Inhibicija uzročnika račje kuge, Aphanomyces astaci Schikora 1906, bakterijskim izolatima s kutikule rakova

master's thesis

• Title (english): Inhibition of crayfish plague pathogen, Aphanomyces astaci Schikora 1906, by bacterial isolates from crayfish exoskeleton
• Author: Lucija Vukšić
• Mentor: Ana Bielen (mentor)
• Committee member: Reno Hrašćan (predsjednik povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biology and Microbial Genetics); Zagreb
• Defense date and country: 2022-06-28, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Račja kuga, uzrokovana patogenom Aphanomyces astaci, ugrožava prirodne populacije slatkovodnih rakova te uzrokuje ekonomske gubitke u akvakulturi rakova. Cilj ovog rada bio je istražiti inhibicijski potencijal bakterijskih izolata s kutikule rakova prema rastu micelija patogena A. astaci. Analizom gena koji kodira za 16S rRNA identificirano je 145 bakterijskih izolata s kutikule signalnog, uskoškarog, riječnog, potočnog i bjelonogog raka. Neovisno o vrsti raka, najveći udio izolata bio je iz koljena Proteobacteria (66 %, uključujući najčešće rodove Pseudomonas i Aeromonas), zatim Bacteroidetes (18 %, s najčešćim rodom Flavobacterium), Firmicutes (13 %), Actinobacteria (2 %) i Cyanobacteria (1 %). Nadalje, provedeni su in vitro testovi inhibicije prema kojima su izolati razvrstani u inhibitore (13 %, najčešće iz rodova Pseudomonas i Aeromonas) i ne-inhibitore (87 %). Zaključno, rezultati ovog rada otvaraju mogućnost primjene bakterija kao ekološki prihvatljive metode kontrole patogena A. astaci u akvakulturi.

Abstract (english)

Crayfish plague, caused by the pathogen Aphanomyces astaci, threatens natural freshwater crayfish and causes economic losses in astaciculture. The aim of this study was to investigate the inhibitory potential of bacterial isolates from the crayfish exoskeleton against mycelial growth of A. astaci. A total of 145 bacterial isolates from the exoskeleton of signal crayfish, narrow-clawed crayfish, noble crayfish, stone crayfish and white-clawed crayfish were identified by 16S rRNA gene analysis. Regardless of the crayfish species, most isolates belonged to the phylum Proteobacteria (66 %, including the most common genera Pseudomonas and Aeromonas), followed by Bacteroidetes (18 %, most commonly the genus Flavobacterium), Firmicutes (13 %), Actinobacteria (2 %) and Cyanobacteria (1 %). In addition, in vitro inhibition tests were performed, according to which the isolates were classified as inhibitors (13 %, most frequently from the genera Pseudomonas and Aeromonas) or non-inhibitors (87 %). The results of this work open up the perspective of using bacteria as an environmentally acceptable method of controlling A. astaci in aquaculture.

• Keywords: deseteronožni rakovi; astacikultura; biokontrola; 16S rRNA; testovi inhibicije
• Keywords (english): decapod crayfish; biocontrol; bacterial isolates; 16S rRNA; plate inhibition assay
• Language: croatian
• URN:NBN: urn:nbn:hr:159:758161
• Study programme: Title: Molecular Biotechnology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka molekularne biotehnologije (magistar/magistra inženjer/inženjerka molekularne biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-06-29 11:51:30