Isolates Of Serratia Marcescens Research Articles

Extracellular Production of Pectinase from Bacteria Isolated from Rotten Apples from Lahore, Pakistan

Pectins are intricate blends of polysaccharides which make up around 33% of plantcell wall. Despite of their presence in the greater part of plant body and in other sources, commercial production of pectin is extremely difficult. This is a systematic study that aimed to produce pectinase from bacterial species isolated from rotten apple samples. Zymography and enzyme assay through DNS method were performed to check the pectinolytic activity of bacteria isolated from rotten apple samples. Of all five bacterial species (Serratia marcescens, Klebseilla pneumoniea, Pseudomonas aeruginosa and Escherichia coli) maximum enzyme concentration was showed in Pseudomonas aeruginosa and it was 6.2 U/mL. The major achievement of this study was to screen out the most efficient pectinases producing isolate of Serratia marcescens from rotten apples that has never been reported to produce pectinase, previously.

Potential of five non-spore-forming bacteria, originated from the European cockchafer, Melolontha melolontha (Linnaeus, 1758) (Coleoptera: Scarabaeidae), on three economic insect pests

Five non-spore-forming bacteria were isolated from the European cockchafer, Melolontha melolontha (Linnaeus, 1758) (Coleoptera: Scarabaeidae). Their potential was tested against the three economic insect pests, the great spruce bark beetle, Dendroctonus micans Kugelann (Coleoptera: Curculionidae); the pine processionary, Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae); and the gypsy moth, Lymantria dispar (Linn.) (Lepidoptera: Erebidae), to find an effective biological control agent. All isolated bacteria were cultured and identified using VITEK bacterial identification systems and 16S rRNA gene sequence analysis. The bacteria were identified as Enterobacter cloacae complex (isolate 1M), Serratia marcescens (isolate 3M), Pseudomonas aeruginosa (isolate 4M), Kocuria kristinae (isolate 5M), and Serratia liquefaciens (isolate 8M). Laboratory experiments, carried out to evaluate the virulence of these isolates, showed that all isolated bacteria had a pathogenic effect on the tested pests. E. cloacae had 35, 56.7, and 84%; S. marcescens 50, 60.9, and 47.8%; P. aeruginosa 55, 69.6, and 48%; K. kristinae 40, 43.5, and 16%; and S. liquefaciens 45, 65.2, and 36% mortality rates on the larvae of D. micans, T. pityocampa, and L. dispar, respectively. The isolated bacteria can be considered in integrated pest control programs.

Purification and characterization of a metalloprotease produced by the C8 isolate of Serratia marcescens using silkworm pupae or casein as a protein source

Serratiopeptidase, a metalloprotease produced by Serratia marcescens, is produced through a fermentation process using carbohydrates and proteins as carbon and nitrogen sources. However, some byproducts of the silk industry could be an alternative source for serratiopeptidase production. Therefore, the present work is focused on the purification and characterization of a serratiopeptidase produced from the C8 isolate of Serratia marcescens and obtained from a Colombian silkworm hybrid using casein or silkworm pupae. The protease was purified using ultrafiltration, anion-exchange, and size-exclusion chromatography. The purified enzyme showed a molecular weight of ~50 kDa with a purity above 96%, an isoelectric point of ~4.6, optimum pH and temperature of 6 and 50 °C, and stability at 4 °C for one month. The kinetic constants using azocasein as substrate were 0.63 mM (Km), 2,016 μM/min (Vmax), 41.41 s−1 (Kcat), and 6.56 × 107 M−1 s−1 (Kcat/Km). Inhibition by 5 mM EDTA or 1,10-phenanthroline was recovered by adding Zn2+ at the same concentration. Mass spectrometry analysis indicated 94% homology with the sequence of serratiopeptidase produced by the E-15 strain. We purified and characterized a serratiopeptidase produced by the C8 isolate of S. marcescens in a culture medium based on a renewable source from the silk industry.

Synergistic Effect of Ceftazidime-Avibactam with Meropenem against Panresistant, Carbapenemase-Harboring Acinetobacter baumannii and Serratia marcescens Investigated Using Time-Kill and Disk Approximation Assays.

