Gram-positive Anaerobes Research Articles

Impact of Dual-coated Silver Nanoparticle and Antibiotic Sutures on Wound Healing in Inflammatory Mouse Models

ABSTRACT Background: The use of silver nanoparticles (AgNPs) in biomedicine has emerged in a big way owing to its antibacterial and anti-inflammatory properties. We hypothesize that combining the AgNPs with antibiotics for coating sutures will enhance the antibacterial property of sutures with the added advantage of the immunomodulatory effect of AgNPs on tissue healing. Materials and Methods: Polyglactin sutures were coated with AgNPs using the dip-coating method. The uniform coating and morphology of AgNPs on the suture surface were confirmed using scanning electron microscopy (SEM). Each type of suture – polyglactin plain, antibiotic coated (Triclosan), AgNP coated, and dually coated (antibiotic and AgNP) – was assessed for their antibacterial properties against Gram-positive bacteria, Gram-negative bacteria, and anaerobes. These sutures were utilized in an abdominal and systemic inflammatory mice model for ileal anastomosis. The intestinal tissue was evaluated for acute and chronic inflammation and collagen deposition to assess the healing and inflammatory response. Results: The SEM and energy dispersive X-ray analysis showed successful coating of AgNPs on plain and antibiotic-coated sutures. In comparison with the other groups, the dually coated suture had the best in vitro antibacterial efficacy. The AgNP-coated sutures were able to decrease both acute and chronic inflammatory cell infiltration, but the collagen synthesis and deposition were enhanced. Conclusion: AgNPs can be coated on Polyglactin suture either alone or in combination with antibiotics with preserved antibacterial effects. The dual coating of sutures gives a synergistic antibacterial effect. The AgNP diminishes immune response in the presence of preserved extracellular matrix generation.

BWC0977, a broad-spectrum antibacterial clinical candidate to treat multidrug resistant infections

The global crisis of antimicrobial resistance (AMR) necessitates the development of broad-spectrum antibacterial drugs effective against multi-drug resistant (MDR) pathogens. BWC0977, a Novel Bacterial Topoisomerase Inhibitor (NBTI) selectively inhibits bacterial DNA replication via inhibition of DNA gyrase and topoisomerase IV. BWC0977 exhibited a minimum inhibitory concentration (MIC90) of 0.03–2 µg/mL against a global panel of MDR Gram-negative bacteria including Enterobacterales and non-fermenters, Gram-positive bacteria, anaerobes and biothreat pathogens. BWC0977 retains activity against isolates resistant to fluoroquinolones (FQs), carbapenems and colistin and demonstrates efficacy against multiple pathogens in two rodent species with significantly higher drug levels in the epithelial lining fluid of infected lungs. In healthy volunteers, single-ascending doses of BWC0977 administered intravenously (https://clinicaltrials.gov/study/NCT05088421) was found to be safe, well tolerated (primary endpoint) and achieved dose-proportional exposures (secondary endpoint) consistent with modelled data from preclinical studies. Here, we show that BWC0977 has the potential to treat a range of critical-care infections including MDR bacterial pneumonias.

Evaluating the Depth of Penetration of Calcium Hydroxide Mixed With Three Different Herbal Essential Oils Using a Confocal Laser Scanning Microscope.

Introduction The goal of endodontic therapy is to completely eliminate the infection and stop microbesfrom infecting or reinfecting the root canal and the periradicular tissues. Amongst the primary microorganisms,Enterococcus faecalis (E. faecalis), a Gram-positive anaerobe, is the main cause of pulpal and periapical inflammation causing root canal failure. Literature evidenceshows that the gold-standard calcium hydroxide is ineffective against E. faecalisdue to its resistance to the alkaline pH and proton pump mechanism. Herbal essential oils such as oregano, basil, and thyme are known to possess antimicrobial properties against E. faecalis. However, their combination with calcium hydroxide as an intracanal medicament and thedepth of penetration is still unknown. Aim To evaluate the depth of penetration of calcium hydroxide mixed with three different herbal essential oils using a confocal laser scanning microscope. Material and methods Fifty single-rooted premolars were decoronated and randomly divided into five groups. Group 1 - Oregano oil with calcium hydroxide, Group 2 - Basil oil with Calcium hydroxide, Group 3 - Thyme oil with calcium hydroxide, Group 4 - Calcium hydroxide with saline, Group 5 - Negative control. The teeth were instrumented and inoculated with E. faecalis and incubated for 21 days. Calcium hydroxide mixed with respective oils or saline and 0.1% rhodamine B dye was placed in the canals and again incubated for 7 days. Two sections each of 1 mm were horizontally cut at 3 mm and 5 mm from the apex and later subjected to a confocal laser scanning microscope to evaluate the depth of penetration. One-way ANOVA, post-hoc Tukey test, and student t-test were performed. Results At the middle third, basil oil had the maximum depth of penetration (1377.47±14.1 µm) followed by oregano oil (1345.4±26.5 µm) and thyme oil (1160.4±24.6 µm). At apical third, basil oil (1152.4±31.6 µm) showed maximum depth of penetration, followed by thyme (988.3±26.2 µm) andoregano oils (419.5±19.8 µm). The depth of penetration of these oils was greater at the middle third than at the apical third. Conclusion Basil, oregano, and thyme oilhave good penetration depth into the dentinal tubules and can be successfully used in root canal procedures as intracanal medicaments.

Botulinum toxin: a new differential diagnosis for a lytic bone lesion

BackgroundBotulinum toxin, produced by the Gram-positive anaerobe Clostridium botulinum, is composed of seven antigenic subtypes (A, B, C, D, E, F, and G). Currently, only Botulinum toxin type A, commonly referred to as “Botox,” is approved for clinical use, given its relatively safe clinical profile. Botulinum toxin type A has a wide range of therapeutic indications, including treatment for dystonia, migraine headache, neurogenic bladder, and large muscle spastic disorders. However, the toxin is most widely known for its cosmetic effects in treating wrinkles and facial lines.Case presentationThis article describes a 62-year-old Caucasian female who presented for investigation and workup of an isolated lytic lesion of her frontal bone a few weeks after administration of botulinum toxin injection into the corresponding site in the frontalis muscle. This presented as a large, palpable, painless forehead lump causing significant psychological distress. After no neoplastic cause for the lesion was found and histopathology was performed, our researchers concluded that the most likely explanation was that the bony lytic lesion resulted from inadvertent injection of the “Botox” neurotoxin through the intended target muscle and into the cortex of the underlying bone.ConclusionsOur search of the literature failed to identify any previous cases of this occurring. However, as the popularity of this cosmetic procedure only increases, we believe that this represents an important possible differential for isolated lytic lesion after administration of “Botox” injection.

Qualitative assessment of the removable denture microbiome.

Assessment of the denture plaque can provide a valuable report regarding the oral health of geriatric patients and the oral hygiene habits in this population group. Focusing on the current research gap on this topic in Romania, our research aims to highlight the microbial plaque on the different surfaces and types of removable poly(methyl methacrylate) (PMMA) prostheses to qualitatively evaluate the microbial species, and to assess the combined effect of mechanical and chemical cleaning of dentures on the prosthetic microbiome. The prosthetic plaque from four denture wearers was identified with a UV activated fluorescent revealer and digitally photographed. Swab samples according to a certain hygiene protocol were cultured on three different growth media such as blood agar (BA), bromothymol blue lactose agar (AABTL) and Sabouraud dextrose agar (SDA). Denture plaque was variably distributed on the surface of the prostheses. Regardless of the denture type (conventional complete denture, tooth or implant supported overdenture, removable partial denture) the microbial plaque was identified at the retentive areas, especially at interdental spaces. The main plaque deposition areas were the vestibular incline of the labial flange of the maxillary denture and the lingual incline of the posterior lingual flange of the mandibular denture. The prosthetic microbiome consisted of pathogenic Gram-positive aerobes (Streptococcus spp. and coagulase-negative Staphylococcus spp.), Gram-positive anaerobes (Actinomyces spp. and Klebsiella spp.) as well as subspecies of fungi of the genus Candida. Despite its poor variety, the denture microbiome in the investigated cases hosts colonies with high pathogenic potential. Some areas of the prostheses are more likely to accumulate dental plaque. Dentists should insist through more regular checks of the patients and their caregivers on ensuring the biocontrol of the dentures, especially in frail geriatric patients exposed to greater risks related to general health.

An Update on the Role and Potential Molecules in Relation to Ruminococcus gnavus in Inflammatory Bowel Disease, Obesity and Diabetes Mellitus.

