RpoS controls the expression and the transport of the AlgE1-7 epimerases in Azotobacter vinelandii

FEMS Microbiology Letters
S MorenoM Cocotl-Yañez

Abstract

Azotobacter vinelandii produces differentiated cells, called cysts, surrounded by two alginate layers, which are necessary for their desiccation resistance. This alginate contains variable proportions of guluronate residues, resulting from the activity of seven extracytoplasmic epimerases, AlgE1-7. These enzymes are exported by a system secretion encoded by the eexDEF operon; mutants lacking the AlgE1-7 epimerases, the EexDEF or the RpoS sigma factor produce alginate, but are unable to form desiccation resistant cysts. Herein, we found that RpoS was required for full transcription of the algE1-7 and eexDEF genes. We found that the AlgE1-7 protein levels were diminished in the rpoS mutant strain. In addition, the alginate produced in the absence of RpoS was more viscous in the presence of proteases, a phenotype similar to that of the eexD mutant. Primer extension analysis located two promoters for the eexDEF operon, one of them was RpoS-dependent. Thus, during encysting conditions, RpoS coordinates the expression of both the AlgE1-7 epimerases and the EexDEF protein complex responsible for their transport.

References

Dec 1, 1978·Canadian Journal of Microbiology·W J Page, M von Tigerstrom
May 1, 1992·Applied and Environmental Microbiology·A BaliC Kennedy
Mar 1, 1991·Proceedings of the National Academy of Sciences of the United States of America·J Kato, A M Chakrabarty
Jun 1, 1990·Journal of Bacteriology·C E Chitnis, D E Ohman
Oct 14, 1964·Biochemical and Biophysical Research Communications·W A BulenJ R LeComte
Mar 17, 1983·Nature·R N Reusch, H L Sadoff
Aug 15, 1995·Proceedings of the National Academy of Sciences of the United States of America·C D HershbergerA M Chakrabarty
Apr 1, 1994·Journal of Bacteriology·M J FranklinD E Ohman
May 1, 1994·Journal of Bacteriology·H ErtesvågS Valla
Mar 13, 2001·Environmental Microbiology·H K HøidalS Valla
Feb 16, 2002·Methods : a Companion to Methods in Enzymology·K J Livak, T D Schmittgen
Sep 20, 2007·Journal of Molecular Microbiology and Biotechnology·Raúl NoguezGuadalupe Espín

❮ Previous
Next ❯

Citations

Nov 22, 2020·International Journal of Biological Macromolecules·Fangfang CiXiangzhao Mao

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.