A First Insight into the Gut Microbiota of the Sea Turtle Caretta caretta

Abdelrhman, Khaled Farag A.; Bacci, Giovanni; Mancusi, Cecilia; Mengoni, Alessio; Serena, Fabrizio; Ugolini, Alberto

doi:10.3389/fmicb.2016.01060

Cited by 56 publications

(73 citation statements)

References 24 publications

(27 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Relative abundance of the Firmicutes, however, was lower than expected in comparison with other studies of the reptilian gut microbiome [26,33,34]. Recent work by Abdelrhman et al, which to our knowledge is currently the only published culture-independent study to characterize gut microbial communities of live sea turtles, found much higher abundances of Firmicutes within captive loggerhead turtles [26].…”

Section: Discussionmentioning

confidence: 71%

“…Recent work by Abdelrhman et al, which to our knowledge is currently the only published culture-independent study to characterize gut microbial communities of live sea turtles, found much higher abundances of Firmicutes within captive loggerhead turtles [26]. One likely reason for this disparity is that the cloacal microbiome is simply different than the intestinal microbiome in reptiles, due to factors such as environmental influence and aerobic conditions.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of the juvenile green turtle (Chelonia mydas) microbiome throughout an ontogenetic shift from pelagic to neritic habitats

et al. 2017

View full text Add to dashboard Cite

The gut microbiome of herbivorous animals consists of organisms that efficiently digest the structural carbohydrates of ingested plant material. Green turtles (Chelonia mydas) provide an interesting model of change in these microbial communities because they undergo a pronounced shift from a surface-pelagic distribution and omnivorous diet to a neritic distribution and herbivorous diet. As an alternative to direct sampling of the gut, we investigated the cloacal microbiomes of juvenile green turtles before and after recruitment to neritic waters to observe any changes in their microbial community structure. Cloacal swabs were taken from individual turtles for analysis of the 16S rRNA gene sequences using Illumina sequencing. One fecal sample was also obtained, allowing for a preliminary comparison with the bacterial community of the cloaca. We found significant variation in the juvenile green turtle bacterial communities between pelagic and neritic habitats, suggesting that environmental and dietary factors support different bacterial communities in green turtles from these habitats. This is the first study to characterize the cloacal microbiome of green turtles in the context of their ontogenetic shifts, which could provide valuable insight into the origins of their gut bacteria and how the microbial community supports their shift to herbivory.

show abstract

Section: Discussionmentioning

confidence: 71%

Section: Discussionmentioning

confidence: 99%

Characterization of the juvenile green turtle (Chelonia mydas) microbiome throughout an ontogenetic shift from pelagic to neritic habitats

et al. 2017

View full text Add to dashboard Cite

show abstract

“…In this study, we report for the first time the isolation and the antibiotic resistance profile of Gram-negative bacteria, from wild free-living loggerhead sea turtles in the Mediterranean Sea. A few studies have previously described the microbiota associated with Caretta caretta turtles [30][31][32], but the analysis was carried out on fecal samples of animals which experienced from few to many days in specialized centers [30][31][32], or on the intestinal samples of dead animals [30]. These studies revealed the gut microbial composition of loggerhead sea turtles by using the metagenomics approach, but results could be biased by the health conditions of the animals, by conditions, treatments or therapies in the recovery centers.…”

Section: Discussionmentioning

confidence: 99%

“…The latter were the sea turtles with a problem (hook, plastic presence, gastrointestinal occlusion, collision with a boat) that needed a recovery period. A significant correlation was found among the different body measurements recorded To date, a few studies investigated the microbial community associated with Caretta caretta by using culture-dependent methods [9,10,[27][28][29] or metagenomic analysis [30][31][32], and even fewer studies were carried out on the antibiotic resistance of isolates [9,10,13,28]. All the latter studies collected samples from animals that needed to be recovered for several reasons (traumas, ingestion of fishing hooks, parasitosis, respiratory disorders) [9,10,13,28], or found dead along the seacoast [13].…”

Section: Loggerhead Turtles' Size and Health Statusmentioning

confidence: 99%

Antibiotic Resistance of Gram-Negative Bacteria from Wild Captured Loggerhead Sea Turtles

