Spirulina is rich in protein hence it is used as single cell protein. The thallus organisation and methods of reproduction is given in Figure . . A prokaryote takes a joy ride on polar bear ( Aphanocapsa montana - a cynobacterium grow on the fur of polar bear).
Chroococcus Gloeocapsa Nostoc Spirulina Akinete (Anabaena) Fission (Synechocystis) Endospore (Dermacarpa) Figure . : Structure and reproduction in cyanophyceae . . Mycoplasma or Mollicutes The Mycoplasma are very small ( .
– .5µm), pleomorphic gram negative microorganisms. They are first isolated by Nocard and co- workers in the year from pleural fluid of cattle affected with bovine pleuropneumonia. They lack cell wall and appear like “Fried Egg” in culture. The DNA contains low Guanine and Cytosine content than true bacteria.
They cause disease in animals and plants. Little leaf of brinjal, witches broom of legumes phyllody of cloves, sandal spike are some plant diseases caused by mycoplasma. Pleuropneumonia is caused by Mycoplasma mycoides. The structure of Mycoplasma is given in Figure .
. Cell membrane Ribosome DNA Strand Figure . : Structure of Mycoplasma . .
Actinomycetes (Actinobacteria) Actinomycetes are also called ‘Ray fungi’ due to their mycelia like growth. They are anaerobic or facultative anaerobic microorganisms and are Gram positive. They do not produce an aerial mycelium. Their DNA contains high guanine and cytosine content (Example: Streptomyces ) .
Frankia is a symbiotic actinobacterium which produces root nodules and fixes nitrogen in non – leguminous plants such as Alnus and Casuarina . They produce multicellular sporangium. Actinomyces bovis grows in oral cavities and cause lumpy jaw. Streptomyces is a mycelial forming Actinobacteria which lives in soil, they impart “earthy odour” to soil after rain which is due to the presence of Geosmin (volatile organic compound).
Some important antibiotics namely, Streptomycin, Chloramphenicol, and Tetracycline are produced from this genus. . Fungi World War II and Penicillin History speaks on fungi Sir Alexander Fleming Discovery of Penicillin in the year is a serendipity in the world of medicine. The History of World War II recorded the use of Penicillin in the form of yellow powder to save lives of soldiers.