-
Communications Chemistry May 2023Proteorhodopsins (PRs), bacterial light-driven outward proton pumps comprise the first discovered and largest family of rhodopsins, they play a significant role in life...
Proteorhodopsins (PRs), bacterial light-driven outward proton pumps comprise the first discovered and largest family of rhodopsins, they play a significant role in life on the Earth. A big remaining mystery was that up-to-date there was no described bacterial rhodopsins pumping protons at acidic pH despite the fact that bacteria live in different pH environment. Here we describe conceptually new bacterial rhodopsins which are operating as outward proton pumps at acidic pH. A comprehensive function-structure study of a representative of a new clade of proton pumping rhodopsins which we name "mirror proteorhodopsins", from Sphingomonas paucimobilis (SpaR) shows cavity/gate architecture of the proton translocation pathway rather resembling channelrhodopsins than the known rhodopsin proton pumps. Another unique property of mirror proteorhodopsins is that proton pumping is inhibited by a millimolar concentration of zinc. We also show that mirror proteorhodopsins are extensively represented in opportunistic multidrug resistant human pathogens, plant growth-promoting and zinc solubilizing bacteria. They may be of optogenetic interest.
PubMed: 37130895
DOI: 10.1038/s42004-023-00884-8 -
Annals of African Medicine 2022Sphingomonas paucimobilis is a Gram-negative bacteria identified as a rare infectious agent, more commonly seen among immune-compromised hosts. Infections include...
Sphingomonas paucimobilis is a Gram-negative bacteria identified as a rare infectious agent, more commonly seen among immune-compromised hosts. Infections include bacteremia, septicemia leading to septic shock, bone and soft-tissue infections such as septic arthritis, osteomyelitis, infection of shunts, and implantable devices. Although the organism has been reported to have low pathogenicity, infections in the immune compromised can be devastating leading to even death.
Topics: Anti-Bacterial Agents; Bacteremia; Gram-Negative Bacterial Infections; Humans; Sepsis; Sphingomonas; Steroids
PubMed: 36204921
DOI: 10.4103/aam.aam_120_21 -
Japanese Journal of Infectious Diseases Jul 2022Sphingomonas paucimobilis is an aerobic, non-fermentative, opportunistic Gram-negative bacillus found in water systems. This study was conducted to analyze concurrent S.... (Review)
Review
Sphingomonas paucimobilis Outbreak a Pediatric Hematology-Oncology Hospital: Epidemiological Investigation and Literature Review of an Emerging Healthcare-Associated Infection.
Sphingomonas paucimobilis is an aerobic, non-fermentative, opportunistic Gram-negative bacillus found in water systems. This study was conducted to analyze concurrent S. paucimobilis bacteremia cases and treatment outcomes, potential outbreak sources, and antimicrobial resistance profiles. This ambidirectional cohort study was conducted in a 30-bed pediatric hematology-oncology hospital. The patients' ages ranged from 1 to 17 years, with a median age of 5 years. Environmental sampling was applied to investigate the outbreak source. Bacterial identification and antimicrobial susceptibility tests of the isolated bacteria were performed using the disk diffusion method and Vitek®2 automated system. S. paucimobilis was detected in 181 blood culture samples from 51 patients over 2 years and was isolated from hot tap water. Acute lymphoblastic leukemia (ALL) was diagnosed for 66% of patients, and two of our patients with ALL died due to S. paucimobilis sepsis. S. paucimobilis isolates are susceptible to carbapenems and quinolones. Surveillance and epidemic control should be performed for hospital-acquired infectious agents such as S. paucimobilis. In additon, water distribution systems should be checked for colonizing agents at regular intervals.
Topics: Adolescent; Anti-Bacterial Agents; Anti-Infective Agents; Child; Child, Preschool; Cohort Studies; Cross Infection; Delivery of Health Care; Disease Outbreaks; Gram-Negative Bacterial Infections; Hematology; Hospitals; Humans; Infant; Sphingomonas; Water
PubMed: 35095025
DOI: 10.7883/yoken.JJID.2021.661 -
International Journal of Infectious... Jun 2022Small case series and reports suggest that Sphingomonas paucimobilis is predominantly a cause of nosocomial bloodstream infections (BSI) with very low associated...
