Actinomycetes: Sources for Soil Enzymes

Abstract

The classification of the Prokaryotes is a complex issue. Their major subdivisions are the bacteria (Schizophyta), the blue green algae (Cyanophyta), and the Actinomycetales. The latter are sometimes called the “higher bacteria,” organisms possessing properties intermediate between the fungi and the bacteria. The Actinomycetes are gram-positive organisms that tend to grow slowly as branching elements. They are prokaryotes, sporulated, powdery growth organisms, and show similarity to fungi in the formation of branched aerial mycelium, which profusely sporulate. But these Actinomycetes differ from fungi in the composition of cell wall; they do not have chitin and cellulose that are commonly found in the cell wall of fungi. The number of Actinomycetes increases in the presence of decomposing organic matter. Depending on the abundance in the soil, the common genera of Actinomycetes are Streptomyces (70%), Nocardia, and Micromonospora although Actinomyces, Actinoplanes, and Streptosporangium have been encountered. The term Actinomycetes is used to indicate organisms belonging to the Actinomycetales, a major subdivision of the Prokaryotae, the kingdom that comprises all organisms with a prokaryotic cell. They were long regarded as fungi, as is reflected in their name: aktino (gr) ¼ ray, mykes (gr) ¼ mushroom (¼fungus).