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Microbiology Spectrum Jun 2022Prodigiosin possesses antibacterial activities, but as a highly hydrophobic compound, it raised the question about how Serratia marcescens introduce this compound to...
Prodigiosin possesses antibacterial activities, but as a highly hydrophobic compound, it raised the question about how Serratia marcescens introduce this compound to other microbes. Here, we demonstrate that the production of prodigiosin by newly isolated S. marcescens RH10 correlates with its antibacterial activity against a multidrug-resistant strain of S. aureus, with this pathogen's viability decreasing 6-log over 24 h. While S. marcescens RH10 does secrete membrane vesicles that carry prodigiosin, this antibiotic was not active in this form, with 5 mg/L prodigiosin leading to only a 1.22-fold reduction in the S. aureus viability while the same quantity of purified prodigiosin led to a 2800-fold reduction. Contact assays, however, showed increased activity, with a 3-log loss in the S. aureus viabilities in only 6 h as long as production of prodigiosin occurred. The role of prodigiosin was confirmed further by generating an isogenic Δ mutant in S. marcescens RH10, based on the draft genome sequence reported here, to inhibit the synthesis of prodigiosin. In all experiments performed, this mutant was unable to kill S. aureus. Finally, the possibility that the type VI secretion system present in S. marcescens may also be important was also explored as it is known to be used by this strain to kill other microbes. The results here, however, found no obvious activity against S. aureus. In conclusion, the results presented here show prodigiosin requires both cell-to-cell contact and synthesis for it to be effective as an antibiotic for its native host. The antibacterial activities of prodigiosin are well-established but, as a hydrophobic molecule, the mechanisms used to introduce it to susceptible microbes has never been studied. We found here, in contrast to violacein, another hydrophobic antibiotic that can be transferred using membrane vesicles (MVs), prodigiosin is also carried from Serratia marcescens in MVs released but its resulting activities were severely mitigated compared to the freely added compound, suggesting it is more tightly bound to the MVs than violacein. This led us to hypothesize that cell-to-cell contact is needed, which we demonstrate here. As well, we show synthesis of prodigiosin is needed for it to be effective. As violacein- and prodigiosin-producing bacterial strains are both beneficial to amphibians, where they help protect the skin against pathogens, the findings presented here provide an important ecological perspective as they show the mechanisms used differ according to the antibacterial produced.
Topics: Anti-Bacterial Agents; Prodigiosin; Serratia marcescens; Staphylococcus aureus
PubMed: 35435740
DOI: 10.1128/spectrum.00607-22 -
Scientific Reports Jan 2019Serratia marcescens is a Gram-negative bacterial species that can be found in a wide range of environments like soil, water and plant surfaces, while it is also known as... (Comparative Study)
Comparative Study
Serratia marcescens is a Gram-negative bacterial species that can be found in a wide range of environments like soil, water and plant surfaces, while it is also known as an opportunistic human pathogen in hospitals and as a plant growth promoting bacteria (PGPR) in crops. We have used a pangenome-based approach, based on publicly available genomes, to apply whole genome multilocus sequence type schemes to assess whether there is an association between source and genotype, aiming at differentiating between isolates from nosocomial sources and the environment, and between strains reported as PGPR from other environmental strains. Most genomes from a nosocomial setting and environmental origin could be assigned to the proposed nosocomial or environmental MLSTs, which is indicative of an association between source and genotype. The fact that a few genomes from a nosocomial source showed an environmental MLST suggests that a minority of nosocomial strains have recently derived from the environment. PGPR strains were assigned to different environmental types and clades but only one clade comprised strains accumulating a low number of known virulence and antibiotic resistance determinants and was exclusively from environmental sources. This clade is envisaged as a group of promissory MLSTs for selecting prospective PGPR strains.
