Extended characterization of Corynebacterium pyruviciproducens based on clinical strains from Canada and Switzerland

Acute Bacterial Prostatitis in a 12-Year-Old Boy Without Any Underlying Disease

Acute bacterial prostatitis (ABP) is a common disease in adults but uncommon in children. Here, we report the case of a pediatric patient without any underlying disease who was diagnosed with ABP while trying to determine the cause of fever refractory to antimicrobial therapy. A previously healthy 12-year-old boy presented with a 13-day history of fever and malaise despite initial antimicrobial treatment. Further tests revealed pyuria and enlarged prostate with possible abscesses, which led to the diagnosis of ABP based on a contrast-enhanced computed tomography (CT) scan. Although initial urine cultures were negative, Corynebacterium pyruviciproducens was detected in subsequent cultures. Antimicrobial therapy for 10 weeks led to improvement without relapse. This case demonstrates that ABP can cause fever in children. Moreover, it shows that contrast-enhanced CT imaging can help identify the cause of fever and that administration of antimicrobials before adequate investigations can confound the diagnosis and complicate the treatment.

Genomic and phenotypic analysis of a novel clinical isolate of Corynebacterium pyruviciproducens

BACKGROUND

Corynebacterium pyruviciproducens is a recently described species of Corynebacterium. There are few reports on the microbiological characteristics of the new species, and there is a lack of reports on the genomic analysis of the species.

RESULTS

This study involved a clinical isolate from the pus of a hospital patient with sebaceous gland abscesses. The clinically isolated strain was identified as C. pyruviciproducens strain WYJY-01. In this study, referring to Koch's postulates, we observed the pathological changes of animal models infected by intraperitoneal injection and subcutaneous injection of pure culture of the strain WYJY-01. Furthermore, the strain WYJY-01 was isolated and cultured again from animal models' subcutaneous abscess drainage fluid. Subsequently, the genomics of the strain WYJY-01 was analyzed. By comparing various gene databases, this study predicted the core secondary metabolite gene cluster of the strain WYJY-01, virulence factor genes carried by prophage, pathogenicity islands, and resistance islands. In addition, the genomes of C. pyruviciproducens strain WYJY-01, ATCC BAA-1742 T, and UMB0763 were analyzed by comparative genomics, and the differential genes of strain WYJY-01 were compared, and their functions were analyzed.

CONCLUSION

The findings showed that the strain WYJY-01 had pathogenicity, supplementing the phenotype characteristics of C. pyruviciproducens. Meanwhile, this research revealed the possible molecular mechanism of the pathogenicity of the strain WYJY-01 at the gene level through whole genome sequence analysis, providing a molecular basis for further research.

The changes of microbial diversity and flavor compounds during the fermentation of millet Huangjiu, a traditional Chinese beverage

Huangjiu is a national alcoholic beverage in China. Millet has congenital advantages in development and utilization of nutrient. Brewing Huangjiu with millet can increase the value of millet. Microbial community plays crucial roles in millet Huangjiu fermentation. Flavor compounds reflect the quality and health function of Huangjiu. The flavor compounds of Huangjiu are complex and their formation is closely associated with microorganisms, but the relationship between them during fermentation has been unknown. In this research, this relationship during millet Huangjiu fermentation were deeply investigated. Totally 86 volatile compounds were detected. Bacillus, Weissella, Paenibacillus, Klebsiella, Prevotella was investigated as the dominant microbes through high-throughput sequencing. 537 correlations between major flavor compounds and microbes were established to reflect the dynamic change during millet Huangjiu fermentation. The top five dominant genus of flavor producing microbes were Chryseobacterium, Sporolactobacillus, Psychrobacter, Sphingobium and Anoxybacillus. The content of malic acid and citric acid was gradually improved all through the millet Huangjiu fermentation. Malic acid and citric acid generated from millet Huangjiu fermentation shows healthy properties as liver protection and eliminating fatigue. Our research provides essential information on microbial community succession and the flavor formation during millet Huangjiu fermentation, and beneficial for development of Huangjiu products.

Outbreak investigation for toxigenic Corynebacterium diphtheriae wound infections in refugees from Northeast Africa and Syria in Switzerland and Germany by whole genome sequencing

Toxigenic Corynebacterium diphtheriae is an important and potentially fatal threat to patients and public health. During the current dramatic influx of refugees into Europe, our objective was to use whole genome sequencing for the characterization of a suspected outbreak of C. diphtheriae wound infections among refugees. After conventional culture, we identified C. diphtheriae using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and investigated toxigenicity by PCR. Whole genome sequencing was performed on a MiSeq Illumina with >70×coverage, 2×250 bp read length, and mapping against a reference genome. Twenty cases of cutaneous C. diphtheriae in refugees from East African countries and Syria identified between April and August 2015 were included. Patients presented with wound infections shortly after arrival in Switzerland and Germany. Toxin production was detected in 9/20 (45%) isolates. Whole genome sequencing-based typing revealed relatedness between isolates using neighbour-joining algorithms. We detected three separate clusters among epidemiologically related refugees. Although the isolates within a cluster showed strong relatedness, isolates differed by >50 nucleotide polymorphisms. Toxigenic C. diphtheriae associated wound infections are currently observed more frequently in Europe, due to refugees travelling under poor hygienic conditions. Close genetic relatedness of C. diphtheriae isolates from 20 refugees with wound infections indicates likely transmission between patients. However, the diversity within each cluster and phylogenetic time-tree analysis suggest that transmissions happened several months ago, most likely outside Europe. Whole genome sequencing offers the potential to describe outbreaks at very high resolution and is a helpful tool in infection tracking and identification of transmission routes.