Regulation of succinoglycan and galactoglucan biosynthesis in Sinorhizobium meliloti.
نویسندگان
چکیده
Sinorhizobium meliloti (Rhizobium meliloti) 2011 has the ability to produce the two acidic exopolysaccharides succinoglycan (EPS I) and galactoglucan (EPS II). EPS I is a branched heteropolysaccharide composed of octasaccharide repeating units, whereas EPS II is a linear heteropolysaccharide consisting of disaccharide subunits. The exo-exs and exp gene clusters are involved in the biosynthesis of EPSI and EPSII, respectively. EPSI and EPSII biosynthesis genes are differentially expressed resulting in a complex regulation of EPS production in S. meliloti. The phosphate concentration was identified as an important factor affecting the expression of exp genes.
منابع مشابه
The ExpR/Sin quorum-sensing system controls succinoglycan production in Sinorhizobium meliloti.
Sinorhizobium meliloti is a gram-negative soil bacterium capable of forming a symbiotic nitrogen-fixing relationship with its plant host, Medicago sativa. Various bacterially produced factors are essential for successful nodulation. For example, at least one of two exopolysaccharides produced by S. meliloti (succinoglycan or EPS II) is required for nodule invasion. Both of these polymers are pr...
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متن کاملB i osyn t hes i s of the exopo I ysacc ha r i de galactoglucan in Sinorhizobiurn rneliloti is subject to a complex control by the phosphate = dependent regulator PhoB and the proteins
Lehrstuhl fur Genetik, Fakultat fur Biologie, Universitdt Bielefeld, Postfach 100131, D-33501 Bielefeld, Germany The soil bacterium Sinorhizobium meliloti (Rhizobium meliloti) has the ability to produce the alternative exopolysaccharide galactoglucan (EPS II) in addition to succinoglycan (EPS I). In the wild-type strain EPS II production is induced by phosphate-limiting conditions or by extra c...
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ورودعنوان ژورنال:
- Journal of molecular microbiology and biotechnology
دوره 4 3 شماره
صفحات -
تاریخ انتشار 2002