Topics: Computational Biology; Cross Infection; Environmental Microbiology; Genetic Variation; Genome, Bacterial; Genotype; Humans; Multilocus Sequence Typing; Serratia Infections; Serratia marcescens
PubMed: 30631083
DOI: 10.1038/s41598-018-37118-0 -
British Medical Journal (Clinical... Dec 1983
Topics: Adult; Anti-Bacterial Agents; Drug Resistance, Microbial; Enterobacteriaceae Infections; Humans; Infant, Newborn; Serratia marcescens
PubMed: 6416536
DOI: 10.1136/bmj.287.6406.1651 -
PloS One 2020Association of bacteria with fungi is a major area of research in infection biology, however, very few strains of bacteria have been reported that can invade and reside...
Association of bacteria with fungi is a major area of research in infection biology, however, very few strains of bacteria have been reported that can invade and reside within fungal hyphae. Here, we report the characterization of an endofungal bacterium Serratia marcescens D1 from Mucor irregularis SS7 hyphae. Upon re-inoculation, colonization of the endobacterium S. marcescens D1 in the hyphae of Mucor irregularis SS7 was demonstrated using stereo microscopy. However, S. marcescens D1 failed to invade into the hyphae of the tested Ascomycetes (except Fusarium oxysporum) and Basidiomycetes. Remarkably, Serratia marcescens D1 could invade and spread over the culture of F. oxysporum that resulted in mycelial death. Prodigiosin, the red pigment produced by the Serratia marcescens D1, helps the bacterium to invade fungal hyphae as revealed by the increasing permeability in fungal cell membrane. On the other hand, genes encoding the type VI secretion system (T6SS) assembly protein TssJ and an outer membrane associated murein lipoprotein also showed significant up-regulation during the interaction process, suggesting the involvement of T6SS in the invasion process.
Topics: Cell Membrane; Hyphae; Mucor; Serratia marcescens; Symbiosis; Type VI Secretion Systems
PubMed: 32320394
DOI: 10.1371/journal.pone.0224051 -
Journal of Clinical Pathology Jul 1971During a four-month period an intensive effort was made to isolate and identify every Serratia marcescens strain present in the clinical material received for...
During a four-month period an intensive effort was made to isolate and identify every Serratia marcescens strain present in the clinical material received for bacteriological assessment in the laboratory. Ten strains were isolated from eight patients, the organism possibly being responsible for infection in five of these patients. Serratia marcescens is thus commoner than expected and it is difficult to explain the fact that there are so few references to it as a pathogen in the British literature.
Topics: Aged; Blood; Female; Humans; Male; Middle Aged; Serotyping; Serratia marcescens; Sputum; United Kingdom; Urine
PubMed: 4937136
DOI: 10.1136/jcp.24.5.444 -
Brazilian Journal of Microbiology :... Mar 2021Serratia marcescens are gram-negative bacteria found in several environmental niches, including the plant rhizosphere and patients in hospitals. Here, we present the...
Serratia marcescens are gram-negative bacteria found in several environmental niches, including the plant rhizosphere and patients in hospitals. Here, we present the genome of Serratia marcescens strain N4-5 (=NRRL B-65519), which has a size of 5,074,473 bp (664-fold coverage) and contains 4840 protein coding genes, 21 RNA genes, and an average G + C content of 59.7%. N4-5 harbours a plasmid of 11,089 bp and 43.5% G + C content that encodes six unique CDS repeated 2.5× times totalling 13 CDS. Our genome assembly and manual curation uncovered the insertion of two extra copies of the 5S rRNA gene in the assembled sequence, which was confirmed by PCR and Sanger sequencing to be a misassembly. This artefact was subsequently removed from the final assembly. The occurrence of extra copies of the 5S rRNA gene was also observed in most complete genomes of Serratia spp. deposited in public databases in our comparative analysis. These elements, which also occur naturally, can easily be confused with true genetic variation. Efforts to discover and correct assembly artefacts should be made in order to generate genome sequences that represent the biological truth underlying the studied organism. We present the genome of N4-5 and discuss genes potentially involved in biological control activity against plant pathogens and also the possible mechanisms responsible for the artefact we observed in our initial assembly. This report raises awareness about the extra copies of the 5S rRNA gene in sequenced bacterial genomes as they may represent misassemblies and therefore should be verified experimentally.
