Characterization of a rice gene induced by Pseudomonas syringae pv. syringae: requirement for the bacterial lemA gene function

Reimmann, Cornelia; Hofmann, Chr; Mauch, Félix; Dudler, Robert

doi:10.1006/pmpp.1995.1006

Cited by 39 publications

(39 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The basis for this hypothesis is the high degree of similarity (33-55%) between the predicted protein sequence of the rice (Oryza sativa L.) pir gene(s) and that of cassava HNL (Reimann et al, 1995). Expression of the rice pir gene is induced during fungal infection.…”

Section: Discussionmentioning

confidence: 99%

Cyanogenesis in Cassava1

White¹,

Arias-Garzon²,

McMahon³

et al. 1998

Plant Physiology

114

View full text Add to dashboard Cite

In the cyanogenic crop cassava (Manihot esculenta, Crantz), the final step in cyanide production is the conversion of acetone cyanohydrin, the deglycosylation product of linamarin, to cyanide plus acetone. This process occurs spontaneously at pH greater than 5.0 or enzymatically and is catalyzed by hydroxynitrile lyase (HNL). Recently, it has been demonstrated that acetone cyanohydrin is present in poorly processed cassava root food products. Since it has generally been assumed that HNL is present in all cassava tissues, we reinvestigated the enzymatic properties and tissue-specific distribution of HNL in cassava. We report the development of a rapid two-step purification protocol for cassava HNL, which yields an enzyme that is catalytically more efficient than previously reported (Hughes, J., Carvalho, F., and Hughes, M.[1994] Arch Biochem Biophys 311: 496-502). Analyses of the distribution of HNL activity and protein indicate that the accumulation of acetone cyanohydrin in roots is due to the absence of HNL, not to inhibition of the enzyme. Furthermore, the absence of HNL in roots and stems is associated with very low steady-state HNL transcript levels. It is proposed that the lack of HNL in cassava roots accounts for the high acetone cyanohydrin levels in poorly processed cassava food products.

show abstract

Section: Discussionmentioning

confidence: 99%

Cyanogenesis in Cassava1

White¹,

Arias-Garzon²,

McMahon³

et al. 1998

Plant Physiology

114

View full text Add to dashboard Cite

show abstract

“…tomato DC3000, which does not produce syringolins, revealed that the syringolin synthetase genes form a cassette that is missing in the latter genome and that contains precisely the sylA-sylE gene cluster. The biosynthesis of syringolin A is dependent on the gacA/gacS two-component system (Reimmann et al, 1995;Wäspi et al, 1998) that also regulates syringomycin biosynthesis and pathogenicity (Hrabak and Willis, 1992). Furthermore, sylD has been shown to belong to the salA regulon (Lu et al, 2005).…”

Section: Resultsmentioning

confidence: 99%

Syringolin A: Action on Plants, Regulation of Biosynthesis and Phylogenetic Occurrence of Structurally Related Compounds

Schellenberg

Ramel

Dudler

2008

Pseudomonas Syringae Pathovars and Related Pathogens – Identification, Epidemiology and Genomics

Self Cite

View full text Add to dashboard Cite

Cloning of the syringolin A synthetase genes has allowed us to build a detailed model of syringolin A synthesis based on the gene structure. This model in turn enabled us to clone the genes responsible for the synthesis of glidobactins (syn. cepafungins), antibiotics with a structure related to syringolin A that were reported to have antitumor activity, from an unknown species belonging to the order Burkholderiales. Comparisons to the approximately 700 complete eubacterial genomic sequences known resulted in the identification of a small but very intriguing group of pathogenic bacteria postulated to produce glidobacting-like molecules.

show abstract

Section: Discussionmentioning

confidence: 99%

“…Application of isolated syringolin A in micromolar concentrations onto rice plants evokes the activation of defense-related genes and induces resistance against the rice blast fungus (Wäspi et al, 1998a). However, syringolin A is redundant with respect to resistance induction because mutant P. s. syringae strains that do not synthesize syringolins are still recognized by rice plants and induce defense reactions and resistance (Reimmann et al, 1995;Wäspi et al, 1998a).…”