BACKGROUND
Small case series and reports suggest that Sphingomonas paucimobilis is predominantly a cause of nosocomial bloodstream infections (BSI) with very low associated mortality. Our objective was to describe the epidemiology and outcome of Sphingomonas species BSI in a large Australian population.
METHODS
We included all residents of Queensland, Australia, with BSI because of Sphingomonas species identified within the publicly funded system from 2000 to 2019.
RESULTS
A total of 282 incident episodes of Sphingomonas species BSI were identified for an age- and sex-adjusted incidence of 3.2 per million population annually. Incidence rates were highest in the tropical regions of the state. Most (94%) of the isolates were confirmed as Sphingomonas paucimobilis. In addition, 77% of the infections were community-onset, of which 48% were community-associated, and 30% were healthcare-associated. The very young, the old, and male patients were at the highest risk. Patients with community-associated disease were, on average, younger, had fewer co-morbidities, and were less likely to have polymicrobial infections. At least 1 co-morbidity was identified in 62% of patients, with malignancy, diabetes, and lung disease most prevalent. The overall all-cause 30-day case-fatality rate was 6%.
CONCLUSION
Sphingomonas paucimobilis BSI is a predominantly community-onset disease associated with a significant risk of death.
Topics: Australia; Bacteremia; Cross Infection; Humans; Male; Sepsis; Sphingomonas
PubMed: 35398302
DOI: 10.1016/j.ijid.2022.03.060 -
International Journal of Environmental... Feb 2022The opportunistic infections with Gram-negative bacilli are frequently reported. The clinical studies are focused on the course of human infectious and very often the... (Review)
Review
The opportunistic infections with Gram-negative bacilli are frequently reported. The clinical studies are focused on the course of human infectious and very often the source of infection remain unclear. We aim to see if the Gram-negative bacilli isolated from a non-contaminated environment-the caves-are reported in human infections. Eleven samples were collected from six Romanian caves. We used the standard procedure used in our clinical laboratory for bacterial identification and for antibiotic susceptibility testing of the cave isolates. Out of the 14 bacterial strains, three isolates are Gram-negative bacilli-one isolate belong to and two strains belong to . We screened for the published studies-full-text original articles or review articles-that reported human infections with and Data sources-PubMed and Cochrane library. We retrieved 447 cases from 49 references-262 cases (58.61%) are infections and 185 cases (41.39%) are infections. The types of infections are diverse but there are some infections more frequent; there are 116 cases (44.27%) and many infections of the bloodstream with (116 cases) and 121 cases (65.41%) are urinary tract infections with . The acquired source of the bloodstream infections is reported for 93 of bloodstream infections-50 cases (43%) are hospital-acquired, and 40 cases (37%) are community-acquired. Most of the infections are reported in patients with different underlying conditions. There are 80 cases (17.9%) are reported of previously healthy persons. Out of the 72 cases of pediatric infections, 62 cases (86.11%) are caused by . There are ten death casualties-three are infections, and seven are infections.
Topics: Caves; Child; Gram-Negative Bacterial Infections; Hafnia alvei; Humans; Sphingomonas
PubMed: 35206510
DOI: 10.3390/ijerph19042324 -
Brazilian Journal of Microbiology :... Sep 2023Silver (Ag) is currently obtained from primary and secondary sources through hydrometallurgical and pyrometallurgical processes. However, these processes consume high...