Susceptibility of ceftazidime-avibactam and in vitro synergy with meropenem were investigated using disk approximation and time-kill assays against 11 multiresistant Acinetobacter baumannii isolates harboring oxacillinases and 5 Serratia marcescens isolates carrying blaKPC-2 Ceftazidime-avibactam was very active and synergistic with meropenem against multiresistant S. marcescens isolates. On the other hand, only the A. baumannii isolates coharboring blaOXA-23 and blaOXA-117 displayed synergy. The disk approximation technique presented good sensitivity for synergism in S. marcescens infection.

Classical and Statistical Optimization of Medium Composition for Promoting Prodigiosin Produced by Local Isolate of Serratia Marcescens

Prodigiosin is a ‘natural red pigment produced by Serratia marcescens which exhibits immunosuppressive and anticancer properties in addition to antimicrobial activities. This work presents an attempt to maximize the production of prodigiosin by two different strategies: one factor at time (OFAT) and statistical optimization. The result of OFAT revealed that sucrose and peptone were the best carbon and nitrogen sources for pigment production with concentration of prodigiosin of about 135 mg/ L. This value was increased to 331.6mg/ L with an optimized ratio of C/N (60:40) and reached 356.8 with pH 6 and 2% inoculum size at end of classical optimization. Statistical experimental design based on Response surface methodology was conducted to optimize the composition of trace element. The design revealed that the predicted prodigiosin production of 406 mg/L can be achieved when concentrations of trace element CaCl2·2H2O, FeSO4·4H2O, MgSO4·7H2O and MnSO4·4H2O were equal to 9.22, 0.32, 0.67 and 2.48 g/L, respectively. The actual production of prodigiosin in the optimized medium was 375 mg/L. Growth kinetics of S. marcescens were evaluated in optimized medium which revealed that prodigiosin was ‘non-associated growth’ secondary metabolite with maximum production of approximately 365.7 mg/L obtained after 54 hours of incubation.

Production and Partial Purification of Tannase from Serratia Marcescens Isolated from Different Sources

Tannase has different benefits in food, chemical and pharmaceutical fields. Seventeen Serratia marcescens isolates were collected from septicemia, wound infections and hospital environment(babies incubators).These isolates were identified by biochemical tests and Vitek 2 system that contained Vitek GNI card then conformed by16S rRNA gene products(amplified size 179 bp) for genotypic detection. After that, they screened for higher tannase production and Serratia marcescens b9 was a better producer of tannase with a larger diameter of a dark green zone. The tannase activity was increased to 63U/ml when this isolate was cultivated under the optimal conditions which consisted of using nutrient broth supplemented with ber leaves at pH value 5.5 and a temperature equals to 37°C for 72 hours. In the partial purification of tannase, ammonium sulfate was more efficient than organic solvents, since it was found that 70% saturation of ammonium sulfate led to precipitate of tannase with tannase activity of 80U/ml. In contrast, 30% of ethanol, acetone, and isopropanol led to precipitate of tannase with different levels of activity ranged between 45-47U/ml. Consequently, ber leaves have a potential as an effective and much cheaper (economical) substrate for tannase production in comparison with traditionally used substrates like tannic acid.

Isolation and Identification of Serratia marcescens from Suspected Late Neonatal Sepsis in Intensive Care Unit

Background: Neonatal sepsis stays one of the main sources of morbidity and mortality both among infant in ICU, in light of the planning of the disease neonatal sepsis has been categorized into early and late-onset sepsis, where the latter occurs after one week of life and is often more insidious in onset than the former. Objective: To detect the rate of Serratia marcescens infection in neonatal sepsis in ICU by molecular technique. Methods: A total of 50 neonates with the age group 8 days to 30 days who were admitted to AL-Kadhumiya Teaching Hospital/ Baghdad during the period January to March ,2017 were recruited for this cross-sectional study. Approximately 3 ml of venous blood were obtained from each patients. These samples were examined for septicemia by blood culturing followed by API20 for quick identification of relevant bacteria. Furthermore, bacteria DNA was isolated directly from blood samples, and conventional PCR based on luxS gene, highly specific to S. marcescens, was achieved. Results: Blood culture were positive in 36(72 %) out of 50 samples; the most common bacterial causes were Staphylococcus aureus (18.7%), Pseudomonas aeruginosa (13.8%) and Serratia marcescens (11.1%), Molecular method revealed specific amplification of luxS gene in 12 samples (24%). Conclusion: Serratia marcescens has risen as a most widely recognized causative agent in late onset sepsis.