Blasi¹,

Migliore

Mattei³

et al. 2020

Antibiotics

View full text Add to dashboard Cite

Sea turtles have been proposed as health indicators of marine habitats and carriers of antibiotic-resistant bacterial strains, for their longevity and migratory lifestyle. Up to now, a few studies evaluated the antibacterial resistant flora of Mediterranean loggerhead sea turtles (Caretta caretta) and most of them were carried out on stranded or recovered animals. In this study, the isolation and the antibiotic resistance profile of 90 Gram negative bacteria from cloacal swabs of 33 Mediterranean wild captured loggerhead sea turtles are described. Among sea turtles found in their foraging sites, 23 were in good health and 10 needed recovery for different health problems (hereafter named weak). Isolated cloacal bacteria belonged mainly to Enterobacteriaceae (59%), Shewanellaceae (31%) and Vibrionaceae families (5%). Although slight differences in the bacterial composition, healthy and weak sea turtles shared antibiotic-resistant strains. In total, 74 strains were endowed with one or multi resistance (up to five different drugs) phenotypes, mainly towards ampicillin (~70%) or sulfamethoxazole/trimethoprim (more than 30%). Hence, our results confirmed the presence of antibiotic-resistant strains also in healthy marine animals and the role of the loggerhead sea turtles in spreading antibiotic-resistant bacteria.

show abstract

“…Metagenomic analyses have contributed to gain a better insight on taxonomic composition and functions of the gut microbiota of various species, including non-model organisms, such as sea turtles (10). Gut microbiota may confer adaptability to herbivorous tortoises such as G. berlandieri and C. sulcata naturally exposed to low nitrogen-content diets.…”

Section: Introductionmentioning

confidence: 99%

Nitrogen-fixing Klebsiella variicola in feces from herbivorous tortoises

Montes-Grajales

Jiménez

Rogel

et al. 2019

Preprint

View full text Add to dashboard Cite

2 25 Abstract 26 Animals feeding on plants (herbivorous) may have nutritional deficiencies and 27 use bacterial nitrogen fixation in guts to compensate unbalanced diets with high carbon 28 and low nitrogen. Using the acetylene reduction assay we searched for nitrogen fixation 29 in the feces from several herbivorous animals in captivity. We detected acetylene 30 reduction in feces from two African spurred tortoises, Centrochelys sulcata and in feces 31 from six Gopherus berlandieri tortoises and isolated nitrogen-fixing klebsiellas from 32 them. Additionally, we performed a gut metagenomic study with Illumina sequencing 33 from a healthy Mexican G. berlandieri tortoise, and the nif genes identified in the feces 34 microbiome matched those from Klebsiella variicola. Fecal bacterial composition from 35 tortoises was similar to that reported from other reptilian guts. 36 3 37 Introduction 38 Nitrogen fixation is a unique biochemical process carried out by nitrogenases 39 encoded by nif genes, which are found in only a few prokaryotes (1). Nitrogen fixation 40 is energetically expensive and nitrogen-fixing bacteria are in many cases minor 41 components of the microbial community that nevertheless provide a valuable ecological 42 service (2). Nitrogen-fixing bacteria are called diazotrophs (3). 43 When associated with nitrogen-fixing bacteria, insects or plants may inhabit in 44 nitrogen poor conditions. Termites contain nitrogen-fixing bacteria in their guts that 45 allow them to grow in wood, similarly wood eating beetles contain nitrogen-fixing 46 bacteria (4). Nitrogen fixation by Klebsiella variicola occurs in the fungal garden of 47 ants (5). A novel betaproteobacterium capable of fixing nitrogen is a recently described 48 symbiont that is transmitted by eggs of carmine cochineals which feed on cacti as the 49 Gopherus berlandieri tortoise does (6). Cacti have high sugar content and are nitrogen 50 poor, conditions that would be favorable for nitrogen fixation in animals that use cacti 51 for food, such as the carmine cochineal or the G. berlandieri tortoise. 52 G. berlandieri, is distributed from North Mexico (states of Coahuila, Nuevo 53 Leon and Tamaulipas) to South-central Texas in United States (7). This species 54 generally maintains restricted mobility by living for prolonged times in the same 55 burrow (8) and its diet is mainly composed of grasses, weeds and cacti. On the other 56 hand, the African spurred tortoise, Centrochelys sulcata, which is also vegetarian, lives 57 in West Africa (9). 58 Metagenomic analyses have contributed to gain a better insight on taxonomic 59 composition and functions of the gut microbiota of various species, including non-60 model organisms, such as sea turtles (10). Gut microbiota may confer adaptability to 61 herbivorous tortoises such as G. berlandieri and C. sulcata naturally exposed to low 4 62 nitrogen-content diets. The aim of this research was to identify nitrogen-fixing species 63 in the gut microbiota of G. berlandieri and C. sulcata. In addition we present one G...

show abstract

A First Insight into the Gut Microbiota of the Sea Turtle Caretta caretta

Cited by 56 publications

References 24 publications

Characterization of the juvenile green turtle (Chelonia mydas) microbiome throughout an ontogenetic shift from pelagic to neritic habitats

Characterization of the juvenile green turtle (Chelonia mydas) microbiome throughout an ontogenetic shift from pelagic to neritic habitats

Antibiotic Resistance of Gram-Negative Bacteria from Wild Captured Loggerhead Sea Turtles

Nitrogen-fixing Klebsiella variicola in feces from herbivorous tortoises

Contact Info

Product

Resources

About