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Pharmaceuticals (Basel, Switzerland) Apr 2024The formation of microbial biofilm is a self-organizing process among bacterial cells, regulated by quorum-sensing (QS) mechanisms, contributing to development of...
The formation of microbial biofilm is a self-organizing process among bacterial cells, regulated by quorum-sensing (QS) mechanisms, contributing to development of infections. These processes, either separately or in combination, significantly contribute to bacterial resistance to antibiotics and disinfectants. A novel approach to addressing the challenge of treating infections due to antibacterial resistance involves the use of plant metabolites. In recent years, there has been increasing recognition of different phytochemicals as potential modulators. In our study, we evaluated the synergistic effect of chloroform and methanol extracts from species against key virulence factors, including biofilm formation, violacein production, and swarming motility. Each of the 11 examined plant extracts demonstrated the ability to reduce biofilms and pigment synthesis in . Two of the extracts from exhibited significant anti-biofilm and anti-quorum-sensing effects with over 80% inhibition. Their inhibitory effect on violacein synthesis indicates their potential as anti-QS agents, likely attributed to their high concentration of terpenoids (triterpenoids, sesquiterpene lactones, and diterpenoids). Scanning electron microscopy revealed a notable reduction in biofilm biomass, along with changes in biofilm architecture and cell morphology. Additionally, fluorescence microscopy revealed the presence of metabolically inactive cells, indicating the potent activity of the extracts during treatment. These new findings underscore the effectiveness of the plant extracts from the genus as potential anti-virulent agents against . They also propose a promising strategy for preventing or treating its biofilm formation.
PubMed: 38794143
DOI: 10.3390/ph17050573 -
Microorganisms Apr 2024Amid growing concerns about antibiotic resistance, innovative strategies are imperative in addressing bacterial infections in aquaculture. Quorum quenching (QQ), the...
Amid growing concerns about antibiotic resistance, innovative strategies are imperative in addressing bacterial infections in aquaculture. Quorum quenching (QQ), the enzymatic inhibition of quorum sensing (QS), has emerged as a promising solution. This study delves into the QQ capabilities of the probiotic strain D-18 and its products, particularly in 507 communication and biofilm formation. MK was used as a biomarker in this study, and the results confirmed that D-18 effectively inhibits QS. Further exploration into the QQ mechanism revealed the presence of lactonase activity by D-18 that degraded both long- and short-chain acyl homoserine lactones (AHLs). PCR analysis demonstrated the presence of a homologous lactonase-producing gene, ytnP, in the genome of D-18. The study evaluated the impact of D-18 on 507 growth and biofilm formation. The probiotic not only controls the biofilm formation of but also significantly restrains pathogen growth. Therefore, D-18 demonstrates substantial potential for preventing diseases in aquaculture through its QQ capacity. The ability to disrupt bacterial communication and control biofilm formation positions D-18 as a promising eco-friendly alternative to conventional antibiotics in managing bacterial diseases in aquaculture.
PubMed: 38792721
DOI: 10.3390/microorganisms12050890 -
Animals : An Open Access Journal From... May 2024The vaginal tract comprises commensal microorganisms, which play an essential role in the health of the reproductive tract. Any dysbiosis in the vaginal microenvironment...
The vaginal tract comprises commensal microorganisms, which play an essential role in the health of the reproductive tract. Any dysbiosis in the vaginal microenvironment may lead to severe urinary tract infections or even infertility. This study aimed to evaluate the aerobic bacterial flora isolated from vaginal samples from 100 lactating bitches in the antepartum period ( = 3), postpartum period ( = 80), and with ( = 17). Before vaginal swabs, all the bitches went through a gynecology consult, along with milk and blood sampling. Standard microbiological techniques were used for bacterial isolation. Among the 100 vaginal samples analyzed, 82% had a positive microbiological outcome, while 18% were negative. The microbiologic profile listed 17 different genera. The main isolated bacterial families were Micrococcaceae, Staphylococcaceae, Morganellaceae, Bacillaceae, and Rhizobiaceae. At the same time, strains like , , , , , or were isolated for the first time from the vaginal secretion of lactating bitches. The microbiological data demonstrates that lactating bitches' vaginal discharge is heterogeneous and may be affected by coitus, sampling season, age, and reproductive status.
