Aims: Marine bacteria have been reported to produce potential natural pigment with pharmaceutical properties and their growth can be manipulated in the laboratory to increase pigment production and their antimicrobial activity. Hence, this study aimed to enhance the prodigiosin production in Serratia marcescens IBRL USM84 by improving physical conditions. Methodology and results: The quantification of the pigment produced by S. marcescens IBRL USM84, bacterial cell growth, and its antibacterial activity in the broth medium were determined using a spectrophotometry method. Meanwhile, the antibacterial effect of red pigment on MRSA cells was observed under a scanning electron microscope (SEM). This marine isolate produced the highest yield of prodigiosin (6.95 μg/mL) when cultivated in marine broth with the addition of 0.2% of agar, 25 °C incubation temperature, initial medium pH of 7, 150 rpm of agitation speed for 48 h of cultivation time under light illumination. There was an increment of 151.81% in prodigiosin production after enhancement compared to before the enhancement of cultural conditions. SEM observations revealed that severe damage to the cell’s morphologies was exposed to red pigment as indicated by the formation of small dents, which led to completely collapse and eventually, cell death. Conclusion, significance and impact of study A positive correlation between pigment production and antibacterial activity was observed in the present study. The results supported the fact that marine bacteria are a reservoir of various pigments with antimicrobial properties. Also, the pigment production by S. marcescens and its antibacterial activity were significantly influenced by physical parameters.
Prodigiosin ; Serratia marcescens ; Marine Biology

Introduction: Nosocomial contaminants such as Pseudomonas aeruginosa and Serratia marcescens are increasingly developing resistance to many antibiotics. One of the promising alternatives that may complement, if not substitute, the use of antibiotics is quorum quenching, the process of interfering with chemical signals that mediate communication between microorganisms. Eleusine indica, a ubiquitous grass used traditionally to treat infections, has been shown to contain metabolites, such as fatty acid derivatives and p-coumaric acid, capable of quorum quenching. To date, there has been no study on the quorum quenching activity of E. indica.

Objectives: This study aimed to determine the in vitro activity of crude ethanolic extract of E. indica leaves against selected quorum-sensing regulated virulence factors of P. aeruginosa and S. marcescens.

Methodology: E. indica leaves were collected, washed, air-dried, and homogenized. Following ethanolic extraction and rotary evaporation, the extract was screened for antimicrobial activity through disk diffusion test and broth microdilution assay. The quorum quenching activity of the extract against P. aeruginosa was measured through swarming motility assay, while the activity against S. marcescens was measured through swarming motility and pigment inhibition assays. The quorum quenching assays were conducted in triplicates, and analysis of variance (ANOVA) was performed to identify differences among the treatment groups.

Results: Disk diffusion test revealed that no zones of inhibition formed against both P. aeruginosa and S. marcescens for varying concentrations of up to 200 mg/mL of the crude extract. Likewise, the MIC of the extract against both P. aeruginosa and S. marcescens was determined to be >200 mg/mL. However, it was shown that the extract, at 50 mg/mL, has statistically significant activity (p<0.05) against the swarming motility of P. aeruginosa, and it is 71.6% as effective in reducing the swarming area of the bacteria compared to cinnamaldehyde. This was not observed when the extract was tested against the swarming motility of and pigment production by S. marcescens.

Conclusion: In this study, the quorum quenching activity of the crude ethanolic extract of E. indica leaves was found to be effective against P. aeruginosa but not against S. marcescens. The compounds that will be identified by further studies may conceivably be used as an adjunct therapy in P. aeruginosa infections and as coating agents in medical devices.

