ライフサイエンスコーパス: S. meliloti

1 S. meliloti also produces sulfated cell surface polysacc

2 S. meliloti ExpR activates transcription of genes involv

3 S. meliloti has three quorum-sensing systems (Sin, Tra,

4 S. meliloti Hfq is involved in controlling the populatio

5 S. meliloti lpsB complements a mutant of R. leguminosaru

6 S. meliloti MsbA2 is required for the invasion of nodule

7 S. meliloti Nod factor is a lipochitooligosaccharide tha

8 S. meliloti nodulation factor treatments of MtROP9i led

9 S. meliloti NRG185 produces oligosaccharides that are al

10 S. meliloti produces Nod factor, which elicits the forma

11 S. meliloti requires exogenous CO(2) for growth and may

12 S. meliloti rpoA encodes a 336-amino-acid, 37-kDa protei

13 S. meliloti synthesizes an unusual sulfate-modified form

14 S. meliloti unable to produce the exopolysaccharide succ

15 S. meliloti wild-type strain Rm1021 requires production

16 S. meliloti, a symbiont of leguminous plants, synthesize

17 hia coli BL21 (DE3) engineered to express 11 S. meliloti nod genes.

18 Only 28% of the 462 S. meliloti cell cycle-regulated genes were also transcr

19 In addition, S. meliloti cells constitutively producing Nod factors w

20 ation of NCR247 lowered its activity against S. meliloti.

21 and exhibited antimicrobial activity against S. meliloti.

22 ns influenced the activity of NCR247 against S. meliloti.

23 An S. meliloti relA mutant which cannot produce ppGpp was p

24 In addition, an S. meliloti lpsB mutant that is defective at a stage in

25 We have previously identified an S. meliloti Tn5 insertion mutant, S9, which is specifica

26 We recently identified an S. meliloti two-component sensory histidine kinase, CbrA

27 Our studies of an S. meliloti loss-of-function hfq mutant have revealed th

28 Through detailed analysis of an S. meliloti mutant incapable of producing ppGpp, we show

29 sistent with the functional expression of an S. meliloti phosphoglycerol transferase gene.

30 es (amplified by inverse PCR) as a probe, an S. meliloti genomic library was screened, and two overla

31 d to compatibility; most importantly, (v) an S. meliloti Rm41 derivative, carrying exo genes from an

32 nor novel lipid of R. leguminosarum 3841 and S. meliloti.

33 onal activation in both R. leguminosarum and S. meliloti.

34 the genomic and structural levels, PhiM9 and S. meliloti phage PhiM12 have a small number of open rea

35 of structure-related genes in both PhiM9 and S. meliloti-infecting T4 superfamily phage PhiM12, which

36 n when B. japonicum produced the appropriate S. meliloti Nod factor.

37 eobacteria with similar ecological niches as S. meliloti, suggesting that the CtrA cell cycle regulat

38 tions involve ecotype-strain specificity, as S. meliloti Rm41 and NRG247 are Fix+ (compatible) on M.

39 noglycan oligosaccharide populations between S. meliloti strains; (iv) the structural nature of the s

40 n the establishment of the symbiosis between S. meliloti and its host Medicago sativa.

41 Symbiosis between S. meliloti and its plant host alfalfa is dependent on b

42 pment of a nitrogen-fixing symbiosis between S. meliloti and its plant hosts.

43 be crucial for the chronic infection of both S. meliloti and B. abortus.

44 biosynthesis of exopolysaccharides (EPS) by S. meliloti.

45 In addition, MtFNSII-2 was inducible by S. meliloti and methyl jasmonate treatment, whereas MtFN

46 Symbiotic infection by S. meliloti requires an osmosensory two-component system

47 Alfalfa nodule invasion by S. meliloti can be mediated by any one of three symbioti

48 st one of two exopolysaccharides produced by S. meliloti (succinoglycan or EPS II) is required for no

49 forms of certain polysaccharides produced by S. meliloti are crucial for establishing this symbiosis.

50 Interestingly, the EPS II produced by S. meliloti in low-phosphate conditions does not allow t

51 it, whereas the oligosaccharides produced by S. meliloti Rm41 include many nonsuccinylated subunits,

52 biotically active polysaccharide produced by S. meliloti wild-type strain Rm1021 is succinoglycan.

