Polysialic acids

Yoshida K., Rutishauser U., Crandall J. and Schwarting G. (1999). Polysialic acid facilitates migration of luteinizing hormone-releasing hormone neurons on vomeronasal axons. J Neurosci 19, 794-801. 

Lin, S. L., Inoue, Y., and Inoue S., Evaluation of high-performance anion-exchange chromatography with pulsed electrochemical and fluorometric detection for extensive application to the analysis of homologous series of oligo-and polysialic acids in bioactive molecules, Glycobiology, 9, 807, 1999. 

FIGURE 7-6 Neural cell adhesion molecule (NCAM) carries different levels of polysialic acid. (A) NCAM is depicted on a growing axon, without polysialic acid. Under these conditions, NCAM and LI molecules interact homophilically and axons fasciculate. (B) NCAM carries polysialic acid (PSA), and NCAM and LI molecules are far apart and cannot, therefore, interact. Growing axons do not fasciculate under these circumstances. 

Rutishauser, U. NCAM and its polysialic acid moiety a mechanism for pull/push regulation of cell interactions during development Dev. Suppl. 99-104,1992. 

Stummeyer, K., Dickmanns, A., Muhlenhoff, M., Gerardy-Schahn, R., and Ficner, R. (2005). Crystal structure of the polysialic acid-degrading endosialidase of bacteriophage K1F. Nat. Struct. Mol. Biol. 12, 90-96. 

Gluco-oligosaccharides, 3.341,342 Polysialic acids,Oligogalac-turonic acids3 3 ... 

C. Zuber, P. M. Lackie, W. A. Cattarall, and J. Roth, Polysialic acid is associated with sodium channels and the neural cell adhesion molecule N-CAN in adult rat brain, J. Biol. Chem. 267 9965 (1992). 

C. Sato, K. Kitajima, I. Tazawa, Y. Inoue, S. Inoue, and F. A. Troy, Structural diversity in the a-2—>8-linked polysialic acid chains in salmonid fish egg glycoproteins, J. Biol. Chem. 268 23675 (1993). 

PSA-NCAM, polysialic acid-neuronal cell adhesion molecule... 

Y. Inoue Diversity in sialic and polysialic acid residues and related enzymes... 

The neuA (ORF 25) and neuB (ORF 24) gene products were functionally characterized by complementation of E. coli K1 mutants EV5 and EV24 that are defective in K1 polysialic acid capsule biosynthesis. The EV5 mutant was complemented to wild-type capsule production by introduction of neuA, and the EV24 mutation complemented by the neuB gene. 

Jain and coworkers showed that polysialylation significantly changes the PK/PD profile of insulin, prolonging the hypoglycemic activity after subcutaneous (SC) administration to T/O mice. Slight differences were observed between derivatives obtained with 22 kDa and 39 kDa polysialic acid these were attributed to the slower hormone absorption obtained with the latter polymer, which favors hormone degradation at the injection site and hinders the interaction with the receptor more efficiently than the former polymer [11]. 

Polysialic acid (PSA) is a linear homopolymer of a2-8- or a2-9-linked sialic acid attached to protein scaffolds inclnding the neural cell adhesion molecule (NCAM). Two Golgi-resident polysialyltransferases, PST and STX, are responsible for its synthesis. Although PSA is widely distributed in embryonic tissues, it is normally found only in regenerating neural and muscle tissues in adults. Neo-expression of PSA is often associated with metastatic cancer (115). 

Samuel J, Bertozzi CR. Chemical tools for the study of polysialic acid. Trends Glycosci. Glycotech. 2004 16(91) 305-318. 

Kiss JZ, Wang C, Rougon G (1993) Nerwe-dependent expression of high polysialic acid neural cell adhesion molecule in neurohypophysial astrocytes of adult rats. Neurosci 53 213—221. 

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