Silver (Ag) is currently obtained from primary and secondary sources through hydrometallurgical and pyrometallurgical processes. However, these processes consume high amounts of energy and are environmentally unfriendly. The search for bacteria tolerant with a high leaching capacity for to Ag is therefore a necessary requirement as part of the development of bioleaching technologies with reduced impact on the environment and lower energy expenditure. In this sense, the objective of this research was to evaluate the tolerance of Sphingomonas paucimobilis MX8 to Ag added to nutrient agar, and to determine whether this tolerance could favor the bioleaching of Ag present on the printed circuit boards (PCBs) of computer keyboards. The bacteria Sphingomonas paucimobilis MX8 was cultured in Petri dishes with nutrient agar and four different concentrations of AgNO (200, 400, 600, and 800 mg L) at 28 °C for 10 days. For the bioleaching experiment, the bacteria were grown in a mineral medium with computer keyboard PCBs for 30 days at room temperature (17 to 22 °C) and centrifugation at 150 rpm. The results indicate that Sphingomonas paucimobilis MX8 is tolerant to Ag and forms a silvery halo around its growth in the presence of this metal. Furthermore, Sphingomonas paucimobilis MX8 was able to bioleach 12% of the Ag found in computer keyboard PCBs. The results obtained could help generate more environmentally friendly silver bioleaching processes in which the silver bioleaching capacity of this bacterium is increased.
Topics: Silver; Agar; Recycling; Electronic Waste; Culture Media; Bacteria; Computers
PubMed: 37171535
DOI: 10.1007/s42770-023-00994-4 -
Cureus Jul 2022usually exhibits low virulence likely secondary to its lack of lipopolysaccharide A. Infections caused by more commonly afflict immunocompromised patients. Some case...
usually exhibits low virulence likely secondary to its lack of lipopolysaccharide A. Infections caused by more commonly afflict immunocompromised patients. Some case reports document pneumonia, osteomyelitis, pyomyoma, and septic arthritis secondary to in immunocompetent patients. bacteremia is associated with underlying conditions, including malignancy, diabetes mellitus, end-stage renal disease, and chronic obstructive pulmonary disease. Bacteremia has the potential to lead to septic shock. Antimicrobial effectiveness varies, and the mechanism that leads to resistance has not yet been elucidated. This underscores the importance of antimicrobial susceptibility testing. We present a unique case of community-acquired bacteremia and resultant septic shock in an immunocompetent patient. A 90-year-old female with a history of chronic kidney disease, acute colonic infarction status post colostomy, gastroesophageal reflux disease, hypertension, supraventricular tachycardia, and schizoaffective disorder presented to the emergency department with hypotension and altered mental status. Urinalysis and chest X-ray were unremarkable. Antibiotic therapy with cefepime was initiated following gram stain, which showed gram-negative rods. The blood culture revealed . The patient was discharged with the plan to enter hospice care.
PubMed: 35959187
DOI: 10.7759/cureus.26720 -
Iranian Journal of Microbiology Oct 2021is an opportunistic pathogen and was rarely encountered in clinical specimens previously. This study aimed to investigate the clinical features, associated...
BACKGROUND AND OBJECTIVES
is an opportunistic pathogen and was rarely encountered in clinical specimens previously. This study aimed to investigate the clinical features, associated co-morbidities, and antimicrobial susceptibility patterns of infection in a tertiary hospital in Uttarakhand.
MATERIALS AND METHODS
isolates cultured from various sections of hospital and OPDs were identified and analyzed for their antibiograms in the microbiology laboratory for a duration of one year from January 2020 to December 2020.
RESULTS
was isolated from 49 samples (0.01%) out of 3792 samples processed in VITEK 2 Compact automated ID/AST instrument. The maximum number of isolates were obtained from urine samples (31%), followed by blood (24%). Septicemia (41%), meningitis (17%), lower respiratory tract infections and ventilator associated pneumonia (14%) constituted a major portion of infections caused by this organism. Diabetes mellitus (22%) and steroid usage (16%) were major associated co-morbid conditions. Third and Fourth generation cephalosporins like ceftriaxone (81%) and cefepime (86%) were found to be the most susceptible drugs whereas 61% of isolates were resistant to colistin.
CONCLUSION
This organism is an up-and-coming pathogen and should not be simply labeled as a contaminant. Although the organism is not grossly virulent and still might not be associated with serious life-threatening infections; however their evolving resistance patterns and increased spectrum of infections should be seriously taken into account.
