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A gram-stain-positive, facultatively anaerobic, non-spore-forming, catalase-negative, coccoid-shaped bacterial strain, designated BV2(T), was isolated from the vaginal mucosa of a beef cow in Japan. Phylogenetic analysis showed that the isolate shared high 16S rRNA gene sequence similarity (92.9 %) with Aerococcus suis 1821/02(T) and low similarity (<92.7 %) with any other recognized species of the genus Aerococcus. The DNA G+C content was 44.7 mol%, which is within the range observed among species of the genus Aerococcus (37.5-48.4 mol%). The major cellular fatty acid was C18 : 1ω9c, similar to other type strains of species of the genus Aerococcus. The results of genotypic, phenotypic and chemotaxonomic analyses as well as the low degree of DNA-DNA relatedness with all recognized members of the genus Aerococcus indicate that strain BV2(T) represents a novel species of the genus Aerococcus, for which the name Aerococcus vaginalis sp. nov. is proposed. The type strain is BV2(T) ( = JCM 19163(T) = DSM 27293(T)). Emended descriptions of Aerococcus suis, Aerococcus viridans, Aerococcus urinaeequi, Aerococcus urinaehominis, Aerococcus urinae, Aerococcus christensenii and Aerococcus sanguinicola are also presented.

Aerococcus is a genus that comprises seven species, of which Aerococcus urinae, and Aerococcus sanguinicola are emerging human pathogens. Aerococci are gram positive cocci that are easily misidentified as streptococci or staphylococci, and thus the incidence of aerococcal infections has been underestimated. With the introduction of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) clinical microbiologists now have access to a rapid and accurate method to identify aerococci. A. urinae and A. sanguinicola are isolated in a small proportion of urinary specimens in many laboratories and many patients with bacteriuria with aerococci have symptoms of urinary tract infection (UTI). A. urinae, and also A. sanguinicola, cause invasive infections including infective endocarditis (IE) with many reported fatalities. Especially older men with urinary tract abnormalities are at risk for bacteraemia with A. urinae but the prognosis of bacteraemia without IE is favourable. Penicillin is appropriate for treatment of invasive infections and in IE, addition of an aminoglycoside should be considered. Treatment of UTI with aerococci is complicated by uncertainty about the effect of trimethoprim-sulphametoxazole and fluoroquinolones on aerococci. This review will discuss identification of Aerococcus spp., antibiotic resistance, the clinical presentation and management of aerococcal infections as well as the virulence mechanisms of these bacteria., (Copyright © 2012 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

Conventional methods for the identification of human-pathogenic aerococci to the species level are not reliable. We show that matrix-assisted laser desorption ionization-time of flight mass spectrometry correctly identifies aerococci to the species level and that it can be used to identify aerococci with high specificity in the diagnostic clinical microbiology laboratory.

This is the first transcriptomic study focusing on immunity in the commercially valuable American lobster (Homarus americanus). We have conducted an in vivo infection trial using the Gram-positive bacterium Aerococcus viridans var. homari to determine how H. americanus responds to this naturally occurring lethal-pathogen. A novel H. americanus microarray was used to measure the transcriptomic changes occurring in over 14,000 genes in the lobster hepatopancreas. Hundreds of new immune genes and isoforms were identified and measured for the first time in this species, and our findings highlight 148 genes of interest involved in H. americanus pathogen response. We verified our microarray results using RT-qPCR on three anti-lipopolysaccharide (ALFHa-1, ALFHa-2, ALFHa-4), a thioredoxin, acute phase serum amyloid protein A, hexokinase and two trypsin genes. RT-qPCR and microarray findings show close agreement and highlight the significant increase in gene expression in many lobster immune genes during A. viridans infection. Differential expression of the ALFHa isoforms may indicate that the H. americanus immune response can be tailored to the class of pathogen causing disease., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Gaffkaemia, caused by Aerococcus viridans var. homari, causes fatal infections in Homarus spp. (clawed lobsters). Despite its high economic significance to the lobster fisheries in the USA and northern Europe, data on its prevalence in captured and wild populations, particularly in Europe, is scarce. Following an outbreak of gaffkaemia in a European lobster holding facility in South Wales (UK), a base-line survey was conducted for gaffkaemia in wild populations of European lobster Homarus gammarus around the coast of England and Wales. In addition, isolates recovered from the original outbreak and the survey were typed using pulsed-field gel electrophoresis (PFGE) and compared with previously characterised isolates from the USA, UK and Canada. Locally caught H. gammarus were sampled at 30 sites from around the coast of England and Wales between March 2006 and October 2008. Results confirmed that the prevalence of gaffkaemia in populations of H. gammarus was low, with only 9 positive isolates recovered from 952 samples examined. PFGE analysis showed that the isolates from the outbreak investigation shared the same pulsotype as A. viridans var. homari isolates from the USA, Norway and Canada, as well as an isolate (NCIMB 1119) reportedly recovered from an outbreak of European lobsters in England in the 1960s. This confirms earlier studies that suggest virulent strains of A. viridans var. homari show very limited geographical or temporal genetic variation and were introduced into the UK with American lobsters H. americanus.