Ruminococcus gnavus (R. gnavus) is a gram-positive anaerobe commonly resides in the human gut microbiota. The advent of metagenomics has linked R. gnavus with various diseases, including inflammatory bowel disease (IBD), obesity, and diabetes mellitus (DM), which has become a growing area of investigation. The initial focus of research primarily centered on assessing the abundance of R. gnavus and its potential association with disease presentation, taking into account variations in sample size, sequencing and analysis methods. However, recent investigations have shifted towards elucidating the underlying mechanistic pathways through which R. gnavus may contribute to disease manifestation. In this comprehensive review, we aim to provide an updated synthesis of the current literature on R. gnavus in the context of IBD, obesity, and DM. We critically analyze relevant studies and summarize the potential molecular mediators implicated in the association between R. gnavus and these diseases. Across numerous studies, various molecules such as methylation-controlled J (MCJ), glucopolysaccharides, ursodeoxycholic acid (UDCA), interleukin(IL)-10, IL-17, and capric acid have been proposed as potential contributors to the link between R. gnavus and IBD. Similarly, in the realm of obesity, molecules such as hydrogen peroxide, butyrate, and UDCA have been suggested as potential mediators, while glycine ursodeoxycholic acid (GUDCA) has been implicated in the connection between R. gnavus and DM. Furthermore, it is imperative to emphasize the necessity for additional studies to evaluate the potential efficacy of targeting pathways associated with R. gnavus as a viable strategy for managing these diseases. These findings have significantly expanded our understanding of the functional role of R. gnavus in the context of IBD, obesity, and DM. This review aims to offer updated insights into the role and potential mechanisms of R. gnavus, as well as potential strategies for the treatment of these diseases.

Oral Clostridium butyricum on mice endometritis through uterine microbiome and metabolic alternations.

Endometritis occurs frequently in humans and animals, which can negatively affect fertility and cause preterm parturition syndrome. Orally administered Clostridium butyricum, a butyrate-producing gram-positive anaerobe, exhibits anti-inflammatory effects. However, the precise mechanism by which Clostridium butyricum attenuates endometritis remains unclear. This in vivo study evaluated the anti-inflammatory effects of orally administered Clostridium butyricum on uterine tissues. In addition, we conducted uterine microbiome and lipid metabolome analyses to determine the underlying mechanisms. Female Balb/c mice were divided into the following four groups (n = 5-20): (1) mock group, (2) only operation group (mice only underwent operation to exposed uterine horns from the side), (3) control group (mice underwent the same operation with the operation group + perfusion of lipopolysaccharide solution from uterine horns), and (4) Clostridium butyricum administration group (mice underwent the same operation with the control group + oral Clostridium butyricum administration from days 0 to 9). Clostridium butyricum was administered via oral gavage. On day 10, we investigated protein expression, uterine microbiome, and lipid metabolism in uterine tissues. Consequently, orally administered Clostridium butyricum altered the uterine microbiome and induced proliferation of Lactobacillus and Limosilactobacillus species. The effects can contribute to show the anti-inflammatory effect through the interferon-β upregulation in uterine tissues. Additionally, oral Clostridium butyricum administration resulted in the upregulations of some lipid metabolites, such as ω-3 polyunsaturated fatty acid resolvin D5, in uterine tissues, and resolvin D5 showed anti-inflammatory effects. However, the orally administered Clostridium butyricum induced anti-inflammatory effect was attenuated with the deletion of G protein-coupled receptor 120 and 15-lipooxgenase inhibition. In conclusion, Clostridium butyricum in the gut has anti-inflammatory effects on uterine tissues through alterations in the uterine microbiome and lipid metabolism. This study revealed a gut-uterus axis mechanism and provided insights into the treatment and prophylaxis of endometritis.

