Bacterial Infections Research Articles

Intravenous Versus Oral Omadacycline or Linezolid for Acute Bacterial Skin and Skin Infections: A post hoc Analysis of the OASIS Trials.

Appropriate oral antibiotic therapy for the treatment of acute bacterial skin and skin structure infections (ABSSSI) is a challenge, as current oral treatment guidelines do not fully cover the most common skin pathogens. Both linezolid and omadacycline are available as intravenous or bioequivalent oral formulations. This post hoc analysis of the OASIS-1 (ClinicalTrials.gov identifier NCT02378480) and OASIS-2 (ClinicalTrials.gov identifier NCT02877927) phase 3 trials assessed safety and clinical efficacy of intravenous (IV)-start versus oral (PO)-start therapy in patients treated with omadacycline or linezolid for ABSSSI. In OASIS-1, patients were randomized to IV omadacycline or linezolid, with optional switch to oral therapy, while patients in OASIS-2 received oral omadacycline or linezolid. Treatment was provided for 7-14days in both studies. The primary endpoint was an early clinical response (ECR) at 48 to 72h, defined as survival and ≥ 20% reduction in lesion size, without rescue antibacterial therapy. A total of 645 IV-start inpatients and 735 PO-start outpatients were assessed. Median age was 47years for the IV-start group and 44years for the PO-start group. Most patients had solely gram-positive infections (97% in each group; ECR [85.2% IV-start and 85.0% PO-start]), and the incidence of treatment-emergent adverse events (AEs) was similar between the groups. The most frequent AEs observed were nausea (11.2% [IV-start] versus 18.9% [PO-start]) and subcutaneous abscess (5.6% [IV-start] versus 1.9% [PO-start]). Discontinuation due to AEs was infrequent in both groups (2% [IV-start] versus 1.2% [PO-start]). Oral therapy is equally efficacious to IV therapy when omadacycline or linezolid is used to treat ABSSSIs. These data strengthen the evidence for oral omadacycline as a therapeutic option for ABSSSI, particularly for patients who have experienced treatment failure because of the limitations of other therapies. Clinicaltrials.gov, NCT02378480 and NCT02877927.

An integrative network-based approach to identify driving gene communities in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is an etiologically complex disease characterized by acute exacerbations and stable phases. We aimed to identify biological functions modulated in specific COPD conditions, using whole blood samples collected in the AERIS clinical study (NCT01360398). Considered conditions were exacerbation onset, severity of airway obstruction, and presence of respiratory pathogens in sputum samples. With an integrative multi-network gene community detection (MNGCD) approach, we analyzed expression profiles to identify communities of correlated genes. The approach combined different layers of gene interactions for each explored condition/subset of samples: gene expression similarity, protein-protein interactions, transcription factors, and microRNAs validated regulons. Heme metabolism, interferon-alpha, and interferon-gamma pathways were modulated in patients at both exacerbation and stable-state visits, but with the involvement of distinct sets of genes. An important gene community was enriched with G2M checkpoint, E2F targets, and mitotic spindle pathways during exacerbation. Targets of TAL1 regulator and hsa−let−7b − 5p microRNA were modulated with increasing severity of airway obstruction. Bacterial infections with Moraxella catarrhalis and, particularly, Haemophilus influenzae triggered a specific cellular and inflammatory response in acute exacerbations, indicating an active reaction of the host to infections. In conclusion, COPD is a complex multifactorial disease that requires in-depth investigations of its causes and features during its evolution and whole blood transcriptome profiling can contribute to capturing some relevant regulatory mechanisms associated with this disease. In this work, we explored multi-network modeling that integrated diverse layers of regulatory gene networks and enhanced our comprehension of the biological functions implicated in the COPD pathogenesis.

