TY  - JOUR
AB  - Background

Sigma factors are one of the components of RNA polymerase holoenzymes, and an essential factor of transcription initiation in bacteria. Corynebacterium glutamicum possesses seven genes coding for sigma factors, most of which have been studied to some detail; however, the role of SigD in transcriptional regulation in C. glutamicum has been mostly unknown.
Results

In this work, pleiotropic effects of sigD overexpression at the level of phenotype, transcripts, proteins and metabolites were investigated. Overexpression of sigD decreased the growth rate of C. glutamicum cultures, and induced several physiological effects such as reduced culture foaming, turbid supernatant and cell aggregation. Upon overexpression of sigD, the level of Cmt1 (corynomycolyl transferase) in the supernatant was notably enhanced, and carbohydrate-containing compounds were excreted to the supernatant. The real-time PCR analysis revealed that sigD overexpression increased the expression of genes related to corynomycolic acid synthesis (fadD2, pks), genes encoding corynomycolyl transferases (cop1, cmt1, cmt2, cmt3), L, D-transpeptidase (lppS), a subunit of the major cell wall channel (porH), and the envelope lipid regulation factor (elrF). Furthermore, overexpression of sigD resulted in trehalose dicorynomycolate accumulation in the cell envelope.
Conclusions

This study demonstrated that SigD regulates the synthesis of corynomycolate and related compounds, and expanded the knowledge of regulatory functions of sigma factors in C. glutamicum.
DA  - 2017
DO  - 10.1186/s12866-017-1067-6
KW  - Corynebacterium glutamicum Sigma factor SigD Mycomembrane Trehalose dicorynomycolate
LA  - eng
IS  - 1
PY  - 2017
SN  - 1471-2180
T2  - BMC Microbiology
TI  - Physiological roles of sigma factor SigD in Corynebacterium glutamicum
UR  - https://nbn-resolving.org/urn:nbn:de:0070-pub-29124198
Y2  - 2024-11-22T08:36:41
ER  -