HETEROCYST - Cyanobacteria - page 255

Tiwari, 1970; Singh et al ., 1972). Wilcox et al . (1973a,b) suggested that regression of proheterocysts
into vegetative cells could be possible only up to stage V in differentiation process.
ii) Storage cells : The heterocysts have been considered as storage organs for a number of enzymes
(Canabaeus, 1929), cyanophycin and growth-promoting substances (Fritsch, 1940).
iii) Attachment organs : Species of Anabaena , Rivularia , Gloeotrichia and Scytonema growing on
terrestrial substrata produce hormogones and with the help of terminal or intercalary heterocysts
they get attached to the substratum and develop.
iv) Role in akinete formation : In traditional taxonomic literature, distinction of species of Gloeotrichia
and Cylindrospermum is generally made on the morphology of akinetes. Because of the differentiation
akinetes just adjacent to the heterocysts in A . cylindrica , Wolk (1965) fi rst advocated that heterocysts
play a role in akinete formation. The intiation of akinetes midway between two heterocysts and
progressive maturation towards heterocyst has also been noted in some species of Anabaena and
Nostoc . This aspect has been disciussed in the Chapter 3.
LITERATURE CITED
Aboulmagd, E., Oppermann-Sanio, F. B., and Steinbüchel, A. (2000) Molecular characterization of the cyanophycin synthetase
from Synechocystis sp. strain PCC 6803. Arch Microbiol 174: 297-306.
Aboulmagd, E., Oppermann-Sanio, F. B., and Steinbüchel, A. (2001) Purifi cation of Synechocystis sp. strain PCC 6803
cyanophycin synthetase and its characterization with respect to substrate and primer specifi city. Appl Environ Microbiol
67: 2176-2182. Doi:10.1128/AEM.6752176-2182.2001
Abreu-Grobois, F. A., Billyard, T. C., and Walton, T. J. (1977) Biosynthesis of heterocyst glycolipids of Anabaena cylindrica .
Phytochemistry 16: 351-354.
Adams, D. G. (1992) The effect of 7-azatryptophan on heterocyst development in the cyanobacterium Anabaena cylindrica . J
Gen Microbiol 138: 335-362.
Adams, D. G. (2000) Heterocyst formation in cyanobacteria. Curr Opin Microbiol 3: 618-624.
Adams, D. G., and Carr, N. G. (1981) Heterocyst differentiation and cell division in the cyanobacterium Anabaena cylindrica .
Effect of high light intensity. J Cell Sci 49: 341-352.
Adams, D. G., and Carr, N. G. (1989) Control of heterocyst development in the cyanobacterium Anabaena cylindrica . J Gen
Microbiol 135: 839-849.
Adams, D. G., and Duggan, P. S. (1999) Heterocyst and akinete differentiation in cyanobacteria. Tansley Review No. 107.
New Phytol 144: 3-33.
Agervald, Å., Stensjö, K., Holmqvist, M., and Lindblad, P. (2008) Transcription of the extended hyp -operon in Nostoc PCC
7120. BMC Microbiol 8: 69. doi:10.1186/1471-2180-8-69
Agrawal, M., and Kumar, H. D. (1978) Effect of 7-azatryptophan on heterocyst differentiation in Anabaena doliolum Bharadwaja.
Proc Indian Acad Sci 87: 31-39.
Aldea, M. R., Mella-Herrera, R. A., and Golden, J. W. (2007) Sigma factor genes sigC, sigE and sigG are upregulated in
heterocysts of the cyanobacterium Anabaena sp. strain PCC 7120. J Bacteriol 189: 8392-8396.
Aldehni, M. F., and Forchhammer, K. (2006) Analysis of a non-canonical NtcA-dependent promoter in Synechococcus elongatus
and its regulation by NtcA and PII. Arch Microbiol 184: 378-386.
Aldehni, M. F., Sauer, J., Spielhaupter, C., Schmid, R., and Forchhammer, K. (2003) Signal transduction protein P(II) is required
for NtcA-regulated gene expression during nitrogen deprivation in the cyanobacterium Synechococcus elongatus strain
PCC 7942. J Bacteriol 185: 2582-2591.
Alfonso, M., Perewoska, I., and Kirilovsky, D. (2001) Redox control of ntcA gene expression in Synechocystis sp. strain PCC
6803. Nitrogen availability and electron transport regulate the levels of the NtcA protein. Plant Physiol 125: 969-981.
Alge, D., and Peschek, G. A. (1993) Identifi cation and characterization of the ctaC ( coxB ) gene as part of an operon encoding
subunits I, II, and III of the cytochrome c oxidase (cytochrome aa3 ) in the cyanobacterium Synechocystis PCC 6803.
Biochem Biophys Res Commun 191: 9-17.
Alge, D., Wastyn, M., Mayer, C., Jungwirth, C., Zimmermann, U., Zoder, R., Fromwald, S., and Peschek, G. A. (1999) Allosteric
properties of cyanobacterial cytochrome c oxidase: Inhibition of the coupled enzyme by ATP and stimulation by ADP.
IUBMB Life 48: 187-197.