Protist

Sleigh, M.A. (1989). Protozoa and Other Protists. Edward Arnold, London. 

Robertson, H.M. (2004). Genes encoding vitamin K epoxide reductase are present in Drosophila and trypanosomatid protists. Genetics 168,1077-1080. 

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. 

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... 

Table 3. Amino acid composition of cytochrome c from some protist organisms...

Plants appear to contain few, if any, of the general types of iron compounds which are not represented elsewhere in the protist or animal kingdoms. 

Protists Animals, plants, fungi (cell differentiation) Multi-cell... 

Johnson, A.M. and Baverstock, B.P. (1989) Rapid ribosomal RNA sequencing and the phylogenetic analysis of protists. Parasitology Today 5, 102-105. 

Diehn, B. Photic responses and sensory transduction in motile protists, in Handbook of Sensory Physiology, (H. Autrum, ed.), pp. 24-68, Springer Berlin. 1979... 

The second myosin type identified in nervous tissue was the myosin I family. It was first described in protists and subsequently purified from brain. Myosin I is a singleheaded myosin with a short tail that uses calmodulin as a light chain [41]. In many cell types it has been implicated in both endocytosis and exocytosis, so it may play an important role in delivery and recycling of receptors. Myosin I is enriched in microvilli and may also be involved in some aspects of growth cone motility along with... 

T. Proeschold, B. Marin, UG. Schlosser, M. Melkonian (2001) Molecular phytogeny and taxonomic revision of Chlamydomonas (Chlorophyta). Protist, 152 265-300... 

Fungus A general term to denote a group of eukaryotic protist, including mushrooms, yeasts, rusts, molds, smuts, etc., which are characterized by the absence of a rigid cell wall composed of chitin, mannans, and sometimes cellulose. 

Vitamins, especially the water-soluble ones, provide the coenzymes for the most fundamental cellular reactions. Thus, their presence is required by vertebrates and invertebrates as well as by monocellular organisms, such as bacteria and other fungi and by protists. One finds in nature many microorganisms which need those vitamins that they are unable to produce at all or in sufficient quantities. Thus, one has a wide choice of... 

This form of luminescence occurs sporadically in a wide range of natural organisms, such as protists (bacteria, fungi), animals, marine invertebrates and fish. It even exists naturally, albeit rarely, in plants or in amphibians, reptiles, birds, or mammals. 

Strom S, Wolfe GV, Slajer A, Lambert S, Clough J (2003) Chemical defense in the microplankton. II Inhibition of protist feeding by P-dimethylsulfoniopropionate (DMSP). Limnol Oceanogr 48 230-237... 

Vertebrates contain several proteins that maintain the integrity of the blood plasma circulatory system. These contain domains that are specific to vertebrates (Gla, FN1, FN2) (Patthy, 1985), domains that are found in different contexts in invertebrates and/or protists (FBG, APPLE, KR) (Xu and Doolittle, 1990 Eschenbacher et al., 1993 Wilson et al., 1993) and a domain that is found in all cellular life (trypsin-like serine protease, Tryp SPc). The invertebrate versions of these domains, however, are found in molecular contexts that differ considerably from their vertebrate extracellular counterparts, indicating that although these nonenzy-... 

Protists Single-celled organisms more complex than bacteria that include protozoans and some types of algae. 

Table 1 Some naturally occurring simple cyclic dipeptides in the protist and plant kingdoms Diketopiperazine (all amino acids are in the L-configuration) Species...

DKPs are simple and easy to obtain and are quite common by-products of synthetic, spontaneous, and biological formation pathways. DKP formation has been well documented as side reactions of solid-phase and solution-phase peptide synthesis. In addition, DKPs have been shown to be decomposition products of various peptides, proteins, and other commercial pharmaceuticals. Cyclic dipeptides were found to be present in solutions of human growth hormone, bradykinin, histerlin, and solutions of agents within the classes of penicillins and cephalosporins. " DKPs are also enzymatically synthesized in several protists and in members of the plant kingdom. Hydrolysates of proteins and polypeptides often contain these compounds and they are commonly isolated from yeasts, lichens, and fungi. ... 

Anaerobic environments, such as swamps, marine and freshwater sediments, and the body cavities of animals, are teeming with large numbers of single-ceUed eukaryotes (protists) that, like all cells, must produce ATP to survive. Some of these protists, such as ciUates, trichomonads, and chytrid... 

Bradley PJ, Lahti CJ, Plumper E, Johnsons PJ. 1997. Targeting and translocation of proteins into the hydrogenosome of the protist Trichomonas similarities with mitochondrial protein import. EMBO J 16 3484-93. 

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