Bacteria kingdom

Higher organisms were believed to be unable to withstand extreme environments most probably because of their cellular complexity and compartmentalization. Therefore research on extremophiles has focused mainly on organisms belonging to the Archaea and Bacteria kingdoms. However, a significant number of eukaryotes, both unicellular and multicellular, have evolved to live and thrive in extreme environments (e.g. Alvinella pompejana, Tetrahymena thermophila and Dunaliella salina). Hence, extremophiles span all three domains of life Archaea, Bacteria and Eukarya [61]. 

The potassium or calcium salt form of oxaUc acid is distributed widely ia the plant kingdom. Its name is derived from the Greek o>ys, meaning sharp or acidic, referring to the acidity common ia the foflage of certain plants (notably Oxalis and Mmex) from which it was first isolated. Other plants ia which oxahc acid is found are spinach, rhubarb, etc. Oxahc acid is a product of metabohsm of fungi or bacteria and also occurs ia human and animal urine the calcium salt is a principal constituent of kidney stones. 

Animals cannot synthesize vitamin A-active compounds and necessary quantities are obtained by ingestion of vitamin A or by consumption of appropriate provitamin A compounds such as P-carotene. Carotenoids are manufactured exclusively by plants and photosynthetic bacteria. Until the discovery of vitamin A in the purple bacterium Halobacterium halobium in the 1970s, vitamin A was thought to be confined to only the animal kingdom (56). Table 4 Hsts RDA and U.S. RDA for vitamin A (67). 

Life, in any form, without iron is in all likelihood impossible (see Summary and Conclusions). Iron compounds can be expected to be encountered in all species from anaerobic bacteria to man. Accordingly, a comprehensive survey of the naturally occurring iron compounds must necessitate examination of the three broad kingdoms of living species, viz., microorganisms (protists), plants and animals. 

Two original kingdoms first developed from the last universal common ancestor bacteria and archaea. 

Fig. 10.11 The modified tree of life still has the usual tree-like structure and also confirms that the eukaryotes originally took over mitochondria and chloroplasts from bacteria. It does, however, also show a network of links between the branches. The many interconnections indicate a frequent transfer of genes between unicellular organisms. The modified tree of life is not derived, as had previously been assumed, from a single cell (the hypothetical primeval cell ). Instead, the three main kingdoms are more likely to have developed from a community of primitive cells with different genomes (Doolittle, 2000)...

For most people, BL is represented by the flash of the firefly or the phosphorescence that frequently occurs on agitating the surface of ocean water. Chemical excitation, luminescent reactions occurs in almost all zoological kingdoms (bacteria, dinoflagelates, Crustacea, worms, clams, insects, and fishes) except higher vertebrates BL is not found in any organisms higher than fish. In most cases this phenomenon occurs within specialized cells called photocytes [3-5], As shown in Table 1, BL occurs in many terrestrial forms but is most common in the sea, particularly in the deep ocean, where the majority of species are luminescent [6],... 

Fungi are unicellular or multicellular organisms that are more highly evolved than bacteria (Chapter 17). They are members of the plant kingdom and include molds, mildew, smuts, rusts, and yeasts. They range in size from 3 to 50 fim. With the exception of yeasts, they are usually rod shaped and arranged end-to-end in strands or filaments. Yeasts are usually oval. 

Composting is a biological process mediated by microbes belonging to the kingdom Protest, which includes bacteria, algae, fungi, protozoa, and virus particles (Table 12.2). Microbes can be classified into metabolic types based on the carbon and energy sources utilized by the cell. Autotrophs use carbon dioxide as a... 

Chlorophylls occur very frequently in the plant kingdom, they are responsible for the colour of vegetables and some fruits. They also occur in algae and several bacteria. Chlorophylls in plants are photoreceptors and in photosynthesis the presence of a closed circuit of conjugated double bonds allows them to absorb light. Because of their predominant importance as photoreceptors a considerable number of analytical methods have been developed for the separation and quantitative determination. The analytical methods applied for the measurement of chlorophylls and carotenoids in food products have been reviewed previously [273],... 

Quinones are widespread in natnre (Thomson, 1971) and have a variety of functions in the life cycles of most kinds of living organisms. These diketones are fonnd in higher plants, fungi, bacteria, and throughout the animal kingdom, and they play a central role in many biosynthetic processes that involve electron transport, such as cellular respiration (nbiqninone) and photosynthesis (plastoqninone). Vitamin K is an important factor in blood... 

Purple acid phosphatase (PAP) or tartrate-resistant phosphatase is not thought to be a protein phosphatase but it has a very similar dimetallic active site structure to that found in protein phosphatases. PAPs have been identified in bacteria, plants, mammals, and fungi. The molecular weights (animal 35 kDa, plant 55 kDa) are different and they exhibit low sequence homology between kingdoms but the residues involved in coordination of the metal ions are invariant. " There has been considerable debate as to the identity of the metal ions in PAPs in vivo. Sweet potato, Ipomoea batatas, has been shown to possess two different PAP enzymes and the active site of one of them has been shown to contain one Fe and one Zn " " ion. Another report has established that the active site of a PAP from sweet potato contains one Fe " and one Mn +. The well-characterized red kidney bean enzyme and the soybean enzyme contain Fe " and Zn. Claims that PAP from sweet potato has 2Fe ions or 2Mn ions have been discussed elsewhere. One explanation is that these are different forms of the enzyme, another is that because the metal ions are labile and are rapidly incorporated into the active site, the enzyme contains a mixture of metal ions in vivo and the form isolated depends on the conditions of isolation. 

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