Survival of antibiotic resistant bacteria following artificial solar radiation of secondary wastewater effluent

Urban wastewater treatment plant effluents represent one of the major emission sources of antibiotic-resistant bacteria (ARB) in natural aquatic environments. In this study, the effect of artificial solar radiation on total culturable heterotrophic bacteria and ARB (including amoxicillin-resistant, ciprofloxacin-resistant, rifampicin-resistant, sulfamethoxazole-resistant, and tetracycline-resistant bacteria) present in secondary effluent was investigated. Artificial solar radiation was effective in inactivating the majority of environmental bacteria, however, the proportion of strains with ciprofloxacin-resistance and rifampicin-resistance increased in the surviving populations. Isolates of Pseudomonas putida, Serratia marcescens, and Stenotrophomonas maltophilia nosocomial pathogens were identified as resistant to solar radiation and to at least three antibiotics. Draft genome sequencing and typing revealed isolates carrying multiple resistance genes; where S. maltophilia (resistant to all studied antibiotics) sequence type was similar to strains isolated in blood infections. Results from this study confirm that solar radiation reduces total bacterial load in secondary effluent, but may indirectly increase the relative abundance of ARB.

Isolation and characterisation of virulent Serratia marcescens associated with a disease outbreak in farmed ornamental fish, Poecilia reticulata in Kerala, India

Pathogenic strain of Serratia marcescens (NPSM-1) with multiple drug resistance was isolated from guppy Poecilia reticulata with clinical signs of fin rot and was confirmed by biochemical tests and 16S rRNA gene sequencing. The extra cellular proteins (ECP) of the bacteria exhibited marked cytotoxic activity in vitro on Cyprinus carpio koi fin (CCKF) cell line. The in vivo challenge studies confirmed that the isolate was highly pathogenic to fish when the fishes were injected with1 x 104 CFU/fish and the same bacterium was re-isolated from infected fish, post-challenge. S. marcescens produced large zones of haemolysis on 10% sheep blood agar. The bacteria was found to carry virulence genes; extracellular metalloprotease gene (Pr596) and AHL synthase gene (SpnI). The bacterial isolate was tested to determine sensitivity against 16 antibiotics and was sensitive to only 5 viz., cefixime, chloramphenicol, ciprofloxacin, gentamycin and erythromycin. The study indicates that S. marcescens can cause disease in ornamental fish and the bacterium being a known human pathogen, may also cause infections in humans having direct contact with infected fishes. This is the first report describing S. marcescens as a pathogen of freshwater ornamental fish in India.

Synthesis and characterization of nanoparticles conjugated tannase and using it for enhancement of antibacterial activity of tannase produced by Serratia marcescens

Fourteen isolates of Serratia marcescens were collected from patients suffering from septicemia. All theseisolates revealed different levels in tannase production. Tannase was partially purified from Serratia marcescens b9 by precipitation method at 70% saturation of ammonium sulfate. Au, Pt, SnO2 and SiO2 nanoparticles were prepared by laser ablation and examined by transmission electron microscopy (TEM), X-ray diffraction pattern and UV-Visible absorption spectroscopy. Conjugation of SiO2 nanoparticles to tannase by feeding and pulses methods were prepared and characterized by TEM, X-ray diffraction pattern and UV-Visible spectrum. SiO2 nanoparticles conjugated partially purified tannase by feeding showed the higher effectiveness and higher significant level against all tested UTI causing in comparison with ciprofloxacin antibiotic, SiO2 nanoparticles alone, partially purified tannase alone and partially purified tannase by pulses. So that we can conclude that feeding method was the best method for enhancement partially purified tannase activity to maximum level thus SiO2 nanoparticles conjugated partially purified tannase may be a useful antibacterial agent for the treatment of urinary tract infection.

