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PubMed2026

Antimicrobial Resistance in Nontyphoidal Salmonella and Clinically Relevant Enterococcus From Faecal Samples of Conservation-Priority Captive Ungulates in a United Arab Emirates Urban Zoo: A Cross-Sectional Baseline Study.

Antimicrobial resistance (AMR) is a One Health challenge driven by microbial exchange among humans, animals and the environment. Zoological institutions offer useful settings for environmental AMR surveillance. This single-zoo cross-sectional study examined the occurrence, antimicrobial susceptibility and genomic characteristics of nontyphoidal Salmonella enterica (NTS) and clinically relevant Enterococcus spp. in faecal samples from 101 clinically healthy captive ungulates representing seven conservation-priority species at a major urban zoo in the United Arab Emirates. NTS was detected in 4/101 samples (3.9%), including serovars Schwarzengrund (n = 2), Kentucky (n = 1) and Chester (n = 1). Among the four recovered NTS isolates, all met the study MDR definition within the tested panel, including a Salmonella Kentucky ST198 isolate carrying multiple resistance genes and quinolone-associated mutations. Enterococcus spp. were detected in 77/101 samples (76.2%), dominated by Enterococcus faecium and Enterococcus casseliflavus (each 41.5%). Among 33 E. faecium/Enterococcus faecalis isolates tested phenotypically, resistance was generally low, with erythromycin and ciprofloxacin resistance each observed in 9.1%. One clinically important E. faecium isolate showed glycopeptide resistance and genetic markers associated with reduced daptomycin susceptibility. These single-institution cross-sectional data provide an initial regional baseline for AMR-relevant enteric bacteria in conservation-managed ungulates and identify priorities for broader longitudinal and interface-based surveillance.

Animals↗

PubMed2025

Multidrug resistance and recurrence in urinary bacteraemia among cancer patients.

BACKGROUND: Urinary tract infections (UTI) in oncological patients can lead to bacteraemia (bUTI), increasing morbidity and mortality. This study assessed the characteristics, outcomes and recurrence of bUTI in oncological patients. METHODS: A retrospective cohort study was conducted at Hospital Clinic, Barcelona, from 2008 to 2019. All episodes of bUTI in oncological patients were analysed. Multivariable regression models identified independent risk factors for multidrug-resistant (MDR) Gram-negative bacilli (GNB), recurrent bUTI and related mortality. RESULTS: A total of 561 bUTI episodes were identified in 478 oncological patients. Urinary tract involvement due to neoplasm was present in 62.2%, and 59.4% had urinary tract instrumentation. Prior UTI-related admission without bacteraemia was reported in 63.8%. Following bUTI, oncological treatment was delayed in 47% and stopped in 33.6% of cases. GNB caused 87.3% of episodes, with Escherichia coli and Klebsiella spp. being the most common pathogens. Enterococcus spp. and Pseudomonas aeruginosa were frequent, particularly in patients with urinary instrumentation. MDR-GNB caused 19.6% of episodes, and 23.4% of cases received inappropriate empirical antibiotic therapy (IEAT). Recurrent bUTI occurred in 14.0% of patients. A simple predictive score efficiently identified patients at high risk of recurrence. Thirty-day mortality was 15.3%, and bUTI-related mortality was 10.7%, with absence of fever, septic shock and carbapenemase-producing Enterobacterales linked to higher related mortality. CONCLUSION: bUTI in oncological patients is predominantly caused by GNB, with high rates of MDR isolates and high mortality. IEAT is common, and recurrence is significant, highlighting the need for targeted preventive strategies and optimized empirical therapy.

Humans↗

PubMed2026

Dual-species interactions with intestinal bacteria drive multi-drug resistance in Campylobacter.

