Analysis of twelve genomes of the bacterium Kerstersia gyiorum from brown-throated sloths (Bradypus variegatus), the first from a non-human host.

Kerstersia gyiorum is a Gram-negative bacterium found in various animals, including humans, where it has been associated with various infections. Knowledge of the basic biology of K. gyiorum is essential to understand the evolutionary strategies of niche adaptation and how this organism contributes to infectious diseases; however, genomic data about K. gyiorum is very limited, especially from non-human hosts. In this work, we sequenced 12 K. gyiorum genomes isolated from healthy free-living brown-throated sloths (Bradypus variegatus) in the Parque Estadual das Fontes do Ipiranga (São Paulo, Brazil), and compared them with genomes from isolates of human origin, in order to gain insights into genomic diversity, phylogeny, and host specialization of this species. Phylogenetic analysis revealed that these K. gyiorum strains are structured according to host. Despite the fact that sloth isolates were sampled from a single geographic location, the intra-sloth K. gyiorum diversity was divided into three clusters, with differences of more than 1,000 single nucleotide polymorphisms between them, suggesting the circulation of various K. gyiorum lineages in sloths. Genes involved in mobilome and defense mechanisms against mobile genetic elements were the main source of gene content variation between isolates from different hosts. Sloth-specific K. gyiorum genome features include an IncN2 plasmid, a phage sequence, and a CRISPR-Cas system. The broad diversity of defense elements in K. gyiorum (14 systems) may prevent further mobile element flow and explain the low amount of mobile genetic elements in K. gyiorum genomes. Gene content variation may be important for the adaptation of K. gyiorum to different host niches. This study furthers our understanding of diversity, host adaptation, and evolution of K. gyiorum, by presenting and analyzing the first genomes of non-human isolates.

Kerstersia gyiorum isolated for the first time from two patients with neurodegenerative disease: report of two unusual cases and a review of the literature.

With the development of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16S ribosomal RNA (rRNA) gene sequencing, increasing numbers of new microorganisms are being discovered. In this report, Kerstersia gyiorum was isolated for the first time from the sputum of two elderly patients with neurodegenerative disease, and integrated traditional Chinese and Western medicine was used for treatment. The bacteria's growth characteristics, biochemical reaction characteristics, sensitivity to antibiotics, and the patients' treatment are described, with a review of previous reports.

Biological characterization of Kerstersia gyiorum and the construction of the self-built database for mass spectrometry / 中华检验医学杂志

Objective:To investigate the biological characteristics of Kerstersia gyiorum and to support the rapid and accurate identification of Kerstersia gyiorum on mass spectrometry by using Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) for self-built libraries. Methods:From November 2020 to February 2022, thirty-eight strains of Kerstersia gyiorum isolated from clinical patients of the General Hospital of Southern Theatre Command were collected and identified by the fully automated microbial analysis system (Vitek-2 Compact), the automatic microbial mass spectrometry detection system (Vitek-MS) and the 16S ribosomal RNA sequencing. Thirteen strains were randomly selected and mass spectra were obtained by using Vitek-MS. The SARAMIS software was used to construct a Kerstersia gyiorum library, and the remaining 25 strains were used to validate the constructed library. Results:The Vitek-2 Compact and Vitek MS were unable to identify Kerstersia gyiorum; 13 strains were successfully built into a self-built library of Kerstersia gyiorum by SARAMIS software, and 25 validated strains were identified as Kerstersia gyiorum with a confidence level of more than 99.0% and 100% (25/25) accuracy. Conclusion:Kerstersia gyiorum has unique mass spectrometry profile, which can be identified as species quickly and accurately by the establishment of the self-constructed library of profiles.

A case of Bordetella trematum and Kerstersia gyiorum infections in a patient with congestive dermatitis.

Bordetella trematum and Kerstersia gyiorum are rare gram-negative bacilli that are not frequently detected in human infections. In this report, we describe a case of a 48-year-old man who presented to our hospital with an infected wound on his leg. Discharges from the cracks of the granulation were collected and evaluated in our microbiology laboratory. Gram staining of the specimen showed polymorphonuclear leukocytes and abundant gram-negative bacilli. Three types of colonies were isolated on blood agar and were identified as B. trematum and Alcaligenes faecalis using VITEK MS. Moreover, K. gyiorum and B. trematum were identified and confirmed via 16S ribosomal RNA (rRNA) gene sequencing. The patient successfully recovered following application of meropenem antibacterial therapy and surgical debridement. This is the first reported case of complex wound infection caused by both B. trematum and K. gyiorum. Identification of B. trematum has recently been made possible by routine bacterial identification using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). However, K. gyiorum isolation is still rare, and species identification requires 16S rRNA sequencing. Thus, this case highlighted the importance of using multiple methods, such as MALDI-TOF MS and 16S rRNA gene sequencing, for identification of rarely isolated species from clinical specimens.