Topics: Base Composition; Biological Control Agents; Genome, Bacterial; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Serratia marcescens; Whole Genome Sequencing
PubMed: 32965626
DOI: 10.1007/s42770-020-00382-2 -
Nucleic Acids Research Jan 2022Serratia marcescens is a Gram-negative bacterium of the Enterobacteriaceae family that can produce numbers of biologically active secondary metabolites. However, our...
Serratia marcescens is a Gram-negative bacterium of the Enterobacteriaceae family that can produce numbers of biologically active secondary metabolites. However, our understanding of the regulatory mechanisms behind secondary metabolites biosynthesis in S. marcescens remains limited. In this study, we identified an uncharacterized LysR family transcriptional regulator, encoding gene BVG90_12635, here we named psrA, that positively controlled prodigiosin synthesis in S. marcescens. This phenotype corresponded to PsrA positive control of transcriptional of the prodigiosin-associated pig operon by directly binding to a regulatory binding site (RBS) and an activating binding site (ABS) in the promoter region of the pig operon. We demonstrated that L-proline is an effector for the PsrA, which enhances the binding affinity of PsrA to its target promoters. Using transcriptomics and further experiments, we show that PsrA indirectly regulates pleiotropic phenotypes, including serrawettin W1 biosynthesis, extracellular polysaccharide production, biofilm formation, swarming motility and T6SS-mediated antibacterial activity in S. marcescens. Collectively, this study proposes that PsrA is a novel regulator that contributes to antibiotic synthesis, bacterial virulence, cell motility and extracellular polysaccharides production in S. marcescens and provides important clues for future studies exploring the function of the PsrA and PsrA-like proteins which are widely present in many other bacteria.
Topics: Bacterial Proteins; Biofilms; Depsipeptides; Movement; Operon; Polysaccharides, Bacterial; Prodigiosin; Promoter Regions, Genetic; Serratia marcescens; Transcription Factors
PubMed: 34893884
DOI: 10.1093/nar/gkab1186 -
The Journal of Hygiene Aug 1984An epidemic caused by Serratia marcescens that involved 26 infants admitted to the Neonatal Intensive Care Unit (NICU) and 82 infants admitted to the Nursery of the 2nd...
An epidemic caused by Serratia marcescens that involved 26 infants admitted to the Neonatal Intensive Care Unit (NICU) and 82 infants admitted to the Nursery of the 2nd Medical School of Naples is reported. Two different biotypes of S. marcescens with two completely different epidemiological patterns were identified. The prevalent biotype (A8b trigonelline-) was isolated in the delivery room, in the operating room, in the Nursery and in the NICU from items, healthy infant excreters and affected infants; the second biotype (A3a) was isolated only in the NICU from staff, two healthy infant excreters and two affected infants. Colonization of the throat and the gastrointestinal tract was frequent. Infected and colonized infants were the most important reservoir for serratia in the Nursery and in the NICU particularly for the type strain A3a. A mucus aspiration apparatus contaminated in the delivery room and the contamination of several instruments and items probably had a major role in the initiation and maintenance of the spread of the A8b strain. Mass contamination of the nursery has been related to overcrowding and a lack of the control measures; the transfer of high-risk colonized infants caused spread in the NICU. In the NICU the attack rate 26%; 69% of infants became ill; the case fatality ratio was 19%. Epidemiological investigation of the infants at risk showed some factors predisposing to infection with serratia. The hygienic measures failed to control the spread of serratia and it was necessary to refuse new admissions to pregnant women in order to decontaminate and re-organize the wards.