53 the second major EPS known to be produced by S. meliloti, but typically is expressed only under condi

54 rmine which exopolysaccharide is produced by S. meliloti.

55 sport suggests that substrates recognized by S. meliloti DctA must have appropriately spaced carbonyl

56 e nodulation of alfalfa (Medicago sativa) by S. meliloti.

57 invasion process requires the synthesis, by S. meliloti, of at least one of the two symbiotically im

58 l stages during invasion of M. truncatula by S. meliloti.

59 oteobacterial pathogens and might be used by S. meliloti to sense host cues during infection.

60 Within specialized host cells, S. meliloti differentiates into highly polyploid, enlarg

61 f understanding of the physiological changes S. meliloti cells go through during the early stages of

62 ated this by constructing and characterizing S. meliloti mutants in the lpxXL and acpXL genes, which

63 After inoculation with compatible S. meliloti, LYK3:GFP puncta are relatively stable.

64 ting for the inability of lpcC to complement S. meliloti lpsB mutants.

65 custom Affymetrix GeneChip with the complete S. meliloti genome and approximately 10,000 probe sets f

66 wo new avenues for understanding the complex S. meliloti-alfalfa interactions which occur during symb

67 We have constructed S. meliloti mutants that lack HPrK or that lack key amin

68 zobium meliloti or to the invasion defective S. meliloti mutant, exoA.

69 ant to wild-type and succinoglycan-deficient S. meliloti at the early time point of 3 days postinocul

70 tula inoculated with succinoglycan-deficient S. meliloti more strongly express an unexpectedly large

71 We show that, when starved, dividing S. meliloti bet hedge by forming two daughter cells with

72 t intracellular regulatory pathways to drive S. meliloti endoreduplication and differentiation during

73 zed by R. leguminosarum bv viciae expressing S. meliloti nod genes, but the plants were yellow and se

74 ithout the small 83 amino acid protein FeuN, S. meliloti cells are unable to grow, and this phenotype

75 mutants in a genetic screen designed to find S. meliloti mutants that had abnormal succinate-mediated

76 d lipid A is important, but not crucial, for S. meliloti chronic infection and that BacA must have an

77 ght microscopy after staining with X-Gal for S. meliloti expressing a constitutive GUS gene, by confo

78 the SMc01113 gene is absolutely required for S. meliloti symbiosis with alfalfa and also for the prot

79 ich we refer to here as the mel system, for "S. meliloti."

80 ExoR(c20) was isolated directly from S. meliloti periplasm to identify its N-terminal amino a

81 ion and characterization of a ctrA gene from S. meliloti.

82 vitro, we reconstituted RNAP holoenzyme from S. meliloti alpha and E. coli beta, beta', and sigma sub

83 inguishable from those of NodD isolated from S. meliloti.

84 AcpXL purified from S. meliloti expressing pSSB-1 is fully acylated, mainly

85 ned similar results using purified RNAP from S. meliloti.

86 nce responses, and other functions that give S. meliloti an advantage in its specialized niche.

87 important implications for understanding how S. meliloti polysaccharides are functioning in the plant

88 In S. meliloti, exoR and the exoS-chvI two-component system

89 In S. meliloti, ExoS/ChvI is a key regulator of gene expres

90 ribute to the release of free fatty acids in S. meliloti, neither one can use phospholipids as substr

91 encodes an LPS sulfotransferase activity in S. meliloti.

92 -mediated regulation of stress adaptation in S. meliloti.

93 opriate GalA donor substrate is available in S. meliloti membranes.

94 cycle-dependent regulons of CtrA and DnaA in S. meliloti and C. crescentus.

95 they do not stimulate nod gene expression in S. meliloti, the flavonoids naringenin, eriodictyol, and

96 t LPS might not have a symbiotic function in S. meliloti.

97 ctrA is also an essential gene in S. meliloti, and it is expressed similarly to the autore

98 oxes from other phosphate-regulated genes in S. meliloti and to the consensus PHO box in Escherichia

99 for the regulation of core glycosylation in S. meliloti and other bacteria containing LpcC orthologs

100 However, in S. meliloti, free-living cells of the cpdR1-null mutant

101 Deletion of hprK in S. meliloti enhanced catabolite repression caused by suc

102 tional LPS sulfotransferase activity(ies) in S. meliloti that can compensate for the loss of LpsS.