Genetic disruption of the bacterial raiA motif noncoding RNA causes defects in sporulation and aggregation

Several structured noncoding RNAs in bacteria are essential contributors to fundamental cellular processes. Thus, discoveries of additional ncRNA classes provide opportunities to uncover and explore biochemical mechanisms relevant to other major and potentially ancient processes. A candidate structured ncRNA named the "raiA motif" has been found via bioinformatic analyses in over 2,500 bacterial species. The gene coding for the RNA typically resides between the raiA and comFC genes of many species of Bacillota and Actinomycetota. Structural probing of the raiA motif RNA from the Gram-positive anaerobe Clostridium acetobutylicum confirms key features of its sophisticated secondary structure model. Expression analysis of raiA motif RNA reveals that the RNA is constitutively produced but reaches peak abundance during the transition from exponential growth to stationary phase. The raiA motif RNA becomes the fourth most abundant RNA in C. acetobutylicum, excluding ribosomal RNAs and transfer RNAs. Genetic disruption of the raiA motif RNA causes cells to exhibit substantially decreased spore formation and diminished ability to aggregate. Restoration of normal cellular function in this knock-out strain is achieved by expression of a raiA motif gene from a plasmid. These results demonstrate that raiA motif RNAs normally participate in major cell differentiation processes by operating as a trans-acting factor.

Granulicatella elegans infective endocarditis, a rare case report at a secondary teaching hospital, Tangerang, Indonesia

Granulicatella elegans (G. elegans) is a Gram-positive facultative anaerobe and one type of Nutritionally Variant Streptococci (NVS) normally role as normal flora in human body, for example oral cavity. Rarely had this colony become infective compared to other Granulicatella.

First Isolation of Bacillus licheniformis from Bovine Mastitis in Iran.

Bacillus licheniformis is a gram-positive, endospore-forming, saprophytic and facultative anaerobe that is resistant to heat and environmental conditions. This study was the first to isolate and confirm B. licheniformis as a cause of bovine mastitis in Iran. In the summer of 2020, 105 samples of mastitic milk were collected from dairy farms around Tehran and sent to the microbiology laboratory of the Faculty of Veterinary Medicine at the University of Tehran. The bacterial pathogens were identified using selective and differential culture media and confirmed by PCR to contain the toxin synthetase genes licA, licB and licC in mastitic isolates of B. licheniformis. Resistance patterns to 19 antibiotics were determined for two isolates of B. licheniformis. Staphylococcus aureus and Escherichia coli were identified as the most important organisms in the samples. B. licheniformis was isolated from the two samples containing all three genes. Both isolates were resistant to streptomycin, trimethoprim-sulfamethoxazole, cefixime, ampicillin, bacitracin, clindamycin, and gentamicin. B. licheniformis was reported for the first time in Iran as a cause of bovine mastitis with clinical symptoms. The first isolation of toxin-producing strains of B. licheniformis from mastitic cows in Iran raises concerns about the safety of dairy products. In principle, selected strains with toxigenic potential should not be used as feed additives and animal feed. However, whole genome sequencing is proposed to search for genes coding for toxins.

Is maxillary sinusitis and radiographic maxillary sinus opacification associated with an altered microbiology of MRONJ?

ObjectiveMaxillary sinusitis can be a sequela of medication-related osteonecrosis of the jaw (MRONJ). This study aims to characterize the microbiome of maxillary MRONJ with concurrent maxillary sinusitis and radiographic maxillary sinus opacification to determine if there is a relationship between the microbiome of MRONJ and sinus disease. Study DesignThis retrospective case series was conducted using electronic health records from the University of Pennsylvania and affiliated hospitals. The target population was surgically managed maxillary MRONJ patients. The primary predictor variables were tissue culture results. The primary outcomes were maxillary sinusitis or maxillary sinus opacification. Statistical analysis was performed using chi-squared tests at the 95% confidence interval. ResultsThirty-nine subjects were selected: 25 had sinus opacification and 11 had sinusitis. Resident bacteria were present in 90% of subjects, non-resident bacteria in 74%, and opportunistic organisms in 15%. There were significantly more subjects with chronic sinusitis microbes (79%) than without. There were significantly more gram-positive anaerobes, specifically Propionibacterium, as well as the gram-negative facultative anaerobe, Capnocytophaga, in subjects with concurrent sinusitis. ConclusionsMaxillary MRONJ with concurrent maxillary sinusitis may be associated with gram-positive anaerobic species, Propionibacterium, and Capnocytophaga colonization. Maxillary MRONJ patients may benefit from sinus evaluation and concurrent surgical intervention.