Isolation of Serratia marcescens involved in chitin degradation in the bulb mite Rhizoglyphus robini

There is an increasing awareness of the importance of the microbiome of arthropods to understand their host’s biology. In the bulb mite, Rhizoglyphus robini, associated bacteria have been found to be involved in its chitinolytic abilities. The bulb mite, a plant pest feeding on below-ground parts of mostly Liliaceae crops, prefers fungus-infested plants. Moreover its fitness is higher when feeding on a fungal food source than when feeding on non-infected plants. In this study we isolated a chitinolytic bacterium from mite homogenate and identified it molecularly as Serratia marcescens (Bizio 1823), which is a model organism for chitin degradation. Precise identification of the bacterium can be important for the development of biological control programs of the mite as well as for further studies investigating Serratia marcescens and its chitinolytic machinery.

SlpE is a calcium-dependent cytotoxic metalloprotease associated with clinical isolates of Serratia marcescens

Serralysin-like proteases are found in a wide variety of bacteria. These metalloproteases are frequently implicated in virulence and are members of the widely conserved RTX-toxin family. We identified a serralysin-like protease in the genome of a clinical isolate of Serratia marcescens that is highly similar to the canonical serralysin protein, PrtS. This gene was named serralysin-like protease E, SlpE, and was found in the majority (67%) of tested clinical isolates, but was absent from most tested non-clinical isolates including the insect pathogen and reference S. marcescens strain Db11. Purified recombinant SlpE exhibited calcium-dependent protease activity similar to metalloproteases PrtS and SlpB. Induction of slpE in the low-protease-producing S. marcescens strain PIC3611 highly elevated extracellular protease activity, and extracellular secretion required the lipD type 1 secretion system gene. Transcription of slpE was highly reduced in an eepR transcription factor mutant. Mutation of the slpE gene in a highly proteolytic clinical isolate reduced its protease activity, and evidence suggests that SlpE confers cytotoxicity of S. marcescens to the A549 airway carcinoma cell line. Together, these data reveal SlpE to be an EepR-regulated cytotoxic metalloprotease associated with clinical isolates of an important opportunistic pathogen.

Impact of Revised Broad-Spectrum Cephalosporin Clinical and Laboratory Standards Institute Breakpoints on Susceptibility in Enterobacteriaceae Producing AmpC β-Lactamase.

We evaluated the impact of revised Clinical and Laboratory Standards Institute (CLSI) breakpoints for broad-spectrum cephalosporins (BSCs) on the susceptibilities of 1,742 isolates of Enterobacter species, Serratia marcescens, Citrobacter freundii, and Morganella morganii. The 2011 CLSI criteria for cefotaxime and ceftazidime reduced the rates of susceptibility by 2.9% and 5.9%, respectively. The 2014 CLSI criteria for cefepime reduced the rate of susceptibility by 13.9%, and categorized 11.8% isolates as susceptible-dose dependent (SDD) for cefepime. Among 183 isolates with extended-spectrum ß-lactamase (ESBL) phenotype, implementation of the new criteria reduced the rates of susceptibility to cefotaxime, ceftazidime, and cefepime by 2.8%, 14.8%, and 53.6%, respectively. The proportion of ESBL phenotype among BSC-susceptible isolates was low (0.9% for cefotaxime, 3.0% for ceftazidime, and 3.3% for cefepime). In summary, implementation of new CLSI criteria led to little change in susceptibility to cefotaxime and ceftazidime but a substantial change in susceptibility to cefepime. The recognition of revised CLSI criteria for BSC and SDD will help clinicians to select the optimal antibiotic and dosing regimen.

Emergence of Serratia marcescens isolates possessing carbapenem-hydrolysing β-lactamase KPC-2 from China

Eighty-three carbapenem-resistant Serratia marcescens isolates were recovered from Zhejiang Provincial People's Hospital, China. The minimum inhibitory concentrations of imipenem, meropenem, and ertapenem for all isolates were 2 to >128μg/mL. Polymerase chain reaction indicated that 63 S.marcescens isolates produced Klebsiella pneumoniae carbapenemase (KPC)-2. Clone A (15 isolates) and clone B (41 isolates) were the two dominant clones and clone A strains were gradually replaced by clone B strains between 2011 and 2014. The results indicate that blaKPC-2-positive S.marcescens emerged in our hospital as the major mechanism of carbapenem resistance.

