The soybean cultivar specificity gene noIX is present, expressed in a nodD-dependent manner, and of symbiotic significance in cultivar-nonspecific strains of Rhizobium (Sinorhizobium) fredii
Rhizobium (now Sinorhizobium) fredii is a symbiotic nitrogen-fixing bacterium that can nodulate soybean in a cultivar-specific manner. This process is governed by a set of negatively acting nodulation genes termed noIXWBTUV. These genes prevent R. fredii strain USDA257 from infecting soybean cultivars such as McCall, but they do not block nodulation of cultivar Peking. R. fredii strain USDA191 contains DNA sequences that hybridize to noIXWBTUV, yet it forms normal nitrogen-fixing nodules on both McCall and Peking soybean. These sequences were isolated and their structure and function examined in comparison to noIXWBTUV of strain USDA257. Restriction maps of the two loci are identical, as is a 2∙4 kb DNA sequence that corresponds to noIX and its promoter region. Expression of noIX by strain USDA191 is flavonoid-dependent in culture and readily detectable in nodules. The gene is not inducible in a mutant of strain USDA191 that lacks the regulatory nodD1 gene, and its expression is greatly attenuated in a nodD2 mutant. noIX is also present and flavonoid-inducible in HH103, a second R. fredii strain that nodulates McCall soybean normally. Inactivation of noIX in strain HH103, USDA191 or USDA257 leads to retardation of initial nodulation rates on soybean cultivars such as Peking and to acquisition of the capacity to form nitrogen-fixing nodules on two species of Erythrina. noIX is thus of symbiotic significance in all three strains, even though it regulates soybean cultivar specificity only in strain USDA257.
AppelbaumE. R.,
ThompsonD. V.,
IdlerK.,
ChartrainN.1988; Rbizobium japonicum USD A 191 has two nodD genes that differ in primary structure and function.. J Bacteriol 170:12–20
BalattiP. A.,
PueppkeS.G.1992; Identification of North American soybean lines that form nitrogen-fixing nodules with Rhizobium fredii USDA257.. Can J Plant Sci 72:49–55
Buendía-ClaveríaA. M.,
ChamberM.,
Ruiz-SainzJ. E.1989; A comparative study of the physiological characteristics, plasmid content and symbiotic properties of different Rhizobium fredii strains.. Syst Appl Microbiol 12:203–209
ChatterjeeA.,
BalattiP. A.,
GibbonsW.,
PueppkeS. G.1990; Interaction of Rhizobium fredii and nodulation mutants derived from it with the agronomically improved soybean cultivar McCall.. Planta 180:303–311
DowdleS. F.,
BohloolB. B.1985; Predominance of fastgrowing Rhizobium japonicum in a soybean field in the People’s Republic of China.. Appl Environ Microbiol 50:1171–1176
FisherR. F.,
LongS. R.1993; Interactions of NodD at the nod box: NodD binds to two distinct sites on the same face of the helix and induces a bend in the DNA.. J Mol Biol 233:336–348
FriedmanA. M.,
LongS. R.,
BrownS. E.,
BuikemaW. J.,
AusubelF. M.1982; Construction of a broad host range cosmid cloning vector and its use in the genetic analysis of Rbizobium mutants.. Gene 18:289–296
KosslakR. M.,
BooklandR.,
BarkeiJ.,
PaarenH. E.,
AppelbaumE. R.1987; Induction of Bradyrhizobium japonicum common nod genes by isoflavones isolated from Glycine max.. Proc Natl Acad Sci USA 84:7428–7432
KovácsL. G.,
BalattiP. A.,
KrishnanH. B.,
PueppkeS. G.1995; Transcriptional organization and expression of nolXWBTUV, a locus that regulates cultivar-specific nodulation of soybean by Rhizobium fredii USDA257.. Mol Microbiol 17:923–933
KrishnanH. B.,
PueppkeS. G.1991; Sequence and analysis of the nodABC region of Rhizobium fredii USDA257, a nitrogenfixing symbiont of soybean and other legumes.. Mol Plant-Microbe Interact 4:512–520
KrishnanH. B.,
PueppkeS. G.1994a; Cultivar-specificity genes of the nitrogen-fixing soybean symbiont, Rhizobium fredii USDA257, also regulate nodulation of Erythrina spp.. Am J Bot 81:38–45
KrishnanH. B.,
KuoC.-L.,
PueppkeS. G.1995; Elaboration of flavonoid-induced proteins by the nitrogen-fixing soybean symbiont Rhizobium fredii is regulated by both nodD1 and nodD2, and is dependent on the cultivar-specificity locus, nolXWBTUV.. Microbiology 141:2245–2251
MeinhardtL. W.,
KrishnanH. B.,
BalattiP. A.,
PueppkeS. G.1993; Molecular cloning and characterization of a sym plasmid locus that regulates cultivar-specific nodulation of soybean by Rhizobium fredii USDA257.. Mol Microbiol 9:17–29
PrestonG.,
HuangH.-C.,
HeS. Y.,
CollmerA.1995; The HrpZ proteins of Pseudomonas syringae pvs. syringae, glycinea, and tomato are encoded by an operon containing Yersinia ysc homologs and elicit the hypersensitive response in tomato but not soybean.. Mol Plant-Microbe Interact 8:717–732
Rodriguez-NavarroD. N.,
Ruiz-SainzJ. E.,
Buendia-ClaveriaA. M.,
SantamariaC.,
BalattiP. A.,
KrishnanH. B.,
PueppkeS. G.1996; Characterization of rhizobia from nodulated soybean [Glycine max (L.)Merr.] growing in Vietnam.. Syst Appl Microbiol 19:240–248
Scott-CraigJ. S.,
GuerinotM. L.,
ChelmB. K.1991; Isolation of Bradyrhizobium japonicum DNA sequences that are transcribed at high levels in bacteroids.. Mol Gen Genet 228:356–360
SimonR.,
PrieferU.,
PühlerA.1983; A broad host range mobilization system for in vivo genetic engineering: transposon mutagenesis in Gram-negative bacteria.. Bio/Technology 1:784–791
Van GijsegemF,
GoughC.,
ZischekC.,
NiqueuxE.,
ArlatM.,
GeninS.,
BarberisP.,
GermanS.,
CastelloP.,
BoucherC.1995; The hrp gene locus of Pseudomonas solanacearum, which controls the production of a type III secretion system, encodes eight proteins related to components of the bacterial flagellar biogenesis complex.. Mol Microbiol 15:1095–1114
The soybean cultivar specificity gene noIX is present, expressed in a nodD-dependent manner, and of symbiotic significance in cultivar-nonspecific strains of Rhizobium (Sinorhizobium) fredii