A nine-year facility-based review of the pattern and outcome of neonatal tetanus in Ondo State, Nigeria

Tetanus is an infection caused by the Clostridium tetani; a ubiquitous Gram-positive, motile, spore-forming, and toxin-producing anaerobe. It is the only vaccine-preventable infection that is not communicable and which is still causing regrettable morbidity and mortality in newborns in Nigeria. The objective of this study was to review the pattern of neonatal tetanus infection and to document its outcome in a secondary health care level in South-west Nigeria. This was a hospital-based prospective study. Questionnaires were also administered to collect information from the parents. Out of a total of 4,277 out-born babies, 23 had Neonatal Tetanus (NNT). The mean incubation period was 6.62±2.2 days; the period of onset was less than 24 hours in 9 (39.1%) of the babies and greater than 24 hours in 14 (60.9%) babies. Four babies (17.4%) died, 4 (17.4%) left against medical advice, and the mean age at death was 11.7±3.5 days. Other clinical records showed that 56.5% of mothers did not receive antenatal care or tetanus toxoid, 65.2% had non-hospital deliveries, cord care was sub-optimal in the majority of cases, and the case fatality ratio was 17.4%. The study reveals that NNT still contributes to morbidities and mortalities among Nigerian neonates. The incidence per year, though, waxes and wanes with no particular pattern; the disease still has the tendency to dip the neonatal indices.

Staphylococcus epidermidis.

Species of the bacterial genus Staphylococcus are classified clinically based on their ability to produce the enzyme coagulase which clots plasma by binding to prothrombin, facilitating the conversion of fibrinogen to fibrin. Many coagulase-negative staphylococci (CoNS), including Staphylococcus epidermidis, are found on the skin and primarily function as human commensals. S. epidermidis is a Gram-positive facultative anaerobe that is universally found on humans and is ubiquitously present on the skin and frequently found in the nasopharynx.

P-104 Impact of Semen Microbiota on the Embryo Quality

Abstract Study question Is there a relationship between the microbiota composition of semen samples used for assisted reproductive technologies (ART) and quality of embryos? Summary answer The obligate anaerobes prevalence in semen microbiota was associated with reduced embryo quality in patients with astenozoospermia, but no difference was found for normozoospermic samples. What is known already The success of the ART depends on a number of factors, including embryo quality. The viability of IVF embryo could be affected by various environmental factors, including contamination with semen microbiota. Semen is not sterile, and even processed it may contain some bacteria, which may colonize culture dishes with oocytes and embryos. It was shown that the presence of bacteria might alter the sperm quality and the contamination of embryo culture dishes with bacteria was associated with poor quality of the developing embryos. Study design, size, duration 126 infertile couples attending the “Garmonia” Medical Center (Yekaterinburg, Russia) for IVF in 2020-2021, were included in the study. Depending on the spermiogram results, they were divided into two groups Group 1 (n = 51) — asthenozoospermia, Group 2 (n = 75) — normospermia. Participants/materials, setting, methods Semen microbiota was analyzed using RT-PCR kit Androflor (DNA-Technology, Russia). Cluster analysis was performed for 78 samples with the total bacterial load (TBL) of at least 103 GE/ml (asthenozoospermia = 31, normozoospermia = 47). Cluster analysis was conducted using the k-means ++ algorithm, scikit-learn. The blastocyst development rate (BDR), as the proportion of 2PN zygotes, was determined on day 5 after injection. BDR ≥ 40% was considered satisfactory, BDR < 40% - unsatisfactory. Main results and the role of chance When analyzing semen microbiota, 8 stable clusters were distinguished. Cluster 1 was lactobacilli-dominated, Cluster 2 and 3 - Gram-positive facultative anaerobes dominated with prevalence of Corynebacterium spp. and Streptococcus spp. respectively; Cluster 4 –Enterobacteriaceae/Enterococcus spp-dominated,; Cluster 5, 6 - obligate anaerobes dominated with prevalence of Bacteroides spp./Porphyromonas spp./Prevotella spp. or Peptostreptococcus spp./Parvimonas spp., respectively. Cluster 7 was formed by mixed obligate anaerobes (MOA); Cluster 8 - by Mycoplasmae. There was no difference in detection rate of individual clusters in samples with normospermia and asthenozoospermia. Depending on their BDR each group were divided into subgroups: Subgroup 1A (n = 25) with BDR ≥ 40%, Subgroup 1B (n = 26) with BDR < 40%; Subgroup 2A (n = 38) with BDR ≥ 40%, Subgroup 2B (n = 37) with BDR < 40%. The detection rate of different microbiota clusters in Subgroups 2A and 2B (normospermia samples) was almost similar. In asthenozoospermia samples the lower embryo quality (Subgroup 1B) was associated with higher prevalence of Cluster 7 (53.8%) comparing to those of Subgroup 1A (16.0%), p < 0.001. Cluster 1 was detected more often in Subgroup 1A (20.0%) than in Subgroup 1B (7.8%), but p > 0.05. TBL > 103 GE/ml was present in 52% of Subgroup 1A samples and in 69.2% of Subgroup 1B samples. Limitations, reasons for caution Cluster analysis was not conducted for the samples with TBL lower than 103 GE/ml, since their results were incompatible with the data received for the negative control samples. Wider implications of the findings Further research could determine the significance of the described bacterial clusters in semen with other pathologies. Establishing the relationship between the characteristics of semen microbiota and poor embryo quality might allow the development of new algorithms for treating patients with reproductive disorders, depending on the composition of semen microbiota. Trial registration number not applicable