OBJECTIVES: Multidrug-resistant (MDR) Campylobacter infections are an increasing clinical concern, as rising fluoroquinolone (FQ) resistance leaves macrolides as the primary treatment option. We investigated multidrug resistance in clinical Campylobacter samples from Germany. METHODS: We analyzed 6980 clinical isolates (2010-2022), performing phenotypic susceptibility testing and sequencing on 2912 genomes. Cultures showing multidrug resistance were studied using scanning electron microscopy (SEM). RESULTS: We found that 453 (6%) Campylobacter samples were resistant to both FQ and macrolides. Two of the C. jejuni samples were resistant to antibiotics from ten different classes. Genome analysis revealed that these samples, despite being derived from single colonies, contained >10% Enterococcus DNA reads. SEM confirmed the presence of coccoid bacteria interspersed with spiral-shaped Campylobacter. Additional culture-based purification resulted in pure C. jejuni isolates that retained FQR but lost macrolide resistance. The presence of MDR Enterococcus spp. in the mixed samples protected C. jejuni from above-MIC (minimum inhibitory concentration) concentrations of several ribosome-targeting antimicrobials whereas pure Campylobacter were susceptible. CONCLUSIONS: The impact of microbial interactions on resistance phenotypes is poorly understood. We show that close interactions with highly resistant intestinal bacteria can induce multidrug resistance phenotypes in Campylobacter. These findings highlight that microbial context shapes antibiotic resistance and may influence treatment outcomes.

Campylobacter jejuni↗

PubMed2025

In vitro and in vivo efficacy of vancomycin against Elizabethkingia species and the impact of increased vancomycin MICs.

UNLABELLED: This study aimed to evaluate the concordance of vancomycin susceptibility testing methods, its in vivo and in vitro efficacy, and the mechanisms underlying elevated MICs in Elizabethkingia spp. Vancomycin susceptibilities of 18 E. anophelis isolates were determined using multiple assays. The efficacy of vancomycin against five clinical isolates and one laboratory-induced mutant with an elevated vancomycin MIC was evaluated using time-kill assays and Galleria mellonella and murine models. Vancomycin MICs (16-32 mg/L) determined by broth microdilution were consistent with agar dilution, Etest, and MBC assay results. All isolates had zone diameters < 17 mm and were, thus, categorized as non-susceptible according to the CLSI criteria for Enterococcus spp. Time-kill assays of five clinical isolates demonstrated that vancomycin at a clinically relevant concentration (4 mg/L) exhibited poor bactericidal activity similar to that of teicoplanin. Vancomycin improved Galleria mellonella survival in a dose-dependent manner, whereas teicoplanin, dalbavancin, oritavancin, and daptomycin were ineffective. Murine models revealed that vancomycin at a human-equivalent dose (25 mg/kg twice daily) prolonged survival in most infections and modestly reduced bacterial load, while teicoplanin remained ineffective. Vancomycin efficacy was significantly reduced in G. mellonella and mice infected with a mutant strain exhibiting an elevated MIC (128 mg/L), which was attributable to spontaneous mutations in pbp4. In conclusion, E. anophelis were consistently non-susceptible to vancomycin as determined by multiple in vitro assays. However, vancomycin demonstrated unique in vivo activity among glycopeptides although this effect was abrogated by spontaneous mutations leading to elevated MICs. IMPORTANCE: Elizabethkingia anophelis is a multidrug-resistant pathogen associated with limited treatment options and high mortality. Most commonly considered agents, including fluoroquinolones, piperacillin/tazobactam, and trimethoprim/sulfamethoxazole, are increasingly compromised by resistance, toxicity, or inconsistent efficacy. Although vancomycin is not routinely used for Gram-negative infections due to limited outer membrane permeability, case reports have suggested potential benefit in Elizabethkingia infections under critical conditions. In this study, we show that E. anophelis isolates are uniformly non-susceptible to vancomycin in vitro and exhibit minimal bactericidal activity. However, vancomycin conferred a modest but statistically significant survival benefit in two independent animal models. Importantly, this effect was lost in strains with vancomycin-induced MIC elevation, and genome analysis identified pbp4 mutations as a potential underlying mechanism. These findings suggest vancomycin may offer therapeutic benefit when no preferred options are available. They support cautious use in selected cases and highlight the need for continued monitoring of susceptibility and resistance development.

Vancomycin↗

PubMed2025

Antibody responses in Klebsiella pneumoniae bloodstream infection: a prospective cohort study.