Mimicking Urinary Tract Infections Caused by Uropathogenic Escherichia coli Using a Human Three-Dimensional Tissue Engineering Model

Uropathogenic Escherichia coli are the main causal agent of urinary tract infections. These diseases can affect more than half of women during their lifetime. Moreover, recurrent urinary tract infections can affect up to 30% of patients, leading to higher social and economic costs for the community. No efficient treatment against the recurrent form of the disease has been discovered. Due to the low average rate of successful translation from 2D cell culture and in vivo animal models into clinical trials, new models that mimic pathologies, such as those produced by tissue engineering, are needed. A model of human-derived 3D bladder mucosa was produced by tissue engineering techniques using collagen gels and organ-specific primary human stromal and epithelial cell populations. This model was used to mimic the different steps of a urinary tract infection: adhesion, invasion, intracellular bacterial community and quiescent intracellular reservoir formation and, finally, bacteria resurgence after umbrella cell exfoliation through chitosan exposure to mimic the recurrent infection. The uropathogenic strain UTI-89-GFP was used as infectious bacteria and BL-21-GFP strain as a control. Our model is unique and is the first step toward mimicking the different phases of a UTI in a human context.

Infection-Associated Flares in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is characterised by generalised immune dysfunction, including infection susceptibility. Infection-associated flares (IAFs) are common and might rapidly self-resolve, paralleling infection resolution, but their specific clinical phenotype is poorly understood. Therefore, we screened 2039 consecutive visits and identified 134 flares, defined as a loss of the lupus low disease activity state (LLDAS), from 1089 visits at risk spanning over multiple follow-up years, yielding an average yearly LLDAS deterioration rate of 17%. Thirty-eight IAFs were isolated from the total flares and were mostly related to bacterial and herpesvirus infections. When compared to other flares (OFs; n = 98), IAFs showed no milder patterns of organ involvement and similar rates of long-term damage accrual, as estimated by conventional clinimetrics. Arthritis in IAFs was more severe than that in OFs [median (interquartile range) DAS-28 2.6 (2.3–4.1) vs. 2.0 (1.6–2.7); p = 0.02]. Viral IAFs were characterised by atypically lower levels of anti-DNA antibodies (p < 0.001) and possibly abnormally high complement levels when compared to flares of different origin. These data suggest that IAFs are of comparable or even higher severity than OFs and may subtend distinct pathophysiological mechanisms that are poorly tackled by current treatments. Further research is needed to confirm these data.

Epidural Catheter Bacterial Colonization and Infection in a Secondary Portuguese Hospital Setting

Epidural Catheter Bacterial Colonization and Infection in a Secondary Portuguese Hospital Setting

Feasibility of mNGS in joint replacement patients exhibiting elevated ESR and CRP levels without an underlying diagnosis

ObjectiveThe aim of this study is to investigate the viability of performing initial artificial joint replacement surgery in patients presenting with unexplained elevations in erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels.MethodsA cohort of 22 patients, comprising 11 cases each for knee and hip joint replacements, who underwent initial artificial joint replacement surgery between November 2020 and January 2022, was recruited. All patients exhibited elevated levels of ESR and CRP prior to surgery, the etiology of which remained undetermined. Intraoperatively, joint effusion and periarticular tissues were preserved for subsequent bacterial culture and metagenomic next-generation sequencing (mNGS). Postoperatively, a combination of intravenous and local antibiotics was administered for anti-infective management. In cases where bacterial culture and/or mNGS yielded positive results, patients were diagnosed with periprosthetic joint infections (PJI) and underwent one-stage revision; conversely, negative findings led to the discontinuation of intravenous and local antibiotics therapy.ResultsAmong the cohort of 22 patients, bacterial cultures yielded negative results, while mNGS identified bacterial infection in 14 patients (63.63%), viral infection in 1 patient (4.55%), and yielded negative results in 7 patients (31.82%). All surgical incisions achieved per primam. Subsequent follow-up assessments conducted for more than 1 year postoperatively revealed absence of PJI among the patients, all of whom exhibited satisfactory progress in their rehabilitation exercises. Notably, the Knee Society Score (KSS) for knee joint patients significantly improved from a preoperative mean of 48.7 ± 3.3 points to 84.3 ± 2.2 points postoperatively, whereas the Harris Hip Score for hip joint patients increased significantly from preoperative mean of 50.6 ± 3.6 points to 87.1 ± 1.6 points (P < 0.01).ConclusionIn cases where patients present with unexplained elevations in ESR and CRP levels, primary artificial joint replacement can be undertaken following a one-stage revision approach for PJI.

MOF-Enhanced Phototherapeutic Wound Dressings Against Drug-Resistant Bacteria.

Phototherapy is a low-risk alternative to traditional antibiotics against drug-resistant bacterial infections. However, optimizing phototherapy agents, refining treatment conditions, and addressing misuse of agents, remain a formidable challenge. This study introduces a novel concept leveraging the unique customizability of metal-organic frameworks (MOFs) to house size-matched dye molecules in "single rooms". The mesoporous iron(III) carboxylate nanoMOF, MIL-100(Fe), and the hydrophobic heptamethine cyanine photothermal dye (Cy7), IR775, are selected as model systems. Their combination is predicted to minimize dye-dye interactions, leading to exceptional photostability and efficient light-to-heat conversion. Furthermore, MIL-100(Fe) preserves the antimicrobial nature of hydrophobic IR775, enabling it to disrupt bacterial cell envelopes. Through electrospinning, MIL-100(Fe)@IR775 nanoparticles are shaped into a gelatin-based film dressing for the treatment of skin wounds infected by Methicillin-resistant Staphylococcus aureus (MRSA). Activation of the dressing requires only a portable near-infrared light-emitting diode (NIR LED) and induces both low-dose photodynamic therapy (LPDT) and mild-temperature photothermal therapy (MPTT). Combined with the antimicrobial properties of IR775 and ferroptosis-like lipid peroxidation induced by MIL-100(Fe), the photoactive dressing eradicates MRSA and the healing is as quick as the uninfected wounds. This safe, cost-effective, and multifunctional therapeutic wound dressing offers a promising solution to overcome the current bottleneck in phototherapy.

Pathogen-specific social immunity is associated with erosion of individual immune function in an ant

Contagious diseases are a major threat to societies in which individuals live in close contact. Social insects have evolved collective defense behaviors, such as social care or isolation of infected workers, that prevent outbreaks of pathogens. It has thus been suggested that individual immunity is reduced in species with such ‘social immunity’. However, this hypothesis has not been tested functionally. Here, we characterize the immune response of the ant Lasius niger using a combination of genomic analysis, experimental infections, gene expression quantification, behavioural observations and pathogen quantifications. We uncover a striking specialization of immune responses towards different pathogens. Systemic individual immunity is effective against opportunistic bacterial infections, which are not covered by social immunity, but is not elicited upon fungal infections, which are effectively controlled by social immunity. This specialization suggests that immune layers have evolved complementary functions predicted to ensure the most cost-effective response against a wide range of pathogens.

A Single-Center Retrospective Study of Bacterial Infections After Acute Ischemic Stroke: The Prevalence Before and During the COVID-19 Pandemic

Background and Objectives: The management of ischemic stroke involves care that is integrated and comprehensive, including the prevention of infection complications. This study aimed to investigate the prevalence and profile of bacterial infections after acute ischemic stroke both before and during the coronavirus disease 2019 (COVID-19) pandemic. Materials and Methods: A retrospective cross-sectional study examined the medical records of hospitalized acute ischemic stroke patients who had microbiological cultures taken at the National Brain Center Hospital Prof. Dr. dr. Mahar Mardjono, Jakarta, Indonesia, from 1 January 2018 to 31 December 2021. The percentage of positive bacterial growth in the microbiological cultures was used to determine the prevalence of bacterial infection after acute ischemic stroke. Results: A total of 519 patients met the study criteria, including 48 and 471 patients with infections before and during the COVID-19 pandemic. The prevalence of bacterial infection after acute ischemic stroke was 17.9%. There were significant differences in the prevalence of bacterial infection after acute ischemic stroke before and during the COVID-19 pandemic (87.5% vs. 10.8%). Staphylococcus sp. and Klebsiella sp. were the most frequently observed. The risk factors that influenced bacterial infection after acute ischemic stroke were intensive care stay (OR 0.22; 95%CI 0.13–0.39, p-value &lt; 0.001), sepsis (OR 1.99; 95%CI 1.12–3.53, p-value = 0.019), COVID-19 infection (OR 4.81; 95%CI 2.64–8.76, p-value &lt; 0.001), the use of steroids (OR 0.31; 95%CI 0.14–0.67, p-value = 0.003), and the use of TPN (OR 0.34; 95%CI 0.13–0.86, p-value = 0.022). Conclusions: Following the start of the COVID-19 pandemic, there was a decrease in the prevalence of bacterial infections after AIS. Patients with bacterial infections had different profiles before and during the COVID-19 pandemic.

Effect of Surface-Immobilized States of Antimicrobial Peptides on Their Ability to Disrupt Bacterial Cell Membrane Structure

Antimicrobial peptide (AMP) surfaces are widely used to inhibit biofilm formation and bacterial infection. However, endpoint-immobilized AMPs on surfaces are totally different from free-state AMPs due to the constraints of the surface. In this work, the interactions between AMPs and bacterial cell membranes were analyzed through coarse-grained molecular dynamics and all-atom molecular dynamics simulations. This AMP disrupted membrane structure by altering the thickness and curvature of the membrane. Furthermore, the effect of surface-immobilized states of AMPs on their ability to disrupt membrane structure was revealed. The immobilized AMPs in the freeze-N system could bind to the membrane and disrupt the membrane structure through electrostatic forces between positively charged N-terminal amino acid residues and the negatively charged membrane, while the immobilized AMPs in the freeze-C system were repelled. The results will aid in the rational design of new AMP surfaces with enhanced efficacy and stability.

Selenicereus undatus (Dragon Fruit) Phytochemicals for Managing Three Human Pathogenic Bacteria: An In Vitro and In Silico Approach

Objectives: Antibiotic-resistant bacterial infections are a growing global concern. A natural remedy for bacterial infections could be available in the Selenicereus undatus fruit, but its antibacterial and biochemical properties are not fully known. Methods: In this study, the biochemical composition and antibacterial, antioxidant, and cytotoxic activities of the Jindu No. 1 (JD) and Bird’s Nest (YW) dragon fruit varieties and their potential effects against E. coli, Pseudomonas sp., and Staphylococcus sp. were scrutinized. Results: The JD fruit extract showed higher antibacterial activity than the YW variety against E. coli, Pseudomonas sp., and Staphylococcus sp. in vitro. Additionally, the JD variety demonstrated more significant antioxidant activity than the YW variety and showed less cytotoxic activity. The JD variety had a higher glucose content, while the YW variety had a higher fructose content, and the phytoconstituents analysis confirmed 659 metabolites in total from the two varieties. Through in silico analyses, phytoconstituents were evaluated to identify potential drug molecules against the selected bacterial strain. Moreover, the molecular docking study revealed that riboprobe and Z-Gly-Pro might be effective against E. coli, 4-hydroxy retinoic acid, and that succinyl adenosine may target Pseudomonas sp., and xanthosine and 2′-deoxyinosine-5′-monophosphate may be effective against Staphylococcus sp. These results were further validated by 100 ns Molecular Dynamics (MD) simulation, and all of the selected compounds exhibited acceptable ADMET features. Conclusions: Therefore, phytoconstituents from S. undatus fruit varieties could be employed to fight human bacterial diseases, and future studies will support the continuation of other biological activities in medical research.

Staphylococcus felis C4 exhibits invitro antimicrobial activity against methicillin-resistant Staphylococcus pseudintermedius in a novel canine skin explant model.

Canine superficial pyoderma is a common bacterial skin infection of dogs, generally caused by Staphylococcus pseudintermedius. The C4 strain of Staphylococcus felis was recently discovered to have strong antimicrobial activity against S. pseudintermedius in mice. We aimed to evaluate invitro if this antimicrobial activity was maintained using a novel canine skin explant model. Punch biopsies (8 mm) of skin from recently euthanised dogs were collected and placed into six-well plates on top of an agarose pedestal. Histological examination of the skin explants showed an intact dermal-epidermal organisation and a stratum corneum that was successfully colonised by S. pseudintermedius after topical application. The number of colony forming units of S. pseudintermedius showed a 2 log increase after 24 h colonisation, indicating that the explant supported bacterial growth. By contrast, co-treatment with S. felis C4 live bacteria and its sterile protein product significantly reduced the growth of a methicillin-susceptible (ST540, p = 0.0357) and a methicillin-resistant (MR) strain (ST71, p = 0.0143) of S. pseudintermedius. No detectable bacteria were recovered from or visualised on skin 24 h posttreatment with the S. felis C4 sterile protein product. Using a novel canine explant model, we demonstrate that the S. felis C4 strain inhibits the growth of S. pseudintermedius and that it is a promising candidate for a new probiotic therapy to treat cutaneous infections caused by S. pseudintermedius, including MR strains.

The protective effect and immunomodulatory ability of orally administrated Lacticaseibacillus rhamnosus GG against Mycoplasma pneumoniae infection in BALB/c mice.

Mycoplasma pneumoniae represents one of the significant etiologies of community-acquired pneumonia in pediatric patients. However, clinical treatment of M. pneumoniae infection in children has encountered challenges due to the escalating resistance to quinolones. Numerous studies have highlighted the potential of probiotic lactobacillus administration in boosting immune responses to bacterial and viral respiratory infections. In this study, the protective efficacy of pre-oral administration of Lacticaseibacillus rhamnosus GG (LGG), Limosilactobacillus reuteri F275, Lactiplantibacillus plantarum NCIMB 8826, L. plantarum S1 or L. plantarum S2 was evaluated in the BALB/c mice model; it was observed that among these five strains of lactobacillus, the supplementation of LGG exhibited the most significant protective effect against M. pneumoniae infection. Moreover, when administered orally, both live LGG and heat-inactivated LGG have demonstrated efficacy in reducing the burden of M. pneumoniae in the lungs and alleviating pulmonary inflammation. Oral supplementation with LGG resulted in the inhibition of neutrophil recruitment into the lungs and increased recruitment of alveolar macrophages in M. pneumoniae-infected mice. Additionally, LGG supplementation led to increased production of IL-10 and secretory IgA (sIgA), while suppressing the levels of IL-1β, IL-6, IL-17A, and TNF-α in the lungs of mice infected with M. pneumoniae. The data suggests that supplementation with LGG can modulate immune responses, decrease pathogen load, and alleviate inflammatory injury in the lungs of M. pneumoniae-infected mice.

Consumer acceptance of bacteriophage technology for microbial control

As global concerns and awareness of the threat posed by antimicrobial resistance (AMR) grow, the One Health initiative provides a framework to advance public understanding of and willingness to address AMR. The use of bacteriophages as a non-antibiotic means to control bacterial infections aligns with this framework, but it is unknown whether the use of new antibiotic alternatives, and bacteriophages in particular, will find acceptance among consumers. Within the context of poultry production and consumption, we sampled 1497 Pakistani consumers studying their knowledge of and familiarity with antibiotics, bacteriophages and AMR, whether they perceived AMR as a threat, and their willingness to accept alternative microbial control technologies. Additionally, we tested the impact information about bacteriophages had on the different concepts as well as respondents’ perception of different chicken quality attributes. Using both Probit and Multivariate Probit models we found that familiarity with antibiotics and bacteriophages is significantly associated with the acceptance of alternative microbial control technologies and perceptions of resulting products. Moreover, we find that providing information about the technology does not significantly alter respondent’s perception of most quality attributes.

Scabies: a clinical update.

Scabies is the most common neglected tropical disease with cutaneous manifestations, disproportionately affecting socially disadvantaged populations living in overcrowded settings. Scabies infestation is characterised by a generalised intractable pruritus, and is often complicated by secondary bacterial infection, which can lead to a range of complications. Scabies is a clinical diagnosis and requires an adequate degree of suspicion. The use of dermoscopy may improve diagnostic accuracy. In Australia, the first-line treatment recommended for scabies is topical permethrin 5% cream, applied to the whole body and repeated in one week. Oral ivermectin is subsidised by the Pharmaceutical Benefits Scheme with streamlined authority for patients who have completed and failed treatment with topical therapy, have a contraindication to topical treatment or have crusted scabies. Early identification and prompt initiation of treatment is key to minimise the disease burden of scabies.

Living without pain: A 10-year study of congenital insensitivity to pain with anhidrosis.

Congenital Insensitivity to Pain with Anhidrosis (CIPA) is a rare hereditary neuropathy caused by NTRK1 gene mutations, predisposing patients to recurrent infections and chronic wounds. Long-term studies on microbial and clinical outcomes in CIPA are limited. This study presents analysis of infection patterns, antibiotic resistance, and clinical outcomes in CIPA patients. A comprehensive ten-year retrospective cohort study was conducted at Soroka University Medical Center, Beer Sheva, Israel, from January 2014 to January 2023. Electronic medical records were reviewed to identify 63 CIPA patients, all were of consanguineous Bedouin families. Data collection included demographic details, clinical presentations, genetic analysis, documentation of infections, wound sites, hospital duration, and surgical interventions. Staphylococcus aureus, notably methicillin-resistant, dominated, with Gram-negative bacteria common in lower limbs. The study noted reduced extended-spectrum beta-lactamase bacteria and linked demographic factors to infection traits, antibiotic resistance, and surgical needs. This study provides valuable insights into the clinical and microbial patterns of CIPA, highlighting dynamic shifts in microbial compositions and antibiotic resistance profiles over time. Staphylococcus aureus, and Gram-negative bacteria particularly in lower limb infections, pose significant challenges in patient management. The findings underscore the importance of tailored approaches to address evolving microbial profiles and optimize patient care in CIPA. Key Message: This is the largest cohort study on CIPA to date, highlighting the dominance of Staphylococcus aureus, including methicillin-resistant strains, and significant Gram-negative bacterial infections in lower limbs. Contribution to Literature: It draws parallels between infection dynamics in CIPA and diabetic foot ulcers, emphasizing similar challenges due to neuropathy and ischemia, enhancing understanding of infection susceptibility and management in neuropathic conditions. The findings inform clinical practices by detailing infection and resistance patterns, supporting the development of targeted treatment strategies to improve outcomes for CIPA and similar conditions.

Case Report: Osteosynthesis-associated infection with Ochrobactrum intermedium after acetabular fracture

Ochrobactrum intermedium (O. intermedium) is a gram-negative, non-fermenting bacterium closely related to Brucella genus. O. intermedium resembles an emergent human pathogen that has rarely been detected in both immunocompetent and immunodeficient patients. A musculoskeletal infection with O. intermedium has not been described in the literature. We present the first case of an osteosynthesis-associated infection (OAI) with O. intermedium in an 80-year-old female patient after osteosynthesis of an acetabular fracture. The patient was admitted to the emergency department 6 months after osteosynthesis of a posterior column acetabular fracture treated via open reduction and internal plate fixation of the posterior column. The patient demonstrated tenderness, redness and swelling at the insertion site as well as a fistula. The radiological controls showed femoral head necrosis and partial protrusion of the head into the pelvis. The laboratory parameters showed no pathological findings. OAI was assumed and a two-stage revision with implant removal and resection arthroplasty in the first stage and hip arthroplasty in the second stage was performed. All microbiological specimens taken at the osteosynthesis site and the hip joint grew O. intermedium. The pathogen was determined using the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) method. Antibiotic regime consisted of intravenous (IV) meropenem for two weeks followed by oral ciprofloxacin and cotrimoxazole. Implantation of the hip prosthesis was performed 6 weeks after the index surgery using a cementless revision cup and a cemented stem. Meropenem and vancomycin IV were given for one week followed by ciprofloxacin and doxycycline for another 5 weeks. 24 months after the surgery, the patient is infection free and satisfied with the result. With this case report we would like to increase awareness of possible implant-associated bacterial infections caused by O. intermedium.

Probiotic-Loaded Bacterial Cellulose as an Alternative to Combat Carbapenem-Resistant Bacterial Infections

Background: Carbapenems are one of the mainstays of treatment for antibiotic-resistant bacteria (ARB). This has made the rise of carbapenem-resistant bacteria a threat to global health. In fact, the World Health Organization (WHO) has identified carbapenem-resistant bacteria as critical pathogens, and the development of novel antibacterials capable of combating infections caused by these bacteria is a priority. Objective: With the aim of finding new alternatives to fight against ARB and especially against carbapenem-resistant bacteria, we have developed a series of living materials formed by incorporating the probiotics Lactobacillus plantarum (Lp), Lactobacillus fermentum (Lf), and a mixture of both (L. plantarum+L. fermentum) into bacterial cellulose (BC). Results: These probiotic-loaded bacterial celluloses inhibited the proliferation of three ARB, including two carbapenem-resistant enterobacteria (CRE), identified as Klebsiella pneumoniae and Enterobacter cloacae, and a carbapenem-resistant Pseudomonas aeruginosa. Interestingly, while the probiotics L. plantarum, L. fermentum, and the mixture of both were found to be inactive against these ARB, they became active once incorporated into BC. Conclusions: The increase in activity is due to the known effect that cells increase their activity once incorporated into a suitable matrix, forming a living material. For the same reasons, the probiotics in the living materials BC–L. plantarum, BC–L. fermentum, and BC–L. plantarum+L. fermentum showed increased stability, allowing them to be stored with bacterial activity for long periods of time (two months).