There is mounting evidence that bacteria originating from pigs degrade the environment of the pig shed and adversely affect the health of the animals and the pig-shed workers. α-haemolytic cocci (AHC) occur in pig-shed environments, but are regarded as commensals. Ammonia is also a component of the pig-shed environment, and is known to damage upper respiratory tract epithelia. The aim of this study was to determine whether polluted air in pig sheds adversely affected performance indicators in pigs. Modelling revealed a direct effect of AHC on voluntary feed intake and hence AHC are not commensal. No direct effect of ammonia on the pigs was detected, but the combination of AHC and ammonia stimulated the immune system in a progressive manner, and there were direct effects of immune stimulation on food intake and growth resulting in poorer feed-conversion efficiency, even though the effects remained subclinical. The authors conclude that exposure of the respiratory epithelia of pigs to viable AHC in the presence of ammonia redirects nutrients away from production and towards the immune system, explaining the impact of poor pig-shed hygiene on production parameters.

Aerococcus viridans is a catalase-negative Gram-positive bacterium and has been described as an airborne organism widely distributed in the hospital environment or in clinical specimens. We isolated A. viridans strain LL1 from indoor dust samples collected by a patient. Here, we prepared a genome sequence for this strain consisting of 31 contigs totaling 1,994,039 bases and a GC content of 39.42%.

Aerococcus urinae is a Gram-positive bacterium that can cause invasive infection, including infectious endocarditis (IE), mainly in older men. A. urinae is often misclassified in routine diagnostic laboratories. Through searches in the laboratory databases we identify 16 isolates of A. urinae causing bacteraemia during a 6-year period in southern Sweden, indicating that bacteraemia with A. urinae occurs in at least three cases per million inhabitants per year. The identity of isolates was confirmed by sequencing of the 16S rRNA genes and antibiotic susceptibility testing identified two ciprofloxacin-resistant isolates. A. urinae was the only significant pathogen isolated in all cases. Fifteen of the 16 patients were male, 15/16 were more than 70 years old, and 12/16 had underlying urological conditions. Though a urinary tract focus was suspected in the majority of cases, the bacterium was rarely found in urinary samples. Nine patients fulfilled the criteria for severe sepsis and an additional four fulfilled the criteria for sepsis. Only one fatality was recorded. Patients were treated mainly with beta-lactam antibiotics but fluoroquinolones and clindamycin were also used. Three cases of IE were diagnosed and these were complicated by spondylodiscitis in one case and by septic embolization to the brain in one case. An increased awareness of A. urinae is crucial to establishing its role as an important pathogen in older men with urinary tract disease., (© 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.)

Aerococcus viridans is a rare human pathogen that occasionally causes endocarditis. Most of the reported cases of endocarditis have been treated with penicillin. Here we describe a patient who was allergic to penicillin and was successfully treated with cefotaxime., (Copyright © 2011. Published by Elsevier B.V.)