Chronic lower extremity wound infection due to Kerstersia gyiorum in a patient with Buerger's disease: a case report.

BACKGROUND: Kerstersia gyiorum is an extremely rare pathogen of human infection. It can cause chronic infection in patients with underlying conditions. It can easily be misdiagnosed if proper diagnostic methods are not used. CASE PRESENTATION: A 47-year-old male patient with a history of Buerger's Disease for 28 years presented to our hospital with an infected chronic wound on foot. The wound was debrided, and the specimen was sent to Microbiology laboratory. Gram staining of the specimen showed abundant polymorphonuclear leukocytes and gram-negative bacilli. Four types of colonies were isolated on blood agar. These were identified as Kerstersia gyiorum, Proteus vulgaris, Enterobacter cloacae, Morganella morganii by Maldi Biotyper (Bruker Daltonics, Germany). The identification of K. gyiorum was confirmed by 16S ribosomal RNA gene sequencing. The patient was successfully recovered with antimicrobial therapy, surgical debridement, and skin grafting. CONCLUSIONS: This is the first case of wound infection due to K. gyiorum in a patient with Buerger's Disease. We made a brief review of K. gyiorum cases up to date. Also, this case is presented to draw attention to the use of new and advanced methods like MALDI-TOF MS and 16S rRNA gene sequencing for identification of rarely isolated species from clinical specimens of patients with chronic infections and with chronic underlying conditions.

Isolation of culturable aerobic bacteria and evidence of Kerstersia gyiorum from the blowhole of captive Yangtze finless porpoises.

Bacterial respiratory illnesses are problematic in aquatic mammals such as the Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis; YFP), which is now at a critically endangered status. Yet little is known about the bacteria inhabiting the respiratory tract of YFPs. In this study, we preliminarily characterized the culturable aerobic bacteria from blow samples of captive YFPs. The bacterial diversity was assessed through cultivation by direct exhalation onto Columbia blood agar plates and identification of representative isolates through 16S rRNA gene sequence analysis. In total, eleven bacterial species belonging to four phyla Proteobacteria (71 %), Firmicutes (25 %), Bacteroidetes (3 %) and Actinobacteria (1 %) were identified. Most of these isolates were opportunistic pathogens found in respiratory illnesses in humans and animals. We also reported the first case of Kerstersia gyiorum isolated from an animal. This work provides a preliminary assessment of the bacteria present in the respiratory tract of captive YFPs, which will be an important first step in elucidating the roles of normal microbiota in maintaining respiratory health of YFPs. This study also points out the necessity of future long-term monitoring of blowhole microorganisms in the YFPs and making emergency preparedness plans for respiratory tract infections. These measures can aid in assessing the pathogenic risk of the critically endangered YFP populations.

A first case of isolation of Kerstersia gyiorum from urinary tract.

An 82-year-old man with percutaneous nephrostomy presented to our Hospital with dysuria for one day. The patient's percutaneous nephrostomy tube was exchanged, with about 20 mL of creamy purulent urine being collected. Direct smear of the urine specimen showed polymorphonuclear leukocytes and small Gram-negative bacilli, some of which had undergone phagocytosis. This organism was identified as Kerstersia gyiorum using 16S ribosomal RNA gene analysis. He was successfully recovered with exchange of his percutaneous nephrostomy tube and fluoroquinolone internal use treatment. This is the first case report of urinary tract infection due to K. gyiorum.

A case of chronic suppurative otitis media caused by Kerstersia gyiorum.

Chronic suppurative otitis media is inflammation of the middle ear and mastoid that involves discharge and hearing loss. Kerstersia gyiorum is a member of the Alcaligenaceae family that who could not be treated with classical treatments such as patients with chronic otitis media, neck abscesses. K. gyiorum strain isolated from a patient with chronic suppurative otitis media.

Two cases of chronic suppurative otitis media caused by Kerstersia gyiorum in Tanzania: is it an underappreciated pathogen in chronic otitis media?

Two cases of mixed infection involving Kerstersia gyiorum causing chronic suppurative otitis media (CSOM) have been reported worldwide. We report, for the first time, two cases of CSOM due to mixed infections involving K. gyiorum in adults in Africa. Both isolates were intermediate susceptible to ciprofloxacin based on European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints.