Campylobacter insulaenigrae Isolates from Northern Elephant Seals ( Mirounga angustirostris ) in California

Abstract

There are only two reports in the literature demonstrating the presence of Campylobacter spp. in marine mammals. One report describes the isolation of a new species, Campylobacter insulaenigrae sp. nov., from three harbor seals (Phoca vitulina) and a harbor porpoise (Phocoena phocoena) in Scotland, and the other describes the isolation of Campylobacter jejuni, Campylobacter lari, and an unknown Campylobacter species from northern elephant seals (Mirounga angustirostris) in California. In this study, 72 presumptive C. lari and unknown Campylobacter species strains were characterized using standard phenotypic methods, 16S rRNA PCR, and multilocus sequence typing (MLST). Phenotypic characterization of these isolates showed them to be variable in their ability to grow either at 42°C or on agar containing 1% glycine and in their sensitivity to nalidixic acid and cephalothin. Based on both 16S rRNA PCR and MLST, all but 1 of the 72 isolates were C. insulaenigrae, with one isolate being similar to but distinct from both Campylobacter upsaliensis and Campylobacter helveticus. Phylogenetic analysis identified two C. insulaenigrae clades: the primary clade, containing exclusively California strains, and a secondary clade, containing some California strains and all of the original Scottish strains. This study demonstrates the inability of phenotypic characterization to correctly identify all Campylobacter species and emphasizes the importance of molecular characterization via 16S rRNA sequence analysis or MLST for the identification of Campylobacter isolates from marine mammals.Campylobacter spp. are gram-negative, motile spiral rods that can be zoonotic pathogens (15). Many species of Campylobacter, such as C. jejuni and C. lari, are oxidase and catalase positive and grow in thermophilic, microaerophilic conditions (15). Campylobacter spp. can cause gastroenteritis in humans, primates, birds, dogs, cats, cattle, and swine, with symptoms including fever, abdominal cramping, and mild to bloody diarrhea (5,15,16). The presence of Campylobacter in saltwater typically indicates recent fecal contamination, because these bacteria are not able to replicate or survive for prolonged periods in surface water (10,18,19). Sources of Campylobacter spp. in the environment are sewage treatment plants, agricultural runoff, freshwater outflow, and wildlife (17,18).Reports of Campylobacter species isolated from marine mammals are rare: to date, there have been only two reports in the literature. Campylobacter insulaenigrae sp. nov. (hereafter termed C. insulaenigrae) was isolated from three harbor seals (Phoca vitulina) and a harbor porpoise (Phocoena phocoena) in Scotland; the role of this bacterium in disease is not known (3). The isolation of C. jejuni, C. lari, and an unknown Campylobacter species from juvenile northern elephant seals (Mirounga angustirostris) in California was also reported (23).

Atypical Dermatophilus Congolensis Infection in a Three-Year-Old Pony

“…11 Partial sequences of the rRNA gene showed the current isolate had 98% and 99% identity to this region in the D. congolensis type strain DSM 44180 in the forward (nucleotides 376-930 of accession no. AJ243918) and reverse (nucleotides 665-1224) directions, respectively.…”

Isolation and Characterization of Campylobacter spp. from Antarctic Fur Seals ( Arctocephalus gazella ) at Deception Island, Antarctica

“…The isolation of C. jejuni, C. lari, and an unknown Campylobacter species from juvenile northern elephant seals (Mirounga angustirostris) in California was also reported (22). Finally, 71 isolates of C. insulaenigrae and 1 isolate similar to but distinct from both Campylobacter upsaliensis and Campylobacter helveticus were isolated from northern elephant seals in California (23). In the South Georgia Archipelago, fecal swabs were taken from 206 Antarctic fur seal pups, but no isolates could be obtained (4).…”

“…In the case of C. insulaenigrae strains, MLST was performed following the protocol described by Stoddard et al (23). All amplicons were sequenced by the Sequencing Service of the Instituto de Salud Carlos III (Madrid, Spain).…”

“…insulaenigrae is a new Campylobacter species whose host range might be restricted to marine mammals (23). It could be hypothesized that C. insulaenigrae evolved from C. lari based on the presence of both species in sea lions and their sharing (23).…”

“…insulaenigrae is a new Campylobacter species whose host range might be restricted to marine mammals (23). It could be hypothesized that C. insulaenigrae evolved from C. lari based on the presence of both species in sea lions and their sharing (23). In addition, considering that C. insulaenigrae has not been isolated from seabirds or shellfish and the migration ranges of sea lions are generally not very large, Antarctic fur seals could have been initially infected with C. lari, and subsequently this species has evolved, adapting to mammals.…”