PubMed: 38791718
DOI: 10.3390/ani14101501 -
BMC Infectious Diseases May 2024Chromobacterium violaceum is a rare but severe and often fatal cause of disease in humans. We present 2 clinical cases of sepsis and skin abscesses / cellulitis caused...
Chromobacterium violaceum is a rare but severe and often fatal cause of disease in humans. We present 2 clinical cases of sepsis and skin abscesses / cellulitis caused by C. violaceum seen in a referral hospital for infectious diseases in Vietnam. Both patients survived, but appropriate antibiotic treatment was only installed after culture of the organism. We reviewed and summarised the characteristics of C. violaceum infection and treatment.
Topics: Female; Humans; Anti-Bacterial Agents; Cellulitis; Chromobacterium; Gram-Negative Bacterial Infections; Sepsis; Vietnam; Child; Adolescent
PubMed: 38773469
DOI: 10.1186/s12879-024-09390-1 -
Catalysis Science & Technology May 2024Transaminase enzymes are well established biocatalysts that are used in chemical synthesis due to their beneficial sustainability profile, regio- and stereoselectivity...
Transaminase enzymes are well established biocatalysts that are used in chemical synthesis due to their beneficial sustainability profile, regio- and stereoselectivity and substrate specificity. Here, the use of a wild-type transaminase (TAm) in enzyme cascades revealed the formation of a novel hydroxystyryl pyridine product. Subsequent studies established it was a transaminase mediated reaction where it was exhibiting apparent aldolase reactivity. This promiscuous enzyme reaction mechanism was then explored using other wild-type transaminases and the formation of TAm mutants. Application of one pot multi-step enzyme cascades was subsequently developed to produce a range of hydroxystyryl pyridines.
PubMed: 38721397
DOI: 10.1039/d3cy01370g -
Microbiology Resource Announcements Apr 2024exhibits toxicity to , providing a new infection model to study host homeostasis. Previous studies using pathogen models have proven to be a useful tool to understand...
exhibits toxicity to , providing a new infection model to study host homeostasis. Previous studies using pathogen models have proven to be a useful tool to understand host physiology. Here, we report on the whole-genome sequences of these microbes obtained from short and long reads.
PubMed: 38682773
DOI: 10.1128/mra.00127-24 -
Marine Drugs Apr 2024An ethyl acetate extract of a marine actinomycete strain, SCSIO 53858, isolated from a deep-sea sediment sample in the South China Sea, exhibited anti-quorum-sensing...
An ethyl acetate extract of a marine actinomycete strain, SCSIO 53858, isolated from a deep-sea sediment sample in the South China Sea, exhibited anti-quorum-sensing (QS) activity against CV026. Guided by the anti-QS activity, a novel active compound was isolated and purified from the extract and was identified as 2,3-dimethoxycinnamic acid (2,3-DCA) through spectral data analysis. At a concentration of 150 μg/mL, 2,3-DCA exhibited robust inhibitory effects on three QS-regulated traits of . CV026: violacein production, swarming motility, and biofilm formation, with inhibition rates of 73.9%, 65.9%, and 37.8%, respectively. The quantitative reverse transcription polymerase chain reaction results indicated that 2,3-DCA can disrupt the QS system in . CV026 by effectively suppressing the expression of QS-related genes, including , , , and . Molecular docking analysis revealed that 2,3-DCA hinders the QS system by competitively binding to the same binding pocket on the CviR receptor as the natural signal molecule N-hexanoyl-L-homoserine lactone. Collectively, these findings suggest that 2,3-DCA exhibits promising potential as an inhibitor of QS systems, providing a potential solution to the emerging problem of bacterial resistance.