A Systematic Review of Aquatic Organism Antimicrobial Peptides

Antimicrobial peptides (AMPs), sourced from various organisms, including aquatic life, are promising alternatives to combat antibiotic resistance. Their investigation is essential amid global antibiotic resistance concerns. The invaluable impact of antibiotics on human health, having saved numerous lives, is currently at risk. The growing global incidence of antibiotic-resistant bacteria poses a serious challenge to their ability to effectively treat various illnesses. This situation demands immediate attention and the exploration of alternative medical solutions. One of the most promising alternatives to antibiotics is antimicrobial peptides (AMPs), which can treat bacterial infections, particularly those brought by multi-drug-resistant pathogens. With a particular focus on their antimicrobial properties, this systematic review aims to evaluate and classify recent AMPs isolated from aquatic organisms. This review advances knowledge of these aquatic life-derived AMPs’ potential as alternatives to conventional antibiotics by examining their unique antibacterial characteristics and modes of action. A systematic review of articles published in English between 2014 and 2024 was carried out in the Science Direct, PubMed NCBI and Google Scholar databases using keywords and inclusion and exclusion criteria. A total of 33 potential AMPs isolated from aquatic organisms had been reported, and 21 of the AMPs were reported to have functional antimicrobial activities. Continuous research and study of natural substances, particularly AMPs, remain critical in pursuing alternatives to conventional antibiotics for effective treatments in combating antibiotic resistance. Therefore, ongoing research holds significant importance in identifying and harnessing the potential of AMPs for future medical applications.

Isolation and Characterization of a Novel Jumbo Phage HPP-Temi Infecting Pseudomonas aeruginosa Pa9 and Increasing Host Sensitivity to Ciprofloxacin

Pseudomonas aeruginosa is a bacteria responsible for many hospital-acquired infections. Phages are promising alternatives for treating P. aeruginosa infections, which are often intrinsically resistant. The combination of phage and antibiotics in clearing bacterial infection holds promise due to increasing reports of enhanced effectiveness when both are used together. The aim of the study is to isolate and characterize a novel P. aeruginosa phage and determine its effectiveness in in vitro combination with antibiotics in controlling P. aeruginosa. In this study, a novel jumbo myophage HPP-Temi infecting P. aeruginosa Pa9 (PP334386) was isolated from household sewage. Electron micrographs of the phage were obtained to determine the morphological features of HPP-Temi virions. Complete genome analysis and a combination of Pseudomonas phage HPP-Temi with antibiotics were examined. The phage HPP-Temi was able to productively infect P. aeruginosa ATCC 9027 but was unable to infect a closely related genus. The phage was stable at 4–37 °C, 0.5% NaCl, and pH 8 for at least one hour. The HPP-Temi genome is a 302,719-bp-long dsDNA molecule with a GC content of 46.46%. The genome was predicted to have 436 ORFs and 7 tRNA genes. No virulence factor-related genes, antimicrobial resistance, or temperate lifestyle-associated genes were found in the phage HPP-Temi genome. Phage HPP-Temi is most closely related to the known or tentative representatives of the Pawinskivirus genus and can be proposed as a representative for the creation of a novel phage species in that genus. The phage and antibiotics (Ciprofloxacin) combination at varying phage titers (103, 106, 109) were used against P. aeruginosa Pa9 (PP334386) at 3.0 × 108 CFU/mL, which was carried out in triplicate. The result showed that combining antibiotics with phage significantly reduced the bacteria count at 103 and 106 titers, while no growth was observed at 109 PFU/mL. This suggests that the effect of phage HPP-Temi in combination with antibiotics is a potential and promising agent for the control of P. aeruginosa infections.