BACKGROUND: Klebsiella pneumoniae is a leading cause of infection-related deaths globally, yet little is known about human antibody responses to invasive K pneumoniae. We sought to determine whether the O-specific polysaccharide antigen is immunogenic in humans with K pneumoniae bloodstream infection. We also sought to define the cross-reactivity of human antibody responses among structurally related K pneumoniae O-specific polysaccharide subtypes and to assess the effect of capsule production on O-specific polysaccharide-targeted antibody binding and function. METHODS: In this prospective cohort study, we compared plasma antibody responses to O-specific polysaccharide in a cohort of consecutively enrolled patients with K pneumoniae bloodstream infection with controls, specifically a cohort of healthy individuals and a cohort of individuals with Enterococcus spp bloodstream infection. Patients were enrolled at the Massachusetts General Hospital, a tertiary hospital with affiliated clinics in the USA. We excluded patients whose isolates were not confirmed to be K pneumoniae by whole-genome sequencing. The primary outcome was the measurement of plasma IgG, IgM, and IgA antibody responses. We performed flow cytometry to measure the effects of K pneumoniae capsule production on O-specific polysaccharide antibody binding and O-specific polysaccharide antibody-mediated complement deposition, using patient isolates with variable levels of capsule production and isogenic capsule-deficient strains derived from these isolates. FINDINGS: We enrolled 129 consecutive patients with suspected K pneumoniae bloodstream infection between July 24, 2021, and August 4, 2022, of whom 69 patients (44 [64%] male and 25 [36%] female) with confirmed K pneumoniae bloodstream infection were eligible for immunological evaluation. Common O-specific polysaccharide serotypes (O1, O2, O3, and O5) accounted for 57 (83%) of 69 infections. O-specific polysaccharide was immunogenic in patients with K pneumoniae bloodstream infection, and peak O-specific polysaccharide-IgG antibody responses in patients were ten-fold to 30-fold higher than antibody responses detected in healthy controls, depending on the serotype. There was cross-reactivity among similar O-specific polysaccharide subtypes, including the O1v1 and O1v2, O2v1 and O2v2, and O3 and O3b subtypes, as well as between the O1 and O2 types. Capsule produced by both hyperencapsulated and non-hyperencapsulated K pneumoniae inhibited O-specific polysaccharide-targeted antibody binding and function. INTERPRETATION: O-specific polysaccharide was immunogenic in patients with K pneumoniae bloodstream infection, supporting its potential as a candidate vaccine antigen. The cross-reactivity observed between similar O-specific polysaccharide subtypes in patients with K pneumoniae bloodstream infection suggests that it might not be necessary to include all subtypes in an O-specific polysaccharide-based vaccine. However, these observations are tempered by the fact that capsule production, even in non-highly encapsulated strains, has the potential to interfere with O-specific polysaccharide antibody binding. This finding could limit the effectiveness of vaccines that exclusively target O-specific polysaccharide. FUNDING: National Institute of Allergy and Infectious Diseases at the National Institutes of Health.

Humans↗

PubMed1978

Diffusion disk susceptibility testing with cefaclor.

The reliability of the standardized 30-mug cephalothin disk and that of an experimental 30-mug cefaclor disk in predicting probable clinical susceptibility to cefaclor were compared. Quantitative determinations of cefaclor susceptibility were measured by the World Health Organization International Collaborative Study agar dilution procedure; diffusion disk tests were performed by the standardized U.S. Food and Drug Administration disk test. The cephalothin disk erred in predicting probable susceptibility in 52% of isolates of Enterococcus spp. resistant to 16 mug or less of cefaclor per ml; the cefaclor disk did not. The cephalothin disk erred in correctly predicting susceptibility in only 20% of cefaclor-susceptible isolates of Enterobacter spp.; the cefaclor disk correctly predicted susceptibility for 70%. These results indicate the need for further evaluation of a separate cefaclor disk for use in susceptibility testing with this new cephalosporin.

Cephalosporins↗

PubMed2026

Antimicrobial susceptibility patterns of commensal fecal bacteria isolated from pigs with an intentional genomic alteration that included the selectable marker gene nptII.