Optimal Conditions Measured for Production of Prodigiosin from Serratia marcescens Bacteria Isolated from Different Sources

Selected optimal conditions for production of prodgiosin for pathological and environmental isolates of the bacterium Serratia marcescens which was isolated from pathological and environmental sources, the results showed that the peanut powder medium at 2% concentration was the highest production of pigment under the conditions of pH 8, volume 50 ml from the medium in 250 ml conical flask at 28 ºC for 72 hrs without light.

60 Serratia marcescens: An emerging pathogen or innocent bystander?

Objective Serratia marcescens (SM) is a Gram-negative organism which is known to cause hospital-acquired infections. Its incidence in CF lung infections is low and as such determining its effect on CF disease is difficult. This study aimed to examine risk factors for acquisition of SM and the clinical effect of infection. Methods A retrospective review of case notes of all patients who isolated SM in the years 2008–14 was made in a single adult CF centre. Data was compared with controls matched for age, sex and lung function. Results 14 patients had at least one isolate of SM over the study period. Five were single isolates, 3 had intermittent isolates and 6 were chronically infected. Median age (IQR) at isolation was 24 yrs (16.8–32.5). Eight were male. Median FEV 1 at isolation was 2.1 L (1.3–2.6), median FEV 1 % predicted was 52% (30–81). No significant differences between cases and controls(n = 28) at first isolation were seen for the rates of pancreatic insufficiency, CF-related diabetes, ABPA or CF-related diabetes. Equally no differences were seen in the rates of use of mucolytics, inhaled/oral antibiotics or steroid use. A comparison of spirometry revealed no differences in FEV 1 between controls, single isolates and intermittent/chronic infection in the 2 years following infection. Conclusion In this small single-centre study, no significant risk factors for the isolation of SM were seen. Furthermore, isolation of SM had no significant effect on lung function. Specific inclusion of SM infection in CF registries will allow larger studies to determine whether this organism is truly pathogenic.

Pathogenicity of Isolates of Serratia Marcescens towards Larvae of the Scarab Phyllophaga Blanchardi (Coleoptera).

Serratia marcescens is a Gram negative bacterium (Enterobacteriaceae) often associated with infection of insects. In order to find pathogenic bacteria with the potential to control scarab larvae, several bacterial strains were isolated from the hemocoel of diseased Phyllophaga spp (Coleoptera:Scarabaeidae) larvae collected from cornfields in Mexico. Five isolates were identified as Serratia marcescens by 16S rRNA gene sequencing and biochemical tests. Oral and injection bioassays using healthy Phyllophaga blanchardi larvae fed with the S. marcescens isolates showed different degrees of antifeeding effect and mortality. No insecticidal activity was observed for Spodoptera frugiperda larvae (Lepidoptera: Noctuidae) by oral inoculation. S. marcescens (Sm81) cell-free culture supernatant caused significant antifeeding effect and mortality to P. blanchardi larvae by oral bioassay and also mortality by injection bioassay. Heat treated culture broths lost the ability to cause disease symptoms, suggesting the involvement of proteins in the toxic activity. A protein of 50.2 kDa was purified from the cell-free broth and showed insecticidal activity by injection bioassay towards P. blanchardi. Analysis of the insecticidal protein by tandem- mass spectrometry (LC-MS/MS) showed similarity to a Serralysin-like protein from S. marcescens spp. This insecticidal protein could have applications in agricultural biotechnology.

Homology analysis of Serratia marcescens strains causing blood stream infection in an intensive care unit

