Mehanizmi i značaj horizontalnog prijenosa gena kod mikroorganizama

undergraduate thesis

• Title (english): Mechanisms and significance of horizontal gene transfer in microorganisms
• Author: Elena Pirović
• Mentor: Sunčica Bosak (mentor)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2023-09-22, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Horizontalnim prijenosom gena prenosi se genska informacija između organizama koji
nisu u odnosu roditelj-potomak. Ovakav prijenos gena najzastupljeniji je među
mikroorganizmima. Postoje tri glavna mehanizma horizontalnog prijenosa gena između
mikroorganizama: konjugacija, transformacija i transdukcija. Konjugacija predstavlja prijenos
mobilnih genskih elemenata, najčešće plazmida, preko spolnog pilusa. Bakterije koje sadrže F
plazmid nazivaju se F+ bakterijama te su one donori plazmida, pretvarajući Fbakterije u F+. F
plazmid može se i ugraditi u kromosom domaćina, čime nastaju Hfr sojevi. Transformacija je unos
okolišne DNA u domaćina. Bakterije sposobne za primitak okolišne DNA nazivaju se
kompetentnim bakterijama. Transdukcija je fazima posredovan horizontalni prijenos gena.
Razlikuju se specijalizirana transdukcija, kod koje se prenose samo specifični geni, te
generalizirana transdukcija, kod koje je moguće prenijeti bilo koji gen. Horizontalni prijenos gena
mikroorganizmima omogućuje brzu prilagodbu na okolišne uvjete te je važan posrednik
prokariotske evolucije. Najbolji primjeri za ovo jesu proteorodopsin te rezistencija na antibiotike,
oboje važne adaptacije koje su široko rasprostranjene upravo zbog pozitivnog učinka na vijabilnost
jedinki koje ih posjeduju.

Abstract (english)

Horizontal gene transfer is the movement of genetic information other than by the
transmission of DNA from parent to offspring. This type of gene transfer is most prevalent among
microorganisms. There are three main mechanisms of horizontal gene transfer between
microorganisms: conjugation, transformation and transduction. Conjugation represents the transfer
of mobile genetic elements, usually plasmids, through the sex pilus. Bacteria containing the F
plasmid are called F+ bacteria and they are plasmid donors, converting F- bacteria into F+. The F
plasmid can also be incorporated into the host's chromosome, resulting in Hfr strains.
Transformation is the introduction of environmental DNA into the host. Bacteria capable of
receiving environmental DNA are called competent bacteria. Transduction is phage-mediated
horizontal gene transfer. There is a difference between specialized transduction, where only
specific genes are transferred, and generalized transduction, where any gene can be transferred.
Horizontal gene transfer enables microorganisms to quickly adapt to environmental conditions and
is an important mediator of prokaryotic evolution. The best examples of this are proteorhodopsin
and antibiotic resistance, both important adaptations that are widespread precisely because of the
positive effect on the viability of the individuals that possess them.

• Keywords: konjugacija; transformacija; transdukcija; proteorodopsin; antibiotici
• Keywords (english): conjugation; transformation; transduction; proteorhodopsin; antibiotics
• Language: croatian
• URN:NBN: urn:nbn:hr:217:740386
• Study programme: Title: Ecology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) biologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-09-28 08:59:01