INTRODUCTION: Animals with intentional genomic alterations (IGAs) hold promise for meeting increasing worldwide demand for animal-source proteins. As part of regulatory risk assessment for introducing animals with IGAs into the food chain, monitoring commensal bacterial microbiota is recommended due to concern that antimicrobial resistance genes used during IGA selection could be transferred, via horizontal gene transfer, to gastrointestinal or environmental bacterial populations, potentially contributing to antimicrobial resistance. The objective of this study was to assess the antimicrobial susceptibility patterns in commensal bacteria isolated from fecal samples of GalSafe™ pigs that have an IGA that includes the aminoglycoside resistance gene nptII. METHODS: Antimicrobial resistance rates observed in Escherichia coli, Salmonella, Campylobacter and Enterococcus isolated from GalSafe™ pigs were compared to resistance rates observed in conventional pigs at slaughter. Bacterial isolates were tested for antimicrobial resistance genes by PCR and one isolate underwent whole genome sequencing. RESULTS: In total, 137 bacterial isolates recovered from 55 fecal samples collected from 47 individual adult GalSafe™ pigs were evaluated. Prevalence of antimicrobial resistance in GalSafe™ pigs was generally similar to, or lower than, resistance prevalence reported from conventional pigs at slaughter, based on National Antimicrobial Resistance Monitoring System (NARMS) data. Higher resistance rates in GalSafe™ pigs were observed only for quinolones in Campylobacter coli (ciprofloxacin and nalidixic acid) and nitrofurantoin in Enterococcus spp. One isolate (E. coli) was positive for nptII neomycin resistance gene, the same gene used for IGA selection in GalSafe™ pigs, and the remaining 136 isolates were negative for nptII. However, the positive isolate did not appear to contain nptII derived from the GalSafe™ pig genome as the sequences flanking the gene did not match the IGA. DISCUSSION: We did not detect evidence of nptII gene transformation into bacterial species of potential human health importance in this population of GalSafe™ pigs.

NARMS↗

PubMed2026

Patterns of antimicrobial resistance genes in pathogens across One Health sectors in Ireland: an in silico approach.

As part of a rapid risk assessment, an in silico approach was used to detect antimicrobial resistance (AMR) in pathogenic isolates from humans, animals, and the environment. A total of 11,670 genomic data sets were retrieved from the NCBI Pathogen Detection system for Ireland, which represented 47 pathogenic species, including Salmonella enterica, Escherichia coli/Shigella spp., Staphylococcus aureus, Klebsiella pneumoniae, and Enterococcus faecium. Identifying the most critical pathogenic strains over time is essential, as these organisms significantly contribute to mortality, morbidity, and hospitalization. The analysis identified 799 antimicrobial resistance genes (ARGs), including their allelic diversity, 117 plasmid replicons, and 274 virulence factors. Several critical ARGs, particularly those conferring resistance to beta-lactams, aminoglycosides, quinolones, and colistin, were common across isolates originating from human, animal, and environmental sources, suggesting shared resistance profiles across One Health sectors. Klebsiella pneumoniae, E. coli/Shigella spp., S. enterica, and S. aureus were the dominant hosts of these ARGs and associated mobile genetic elements. Increasing resistance across major antibiotic classes aligned with trends reported across other European countries. This study provides a national-scale in silico comparison of AMR across pathogens and One Health sectors using publicly available genomic data. The findings help reinforce Ireland's AMR surveillance by showing which resistance genes are present and how they spread across critical pathogens in humans, animals, and the environment. These findings highlight the urgent need for improved antibiotic stewardship and integrated One Health surveillance to limit the emergence and spread of AMR.IMPORTANCEAntimicrobial resistance (AMR) is a growing threat to human, animal, and environmental health. This study used publicly available genomic data to identify antimicrobial resistance genes (ARGs) in key bacterial pathogens circulating in Ireland. By analyzing over 11,000 genomes from humans, animals, and the environment, we found that several dangerous resistance genes, including those against last-resort antibiotics, were widespread across different sources. The study highlights which bacteria and resistance genes are most critical and how they may spread between humans, animals, and the environment. These insights provide a national snapshot of AMR, supporting more effective monitoring and prevention strategies. By revealing patterns of resistance and modes of transmission, our findings underscore the importance of coordinated antibiotic stewardship and One Health approaches to slow the emergence and spread of resistant infections, protecting public health and ensuring antibiotics remain effective.

Humans↗

PubMed2026

Convergent evolution of immune evasion in ESKAPE pathogens: A cross-pathogen architecture of conserved host-defense checkpoints.