Section: Introductionmentioning

confidence: 99%

“…Thus, it appears likely that the observed protection of wheat by syringolin A was also the result of resistance induction. In this respect, it is interesting that the compatible SM strain of P. s. syringae that was originally isolated from wheat and that is pathogenic on this host does not produce syringolin A (Reimmann et al, 1995;Wäspi et al, 1998a).In addition to its protective effect, syringolin A has a more powerful curative effect on powdery mildew-infected wheat (Figure 2). Syringolin A is able to essentially eradicate the fungus when applied 48 hr after inoculation.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Syringolin Reprograms Wheat to Undergo Hypersensitive Cell Death in a Compatible Interaction with Powdery Mildew

2001

View full text Add to dashboard Cite

We had previously isolated and characterized syringolin A, one of the molecular determinants secreted by Pseudomonas syringae pv syringae that is perceived by nonhost plant species such as rice. Here, we show that syringolin A is recognized by wheat and that it induces the accumulation of gene transcripts and increases protection against powdery mildew when applied before inoculation. Moreover, syringolin A essentially eradicates powdery mildew from infected wheat if applied after inoculation. This curative effect is accompanied by the induction of cell death and the reactivation of pathogenesis-related genes whose transcript levels initially accumulate after powdery mildew inoculation but then decline during the later course of infection. Because syringolin A has no fungicidal activity against a variety of fungi and its action on wheat cannot be mimicked by the fungicide cyprodinil, syringolin A is hypothesized to counteract the suppression of host defense reactions imposed by the pathogen on the colonized cells. INTRODUCTIONPlants have evolved a variety of passive and active defense mechanisms against a plethora of potentially pathogenic microbes. A prominent form of an active defense response is the hypersensitive reaction, which is accompanied by localized cell death at the infection site and results in complete resistance. It has been demonstrated in many systems that these local events can induce systemic acquired resistance, that is, they cause the establishment of a physiological state in a plant that makes the plant more resistant to a variety of pathogens to which it normally would be susceptible (Hunt and Ryals, 1996;Sticher et al., 1997). A prerequisite for active defense reactions to occur is recognition of the attacking microbe by the plant. In a number of systems exhibiting race-specific resistance according to the gene-forgene concept, genes governing the recognition process have been molecularly characterized (Hammond-Kosack and Jones, 1996; Baker et al., 1997;Ellis and Jones, 1998;Nürnberger, 1999). Phenotypically, active defense reactions evoked by nonhost pathogens are very similar to the ones observed in race-specific incompatible interactions. However, the molecular events underlying the recognition process between plants and nonhost pathogens have been less well characterized, mainly because genetic analysis was hampered by the apparent redundancy built into the system.In rice, acquired resistance against the rice blast fungus Magnaporthe grisea can be induced by inoculation with the nonhost pathogen Pseudomonas syringae pv syringae (Smith and Métraux, 1991). We have recently isolated syringolin A, one of the bacterial determinants that are recognized by rice plants and cultured rice cells (Wäspi et al., 1998a;Hassa et al., 2000). Syringolin A (Figure 1) belongs to a family of small, structurally closely related peptides (syringolin A to F) that are synthesized nonribosomally and secreted by P. s. syringae (Wäspi et al., 1998a(Wäspi et al., , 1999. Application of isolated syringolin A in m...

show abstract

Characterization of a rice gene induced by Pseudomonas syringae pv. syringae: requirement for the bacterial lemA gene function

Cited by 39 publications

References 0 publications

Cyanogenesis in Cassava1

Cyanogenesis in Cassava1

Syringolin A: Action on Plants, Regulation of Biosynthesis and Phylogenetic Occurrence of Structurally Related Compounds

Syringolin Reprograms Wheat to Undergo Hypersensitive Cell Death in a Compatible Interaction with Powdery Mildew

Contact Info

Product

Resources

About