Aerococcus urinae has been described as resistant to trimethoprim-sulfamethoxazole (SXT), but the test medium may affect this observation. Twenty-seven clinical isolates of A. urinae tested susceptible to SXT in cation-adjusted Mueller-Hinton broth (CAMHB) plus lysed horse blood and resistant in CAMHB plus lysed sheep blood.

A retrospective chart review was performed on 92 patients from whom 118 isolates of Aerococcus sanguinicola (n = 52) or Aerococcus urinae (n = 66) were obtained from urine cultures between October 2007 and June 2008 to assess clinical presentation and antimicrobial susceptibilities. The mean patient age was 82 (range 24-101) years. The majority was female (76% and 87% for A. sanguinicola and A. urinae, respectively) and institutionalized (61% and 60%, respectively). The majority of male patients had underlying prostatic disease (55% and 63%, respectively). Thirty-one of 46 patients with A. sanguinicola and 45 of 57 patients with A. urinae isolated from the urine had a clinical diagnosis of urinary tract infection. One subject had A. sanguinicola isolated from blood cultures. A. sanguinicola and A. urinae had low ceftriaxone, penicillin, and vancomycin MICs. MICs to erythromycin and levofloxacin were ≥0.5 and >4 μg/mL in 41% and 78% of A. sanguinicola and 17% and 23% of A. urinae isolates, respectively. In conclusion, A. sanguinicola and A. urinae are not infrequent causes of urinary tract infection and most A. sanguinicola isolates have elevated MICs to levofloxacin., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Aerococcus viridans is not a common pathogen, and endocarditis due to A. viridans is very rare. A 44-year-old woman with persistent atrial fibrillation and rheumatic valvular heart disease was admitted with fever, sweating, weakness, and progressive shortness of breath. Transthoracic echocardiography (TTE) demonstrated a 8x9-mm vegetation attached to the right coronary cusp of the aortic valve, causing aortic obstruction. Blood cultures yielded A. viridans susceptible to penicillin. Despite optimal antibiotherapy, subsequent TTE controls revealed enlargement of the vegetation, reaching a size of 21x10 mm, and an increasing gradient across the aortic valve. The patient underwent successful aortic and mitral valve replacement and was stable in the postoperative period without any problem. This represents the first reported case of A. viridans endocarditis in which the size and location of vegetation caused obstruction to blood flow, indicating surgery.

Culturable bacteria were isolated from seeds, embryos and contaminated in vitro cultures of ash (Fraxinus excelsior L., F. ornus L. and F. angustifolia L.) and were identified using morphological and molecular analyses. Fourteen morphologically distinct isolates were recovered from seeds of Fraxinus spp. 16S rDNA sequencing categorised these isolates into ten separate genera. Three strains isolated from contaminated in vitro cultures, Pantoea agglomerans, Staphylococcus succinus and Aerococcus viridans, were used for comparative analysis with isolates from seeds. Antibiotic sensitivity testing of the isolated contaminants, including phytotoxicity of antibiotics on in vitro cultures of ash, was also investigated. Phytotoxic effects on explants immersed in ampicillin or cultured on medium containing ampicillin were negligible, however tetracycline, either alone or in combination with other antibiotics, had phytotoxic effects. We conclude that ampicillin is a suitable antibiotic to limit the growth of contaminating bacteria during the in vitro culture of ash., (© 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.)

The American lobster fishery is a significant economic driver in coastal communities of North America. Increasingly, the impacts of infectious disease are recognized as important components and factors in the population ecology and subsequent management of the lobster fishery. Both environmental and anthropogenic factors impact marine diseases. The review herein highlights aspects of several important bacterial, fungal and protistan diseases, including gaffkemia, shell disease, vibriosis, disease caused by species of Lagenidium, Haliphthoros and Fusarium, paramoebiasis and Bumper Car disease. As the global environment continues to change, these diseases could more severely affect both wild caught and impounded lobsters., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Today's large-scale poultry production with densely stocked and enclosed production buildings is often accompanied by very high concentrations of airborne microorganisms leading to a clear health hazard for employees working in such environments. Depending on the expected exposure to microorganisms, work has to be performed under occupational safety conditions. In this study, turkey houses bioaerosols were investigated by cultivation-based and molecular methods in parallel to determine the concentrations and the composition of bacterial community. Results obtained with the molecular approach showed clearly its applicability for qualitative exposure measurements. With both, cultivation-based and molecular methods species of microorganism with a potential health risk for employees (Acinetobacter johnsonii, Aerococcus viridans, Pantoea agglomerans, and Shigella flexneri) were identified. These results underline the necessity of adequate protection measures, including the recommendation to wear breathing masks during work in poultry houses.

