scholarly journals Comparison between Pathogenic Streptomyces scabies Isolates of Common Scab Disease

2016 ◽  
Vol 8 (2) ◽  
pp. 151-155
Author(s):  
Mohamed HOSNY ◽  
Kamal A. ABO-ELYOUSR ◽  
Mahmoud R. ASRAN ◽  
Farag A. SAEAD
Keyword(s):  
Common Scab ◽  
Pcr Amplification ◽  
Streptomyces Scabies ◽  
Agarose Gel Electrophoresis ◽  
Potato Tubers ◽  
Biochemical Tests ◽  
Highly Pathogenic ◽  
Field Crops ◽  
Dna Fragment ◽  
Reliable Marker

Streptomyces scabies (Thaxter) causes destructive and serious damages to many vegetable field crops, including potato. Fourteen pure isolates were obtained from naturally diseased potato tubers showing symptoms of common scab disease, collected from different localities of Sohag governorate, Egypt. All tested isolates were identified as S. scabies (Stc) according to morphological and biochemical tests. Isolate Stc 10 exhibited the highest activity of polyphenoloxidase enzyme, followed by isolate Stc 11, while isolate Stc 2 produced the lowest activity of this enzyme. Concerning the peroxidase activity, the isolates varied in their production; Stc 11 exhibited the highest activity enzyme, followed by isolate Stc 2, whereas isolate Stc 10 produced the lowest activity of enzyme. In regard with Tyrosine Amonnia Lyase (TAL) activity, isolate Stc 2 exhibited the highest activity, followed by isolate Stc 10, whereas isolate Stc 11 exhibited the lowest activity. Agarose gel electrophoresis of the PCR amplification products revealed a band representing the expected 279 bp DNA fragment in each DNA extracted from the highly pathogenic isolates Stc 10 and 11. The results demonstrated that PCR amplification of the nec1 gene could be used as a reliable marker for detecting pathogenic Streptomyces isolates on potato tubers.

scholarly journals Investigation of Streptomyces scabies Causing Potato Scab by Various Detection Techniques, Its Pathogenicity and Determination of Host-Disease Resistance in Potato Germplasm

Pathogens ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 760
Author(s):  
Sohaib Ismail ◽  
Bo Jiang ◽  
Zohreh Nasimi ◽  
M. Inam-ul-Haq ◽  
Naoki Yamamoto ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Common Scab ◽  
Streptomyces Scabies ◽  
Potato Cultivars ◽  
Potato Tubers ◽  
Streptomyces Species ◽  
Detection Techniques ◽  
Streptomyces Spp ◽  
Geographical Regions

Streptomyces scabies is a Gram-positive bacterial pathogen that causes common scab disease to several crops, particularly in the potato. It is a soil borne pathogen, a very devastating scab pathogen and difficult to manage in the field. Streptomyces has several species that cause common scab such as S. scabiei, S. acidiscabies, S. europaeiscabiei, S. luridiscabiei, S. niveiscabiei, S. puniciscabiei, S. reticuliscabiei, S. stelliscabiei, S. turgidiscabies, S. ipomoeae. Common scab disease harmfully affects potato economic and market value due to the presence of black spots on the tuber. Owing to its genetic diversity and pathogenicity, the determination of pathogen presence in potato fields is still challenging. In this study, S. scabies genetic diversity was measured by surveying five potato-growing areas of Pakistan during the growing season 2019. A total of 50 Streptomyces isolates, including S. scabies, S. acidiscabies, S. griseoflavus were isolated and identified based on morphologic, biochemical and molecular analysis. Virulent confirmation assays confirmed ten virulent strains of Streptomyces spp. On the potato cultivars Cardinal and Santee. Among the Streptomyces species, S. scabies showed the highest scab index, followed by S. acidiscabies and S. griseoflavus by exhibiting the scab-like lesions on potato tubers. Ten potato cultivars were screened against these virulent isolates of Streptomyces. The Faisalabad white variety showed the highest scab index followed By Cardinal, Tourag, Kuroda, Santee, Lady Rosetta, Asterix, Diamant, Faisalabad red and Sadaf. Moreover, genetic diversity and pathogenicity of Streptomyces spp. on potato tubers were also likely diverse in different geographical regions and also potato cultivars. This study represents a contribution to understanding the local interaction between potatoes and Streptomyces spp. in Pakistan. It will aid in supporting a solution for the management of this pathogen around the world.

Characterization of Streptomyces scabies mutants deficient in melanin biosynthesis

2004 ◽  
Vol 50 (9) ◽  
pp. 705-709 ◽  
Author(s):  
Julie Beauséjour ◽  
Carole Beaulieu
Keyword(s):  
Stress Resistance ◽  
Common Scab ◽  
Wild Strain ◽  
Streptomyces Scabies ◽  
Potato Tubers ◽  
Melanin Biosynthesis ◽  
Thaxtomin A ◽  
Pleiotrophic Effects ◽  
Higher Sensitivity

Streptomyces scabies, a causal agent of common scab, produces both melanin and a secondary metabolite called thaxtomin A. To establish a possible relation between melanin and thaxtomin A production in S. scabies, we carried out N-methyl-N′-nitro-N-nitrosoguanidine (NTG) mutagenesis and isolated 11 melanin-negative mutants of S. scabies EF-35. These mutants were characterized for thaxtomin A production, pathogenicity, sporulation, and stress resistance. Nine of these mutants showed a significant reduction in thaxtomin A production when compared with the wild strain. However, only a few mutants exhibited a reduced level of virulence or a loss in their ability to induce common scab symptoms on potato tubers. Other pleiotrophic effects, such as higher sensitivity to heavy metals and incapacity to sporulate under certain stress conditions, were also associated with a deficiency in melanin production.Key words: common scab, potato, secondary metabolism, stress, thaxtomin.

