Alloiococcus

Abstract: Alloiococcus otitidis and Turicella otitidis are common bacteria of the human ear. They have frequently been isolated from the middle ear of children with otitis media (OM), though their potential role in this disease remains unclear and confounded due to their presence as commensal inhabitants of the external auditory canal. In this review, we summarize the current literature on these organisms with an emphasis on their role in OM. Much of the literature focuses on the presence and abundance of these organisms, and little work has been done to explore their activity in the middle ear. We find there is currently insufficient evidence available to determine whether these organisms are pathogens, commensals or contribute indirectly to the pathogenesis of OM. However, building on the knowledge currently available, we suggest future approaches aimed at providing stronger evidence to determine whether A. otitidis and T. otitidis are involved in the pathogenesis of OM. Such evidence will increase our understanding of the microbial risk factors contributing to OM and may lead to novel treatment approaches for severe and recurrent disease.

Abstract: The growth of Alloiococcus otitis under different atmospheres and nutritional conditions was studied. The growth rates of 25 strains of gram-positive cocci representing five genera on heart infusion agar plates containing 5% rabbit blood and on brucella agar plates with and without sheep blood under aerobic, increased CO2, and anaerobic atmospheres were compared. Eight strains of alloiococci plated on heart infusion agar with rabbit blood and on brucella sheep blood agar grew under aerobic and candle jar atmospheres. Two of these strains showed poor anaerobic growth after 7 days. Strains of Aerococcus viridans, Aerococcus urinae, Helcococci kunzi, Dolosigranulum pigrum, Gemella haemolysans, and Gemella morbillorum grew well under all three atmospheres and on the three types of media and in thioglycolate broth. These results confirm all the aerobic atmospheric requirements for Alloiococcus strains and show that aerobic growth characteristics help distinguish the alloiococci from the other gram-positive cocci that are facultatively anaerobic.

Abstract: Objective To investigate the microbiota of the healthy external auditory canal (EAC) culture-independently and to evaluate the usefulness of the swabbing method in collecting EAC microbiota samples. Study design Cohort study. Patients Fifty healthy asymptomatic working-age volunteers. Intervention Samples were harvested with DNA-free swabs from the volunteers' EACs. Main outcome measures Amplicon sequencing of the 16S rRNA gene was used to characterize the microbial communities in the samples. Results The swabbing method is feasible for EAC microbiota sample collection. The analyzed 41 samples came from 27 female and 14 male subjects; 4 samples were excluded due to recent antimicrobial treatment and 5 because of low sequence count or suspected contaminant microbes. The four most frequent amplicon sequence variants in the microbiota data were Staphylococcus auricularis, Propionibacterium acnes, Alloiococcus otitis, and Turicella otitidis. Typically, the dominant amplicon sequence variant in a sample was one of the most frequent bacteria, but there were also subjects where the dominant species was not among the most frequent ones. The genus Alloiococcus was least common in females who reported cleaning their ears. Subjects with a high relative abundance of Alloiococcus typically had a low abundance of Staphylococcus, which may be a sign of the two being competing members of the microbial community. Conclusions The most common bacteria in the microbiome of the healthy EAC were Staphylococcus auricularis, Propionibacterium acnes, Alloiococcus otitis, and Turicella otitidis. The EAC microbiota seems more diverse and individualized than previously thought. Also, ear cleaning habits seem to alter the EAC microbiome.

Abstract: Carnobacteriaceae, a family of the order Lactobacillales, within the phylum Firmicutes, embraces the genera Carnobacterium, Alkalibacterium, Allofustis, Alloiococcus, Atopobacter, Atopococcus, Atopostipes, Bavariicoccus, Desemzia, Dolosigranulum, Granulicatella, Isobaculum, Jeotgalibaca, Lacticigenium, Marinilactibacillus, Pisciglobus, and Trichococcus. Circumscribed mainly on the basis of 16S rRNA gene sequence analysis and defined by a wide range of morphological and chemotaxonomic properties, such as polar lipids, fatty acids, amino acids of peptidoglycan, and whole-cell sugars which are used for the delineation of genera and species. Members of the family are mainly found associated with food products, human, and cold environmental sources.