Collagen invertebrate

Zinc normally aids wound healing in terrestrial invertebrates. Wounding of the optic tentacle, foot tissue, and partial shell removal in Helix aspersa, a terrestrial gastropod, resulted in deposition of zinc in the wound area after 2 to 5 days. Increased zinc in Helix wound areas may be necessary to promote protein synthesis, collagen formation, and mitotic cell division (Ireland 1986). 

The amount of collagen varies from one species to another and from tissue to tissue within the same species. Collagen comprises as much as one third of the total protein in the vertebrate body and in certain invertebrates, such as sponges and echinoderms as well as corals186, collagen may account for an even larger proportion of the total protein of the organism. 

Collagens are found in all metazoan organisms.652 Invertebrate collagens play a variety of specialized roles.653 For example, minicollagens from Hydra strengthen the walls of their nematocysts.572... 

The cuticles of invertebrates. The tough elastic cuticle of the nematode Caenorhabditis is largely collagen. However, the molecules are smaller than in... 

In contrast to calcareous invertebrates with their species specific shell organic matrix213-221 apatite depositors follow a rather conservative pattern set by collagen for bone, scale, and dentin deposition, or by a keratin-type protein in the case of enamel formation412. Nevertheless, a certain spread in the concentration of amino acids can be recognized if one, for instance, compares dentin of species en-... 

In invertebrates, collagen is uncalcified, whereas in vertebrates it occurs in the form of soft and hard tissue. Remains of the earliest vertebrates — bony armour — are found in sediments of the Ordovician (ca. 500 million years). At about that time, conodonts appeared in the stratigraphic column mineralogically they are carbonate apatite. Conodonts are small tooth-shaped fossils 0.2 to 3 mm in size whose origin is in doubt they are most likely remains of some unknown chordata that became extinct in Triassic time516. ... 

In recent years the use of ion-exchange chromatography has greatly improved the accuracy and speed of amino acid analysis, and in the case of collagen and gelatin has provided us with complete compositions from nearly every class of vertebrates. A number of invertebrate collagens have also been analyzed. 

Amino Acid Composition of Invertebrate Collagens and Gelatins ... 

All of the invertebrate collagens which have been examined have yielded the typical collagen wide-angle X-ray diffraction pattern, and electron micrographs of the fibers show, with the exception of Physalia float and Metridium body wall, the characteristic 600-700 A axial period (Gross et al., 1958). 

Bairati A. and Garrone R. (eds.) (1985) Biology of Invertebrate and Lower Vertebrate Collagens. NATO Advanced Research Workshop on the Biology of Invertebrate and Vertebrate Collagens (1984). Plenum, New York. 

In most proteins the proportion of each of the different a.a. residues, calculated as a percent of the total number of residues, ranges from 0 to about 30%. In extreme cases it may even reach 50%. Cereal proteins are generally very poor in Lys. Several major grains are deficient in Thr, Leu, Met, Val, and Trp. In most collagens there are no Cys and Trp residues, while the content of Gly, Pro, and Ala is 328, 118, and 104 residues/1000 residues, respectively. Paramyosin, abundant in the muscles of marine invertebrates, is rich in Glu (20-24%), Asp (12%), Arg (12%), and Lys (9%). The antifreeze fish serum glycoproteins contain several a.a. sequences of Thr-X2-Y-X7, where X is predominantly Ala and Y a polar residue. The antifreeze proteins of type I usually contain more than 60 mol% of Ala. Thr and Y, and in various antifreeze... 

The glycosyltransferase which glycosylates the hydroxyl group of 5-hydroxylysine in collagens and similar proteins appears to recognize the amino acid sequence -G1 y-X—HyZ-Gly-Y-Arg- Whereas the amino acids X and Y are quite variable, the positions of Gly, Hyl, and Arg are invariant in the glycopeptides of ten vertebrate and invertebrate collagens (169). 

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