Comparative evaluation of MALDI-TOF MS and 16S rRNA gene sequencing for the identification of clinically relevant anaerobic bacteria: critical evaluation of discrepant results

ObjectivesThe main study objective was to evaluate the correlation between matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing results for the identification of anaerobes. MethodsA retrospective study was conducted of all anaerobic bacteria isolated from clinically significant specimens. MALDI-TOF (Bruker Byotyper) and 16S rRNA gene sequencing were performed in all strains. Identifications were considered correct when the concordance with gene sequencing was ≥99%. ResultsThe study included 364 isolates of anaerobic bacteria: 201 (55.2%) Gram-negative and 163 (44.8%) Gram-positive, mostly belonging to the genus Bacteroides. Isolates were largely obtained from blood cultures (128/35.4%) and intra-abdominal samples (116/32.1%). Overall, 87.3% of isolates were identified at species level using the version 9 database (89.5% of Gram-negative and 84.6% of Gram-positive anaerobic bacteria). All isolates belonging to the species B. fragilis sensu stricto were correctly identified by MALDI-TOF MS, but five cases of Phocaeicola (Bacteroides) dorei were misidentified as Phocaeicola (Bacteroides) vulgatus; all Prevotella isolates were correctly identified at the genus level, and most were correctly identified at the species level. Among Gram-positive anaerobes, 12 Anaerococcus species were not identified by MALDI-TOF MS, while six cases identified as Peptoniphilus indolicus were found to belong to other genera/species. ConclusionsMALDI-TOF is a reliable technique for identifying most anaerobic bacteria, although the database needs frequent updating to identify rare, infrequent, and newly discovered species.

Enterococcus Species: A Systemic Review

Enterococci are gram-positive facultative anaerobes, these are commensals in the intestinal system of numerous animals, including humans. They affect hospitalized patients and cause nosocomial infections, respiratory infections, endocarditis, wound infections, UTIs, and other enterococcal infections. This discovery can be explained by hemolysin, gelatinase, aggregation substances, hyaluronidase, capsular polysaccharides, and cell wall carbohydrate. Various enterococcal spp. include Enterococcus avium Vancomycin resistance was acquired by enterococci throughout the antibacterial spectrum, primary antibiotic used regimen based on dual β lactams and aminoglycosides.

Differences between bloodstream infections involving Gram-positive and Gram-negative anaerobes

BackgroundThe objectives of this study were to describe differences between bloodstream infections involving Gram-positive (GP) and Gram-negative (GN) anaerobic bacteria. MethodsPatients with clinically significant anaerobic bacteremia detected between October 2016 and July 2022 in a tertiary hospital in Granada (Spain) were retrospectively included. Species identification was performed by MALDI-TOF MS and/or molecular methods. The association between variables was analyzed using contingency tables, applying the chi-square test when expected frequencies were adequate and the Fisher exact test when not. Variables were gathered at the time of the first positive blood culture. ResultsOut of 237 cases of anaerobic bloodstream infections detected, 127 (53.6%) were GN. Crude mortality was 20.3%, corresponding to 48 patients who died of causes directly attributable to bacteremia. The presence of malignant disease (p = 0.011), abdominal and/or pelvic surgery (p = 0.001), and transplantation (p = 0.008) were significantly associated with bacteremia due to GN bacteria, while the presence of diabetes mellitus was significantly associated with bacteremia due to GP bacteria (p = 0.022). The presence of both septic shock and mortality was more frequently associated with bacteremia due to GN versus GP bacteria. ConclusionsThe association of certain variables with the presence of bloodstream infections due to GP or GN anaerobic bacteria may assist in selecting the optimal empirical therapeutic approach and improving the outcome of patients with these types of infection.

