Transcriptional Regulation and Signal-Peptide-Dependent Secretion of Exolevanase (LsdB) in the Endophyte Gluconacetobacter diazotrophicus
Gluconacetobacter diazotrophicus utilizes plant sucrose with a constitutively expressed levansucrase (LsdA), producing extracellular levan, which may be degraded under energetically unfavored conditions. Reverse transcriptase-PCR analysis revealed that lsdA and the downstream exolevanase gene (lsdB)...
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Published in | Applied and Environmental Microbiology Vol. 75; no. 6; pp. 1782 - 1785 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Washington, DC
American Society for Microbiology
01.03.2009
American Society for Microbiology (ASM) |
Subjects | |
Online Access | Get full text |
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Summary: | Gluconacetobacter diazotrophicus utilizes plant sucrose with a constitutively expressed levansucrase (LsdA), producing extracellular levan, which may be degraded under energetically unfavored conditions. Reverse transcriptase-PCR analysis revealed that lsdA and the downstream exolevanase gene (lsdB) form an operon. lsdB transcription was induced during growth with low fructose concentrations (0.44 to 33 mM) and repressed by glucose. Transport of LsdB to the periplasm involved N-terminal signal peptide cleavage. Type II secretion mutants failed to transfer LsdB across the outer membrane, impeding levan hydrolysis. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 Corresponding author. Mailing address: Laboratorio Interacciones Planta-Microorganismos, Centro de Ingeniería Genética y Biotecnología (CIGB), Apartado 6162, Habana 10600, Cuba. Phone: 53-7-2716022. Fax: 53-7-331779. E-mail: lazaro.hernandez@cigb.edu.cu |
ISSN: | 0099-2240 1098-5336 1098-6596 |
DOI: | 10.1128/AEM.01887-08 |