Antimicrobial resistance in ESKAPE pathogens is primarily attributed to resistance genes, yet persistent infections despite appropriate therapy implicate immune evasion as an independent driver of treatment failure. Although immune-evasion mechanisms have been extensively characterized in individual pathogens, their shared architecture across the ESKAPE group remains insufficiently integrated. This review synthesizes current evidence to show that phylogenetically diverse ESKAPE pathogens have convergently evolved conserved strategies to evade host immunity under comparable selective pressures. A cross-pathogen immune-evasion framework emerges, encompassing impaired pathogen recognition, complement inhibition, phagocyte dysfunction, immunometabolic reprogramming, biofilm-mediated protection, and persistence-promoting inflammation, together with pathogen-specific virulence mechanisms. These processes intersect with adaptive immune dysfunction and emerging concepts, including quorum-sensing-mediated immunomodulation, trained immunity, and the itaconate-succinate immunometabolic axis, forming an interconnected persistence network rather than isolated virulence traits. This systems-level perspective identifies conserved host-directed therapeutic targets that may complement conventional antimicrobial therapy across species. However, host-directed therapies, immunotherapeutics, and vaccines remain largely preclinical or have shown inconsistent clinical efficacy. Mechanistic evidence is strongest for Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae, whereas substantial knowledge gaps persist for Enterococcus faecium, Acinetobacter baumannii, and Enterobacter spp. Overcoming persistent ESKAPE infections will require targeting conserved host-pathogen interactions alongside pathogen-specific antimicrobial resistance mechanisms.

Convergent immune evasion↗

PubMed1979

Cefoxitin: single-agent treatment of mixed aerobic-anaerobic pelvic infections.

Cefoxitin (mefoxin), a new semisynthetic cephamycin antibiotic, resistant to degradation by beta-lactamase enzymes produced by bacteria. In vitro, cefoxitin is active against virtually all clinically important gram-negative facultative bacteria other than Pseudomonas and Enterobacter spp., gram-positive aerobic bacteria other than the enterococcus, and clinically important anaerobic organisms, including Bacteroides fragilis. This broad antibacterial spectrum suggested that cefoxitin might be an effective single antibiotic agent for the treatment of mixed aerobic-anaerobic infections in obstetric and gynecologic patients. In this investigation, the efficacy and safety of cefoxitin was evaluated in 109 patients--68 with salpingitis, 25 with endomyometritis, 9 with pelvic cellulitis, and 7 with pelvic abscesses. An average of 2.5 bacteria were isolated from each patient. Aerobic bacteria alone was isolated in 38% of patients, anaerobic bacteria alone in 25%, and a combination of aerobic and anaerobic bacteria was isolated in 37% of patients. Overall, 100 of 109 (92%) infections responded to treatment with cefoxitin alone. The major cause of treatment failure was the presence of abscesses requiring surgical drainage. In addition to being an effective single agent for the management of pelvic infections, cefoxitin proved to be safe and well tolerated by patients.

Abscess↗

PubMed2026

Systematic review on genomic insights into antimicrobial resistance in ESKAPE pathogens.

BACKGROUND: Antimicrobial resistance (AMR) is a major global public health threat. ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) pose a major threat owing to resistance to last-line antibiotics. Genomic surveillance is crucial to understanding global and regional antimicrobial resistance genes (ARGs) in AMR transmission. AIM: This systematic review synthesised global genomic evidence to identify global and region-specific ARGs distribution among ESKAPE pathogens. METHODS: Following PRISMA guidelines, studies published January 2019 to December 2024 were identified from PubMed, Google Scholar, and Web of Science. Eligible studies reported genomic characteristics and resistance patterns of one or more ESKAPE pathogens from any source. RESULTS: Seventy-seven studies were included, with most originating from Asia, followed by Europe and Africa. Clinical isolates predominated K. pneumoniae was the most frequently investigated pathogen, followed by S. aureus, P. aeruginosa, and A. baumannii. The most reported resistance genes were blaCTX-M, blaNDM, and blaSHV. Distinct regional patterns of antimicrobial resistance gene (ARG) distribution were observed, with tetracycline and quinolone resistance genes prevailing in Africa and South America, and blaOXA variants dominating in Asia and Europe. Region-specific ARG patterns were identified through descriptive synthesis and comparative analysis of study-reported frequencies. CONCLUSION: This review provides a synthesised global map of ARG distribution in ESKAPE pathogens, highlighting surveillance gaps in underrepresented regions and non-clinical settings. Addressing these gaps will support targeted genomic surveillance and stewardship programmes. WHAT THIS STUDY ADDS: This study contributes to the body of knowledge by mapping global and regional antimicrobial resistance gene patterns in ESKAPE pathogens, identifying key surveillance gaps and informing targeted AMR monitoring and stewardship strategies.