Daya Antibakteri Ekstrak Kulit Buah Kakao (Theobroma cacao L.) sebagai Alternatif Bahan Irigasi Saluran Akar terhadap Streptococcus viridans

Streptococcus viridans is a Gram-positive facultative anaerobe that most commonly found in infected root canals. The biomechanical preparation of root canal treatment requires root canal irrigation as it functions not only used to cleanser but also antibacterial agent. NaOCl 2,5% is the most commonly used Endodontic irrigant, however it is still considered to have several disadvantages. Cocoa pod shell (Theobroma cacao L.) are industrial plantation waste which has a source of antibacterial compounds that expected to be an alternative to substitute NaOCl’s drawbacks. This study aim to examine the antibacterial effectiveness of cocoa pod shell extract against S.viridans. The research is posttest only group control design and the method use broth dilution to examine the antibacterial effectiveness. The results of Kolmogorov-Smirnov test and Levene's test showed that data set which exhibited both non-normally distributed and non-homogeneous, continued with the nonparametric test using the Kruskal-wallis test, it was found that p <0.5 meant there were significantly differences between all study groups. 25%; 12,5%; 6,25%; 3,125%; 1,56%; 0,78% concentration of cocoa pod shell extract has antibacterial activity against S.viridans. The Minimum Inhibitory Concentration to against S.viridans is cocoa pod shell extract concentration 0,78%. Cocoa pod shell extract concentration 12,5% and 25% equal to NaOCL 2,5%.

Sarecycline inhibits protein translation in Cutibacterium acnes 70S ribosome using a two-site mechanism.

Acne vulgaris is a chronic disfiguring skin disease affecting ∼1 billion people worldwide, often having persistent negative effects on physical and mental health. The Gram-positive anaerobe, Cutibacterium acnes is implicated in acne pathogenesis and is, therefore, a main target for antibiotic-based acne therapy. We determined a 2.8-Å resolution structure of the 70S ribosome of Cutibacterium acnes by cryogenic electron microscopy and discovered that sarecycline, a narrow-spectrum antibiotic against Cutibacterium acnes, may inhibit two active sites of this bacterium's ribosome in contrast to the one site detected previously on the model ribosome of Thermus thermophilus. Apart from the canonical binding site at the mRNA decoding center, the second binding site for sarecycline exists at the nascent peptide exit tunnel, reminiscent of the macrolides class of antibiotics. The structure also revealed Cutibacterium acnes-specific features of the ribosomal RNA and proteins. Unlike the ribosome of the Gram-negative bacterium Escherichia coli, Cutibacterium acnes ribosome has two additional proteins, bS22 and bL37, which are also present in the ribosomes of Mycobacterium smegmatis and Mycobacterium tuberculosis. We show that bS22 and bL37 have antimicrobial properties and may be involved in maintaining the healthy homeostasis of the human skin microbiome.

Limosilactobacillus walteri sp. nov., a novel probiotic antimicrobial lipopeptide producing bacterium.

A Gram-positive facultative anaerobe, non-spore forming, and non-motile bacterial strain M31 was isolated from faecal contaminated soil. The strain is previously reported to produce a novel antimicrobial lipopeptide and displayed probiotic properties. The strain M31 is catalase negative and fermented D-galactose, D-glucose, esculin, D-maltose, D-lactose, D-melibiose, D-raffinose, D-saccharose (weak reaction), D-xylose (weak reaction), D-ribose (weak reaction), and L-arabinose (weak reaction). The majority of fatty acids were C16:0 (53.9%), C18:0 (26.9%), and C19:0 cyclo ω8c (19.1%). The genome is 2234040bp long with 38.81% GC content. The pairwise ortho average nucleotide identity and digital DNA-DNA hybridisation values of strain M31 with its closest relative species from Lm. reuteri clade and Lm. rudii is below the recommended cut-off of 95% and 70% respectively. Herein, we propose Limosilactobacillus walteri sp. nov. as a novel species of the genus Limosilactobacillus with M31=MTCC 12838=JCM 32759=KCTC 25569.