Production of antifungal N-acetyl-β-glucosaminidase chitinolytic enzyme using shrimp byproducts

Genome mining of pigmented Pseudoalteromonas has revealed a large potential for the production of bioactive compounds and hydrolytic enzymes. The purpose of the present study was to explore this bioactivity potential in a potent antibiotic and enzyme producer, Pseudoalteromonas rubra strain S4059. Proteomic analyses (data are available via ProteomeXchange with identifier PXD023249) indicated that a highly efficient chitin degradation machinery was present in the red-pigmented P. rubra S4059 when grown on chitin. Four GH18 chitinases and two GH20 hexosaminidases were significantly upregulated under these conditions. GH19 chitinases, which are not common in bacteria, are consistently found in pigmented Pseudoalteromonas, and in S4059, GH19 was only detected when the bacterium was grown on chitin. To explore the possible role of GH19 in pigmented Pseudoalteromonas, we developed a protocol for genetic manipulation of S4059 and deleted the GH19 chitinase, and compared phenotypes of the mutant and wild type. However, none of the chitin degrading ability, secondary metabolite profile, or biofilm-forming capacity was affected by GH19 deletion. In conclusion, we developed a genetic manipulation protocol that can be used to unravel the bioactive potential of pigmented pseudoalteromonads. An efficient chitinolytic enzyme cocktail was identified in S4059, suggesting that this strain could be a candidate with industrial potential.

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Purification and characterization of an exochitinase from Bacillus thuringiensis subsp. aizawai and its action against phytopathogenic fungi

Canadian Journal of Microbiology ◽

10.1139/w06-019 ◽

2006 ◽

Vol 52 (7) ◽

pp. 651-657 ◽

Cited By ~ 49

Author(s):

Luis Morales de la Vega ◽

J Eleazar Barboza-Corona ◽

Maria G Aguilar-Uscanga ◽

Mario Ramírez-Lepe

Keyword(s):

Bacillus Thuringiensis ◽

Sodium Dodecyl ◽

Sclerotium Rolfsii ◽

Phytopathogenic Fungi ◽

Purification And Characterization ◽

Chitinolytic Enzyme ◽

Bacillus Thuringiensis Subsp ◽

Sds Page ◽

Fusarium Sp

A chitinolytic enzyme from Bacillus thuringiensis subsp. aizawai has been purified and its molecular mass was estimated ca. 66 kDa by sodium dodecyl sulfate – polyacryamide gel electrophoresis (SDS–PAGE). The enzyme was able to hydrolyze chitin to chitobiosides but not carboxymethylcellulose, cellulose, pullulan, and laminarin. Optimal pH and temperature were detected at 6 and 50 °C, respectively. Stability, in the absence of substrate, was observed at temperatures less than 60 °C and pH between 5 and 8. Enzyme activity was significantly inhibited by K+ and EDTA and completely inhibited by Hg2+. Purified chitinase showed lytic activity against cell walls from six phytopathogenic fungi and inhibited the mycelial growth of both Fusarium sp. and Sclerotium rolfsii. The biocontrol efficacy of the enzyme was tested in the protection of bean seeds infested with six phytopathogenic fungi.Key words: chitinase, Bacillus thuringiensis, purification, phytopathogenic fungi.

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Aktivitas Bakteri Kitinolitik dari Cangkang Perna viridis sebagai Antifungi Phytophthora palmivora Penyebab Penyakit Busuk Buah Kakao (Theobroma cacao L.)

bionature ◽

10.35580/bionature.v18i2.6139 ◽

2018 ◽

Vol 18 (2) ◽

Author(s):

Ulfia Nurul Khikmah ◽

Muhson Isroni Isroni ◽

Anisa Maulidiya

Keyword(s):

Enzyme Activity ◽

Phytophthora Palmivora ◽

Perna Viridis ◽

Bacterial Isolates ◽

Chitinolytic Enzyme ◽

Chitinolytic Bacteria ◽

Agriculture Sector ◽

Rot Disease ◽

Bacterial Characterization ◽

Physiological Characters

Abstract. The emphasis on the growth of Phytophthora palmivora was important in order to reduce Pod Rot Disease of cacao (Theobrorna cacao L.) which could harm agriculture sector. Some bacteria had chitinolytic enzyme activity that is potentially used as an antifungal against Phytophthora palmivora, because the cell wall of the fungi composed of chitin. The purpose of this research was to know chitinolytic bacteria from Perna viridis shell which had higher activity of chitinase enzyme, the amount of chitinase enzyme activity of each selected isolate, and to know the effect of chitinolytic bacterial isolates from Perna viridis shell to reduce the growth of Phytophthora palmivora. The bacteria were isolated from Perna viridis shell at Depok Beach, Kretek, Bantul, Yogyakarta. This research was an explorative research which include bacterial characterization and experimental research which include antagonistic test of chitinolytic bacteria against Phytophthora palmivora. The chitinolytic bacteria was isolated using selective chitin agar medium by pour plate method and then screening the isolates that had chitinase enzyme activity by measuring the enzyme activity of each bacterial isolates by spectrophotometric method. Selected bacterial isolates were characterized by macroscopic, microscopic and physiological characters. The bacteria that had been selected tested for their ability to reduce the growth of Phytophthora palmivora by Kirby Bauer modification method. The result showed that there were 10 isolates that had chitinase enzyme activity which two selected isolates had the higher chitinase enzyme activity. There were 7D and 6B isolates. The isolate 7D had 1,258 u/ml chitinase enzyme activity and isolate 6B had 1,212 u/ml chitinase enzyme activity. The result of chitinolytic bacterial antagonist test on Phytophthora palmivora growth showed that both bacterial isolates were potential to antifungal Phytophthora palmivora and showed a real effect in inhibiting the growth of Phytophthora palmivora with significance value < 0,05.Keywords: Chitinolytic Bacteria, Perna viridis, Phytophthora palmivora

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