Aerococcus viridans is a catalase-negative gram-positive bacterium rarely found as human pathogen. Some cases of urinary tract infection (UTI) have been described in immunocompromised adults. In this article we describe a UTI case caused by this agent in a child with severe obstructive uropathy, clinically presented with secondary pseudohypoaldosteronism (SPHA). Although A. viridans is rarely associated with child infection, it can be responsible for life threatening conditions/ situations. To our knowledge, A. viridans UTI has never been reported in pediatric patients.

Species belonging to the Aerococcus genus are isolated from the urine and blood of elderly patients suffering from urinary tract infections (UTIs). However, the clinical significance, phenotypic features and antimicrobial susceptibilities of these underestimated and/or misidentified species remain unclear. From March 2006 to November 2008, among 350 non-enterococcal Streptococcaceae species isolated from urinary specimens, 30 (8.6%) Aerococcus spp. strains were recovered. All strains were characterized using a phenotypic approach (API 20 STREP, ID 32 STREP and VITEK 2 systems), 16S rRNA gene sequencing, and susceptibility to antimicrobial agents commonly used in UTIs. The average age of patients was 73 y and most of them presented with a predisposing urological disease (31%) and/or a systemic underlying condition (48%). All isolates were identified to the species level using the molecular tool (Aerococcus urinae, n = 20; Aerococcus sanguinicola, n = 8; Aerococcus viridans, n = 2), whereas the phenotypic methods were frequently unreliable. All aerococcal isolates were susceptible to amoxicillin, vancomycin, and teicoplanin and showed a low-level resistance to gentamicin. Fluoroquinolones, co-trimoxazole, and fosfomycin exhibited a variable activity. Most A. urinae isolates were resistant to co-trimoxazole and susceptible to fosfomycin, whereas all A. sanguinicola isolates were resistant to fosfomycin and susceptible to co-trimoxazole.

Aerococcus urinae is a pathogen that rarely causes severe or fatal infections. We describe four cases of severe A. urinae bloodstream infections. All patients had underlying urologic conditions. Urine cultures, however, were negative.

Aerococcus viridans is a gram-positive, catalase and oxidase negative, microaerophylic and non-motile coccus which is rarely associated with human infections such as endocarditis, meningitis, artritis and bacteremia. We report a case of bacteremia due to A. viridans in a 61-years-old man with malignant gall bladder neoplasm. The patient underwent a surgical operation and on the 5th day of operation he had severe abdominal pain, vomiting, high fever and discharge from operation site. He was transferred to intensive care unit and blood cultures were obtained. Piperacillin-tazobactam was initiated as empirical therapy. Blood cultures performed in Bactec system (Becton Dickinson, USA) yielded catalase negative, gram-positive cocci in tetrads. The isolate was pyrrolidonyl aminopeptidase (PYR) positive and produced alfa-hemolysis on sheep blood agar. These cocci were identified as A. viridans by Vitek 2 Compact System (BioMerieux, France) and identification was confirmed by using mini API System (BioMerieux, France). Antibiotic susceptibility testing performed with Kirby-Bauer disk diffusion method revealed that the isolate was susceptible to trimethoprim-sulfamethoxazole, tigecycline and vancomycin and resistant to penicillin, ampicillin, piperacillin-tazobactam, ceftriaxone, erythromycin, clindamycin and amikacin. The patient was successfully treated with vancomycin (2 x 1 g/day) and completely recovered without complication. In conclusion, A. viridans should be suspected as an opportunistic pathogen in immunocompromised patients and these patients should be treated according to the antibiotic susceptibility test results.