scholarly journals Role of Certain Potato Tubers Constituents in Their Susceptibility to Bacterial Common Scab Caused by Streptomyces scabies

2016 ◽  
Vol 5 (1) ◽  
pp. 45-51
Author(s):  
Kamal A. M. Abo-Elyousr ◽  
Mohamed Hosny ◽  
Mahmoud R. Asran ◽  
Farag A. Saeed
Keyword(s):  
Common Scab ◽  
Disease Susceptibility ◽  
Total Sugar ◽  
Streptomyces Scabies ◽  
Potato Tubers ◽  
Bacterial Diseases ◽  
Potato Plants ◽  
Streptomyces Scabiei ◽  
Pectin Substances

Streptomyces common scab is one of the most bacterial diseases that costs economic loses to potato plants. Streptomyces scabiei (Thaxter 1891) Lambert and Loria (syn. Streptomyces scabies) is the main causal agent of common scab in potato in the field. Eight potato cultivars namely, Diamont, Lady Rossete, Burna, Lady Bellford, Skenta, Flora, Brofent and Everest were tested for their susceptibility to common scab disease under greenhouse conditions. They varied to some extent in the degree of their susceptibility. Lady Rosette appeared to be the highest susceptible one followed by Burna, Everest, and Skenta. Lady Bellford, Diamont respectively, and Brofent showed intermediate disease severity. Flora cultivar exhibited the least degree of scab symptoms. The role of certain potato tubers constituents in the physiology of disease susceptibility was investigated (sugar contents, pectin substances and calcium contents), Lady Bellford cultivar contained the highest concentration of total sugar followed by Flora, Burna, and Everest but Skenta, Lady Rosette respectively and Diamont were approximately had equal in total sugar contents, while, Brofent cultivar contained the lowest content of total sugar. Skenta cultivar contained the highest concentration of pectin substances and calcium contents followed by Flora and Lady Bellford finally Burna cultivars respectively.

scholarly journals Recommendation for the conservation of the name Streptomyces scabies. Request for an Opinion

2007 ◽  
Vol 57 (10) ◽  
pp. 2447-2448 ◽  
Author(s):  
D. H. Lambert ◽  
R. Loria ◽  
D. P. Labeda ◽  
G. S. Saddler
Keyword(s):  
Common Scab ◽  
Streptomyces Scabies ◽  
General Recognition ◽  
Streptomyces Scabiei

The primary streptomycete inciting common scab of potato was first legitimately described by Thaxter in 1892 as ‘Oospora scabies’, preserving the spelling of an epithet in use since 1846. The name Streptomyces scabies, dating to 1948, was revived in 1989, but changed to Streptomyces scabiei in 1997 to follow grammatical convention. Considering the long-established use and general recognition of ‘scabies’, it is proposed that the original epithet be conserved.

scholarly journals Plasmid-Encoded Metallo-β-Lactamase (IMP-6) Conferring Resistance to Carbapenems, Especially Meropenem

2001 ◽  
Vol 45 (5) ◽  
pp. 1343-1348 ◽  
Author(s):  
Hisakazu Yano ◽  
Akio Kuga ◽  
Ryoichi Okamoto ◽  
Hidero Kitasato ◽  
Toshimitsu Kobayashi ◽  
...  
Keyword(s):  
Point Mutation ◽  
Antimicrobial Agents ◽  
Pcr Amplification ◽  
Penicillin G ◽  
Gene Encoding ◽  
Mature Enzyme ◽  
Dna Fragment ◽  
Lactamase Gene ◽  
Reduced Activity ◽  
Northern Japan

ABSTRACT In 1996, Serratia marcescens KU3838 was isolated from the urine of a patient with a urinary tract infection at a hospital in northern Japan and was found to contain the plasmid pKU501. Previously, we determined that pKU501 carries bla IMP and the genes for TEM-1-type β-lactamases as well as producing both types of β-lactamases (H. Yano, A. Kuga, K. Irinoda, R. Okamoto, T. Kobayashi, and M. Inoue, J. Antibiot. 52:1135–1139, 1999). pKU502 is a recombinant plasmid that contains a 1.5-kb DNA fragment, including the metallo-β-lactamase gene, and is obtained by PCR amplification of pKU501. The sequence of the metallo-β-lactamase gene in pKU502 was determined and revealed that this metallo-β-lactamase gene differed from the gene encoding IMP-1 by one point mutation, leading to one amino acid substitution: 640-A in the base sequence of the IMP-1 gene was replaced by G, and Ser-196 was replaced by Gly in the mature enzyme. This enzyme was designated IMP-6. The strains that produced IMP-6 were resistant to carbapenems. The MICs of panipenem and especially meropenem were higher than the MIC of imipenem for these strains. The k cat/Km value of IMP-6 was about sevenfold higher against meropenem than against imipenem, although the MIC of meropenem for KU1917, which produced IMP-1, was lower than that of imipenem, and the MIC of panipenem was equal to that of imipenem. These results support the hypothesis that IMP-6 has extended substrate profiles against carbapenems. However, the activity of IMP-6 was very low against penicillin G and piperacillin. These results suggest that IMP-6 acquired high activity against carbapenems, especially meropenem, via the point mutation but in the process lost activity against penicillins. Although IMP-6 has reduced activity against penicillins due to this point mutation, pKU501 confers resistance to a variety of antimicrobial agents because it also produces TEM-1-type enzyme.

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