Topics: Quorum Sensing; Chromobacterium; Molecular Docking Simulation; Anti-Bacterial Agents; Actinobacteria; Cinnamates; Biofilms; Geologic Sediments; Aquatic Organisms; China; Indoles
PubMed: 38667794
DOI: 10.3390/md22040177 -
Annals of Clinical Microbiology and... Apr 2024Chromobacterium is a genus of fourteen species with validly published names, most often found in soil and waters in tropical and subtropical regions around the world....
BACKGROUND
Chromobacterium is a genus of fourteen species with validly published names, most often found in soil and waters in tropical and subtropical regions around the world. The most well-known species of the genus, C. violaceum, occasionally causes clinically relevant infections; cases of soft tissue infections with septicemia and fatal outcomes have been described.
CASE PRESENTATION
Here, we present a clinical case report of a 79-year-old man from Sweden with a soft-tissue infection and septicemia. The pathogen was identified as a strain of Chromobacterium species, but not C. violaceum. The patient was treated with clindamycin and ciprofloxacin and recovered well.
CONCLUSIONS
This case report demonstrates the potential of Chromobacterium species as infectious agents in immunocompetent patients. It also indicates the existence of a novel species.
Topics: Male; Humans; Aged; Chromobacterium; Sweden; Sepsis; Ciprofloxacin; Clindamycin; Gram-Negative Bacterial Infections
PubMed: 38637789
DOI: 10.1186/s12941-024-00692-5 -
Avicenna Journal of Medical... 2024The aim of this study was to determination of Anti-Quorum Sensing (AQS) and anti-biofilm potential of the methanol extract of ginger () rhizomes against...
BACKGROUND
The aim of this study was to determination of Anti-Quorum Sensing (AQS) and anti-biofilm potential of the methanol extract of ginger () rhizomes against multidrug-resistant clinical isolates of ().
METHODS
The AQS activity of ginger was determined against () ATCC 12472 (CV12472), a biosensor strain, in qualitative manner using the agar well diffusion method. The violacein pigment inhibition was assessed to confirm AQS activity of ginger. The AQS potential of sub-minimum Inhibitory Concentrations (sub-MICs) of the ginger extract was determined by targeting different QS regulated virulence factors, including swarming motility (using swarm diameter measurement method), pyocyanin pigment (using chloroform extraction method), Exopolysaccharide (EPS) (using phenol-sulphuric acid method), and biofilm formation (using microtiter plate assay), against clinical isolates (CIs 2, 3, and 4) and standard reference strain of (PA01).
RESULTS
The AQS activity of methanol extract of ginger was confirmed against (CV12472) as inhibition of violacein pigment formation without effecting the growth of CIs and PA01 of . The ginger extract exhibited concentration-dependent inhibition of virulence factors and biofilm formation. The maximum reduction was found in swarming motility, pyocyanin, EPS and biofilm formation against PA01 (51.38%), CI3 (57.91%), PA01 (63.29%) and CI2 (64.37%), respectively at 1/2 MIC of ginger extract.
CONCLUSION
The results of present study revealed the effective AQS and anti-biofilm potential of rhizome methanol extract at a reduced dose (sub-MICs). The extract may be explored as an agent of antimicrobial compounds having AQS and anti-biofilm activity for controlling microbial infection and also for reducing the chances of emergence of resistance in
PubMed: 38605736
DOI: 10.18502/ajmb.v16i1.14171 -
Frontiers in Medicine 2024() is a gram-negative bacillus that is widespread in tropical and subtropical areas. Although rarely infects humans, it can cause critical illness with a mortality...
() is a gram-negative bacillus that is widespread in tropical and subtropical areas. Although rarely infects humans, it can cause critical illness with a mortality rate above 50%. Here, we report the successful treatment of a 15-year-old male who presented with bloodstream infection of along with sepsis, specific skin lesions, and liver abscesses. Cardiogenic shock induced by sepsis was reversed by venoarterial extracorporeal membrane oxygenation (VA ECMO). Moreover, -related purpura fulminans, which is reported herein for the first time, was ameliorated after treatment. This case report demonstrates the virulence of with the aim of raising clinical awareness of this disease.
PubMed: 38596787
DOI: 10.3389/fmed.2024.1342706