ESKAPE pathogens↗

PubMed1979

Studies with cefuroxime: a new beta-lactamase resistant cephalosporin.

28 patients suffering from a variety of bacterial infections have been treated with cefuroxime. 18 were cured and 6 improved during treatment. Side effects were minimal and intramuscular injection was well tolerated. Serum and urine levels well in excess of the MICs of sensitive organisms were obtained using dosages of 750 mg 8 hourly. Biliary excretion was impaired in the presence of obstruction, but adequate bile levels of cefuroxime were observed following relief of the obstruction. Cefuroxime was widely active against gram-negative bacilli and against Streptococcus faecalis, but less active against Bacteroides spp.

Adult↗

PubMed1975

Relationship of bacterial infection in urine and calculi to canine urolithiasis.

In 26 dogs treated surgically for urolithiasis, bacteriological examination of the urine and the interior of calculi showed that infection was present in both materials in 14 cases. Infection with phosphate calculi, present in 13 of these 14 dogs, was associated with a variety of bacteria including Staphylococcus aureus, Staph epidermidis, Streptococcus faecalis, Escherichia coli and Proteus spp. In a follow-up examination of 16 dogs, organisms different from the original isolates were recovered from some cases. The significance of the persistence of viable bacteria within canine bladder calculi is discussed.

Animals↗

PubMed1978

Association between Streptococcus faecalis urinary infections and graft rejection in kidney transplantation.

In the first month after transplantation 50% of 193 consecutive renal transplant recipients had bacteriuria. The most common organisms isolated were Streptococcus faecalis (34), Escherichia coli (28), Pseudomonas spp. (11), and staphylococcus (9). There was a significant correlation between infection with Str. faecalis and graft failure at one, three, and twelve months. This observation suggests that urinary infection with Str. faecalis may be associated with graft failure which is probably the result of immunological factors.

Adult↗

PubMed1979

Microbial impact of Canada geese (Branta canadensis) and whistling swans (Cygnus columbianus columbianus) on aquatic ecosystems.

Quantitative and qualitative analyses of the intestinal bacterial flora of Canada geese and whistling swans were carried out with the finding that wild birds harbor significantly more fecal coliforms than fecal streptococci. The reverse was typical of captive and fasting birds. Neither Salmonella spp. nor Shigella spp. were isolated from 44 migratory waterfowl that were wintering in the Chesapeake Bay region. Enteropathogenic Escherichia coli were detected in seven birds. Geese eliminated 10(7) and swans 10(9) fecal coliforms per day. Results of in situ studies showed that large flocks of waterfowl can cause elevated fecal coliform densities in the water column. From the data obtained in this study, it is possible to predict the microbial impact of migratory waterfowl upon aquatic roosting sites.

Animals↗

PubMed1978

Iron requirement and chelator production of staphylococci, Streptococcus faecalis and enterobacteriaceae.

The effect of iron deprivation on growth of 101 aerobic strains of gram-positive and gram-negative bacteria was studied on agar media in the presence of various concentrations of the synthetic iron chelator ethylene diamine diorthohydroxyphenyl acetic acid (EDDA) and the iron binding protein transferrin. Growth of Staphylococcus epidermidis was inhibited by 15 mM EDDA and 1.5 mM transferrin. Staphylococcus aureus was only inhibited by 44 mM EDDA and not by transferrin. None of the strains of S. faecalis was inhibited. The majority of the enterobacteriaceae (E. coli, Salmonella spp, Klebsiella spp) was inhibited by 44 mM EDDA and 1.5 mM transferrin. The relation between susceptibility and concentration of EDDA and transferrin was expressed as S-value for each species. Iron supply with various iron compounds could restore the effects of inhibition. In all species except in S. faecalis iron chelator production could be demonstrated, using indicator plates of media containing EDDA and flooded with 10(4)--10(5) colony forming units of indicator organisms. The iron chelator of both S. epidermidis and S. aureus could stimulate growth of S. epidermidis, but not that of enterobacteriaceae. Iron chelators from all gram-negative bacteria were functionally interchangeable, but did not stimulate growth of gram-positive bacteria.

Chelating Agents↗