Prokaryotic microorganisms

The catechol-type ligand appears to be restricted to siderochromes derived from prokaryotic microorganisms. Klebsiella oxytoca, an organism closely related to members of the genus Aerobacter, forms the 2,3-dihy-droxy-N-benzoyl derivates of serine and threonine in three day cultures (72). It is not known if the latter amino acid occurs in trimers but examination of space-filling CPK models does indicate that enterobactin could accomodate a methyl substituent on the carbon of the serine residue. Catechols occur in higher protist organisms but their formation... 

Bacteria Unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three prindpal forms round or coccal, rodlike or badllary, and spiral or spirochetal. [NIH]... 

Like all bacteria, actinomycetes are prokaryotic microorganisms. In addition, the adenine-thymine and guanine-cytosine contents of bacteria and actinomycetes are similar, as are the cell wall constituents of both types of microorganisms. Actinomycetes filaments are also about the same size as those of bacteria. 

The ansamycins are a remarkable group of natural compounds varying widely in both their chemical structure and their biological activities. They have mostly been isolated from prokaryotic microorganisms, but one group, the maytansines, occurs in plants. 

The enzyme nitrogenase is found in both symbiotic and free-living prokaryotic microorganisms that grow either aerobically or anaerobically. Reduction of nitrogen by the... 

McElhaney RN. Membrane lipid fluidity, phase state and membrane function in prokaryotic microorganisms. In Membrane Fluidity in Biology, Volume 4. Aloia RA, Boggs JM, eds. 1985. Academic Press, New York. pp. 147-208. 

In addition to ferrous iron, ferric iron can be very abundant in acid drainage solutions, especially where the activity of ferrous iron-oxidizing prokaryotic microorganisms is high (see below for details). In fact, the observed iron speciation may be largely determined by the balance between microbial ferrous iron oxidation rates and the rates at which ferric iron is reduced by oxidation of sulfide, sulfur, and sulfoxy species. 

Prokaryotic microorganisms that are distinct from fungi, which are eukaryotic. Prokaryotic organisms lack a true nucleus. Their DNA is present within the cytoplasm. Bacteria are usually unicellular and have a rigid cell wall. Cell division usually occurs by binary fission. 

Poly(3-hydroxybutyrate) and a few other PHAs were in prokaryotic microorganisms and in eukaryotic micro-organisms as well as in higher organisms also found in complexes and/or associated with other molecules in the laboratory of Reusch [10]. In these cases PHAs do not occur as insoluble inclusions, have a much lower MW, and they contribute only marginally (about 0.2% of the cell dry... 

Besides B. sulfurescens 1-49 89 90-93, yeast44"94-97 and various fungi48 Clostridia and Actinomycetes were also able to reduce 2-cyclohexenone or 2-methyl-2-cyclohexenonc in high yield98. Thus, the ability to reduce the double bond in this type of substrate seems to be widespread among eukaryotic and prokaryotic microorganisms. 

Both, eukaryotic and prokaryotic microorganisms are able to produce )S-lactam antibiotics (Fig. 5.21).They may be divided into five classes corresponding to their core structures (Tab. 5.2). [26] Tab. 5.3 lists some of the most important intermediates and active compounds from the penicillin and cephalosporin... 

The controlling action of cell autoregulators is thought to be seen in the most clear form in the primitive prokaryotic microorganisms. The actinomyoetes seem to be especially convenient subjects for such investigations, because these typical prokaryotes are characterized simultaneously by pronounced processes of differentiation and by unusually rich biosynthetic possibilities. Numerous actinomyoetes have great practical use as producers of antibiotics peculiar in their structure. 

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