Topics: Anti-Bacterial Agents; Cross Infection; Disease Outbreaks; Enterobacteriaceae Infections; Feces; Humans; Infant, Newborn; Infant, Premature; Intensive Care Units, Neonatal; Italy; Microbial Sensitivity Tests; Nurseries, Hospital; Personnel, Hospital; Pharynx; Serratia marcescens; Skin
PubMed: 6379044
DOI: 10.1017/s0022172400060940 -
Journal of Applied Microbiology Oct 2017To evaluate the antibiofilm potential of water-soluble Moringa oleifera seed lectin (WSMoL) on Serratia marcescens and Bacillus sp.
AIMS
To evaluate the antibiofilm potential of water-soluble Moringa oleifera seed lectin (WSMoL) on Serratia marcescens and Bacillus sp.
METHODS AND RESULTS
WSMoL inhibited biofilm formation by S. marcescens at concentrations lower than 2·6 μg ml and impaired bacterial growth at higher concentrations, avoiding biofilm formation. For Bacillus sp., the lectin inhibited bacterial growth at all concentrations. The antibiofilm action of WSMoL is associated with damage to bacterial cells. WSMoL did not disrupt preformed S. marcescens biofilms but was able to damage cells inside them. On the other hand, the lectin reduced the number of cells in Bacillus sp. biofilm treated with it. WSMoL was able to control biofilm formation when immobilized on glass surface (116 μg cm ), damaging S. marcescens cells and avoiding adherence of Bacillus sp. cells on glass. The Bacillus sp. isolate is member of Bacillus subtilis species complex and closely related to species of the conspecific 'amyloliquefaciens' group.
CONCLUSION
WSMoL prevented biofilm development by S. marcescens and Bacillus sp. and the antibiofilm effect is also observed when the lectin is immobilized on glass.
SIGNIFICANCE AND IMPACT OF THE STUDY
Taking together, our results provide support to the potential use of WSMoL for controlling biofilm formation by bacteria.
Topics: Anti-Bacterial Agents; Bacillus; Biofilms; Lectins; Moringa oleifera; Plant Extracts; Seeds; Serratia marcescens
PubMed: 28792661
DOI: 10.1111/jam.13556 -
Journal of Clinical Microbiology Sep 2018is an environmental bacterium that is commonly associated with outbreaks in neonatal intensive care units (NICUs). Investigations of outbreaks require efficient...
is an environmental bacterium that is commonly associated with outbreaks in neonatal intensive care units (NICUs). Investigations of outbreaks require efficient recovery and typing of clinical and environmental isolates. In this study, we investigated how the use of next-generation sequencing applications, such as bacterial whole-genome sequencing (WGS) and bacterial community profiling, could improve outbreak investigations. Phylogenomic links and potential antibiotic resistance genes and plasmids in isolates were investigated using WGS, while bacterial communities and relative abundances of in environmental samples were assessed using sequencing of bacterial phylogenetic marker genes (16S rRNA and genes). Typing results obtained using WGS for the 10 isolates recovered during a NICU outbreak investigation were highly consistent with those obtained using pulsed-field gel electrophoresis (PFGE), the current standard typing method for this bacterium. WGS also allowed the identification of genes associated with antibiotic resistance in all isolates, while no plasmids were detected. Sequencing of the 16S rRNA and genes both showed greater relative abundances of at environmental sampling sites that were in close contact with infected babies. Much lower relative abundances of were observed following disinfection of a room, indicating that the protocol used was efficient. Variations in the bacterial community composition and structure following room disinfection and among sampling sites were also identified through 16S rRNA gene sequencing. Together, results from this study highlight the potential for next-generation sequencing tools to improve and to facilitate outbreak investigations.
Topics: Cross Infection; DNA, Bacterial; Disease Outbreaks; Electrophoresis, Gel, Pulsed-Field; Female; Genetic Markers; Genome, Bacterial; High-Throughput Nucleotide Sequencing; Humans; Infant; Infant, Newborn; Intensive Care Units, Neonatal; Male; Molecular Diagnostic Techniques; Quebec; Sequence Analysis, DNA; Serratia Infections; Serratia marcescens
PubMed: 29899005
DOI: 10.1128/JCM.00235-18