Objective To provide the guidance for the control and treatment of blood stream infection caused by Serratia marcescens strains through analyzing the homology and drug resistant genes of the isolates collected from the Intensive Care Unit (ICU) of Shaoxing County Central Hospital. Methods Serratia marcescens strains were isolated from ICU patients with blood stream infection and also from the hands of health care providers in the ICU from June 1st to September 30th, 2013. The antibiotic susceptibilities of the Serratia marcescens isolates were tested. PCR was performed to amplify the common drug resistant genes. Pulse-field gel electrophoresis (PFGE) was carried out for analyzing the homology of all isolates. The complete clinical data of the patients were collected and statistically analyzed with Spearman′s rank correlation coefficient. Results Seventeen strains were isolated in this study. All of the 17 strains were resistant to the first and second generation Cephalosporin, Gentamicin and Ciprofloxacin, and sensitive to Amikacin and Ceftazidime. The drug resistant rates to Carbapenems ranged from 11.76% to 35.29%. One of the isolates (5.88%) carried the TEM gene. The results of PFGE showed that the phenotypes of all isolates were identical. Conclusion Serratia marcescens strains were critical hospital infectious pathogens. They were able to spread in the hospital and were resistant to multiple antibiotics. Clinical physicians should properly use antibiotics for the patients based on the result of drug susceptibility test. A control regulation for Serratia marcescens infection within hospital should be enforced to avoid the cross infection and the outbreak of resistant strains. Key words: ICU; Serratia marcescens; Homology; Drug resistance

Serratia marcescens outbreak in a neonatal intensive care unit: crucial role of implementing hand hygiene among external consultants.

BackgroundSerratia marcescens represents an important pathogen involved in hospital acquired infections. Outbreaks are frequently reported and are difficult to eradicate. The aim of this study is to describe an outbreak of Serratia marcescens occurred from May to November 2012 in a neonatal intensive care unit, to discuss the control measures adopted, addressing the role of molecular biology in routine investigations during the outbreak.MethodsAfter an outbreak of Serratia marcescens involving 14 neonates, all admitted patients were screened for rectal and ocular carriage every two weeks. Extensive environmental sampling procedure and hand sampling of the staff were performed. Antimicrobial susceptibility pattern and molecular analysis of isolates were carried out. Effective hand hygiene measures involving all the external consultants has been implemented. Colonized and infected babies were cohorted. Dedicated staff was established to care for the colonized or infected babies.ResultsDuring the surveillance, 65 newborns were sampled obtaining 297 ocular and rectal swabs in five times. Thirty-four Serratia marcescens isolates were collected: 11 out of 34 strains were isolated from eyes, being the remaining 23 isolated from rectal swabs. Two patients presented symptomatic conjunctivitis. Environmental and hand sampling resulted negative. During the fifth sampling procedure no colonized or infected patients have been identified. Two different clones have been identified.ConclusionsOcular and rectal colonization played an important role in spread of infections. Implementation of infection control measures, involving also external specialists, allowed to control a serious Serratia marcescens outbreak in a neonatal intensive care unit.

PMQR determinants among clinical isolates of ESBL and Amp C producing Serratia marcescens in Mansoura University Hospitals: A six year study

Background: Plasmid mediated quinolone resistant determinants (PMQR) are found to be of clinical relevance because it causes decreased quinolones sensitivity. Quinolones are valuable antibiotics against intrinsically resistant Serratia marcescens. Purpose: To determine the occurrence of PMQR determinants qnr, aac(6′)-Ib-cr and qep and their relation with extended-spectrum β-lactamase (ESBL) and / or Amp C- producing Serratia marcescens. Material and Method: One hundred and eleven Serratia marcescens were tested for resistance to five quinolones by disc diffusion method. Testing for qnr, aac(6′)-Ib-cr and qep was carried by multiplex PCR. Whereas ESBL and Amp C production were evaluated by double disc synergy test and cefoxitin Hodge test respectively. Results: Out of 111 Serratia marcescens , 51 (45.9%) were resistant to one or more of the used quinolones. Among Serratia marcescens isolates, 13 (11.7%) were ESBL producers while 5 (4.5%) were Amp C producers. Multiplex PCR confirmed the presence of PMQR determinant in 14 (12.6%) isolates of Serratia marcescens. Serratia marcescens positive for qnr determinants were detected as qnrA and qnr B in 3 and 10 isolates respectively whereas one isolate co harbored aac(6')-Ib-cr and qnrA. Among 13 ESBL producers, 3 and 5 isolates were positive for qnrA and qnr B respectively (8/13, 61.5%). Whereas one isolate co- expressed aac(6')-Ib-cr and qnrA was associated with Amp C production (1/5, 20%). Conclusion: This study indicated that PMQR play significant role in the occurrence and expansion of fluoroquinolone resistance in Serratia macrscens. Moreover they are closely associated with ESBL and Amp C producers.