Serratia marcescens is a recognized nosocomial opportunistic pathogen but rarely caused central nervous system infection especially in the neonates. Outbreaks have been documented in the neonatal intensive care units (NICU) and a higher incidence among those with surgical procedures. This review aims to describe a neonate with nonleaking lumbosacral myelomeningocele presenting with multiple pyogenic brain abscesses caused by S. marcescens admitted in a NICU. This review also presents a concise literature review discussing the potential risk factor involved, diagnostic measures and therapeutic possibilities. We present a neonate with Chiari II malformation admitted in the NICU developing S. marcescens ventriculitis after a lumbosacral myelomeningocele repair. With an empiric treatment of meropenem for one week, repeat ventricular cerebrospinal fluid analysis worsened and developed cerebral abscess as detected using cranial ultrasound. Ciprofloxacin was added and completed for six weeks with improved neurologic status. On a 6-month follow-up, sensorineural hearing loss, focal epilepsy and developmental delay were documented. A systematic review showed that prematurity and NICU outbreaks were among the most common risk factors for the central nervous system involvement of S. marcescens. Meropenem remains to be the antibiotic of choice adjunct with timely neurosurgical intervention. Brain abscess showed the worst prognosis among the neurologic sequelae.

Summary Cutaneous serratia marcescens (S. marcescens) infection is very rare and most cases had history of skin trauma or cutaneous procedure done before. It presents in various forms like non-healing ulcers, abscess formation, nodules with an intermittent course or as granulomatous lesions, thus mimicking non-infective lesions. Antibiotic choice is challenging due to multiple antibiotic resistant strains. We are reporting a case of cutaneous S. marcescens in a 70-year old lady with diabetes mellitus presented with non-healing ulcers over the dorsum of left hand for 6 months.
Serratia marcescens ; Dermatomycoses

Aims: Tryptamine is an amine compound derived from tryptophan by decarboxylation process. This compound can be found in fermented food and beverages, and in human gut and skin as well. This study aims to investigate the effect of tryptamine, on Gram-negative bacteria, namely Escherichia coli, Serratia marcescens and Pseudomonas aeruginosa. Methodology and results: In this study, we used E. coli, S. marcescens and P. aeruginosa due to their relatively observable quorum sensing-regulated phenotype, such as motility, prodigiosin and pyocyanin sequentially. Our results showed that tryptamine started to inhibit the growth and prodigiosin production of S. marcescens at concentration 250 μg/mL, while it inhibits the growth and pyocyanin production of P. aeruginosa at concentration 250 μg/mL and 500 μg/mL, respectively. Tryptamine inhibits both the growth and motility of E. coli at concentration 100 μg/mL. Conclusion, significance and impact of study These results suggest that tryptamine is able to inhibit the growth of E. coli, S. marcescens and P. aeruginosa at relatively high concentration, thus decreases the quorum sensing-regulated phenotypes. It implies that the growth and quorum sensing of Gram-negative bacteria most likely will not be affected by the low concentration of tryptamine that present in the gut.
Tryptamines ; Gram-Negative Bacteria ; Serratia marcescens ; Pseudomonas aeruginosa ; Escherichia coli

No abstract available.
Hidradenitis Suppurativa* ; Hidradenitis* ; Humans ; Serratia marcescens* ; Serratia* ; Skin*

