HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Homerová, D. Articles by Kormanec, J. Search for Related Content PubMed Articles by Homerová, D. Articles by Kormanec, J. Agricola Articles by Homerová, D. Articles by Kormanec, J.

Disruption of a glycogen-branching enzyme gene, glgB, specifically affects the sporulation-associated phase of glycogen accumulation in Streptomyces aureofaciens

Oldich Benada²

Olga Kofroová²

Bronislava euchová¹

Institute of Molecular Biology, Slovak Academy of Sciences, 842 51 Bratislava, Slovak Republic
Institute of Microbiology, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague 4, Czech Republic

³Author for correspondence: Ján Kormanec. Tel: +42 7 378 2432. Fax: +42 7 372 316. e-mail: umbijkor@savba.sk

ABSTRACT

In the course of Streptomyces differentiation, glycogen is accumulated in two discrete phases: in substrate hyphae that undergo aerial mycelium formation (phase I), and during septation of aerial hyphae (phase II). We have disrupted a previously identified gene, glgB, encoding a putative glycogen-branching enzyme in Streptomyces aureofaciens. Disruption of the gene had no profound effect on sporulation. However, the amount of glycogen-like polysaccharides, compared to wild-type (WT) S. aureofaciens, decreased in the late stage of differentiation of the glgB-disrupted strain. Absorption spectra of polysaccharides extracted from the WT and glgB-disrupted strains have shown the presence of glycogen in both strains in the first stage of differentiation (aerial mycelium formation), and unbranched glucan was detected in the glgB-disrupted strain in the late stage of differentiation. The results were confirmed by electron microscopy after silver proteinate staining of glycogen granules. Two distinct glycogen-branching enzymes, which had temporally different expression during differentiation, were detected in WT S. aureofaciens. The absence of this enzyme activity in the late stage of differentiation in the glgB mutant suggests that the product of the glgB gene is responsible for phase II glycogen accumulation.

This article has been cited by other articles:

				O. Sprusanský, B. Rezuchová, D. Homerová, and J. Kormanec Expression of the gap gene encoding glyceraldehyde-3-phosphate dehydrogenase of Streptomyces aureofaciens requires GapR, a member of the AraC/XylS family of transcriptional activators Microbiology, May 1, 2001; 147(5): 1291 - 1301. [Abstract] [Full Text]