103 enzymology and genetics of PHB metabolism in S. meliloti have been well characterized, phasins have n

104 ich quorum sensing downregulates motility in S. meliloti.

105 ng of the mechanisms that govern motility in S. meliloti.

106 rmined the nature of the expR101 mutation in S. meliloti.

107 s of R. leguminosarum and R. etli but not in S. meliloti or Escherichia coli.

108 ent open reading frames, podJ1 and podJ2, in S. meliloti.

109 e of three quorum sensing systems present in S. meliloti, controls the production of the symbioticall

110 hat has not been characterized previously in S. meliloti.

111 FixJ binds to the nifA and fixK promoters in S. meliloti and induces expression of the corresponding

112 e involved in more than carbon regulation in S. meliloti and suggest that the phenotypes observed occ

113 ps, including Brucella; however, its role in S. meliloti has not been investigated.

114 lain the requirements for RpoH1 and RpoH2 in S. meliloti and that there must be other crucial targets

115 another possible quorum sensing system(s) in S. meliloti.

116 iple glycosyl transferase activities seen in S. meliloti 2011 membranes.

117 w that the ExpR/Sin quorum-sensing system in S. meliloti is involved in the regulation of genes respo

118 Our data indicate that in S. meliloti, and possibly in other Rhizobiaceae species,

119 o facilitate our studies of transcription in S. meliloti, we cloned and characterized the gene for th

120 ays an important role in manganese uptake in S. meliloti.

121 erated selection procedure, four independent S. meliloti dctA mutants were isolated that retained som

122 The inferred S. meliloti RpoH promoter consensus sequences share feat

123 Transfer of pMJK-1 into S. meliloti 1021 results in heterologous expression of 1

124 entified in this manner and transferred into S. meliloti, in which they also directed the expression

125 Using green fluorescent protein-labeled S. meliloti cells, we have shown that there are signific

126 eliloti engages in a symbiosis with legumes: S. meliloti elicits the formation of plant root nodules

127 m the recently characterized cyanophage-like S. meliloti phages of the PhiM12 group.

128 and lsrB genes are expressed in free-living S. meliloti cells, but they are not required for cell gr

129 Expression profiling of free-living S. meliloti grown with the plant signal molecule luteoli

130 Analysis of free-living S. meliloti strains with mutations in genes related to n

131 s in LPS structure can affect the ability of S. meliloti to form an effective symbiosis.

132 to play an important role in the ability of S. meliloti to successfully invade its host, also helps

133 NodD, we assayed the DNA binding activity of S. meliloti NodD1 treated with the flavonoid inducer lut

134 cell growth that enabled global analysis of S. meliloti cell cycle-regulated gene expression.

135 germinating seeds, we assayed chemotaxis of S. meliloti towards betonicine, choline, glycine betaine

136 Coexpression of S. meliloti aqpS and arsC in a strain of E. coli lacking

137 of two cpdR homologues, cpdR1 and cpdR2, of S. meliloti that encode single-domain response regulator

138 Derivatives of S. meliloti strain Rm1021 carrying an lpsB mutation are

139 To study the coordinate differentiation of S. meliloti and its legume partner during nodule develop

140 Our discovery of S. meliloti chemotaxis to plant-derived QACs adds anothe

141 lay a greater role in the overall fitness of S. meliloti both during the free-living stage and in its

142 ct on the lipid A in the free-living form of S. meliloti, is essential for the chronic infection.

143 sure liquid chromatographic fractionation of S. meliloti culture filtrate extracts revealed at least

144 Searching the genome of S. meliloti, we identified a potential lysophospholipase

145 ystem (PTS) have been found in the genome of S. meliloti.

146 Growth of S. meliloti is modelled in three ecological niches (bulk

147 ay an important role in supporting growth of S. meliloti near germinating seeds of alfalfa.

148 h 7, 4'-dihydroxyflavone, a major inducer of S. meliloti nod genes, completely restored nodulation.