PubMed: 34900159
DOI: 10.18502/ijm.v13i5.7425 -
Microorganisms Apr 2021An aerobic, yellow-pigmented, bacteriochlorophyll -producing strain, designated AAP5 (=DSM 111157=CCUG 74776), was isolated from the alpine lake Gossenköllesee located...
An aerobic, yellow-pigmented, bacteriochlorophyll -producing strain, designated AAP5 (=DSM 111157=CCUG 74776), was isolated from the alpine lake Gossenköllesee located in the Tyrolean Alps, Austria. Here, we report its description and polyphasic characterization. Phylogenetic analysis of the 16S rRNA gene showed that strain AAP5 belongs to the bacterial genus and has the highest pairwise 16S rRNA gene sequence similarity with (98.3%), (96.8%), and (96.5%). Its genomic DNA G + C content is 65.9%. Further, in silico DNA-DNA hybridization and calculation of the average nucleotide identity speaks for the close phylogenetic relationship of AAP5 and . The high percentage (76.2%) of shared orthologous gene clusters between strain AAP5 and NCTC 11030, the type species of the genus, supports the classification of the two strains into the same genus. Strain AAP5 was found to contain C7 (64.6%) as a predominant fatty acid (>10%) and the polar lipid profile contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, six unidentified glycolipids, one unidentified phospholipid, and two unidentified lipids. The main respiratory quinone was ubiquinone-10. Strain AAP5 is a facultative photoheterotroph containing type-2 photosynthetic reaction centers and, in addition, contains a xathorhodopsin gene. No CO-fixation pathways were found.
PubMed: 33917603
DOI: 10.3390/microorganisms9040768 -
Medicina (Kaunas, Lithuania) Mar 2023is a gram-negative bacillus that is widely distributed in the environment but rarely causes infections in humans. Meningitis caused by is an extremely rare clinical... (Review)
Review
is a gram-negative bacillus that is widely distributed in the environment but rarely causes infections in humans. Meningitis caused by is an extremely rare clinical entity with very few reported cases in the literature. The clinical presentation and management of meningitis are not well established, and further research is needed to better understand this rare infection. Therefore, the goal of this study was to present probably the only case of meningitis caused by co-infection with and and to describe the diagnostic and therapeutic challenges encountered, in correlation with the other very few reported cases of meningitis. A 64-year-old male farmer residing in a rural area was admitted with symptoms of severe headache, somnolence, and confusion. He had several comorbidities, including adrenal insufficiency, duodenal ulcer, and hypercholesterolemia. Lumbar puncture showed elevated leukocyte counts, glucose, and a marked rise of cerebrospinal fluid (CSF) proteins, indicating bacterial meningitis, which was confirmed by CSF culture that isolated and . Antituberculosis therapy was initiated with isoniazid (300 mg/day), rifampicin (600 mg/day), pyrazinamide (2000 mg/day), and streptomycin (1 g/day). Ceftriaxone was introduced nine days later, after CSF culture grew , and was discharged without complications after 40 days of hospitalization. The literature search revealed a total of 12 published cases of meningitis in patients ranging from two months old to 66 years old. Among these cases, eight (66%) reported a favorable outcome, while two (17%) cases resulted in a poor outcome, and two (17%) were fatal. It was observed among the 13 identified cases (including ours) that the CSF white blood cell count had an average of 178.9 × 10/mm, an average glucose level of 33.0 mg/dL, and an average protein count of 294.2 mg/dL. Most cases improved appropriately under antibiotic therapy with intravenous ceftriaxone, Meropenem, and Vancomycin. In conclusion, although extremely rare, meningitis has good outcomes even in immunocompromised patients with appropriate antibiotic therapy and close monitoring, while the diagnosis should not be excluded even in immunocompetent patients.
Topics: Male; Humans; Middle Aged; Infant; Mycobacterium tuberculosis; Ceftriaxone; Anti-Bacterial Agents; Meningitis, Bacterial; Immunocompromised Host
PubMed: 37109645
DOI: 10.3390/medicina59040687