Abstract：
:Sinorhizobium meliloti and host legumes enter into a nitrogen-fixing, symbiotic relationship triggered by an exchange of signals between bacteria and plant. S. meliloti produces Nod factor, which elicits the formation of nodules on plant roots, and succinoglycan, an exopolysaccharide that allows for bacterial invasion and colonization of the host. The biosynthesis of these molecules is well defined, but the specific regulation of these compounds is not completely understood. Bacteria control complex regulatory networks by the production of ppGpp, the effector molecule of the stringent response, which induces physiological change in response to adverse growth conditions and can also control bacterial development and virulence. Through detailed analysis of an S. meliloti mutant incapable of producing ppGpp, we show that the stringent response is required for nodule formation and regulates the production of succinoglycan. Although it remains unknown whether these phenotypes are connected, we have isolated suppressor strains that restore both defects and potentially identify key downstream regulatory genes. These results indicate that the S. meliloti stringent response has roles in both succinoglycan production and nodule formation and, more importantly, that control of bacterial physiology in response to the plant and surrounding environment is critical to the establishment of a successful symbiosis.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Wells DH,Long SRdoi
10.1046/j.1365-2958.2002.02826.xsubject
Has Abstractpub_date
2002-03-01 00:00:00pages
1115-27issue
5eissn
0950-382Xissn
1365-2958pii
2826journal_volume
43pub_type
杂志文章abstract：:Colletotrichum lagenarium and Magnaporthe grisea are plant pathogenic fungi that produce melanin during the appressorial differentiation stage of conidial germination and during the late stationary phase of mycelial growth. Here, we report the identification of genes for two unique transcription factors, CMR1 (Colleto...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.02181.x
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doi：10.1046/j.1365-2958.2000.02055.x
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更新日期：2000-10-01 00:00:00
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pub_type： 杂志文章,评审
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pub_type： 杂志文章
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更新日期：2004-05-01 00:00:00
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更新日期：2000-03-01 00:00:00
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更新日期：1997-11-01 00:00:00
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更新日期：2002-01-01 00:00:00
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doi：
更新日期：2010-10-01 00:00:00
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更新日期：1998-01-01 00:00:00
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pub_type： 社论
doi：10.1111/mmi.13742
更新日期：2017-08-01 00:00:00
