Gene List on a Plant Tumor-inducing Plasmid, pTi-SAKURA in Agrobacterium tumefaciens MAFF301001

Extracts of the plant tumor-inducing organism Agrobacterium tumefaciens do not oxidize glucose directly to gluconic or to 2-ketogluconic acid. Such extracts contain an extremely active, cyanide-sensitive DPNH oxidase. TPNH oxidase shows little activity and pyridine nucleotide transhydrogenase appears to be absent. Hexokinase is active, glucose-6-phosphate dehydrogenase functions either as a DPN- or as a TPN-linked system, 6-phosphogluconic acid dehydrogenase is TPN-specific, and glyceraldehyde-3-phosphate dehydrogenase is DPN-specific.Evidence is presented to show that the pentose cycle operates in such preparations and also that the extent to which it functions is determined by the rate-limiting dehydrogenation and decarboxylation of 6-phosphogluconate. Thus, heptulose phosphate is formed readily from ribose-5-phosphate and much less effectively from 6-phosphogluconate. The net formation of hexose as a product of the cycle is also shown. It was possible to demonstrate under certain conditions that an effective competition exists between glyceraldehyde-3-phosphate dehydrogenase and transaldolase for available triose phosphate.From reaction rates and other data it is clear that the Entner–Doudoroff 6-phosphogluconate-splitting pathway is the major avenue of hexose phosphate utilization in cell-free extracts. Pyruvate thus formed is oxidized via the tricarboxylic acid cycle while glyceraldehyde-3-phosphate can be changed slowly into pyruvate or be recycled into hexose phosphate. The latter pathway is facilitated by the existence of a highly active fructose-1,6-diphosphatase.Whereas phosphohexoseisomerase is found to be highly active, phosphofructokinase shows very little activity, aldolase does not appear to be very effective, and the conversion of phosphoglyceric acid to pyruvate is extremely slow. For these reasons, glycolysis is considered to play a very minor role in glucose metabolism in these extracts.Data on the effects of some carbohydrate inhibitors on glucose-6-phosphate dehydrogenase and on phosphohexoseisomerase are also given.

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Import pathways of the mannityl-opines into the bacterial pathogen Agrobacterium tumefaciens: structural, affinity and in vivo approaches

Biochemical Journal ◽

10.1042/bcj20190886 ◽

2020 ◽

Vol 477 (3) ◽

pp. 615-628

Author(s):

Armelle Vigouroux ◽

Jeanne Doré ◽

Loïc Marty ◽

Magali Aumont-Nicaise ◽

Pierre Legrand ◽

...

Keyword(s):

Agrobacterium Tumefaciens ◽

Tumor Development ◽

Bacterial Pathogen ◽

Binding Mode ◽

Acid Uptake ◽

Crystal Forms ◽

Plant Tumor ◽

Structural Affinity

Agrobacterium tumefaciens pathogens use specific compounds denoted opines as nutrients in their plant tumor niche. These opines are produced by the host plant cells genetically modified by agrobacteria. They are imported into bacteria via solute-binding proteins (SBPs) in association with ATP-binding cassette transporters. The mannityl-opine family encompasses mannopine, mannopinic acid, agropine and agropinic acid. Structural and affinity data on mannopinic acid bound to SBPs are currently lacking while those of the three others mannityl opines are available. We investigated the molecular basis of two pathways for mannopinic acid uptake. MoaA was proposed as the specific SBP for mannopinic acid import in mannityl opines-assimilating agrobacteria, which was validated here using genetic studies and affinity measurements. We structurally characterized the mannopinic acid-binding mode of MoaA in two crystal forms at 2.05 and 1.57 Å resolution. We demonstrated that the non-specific SBP MotA, so far characterized as mannopine and Amadori compound importer, was also able to transport mannopinic acid. The structure of MotA bound to mannopinic acid at 2.2 Å resolution defines a different mannopinic acid-binding signature, similar to that of mannopine. Combining in vitro and in vivo approaches, this work allowed us to complete the characterization of the mannityl-opines assimilation pathways, highlighting the important role of two dual imports of agropinic and mannopinic acids. Our data shed new light on how the mannityl-opines contribute to the establishment of the ecological niche of agrobacteria from the early to the late stages of tumor development.

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Units of genetic expression in the virulence region of a plant tumor-inducing plasmid of Agrobacterium tumefaciens

MGG Molecular & General Genetics ◽

10.1007/bf00330043 ◽

1982 ◽

Vol 188 (3) ◽

pp. 418-424 ◽

Cited By ~ 29

Author(s):

V. N. Iyer ◽

H. J. Klee ◽

E. W. Nester

Keyword(s):

Agrobacterium Tumefaciens ◽

Genetic Expression ◽

Plant Tumor

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ON THE BIOSYNTHESIS OF PSEUDOURIDINE AND OF PSEUDOURIDYLIC ACID IN AGROBACTERIUM TUMEFACIENS

Canadian Journal of Biochemistry ◽

10.1139/o66-029 ◽

1966 ◽

Vol 44 (2) ◽

pp. 259-272 ◽

Cited By ~ 15

Author(s):

T. Suzuki ◽

R. M. Hochster

Keyword(s):

Agrobacterium Tumefaciens ◽

Biosynthetic Pathway ◽

Direct Synthesis ◽

Ion Concentration ◽

Sodium Arsenate ◽

Ph Optimum ◽

Crude Extracts ◽

Plant Tumor ◽

Michaelis Constants

Crude extracts prepared from the plant tumor inducing organism Agrobacterium tumefaciens were shown to convert uracil and D-ribose-5-phosphate to pseudouridine in stoichiometric amounts. The addition of the nucleotidase inhibitor sodium arsenate altered the course of the reactions involved in such a way that pseudouridylic acid became the product. Under these conditions, the latter was formed in the same relative concentrations as pseudouridine in experiments without inhibitor.The direct synthesis of pseudouridylic acid from the above precursors was found to be catalyzed by an enzyme which has been tentatively designated as "pseudouridylic acid synthetase". This enzyme was separated from the nucleotidase and purified 80-fold. Parameters such as pH optimum, required ion concentration, and Michaelis constants were determined.The data presented in this paper permit the first description of the biosynthetic pathway for pseudouridylic acid and for pseudouridine in a bacterium.

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