorganisms grown in a complex nutrient medium. The FT-IR spectroscopy proved a less laborious and time consuming method in determining different cell constituents, however, caution should be paid if there are differences in cultivation conditions, nutritional status and age of the bacteria under testing