Abstract
The bacteriophage Mud1(Ap('r) lac cts62) obtained from an Escherichia coli double lysogen carrying the defective Mu d1 phage and a Mu-P1 hybrid phage was utilized as a vector for phage mutagenesis of Erwinia carotovora subsp. carotovora. Among ampicillin-resistant transductants, 1.4% were auxotrophs. The wide range of different auxotrophic phenotypes recovered indicated that the insertion of Mud1 is random in the E. carotovora genome. Using His auxotrophs I showed that the expression of the lac Z gene is under the control the promoter-regulatory region of the his operon, thus demonstrating that Mud1 mutagenesis can be used to obtain gene fusions in E. carotovora. Using Mud1 mutagenesis I isolated three classes of apparently nonpathogenic mutants. (I) Mutants blocked in biosynthesis of pyrimidines or purines. (II) Mutants unable to utilize various carbon sources (pleiotrophic). (III) Mutants impaired in their ability to secrete pectolytic and proteolytic enzymes. Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber, since application of supplements to potato tuber restored the pathogenic phenotype of mutants. The class II mutant was biochemically characterized as galU. This mutation would result in accumulation of gal-l-P, UDPGal and UDPG which are toxic to bacterial growth. Bacteriophage PIKMclr100 was transferred to Erwinia carotovora subsp. carotovora. P1 was stably maintained as detected by hybridization and transfer of kanamycin resistance. Lysogens of Erwinia carotovora failed to produce any viable P1 phage. Although total DNA from P1-lysogens of Erwinia carotovora hybridized to ('32)P-labeled P1 probe, I was not able to detect P1 DNA as an extrachromosomal element. The broad host-range Inc-P plasmids RP4, R751 and pMO850 were transferred by conjugation from Escherichia coli and Pseudomonas aeruginosa to Erwinia carotovora. These plasmids were stably maintained and their antibiotic resistances were expressed in E. carotovora. Transconjugants of E. carotovora were as efficient donors of plasmids as E. coli and P. aeruginosa. Acquisition of Inc-P plasmid had no effect on pathogenic behavior of E. carotovora. Inc-P plasmid did not mobilize chromosomal markers in E. carotovora. (Abstract shortened with permission of author.)
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Claims 13
Claim · model-written summary
Among ampicillin-resistant transductants of Erwinia carotovora, 1.4% were auxotrophs.
- Taxon
- potato
Solanum tuberosume0 - Interactor
- Erwinia carotovora subsp. carotovora
Pectobacterium carotovorum subsp. carotovorume2pathogen - Outcome
- auxotrophse1
- Value
- 1.4%e1
- Qualifier
- Among ampicillin-resistant transductantse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e1“Among ampicillin-resistant transductants, 1.4% were auxotrophs”
e2“phage mutagenesis of Erwinia carotovora subsp. carotovora”
Claim · model-written summary
Class I mutants of Erwinia carotovora were nonpathogenic on potato tuber, which is attributed to lack of purine and pyrimidine at the cut surface.
- Taxon
- potatoSolanum tuberosume0
- Compound
- purine and pyrimidinee0
- Outcome
- nonpathogenice0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
Claim · model-written summary
Application of supplements to potato tuber restored the pathogenic phenotype of the mutants.
- Taxon
- potatoSolanum tuberosume3
- Treatment
- application of supplements to potato tubere3
- Outcome
- pathogenic phenotypee3
- Direction
- restorede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e3“since application of supplements to potato tuber restored the pathogenic phenotype of mutants”
Claim · model-written summary
The class II mutant of Erwinia carotovora was biochemically characterized as galU.
- Taxon
- potatoSolanum tuberosume0
- Material
- class II mutante4
- Gene
- galUe4
- Outcome
- biochemically characterizede4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e4“The class II mutant was biochemically characterized as galU”
Claim · model-written summary
Accumulation of gal-l-P, UDPGal and UDPG would be toxic to bacterial growth.
- Taxon
- potatoSolanum tuberosume0
- Compound
- gal-l-P, UDPGal and UDPGe5
- Outcome
- bacterial growthe5
- Qualifier
- would result in accumulatione5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e5“This mutation would result in accumulation of gal-l-P, UDPGal and UDPG which are toxic to bacterial growth”
Claim · model-written summary
Class III mutants of Erwinia carotovora were impaired in their ability to secrete pectolytic and proteolytic enzymes.
- Taxon
- potatoSolanum tuberosume0
- Outcome
- ability to secrete pectolytic and proteolytic enzymese6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e6“Mutants impaired in their ability to secrete pectolytic and proteolytic enzymes”
Claim · model-written summary
Lysogens of Erwinia carotovora failed to produce viable P1 phage.
- Taxon
- potatoSolanum tuberosume0
- Material
- Lysogens of Erwinia carotovorae7
- Outcome
- viable P1 phagee7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e7“Lysogens of Erwinia carotovora failed to produce any viable P1 phage”
Claim · model-written summary
P1 DNA was not detected as an extrachromosomal element in Erwinia carotovora lysogens.
- Taxon
- potatoSolanum tuberosume0
- Outcome
- detect P1 DNA as an extrachromosomal elemente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e1“I was not able to detect P1 DNA as an extrachromosomal element”
Claim · model-written summary
Inc-P plasmids RP4, R751 and pMO850 were transferred by conjugation to Erwinia carotovora.
- Taxon
- potatoSolanum tuberosume0
- Material
- Inc-P plasmids RP4, R751 and pMO850e2
- Outcome
- transferred by conjugatione2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e2“The broad host-range Inc-P plasmids RP4, R751 and pMO850 were transferred by conjugation from Escherichia coli and Pseudomonas aeruginosa to Erwinia carotovora”
Claim · model-written summary
Inc-P plasmids were stably maintained in Erwinia carotovora and their antibiotic resistances were expressed.
- Taxon
- potatoSolanum tuberosume0
- Material
- These plasmidse3
- Outcome
- stably maintainede3
- Qualifier
- antibiotic resistances were expressede3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e3“These plasmids were stably maintained and their antibiotic resistances were expressed in E. carotovora”
Claim · model-written summary
Transconjugants of Erwinia carotovora were as efficient plasmid donors as Escherichia coli and Pseudomonas aeruginosa.
- Taxon
- potatoSolanum tuberosume0
- Material
- Transconjugants of E. carotovorae4
- Outcome
- as efficient donors of plasmidse4
- Comparator
- E. coli and P. aeruginosae4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e4“Transconjugants of E. carotovora were as efficient donors of plasmids as E. coli and P. aeruginosa”
Claim · model-written summary
Acquisition of Inc-P plasmid had no effect on the pathogenic behavior of Erwinia carotovora.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- Acquisition of Inc-P plasmide5
- Outcome
- pathogenic behaviore5
- Direction
- no effecte5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e5“Acquisition of Inc-P plasmid had no effect on pathogenic behavior of E. carotovora”
Claim · model-written summary
Inc-P plasmid did not mobilize chromosomal markers in Erwinia carotovora.
- Taxon
- potatoSolanum tuberosume0
- Material
- Inc-P plasmide6
- Outcome
- mobilize chromosomal markerse6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Class I mutants were nonpathogenic due to the lack of purine and pyrimidine at the cut surface of potato tuber”
e6“Inc-P plasmid did not mobilize chromosomal markers in E. carotovora”