BACKGROUND: Carbapenem-resistant Enterobacteriaceae (CRE) are increasingly being reported throughout the world, which is a significant problem for patient treatment and infection control. Carbapenem-resistance in Enterobacteriaceae is mainly due to carbapenem-hydrolyzing β-lactamase, which tends to spread through genetic mobile elements. Therefore, the detection of carbapenemase-producing Enterobacteriaceae (CPE) carriers is particularly important for the prevention and epidemiological monitoring of these infections. In this study, we performed surveillance cultures for CPE in patients admitted to the hospital and evaluated the prevalence of CPE. METHODS: Stool cultures were obtained from a total of 228 patients at our tertiary-care hospital between March and May 2017. Stool specimens were inoculated on ChromID CARBA agar (bioMérieux, France) and incubated for 18-24 hours. Suspicious colonies with pink or bluish-green color were screened for CPE by the modified Hodge test (MHT) and carbapenemase inhibition test (CIT). We performed PCR to detect five carbapenemase genes, bla(KPC), bla(IMP), bla(VIM), bla(NDM), and bla(OXA-48). RESULTS: Among 228 isolates, seven were suspicious for CPE: four Klebsiella pneumoniae, one Escherichia coli, one Enterobacter aerogenes, and one Serratia marcescens. Two K. pneumoniae isolates showed positive reactions in both the modified Hodge test and inhibition test with phenylboronic acid. By PCR, bla(KPC) was identified in these two K. pneumoniae isolates. CONCLUSION: Our results showed a very low prevalence (2/228, 0.9%) of CPE in our tertiary-care hospital based on surveillance culture in a recent three month period.
Agar ; Enterobacter aerogenes ; Enterobacteriaceae* ; Epidemiological Monitoring ; Escherichia coli ; Humans ; Infection Control ; Klebsiella pneumoniae ; Pneumonia ; Polymerase Chain Reaction ; Prevalence ; Serratia marcescens

OBJECTIVE: This study aimed to investigate the rates, types, and risk factors of surgical site infection (SSI) following intracranial neurosurgical procedures evaluated by a Korean SSI surveillance system.METHODS: This was a prospective observational study of patients who underwent neurosurgical procedures at 29 hospitals in South Korea from January 2017 to June 2017. The procedures included craniectomy, craniotomy, cranioplasty, burr hole, and ventriculoperitoneal shunt. Univariate and multivariate logistic regression analyses were performed.RESULTS: Of the 1576 cases included, 30 showed infection, for an overall SSI rate of 1.9%. Organ/space infection was the most common, found in 21 out of the 30 cases (70%). Staphylococcus aureus was the most common (41%) of all bacteria, and Serratia marcescens (12%) was the most common among gram-negative bacteria. In univariate analyses, the p-values for age, preoperative hospital stay duration, and over T-hour were <0.2. In a multivariate analysis of these variables, only preoperative hospital stay was significantly associated with the incidence of SSI (p < 0.001), whereas age and over T-hour showed a tendency to increase the risk of SSI (p=0.09 and 0.06).CONCLUSION: Surveillance systems play important roles in the accurate analysis of SSI. The incidence of SSI after neurosurgical procedures assessed by a national surveillance system was 1.9%. Future studies will provide clinically useful results for SSI when data are accumulated.
Bacteria ; Craniotomy ; Gram-Negative Bacteria ; Humans ; Incidence ; Korea ; Length of Stay ; Logistic Models ; Multivariate Analysis ; Neurosurgery ; Neurosurgical Procedures ; Observational Study ; Prospective Studies ; Risk Factors ; Serratia marcescens ; Staphylococcus aureus ; Surgical Wound Infection ; Ventriculoperitoneal Shunt

Spinal infection due to Serratia marcescens is very rare. A 78-year-old male patient withoutany risk factor was admitted to our hospital with chief complaints of severe back pain, fever, weakness in both legs, and bowel dysfunction, following caudal epidural injection. Magnetic resonance imaging revealed spondylodiscitis with epidural abscess. Surgical decompression was performed and the epidural abscess was removed. The cultures isolated S. marcescens, which can cause nosocomial infection in immunocompromised patient. However, to the best of our knowledge, we report the first case of S. marcescens spinal epidural abscess following epidural injection, with literature review.
Aged ; Back Pain ; Cross Infection ; Decompression, Surgical ; Discitis ; Epidural Abscess* ; Fever ; Humans ; Immunocompromised Host ; Injections, Epidural* ; Leg ; Magnetic Resonance Imaging ; Male ; Risk Factors ; Serratia marcescens* ; Serratia*

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.
Cefotaxime ; Ceftazidime ; Cephalosporins ; Citrobacter freundii ; Enterobacter ; Enterobacteriaceae* ; Morganella morganii ; Phenotype ; Serratia marcescens