Naslov
More than just hitchhikers: a survey of bacterial communities associated with diatoms originating from loggerhead sea turtles

Autori
Filek , Klara ; Chaerle , Peter ; Liesbeth , Lebbe ; Vyverman , Wim ; Willems , Anne ; Žižek , Marta ; Bosak , Sunčica

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, neobjavljeni rad, znanstveni

Skup
18th International Symposium on Microbial Ecology

Mjesto i datum
Lausanne, Švicarska, 14.08.2022. - 19.08.2022

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
phycosphere ; microbiome ; sea turtles

Sažetak
Diatoms and bacteria are the first colonizers of submerged surfaces (non-living and living), including the skin and carapace of sea turtles where they can form biofilms. Multiple studies point to the prevalence and ecological importance of diatom-bacteria interactions in phytoplankton ; however, little is known about diatom-bacteria associations in epizoic biofilms. This study aimed to investigate the bacterial communities associated with diatoms present on loggerhead sea turtles, some of which are exclusively epizoic. To investigate the diatom and bacterial communities of epizoic biofilms we employed a PCR- based metabarcoding approach combined with diatom/bacteria cultivation. We isolated diatoms from carapace and skin samples and established xenic monocultures. Diatom communities in source samples were surveyed via rbcL metabarcoding, while monoclonal cultures were identified based on morphology and rbcL gene sequencing. Bacteria within the diatom cultures were isolated and cultured for full 16S rRNA gene sequencing, while amplicon sequencing of the V4 region of the 16S rRNA gene enabled bacterial community characterisation within diatom monocultures and diatom source samples. The lack of representative sequences in rbcL database Diat.barcode made it difficult to detect understudied epizoic diatoms by metabarcoding surveys. Bacterial communities associated with diatom strains reflected their source sample based on bacterial taxa composition, and there are indications that similar diatom genera retain related bacterial taxa. Alcanivoracaceae, Marinobacteraceae, Phycisphaeraceae families were enriched in diatom cultures with readily culturable representatives. In conclusion, loggerhead sea turtles have been shown to be colonized by often understudied diatoms whose bacterial communities might reveal important diatom-bacteria associations in epizoic biofilms.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

Napomena
Diatoms and bacteria are the first colonizers of
submerged surfaces (non-living and living), including
the skin and carapace of sea turtles where they can form
biofilms. Multiple studies point to the prevalence and
ecological importance of diatom-bacteria interactions in
phytoplankton; however, little is known about diatom-
bacteria associations in epizoic biofilms. This study
aimed to investigate the bacterial communities
associated with diatoms present on loggerhead sea
turtles, some of which are exclusively epizoic.

To investigate the diatom and bacterial communities of
epizoic biofilms we employed a PCR-based metabarcoding
approach combined with diatom/bacteria cultivation. We
isolated diatoms from carapace and skin samples and
established xenic monocultures. Diatom communities in
source samples were surveyed via rbcL metabarcoding,
while monoclonal cultures were identified based on
morphology and rbcL gene sequencing. Bacteria within the
diatom cultures were isolated and cultured for full 16S
rRNA gene sequencing, while amplicon sequencing of the
V4 region of the 16S rRNA gene enabled bacterial
community characterisation within diatom monocultures
and diatom source samples.

The lack of representative sequences in rbcL database
Diat.barcode made it difficult to detect understudied
epizoic diatoms by metabarcoding surveys. Bacterial
communities associated with diatom strains reflected
their source sample based on bacterial taxa composition,
and there are indications that similar diatom genera
retain related bacterial taxa. Alcanivoracaceae,
Marinobacteraceae, Phycisphaeraceae families were
enriched in diatom cultures with readily culturable
representatives.

In conclusion, loggerhead sea turtles have been shown to
be colonized by often understudied diatoms whose
bacterial communities might reveal important diatom-
bacteria associations in epizoic biofilms.

POVEZANOST RADA