149 ever, luteolin, the plant-derived inducer of S. meliloti's nod genes, is not required for mature biof

150 ave previously shown that the sinRI locus of S. meliloti encodes a quorum-sensing system that plays a

151 This novel locus of S. meliloti is designated the cgm (cyclic glucan modific

152 Mapping of S. meliloti mutations conferring resistance to PhiM12, N

153 The lipid A molecules of S. meliloti and B. abortus are unusually modified with a

154 system also seems to regulate a multitude of S. meliloti genes, including genes that participate in l

155 A SMc01003-deficient mutant of S. meliloti transiently accumulates diacylglycerol, sugg

156 er classes of K-antigen-defective mutants of S. meliloti AK631 exhibit unique patterns of sensitiviti

157 ysaccharides is unclear, although mutants of S. meliloti with reduced LPS sulfation exhibit symbiotic

158 homology (39% amino acid identity) to Pcs of S. meliloti.

159 that ExoR binds to ExoS in the periplasm of S. meliloti to inhibit ExoS/ChvI activity, and that ExoR

160 and ChvI, and localizes to the periplasm of S. meliloti.

161 nodulation or nitrogen fixation phenotype of S. meliloti.

162 fact, enhances the symbiotic productivity of S. meliloti 1021 with the host plant Medicago truncatula

163 f K antigen and the symbiotic proficiency of S. meliloti AK631.

164 is of the whole-genome expression profile of S. meliloti reveals that the ExpR/Sin quorum-sensing sys

165 document complex transcriptional profiles of S. meliloti in different environments.

166 s system in which to study the regulation of S. meliloti genes could provide an important tool for ou

167 erize the global transcriptional response of S. meliloti rpoH1, rpoH2, and rpoH1 rpoH2 mutants during

168 genomic library and discovered a segment of S. meliloti DNA which allows Ralstonia eutropha to grow

169 We utilized the genomic sequence of S. meliloti to identify an open reading frame, SMc04267

170 n the bacteria expressed the complete set of S. meliloti nod genes.

171 ith both free-living and symbiotic states of S. meliloti.

172 different species of rhizobia in a strain of S. meliloti lacking endogenous NodD activity.

173 This phylogenetic and structural study of S. meliloti-infecting T4 superfamily phage PhiM9 provide

174 n total lipids from R. leguminosarum 3841 or S. meliloti 1021 were added.

175 In planktonic S. meliloti, MucR properly coordinates a diverse set of

176 The predicted S. meliloti cell cycle regulon of CtrA, but not that of

177 acterial BacA protein is critical to prevent S. meliloti from being hypersensitive toward NCR AMPs.

178 leguminosarum bv viciae strain that produced S. meliloti Nod factor.

179 ated with wild-type, succinoglycan-producing S. meliloti more strongly express genes encoding transla

180 determined that BacA specifically protected S. meliloti against oxidized NCR247.

181 tand the role of aqpS in arsenic resistance, S. meliloti aqpS and arsC were disrupted individually.

182 ound that protein exudation in the M. sativa-S. meliloti interaction caused an increase in the secret

183 rs were identified in the recently sequenced S. meliloti genome.

184 t and the physiology of the free-living soil S. meliloti before and during the establishment of nodul

185 Therefore, like E. coli and other species, S. meliloti requires only one groEL gene for viability,

186 3841 genomic DNA library in the host strain S. meliloti 1021.

187 itionally, during early stages of symbiosis, S. meliloti is presented with an oxidative burst that mu

188 We leveraged synchronized S. meliloti populations to determine how treatment with

189 Our results demonstrate that S. meliloti alpha functions are conserved in heterologou

190 mutation in E. coli rpoA, demonstrating that S. meliloti alpha supports RNAP assembly, sequence-speci

191 It was previously reported that S. meliloti cell surface polysaccharides are also covale

192 We show that S. meliloti CpdR1 has a polar localization pattern and a

193 Previous studies had shown that S. meliloti 1021 mutants that produce increased levels o

194 the properties of agl mutants suggests that S. meliloti possesses at least one additional alpha-gluc

195 The S. meliloti bluB mutant is unable to grow in minimal med

196 The S. meliloti cpdR1-null mutant can invade the host cytopl

197 The S. meliloti genome encodes 14 of these alternative sigma

198 The S. meliloti gltA gene was mutated by inserting a kanamyc

199 The S. meliloti iolA (mmsA) gene product seems to be involve

200 The S. meliloti ML beta-glucan participates in bacterial agg

201 Since both the S. meliloti and B. abortus bacA mutants have an increase

202 As in C. crescentus, the S. meliloti PodJ1 protein appears to act as a polarity b

203 ffect on transcriptional activation from the S. meliloti dctA promoter in vitro.

