Komagataeibacter sp. nov. T5K1

ocetnokislinska bakterija, izolirana iz kvasovke Saccharomycodes ludwigii

Mateja Polc (Author), Janja Trček (Mentor)

Abstract

Ocetnokislinske bakterije so skupina mikroorganizmov, ki jih v naravi pogosto najdemo na substratih, bogatih s sladkorji, alkoholi in kislinami. Število opisanih rodov ocetnokislinskih bakterij je v zadnjih 30 letih iz prvotno dveh narastlo na 19. Med njimi je največje število vrst opisanih znotraj rodov Acetobacter, Gluconobacter, Gluconacetobacter in Komagataeibacter. V magistrskem delu smo iz kvasovke Saccharomycodes ludwigii T5K1 osamili ocetnokislinsko bakterijo Komagataeibacter sp. T5K1_A in jo nadalje okarakterizirali s preiskovanjem nukleotidnega zaporedja genov za 16S rRNA in medgenske regije 16S-23S rDNA. Odkrili smo, da je njen najbližji sorodnik vrsta Gluconacetobacter entanii; njuni sekvenci gena za 16S rRNA sta si podobni v 99 %, sekvenci medgenskih regij 16S-23S rDNA pa v 94 %. Glede na do sedaj poznane podatke o podobnosti teh DNA-regij med vrstami ocetnokislinskih bakterij smo domnevali, da bi sev Komagataeibacter sp. T5K1_A lahko bila nova vrsta ocetnokislinske bakterije. Odločili smo se, da naredimo natančno fenotipsko analizo in poiščemo fenotipske lastnosti, ki omogočajo razlikovanje seva Komagataeibacter sp. T5K1_A od njemu najbolj sorodnih vrst. Sev Komagataeibacter sp. T5K1_A je mogoče razlikovati od dveh filogenetsko najbolj sorodnih vrst Gluconacetobacter entanii in Komagataeibacter maltaceti po zmožnosti tvorbe 2-keto-D-glukonske kisline, uporabe sorbitola, D- manitola, D-glukonata in glicerola kot edinega vira ogljika za rast, fermentaciji D-manitola do kisline in še nekaterih drugih biokemijskih lastnostih. Sev Komagataeibacter sp. T5K1_A raste tudi pri višjih koncentracijah ocetne kisline ob prisotnosti 1 % in 3 % etanola v gojišču RAE, v primerjavi s tipskim sevom Komagataeibacter maltaceti. Sev Komagataeibacter sp. T5K1_A producira na gojišču RAE celulozo. Zaradi vseh teh lastnosti je sev Komagataeibacter sp. T5K1_A zelo verjetno nova vrsta ocetnokislinske bakterije. Za dokončno potrditev te hipoteze bo potrebno razlike seva Komagataeibacter sp. T5K1 od njemu najbolj sorodnih vrst potrditi še na nivoju celokupne DNA genomov. Sekvenciranje genoma seva Komagataeibacter sp. T5K1 in genomov njemu najbolj sorodnih vrst trenutno poteka v sodelovanjem z raziskovalno skupino iz Belgije.

Keywords

magistrska dela;ocetnokislinske bakterije;rod Komagataeibacter;industrijski bioprocesi;kis;16S rRNA;16S-23S rDNA;identifikacija;

Data

Language:	Slovenian
Year of publishing:	2017
Typology:	2.09 - Master's Thesis
Organization:	UM FNM - Faculty of Natural Sciences and Mathematics
Publisher:	[M. Polc]
UDC:	579(043.2)
COBISS:	23036936
Views:	1543
Downloads:	152
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Komagataeibacter sp. nov. T5K1: acetic acid bacterium isolated from the yeast Saccharomycodes ludwigii
Secondary abstract:	Acetic acid bacteria are microorganisms which are commonly found in sugary, acidic and alcoholic habitats. The number of described genera of acetic acid bacteria has increased in the last 30 years from two to 19. Most of the species are described in genera Acetobacter, Gluconobacter, Gluconacetobacter and Komagataeibacter. In this work, we isolated acetic acid bacterium Komagataeibacter sp. T5K1_A from yeast Saccharomycodes ludwigii T5K1. The comparative analysis of the 16S rRNA gene sequence and 16S- 23S rDNA gene internal transcribed spacer region revealed sequence similarities of 99 % and 94 %, respectively, between strain Komagataeibacter sp. T5K1_A and the type strain of the most closely related species Gluconacetobacter entanii. Based on the most current data of these DNA regions' similarities among acetic acid bacteria, we predicted that the strain Komagataeibacter sp. T5K1_A could represent a novel species. Therefore, we proceeded with basic phenotypic analyses. We found out that strain Komagataeibacter sp. T5K1_A can be differentiated from its closely related species, Gluconacetobacter entanii and Komagataeibacter maltaceti, by its ability to form 2-keto-D-gluconic acid, use sorbitol, D- mannitol, D-gluconate and glycerol as a sole carbon source, by forming acid from D-mannitol, and by some other biochemical features. Strain Komagataeibacter sp. T5K1_A can grow on medium with higher concentrations of acetic acid in the presence of 1 % and 3 % ethanol in comparison to the type strain of Komagataeibacter maltaceti and is capable of producing cellulose. For the final confirmation that the strain Komagataeibacter sp. T5K1_A is truly a novel species of acetic acid bacterium, the differentiation from its closest species has to be confirmed on the entire genome sequences. Sequencing of the Komagataeibacter sp. T5K1_A whole genome and its closest relatives is presently running in a collaboration with a research group from Belgium.
Secondary keywords:	master theses;acetic acid bacteria;genus Komagataeibacter;industrial bioprocesses;vinegar;16S rRNA;16S-23S rDNA;identification;
URN:	URN:SI:UM:
Type (COBISS):	Master's thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za naravoslovje in matematiko, Oddelek za biologijo
Pages:	IX f., 52 str.
ID:	9591169