204 suggest that events demonstrated here in the S. meliloti-alfalfa association may be widely important

205 suggest that AqpS is the only protein of the S. meliloti ars operon that facilitates transport of ars

206 tic approach, we identified a homolog of the S. meliloti carbohydrate sulfotransferase, LpsS, in Meso

207 mechanisms governing the alterations of the S. meliloti cell cycle in planta are largely unknown.

208 molecule also inhibits the expression of the S. meliloti exp genes, responsible for the production of

209 due entirely to LpsB, since membranes of the S. meliloti lpsB mutant 6963 do not glycosylate Kdo(2)-[

210 d mass spectrometry, and the analysis of the S. meliloti NRG247 oligosaccharides showed that this str

211 To achieve polyploidy, the S. meliloti cell cycle program must be altered to uncoup

212 iporter], and arsC (arsenate reductase), the S. meliloti ars operon includes an aquaglyceroporin (aqp

213 However, our finding that the S. meliloti bacA mutant also has an increased sensitivit

214 We show that the S. meliloti CtrA belongs to the CtrA-like family of resp

215 The results of this study suggest that the S. meliloti Lon protease is important for controlling tu

216 These results indicate that the S. meliloti stringent response has roles in both succino

217 ur studies indicate that, in contrast to the S. meliloti-Medicago model symbiosis, bacteroids in the

218 Any one of three S. meliloti polysaccharides, succinoglycan, EPS II, or K

219 Moreover, adding Nod Factor antibody to S. meliloti cells inhibits biofilm formation, while chit

220 Contrary to S. meliloti, S. fredii HH103 showed little or no sensiti

221 This pathway is likely not limited to S. meliloti as suggested by the presence of homologous g

222 lates this type of specificity pertaining to S. meliloti strain Rm41.

223 In pathogenic bacteria closely related to S. meliloti, exoS-chvI homologues are required for virul

224 hibits a reduced transcriptional response to S. meliloti, indicating that the machinery responsible f

225 nsp2) showed no transcriptional response to S. meliloti, suggesting that the encoded proteins are re

226 bination with the use of flavone pre-treated S. meliloti cells, completely restored nodulation in fla

227 This report shows that M. truncatula-S. meliloti interactions involve ecotype-strain specific

228 of N-acyl homoserine lactones (AHLs) in two S. meliloti strains, Rm1021 and Rm41.

229 rimeric oligosaccharides (STOs) from the two S. meliloti strains were compared by chromatography and

230 nitrogen stress response (NSR) of wild type S. meliloti Rm1021, and isogenic strains missing both PI

231 Membranes of the wild-type S. meliloti strain 2011 catalyze the glycosylation of Kd

232 oserine lactones (AHLs) by two commonly used S. meliloti strains, AK631 and Rm1021.

233 for their microscopic nodule phenotype using S. meliloti constitutively expressing lacZ.

234 In vivo, S. meliloti rpoA expressed in Escherichia coli complemen

235 we discovered that in the absence of VLCFAs, S. meliloti produces novel pentaacylated lipid A species

236 gene sma0113 as needed for strong SMCR when S. meliloti was grown in succinate plus lactose, maltose

237 These results imply that, when S. meliloti is exposed to environmental arsenate, arsena

238 -fold more in this interaction compared with S. meliloti alone.

239 ntly reduced nodulation when inoculated with S. meliloti.

240 ecreted in the incompatible interaction with S. meliloti.

241 la A17, the Fix phenotypes are reversed with S. meliloti NRG185 and NRG34, and there is a correlation

242 tula A17, and the phenotype is reversed with S. meliloti NRG185.