Synchronization of Mycobacterium life cycle: A possible novel mechanism of antimycobacterial drug resistance evolution and its manipulation.

Mycobacterium Tuberculosis (Mtb) causing Tuberculosis (TB) is a widespread disease infecting millions of people worldwide. Additionally, emergence of drug resistant tuberculosis is a major challenge and concern in high TB burden countries. Most of the drug resistance in mycobacteria is attributed to developing acquired resistance due to spontaneous mutations or intrinsic resistance mechanisms. In this review, we emphasize on the role of bacterial cell cycle synchronization as one of the intrinsic mechanisms used by the bacteria to cope with stress response and perhaps involved in evolution of its drug resistance. The importance of cell cycle synchronization and its function in drug resistance in cancer cells, malarial and viral pathogens is well understood, but its role in bacterial pathogens has yet to be established. From the extensive literature survey, we could collect information regarding how mycobacteria use synchronization to overcome the stress response. Additionally, it has been observed that most of the microbial pathogens including mycobacteria are responsive to drugs predominantly in their logarithmic phase, while they show resistance to antibiotics when they are in the lag or stationary phase. Therefore, we speculate that Mtb might use this novel strategy wherein they regulate their cell cycle upon antibiotic pressure such that they either enter in their low metabolic phase i.e., either the lag or stationary phase to overcome the antibiotic pressure and function as persister cells. Thus, we propose that manipulating the mycobacterial drug resistance could be possible by fine-tuning its cell cycle.

Acquired rifamycin resistance among patients with tuberculosis and HIV in new York City, 2001-2023.

Introduction: Acquired rifamycin resistance (ARR) in tuberculosis (TB) has been associated with HIV infection and can necessitate complicated TB treatment regimens, particularly in people living with HIV (PLWH). This work examines clinical characteristics and treatment outcomes of PLWH who developed ARR from 2001 to 2023 in New York City (NYC) to inform best practices for treating these patients. Methods: PLWH who developed ARR 2001-2023 were identified from the NYC TB registry. Results: Sixteen PLWH developed ARR; 15 were diagnosed 2001-2009 and the 16th was diagnosed in 2017. Median CD4 count was 48/mm3. On initial presentation, 14 had positive sputum cultures; of these, 12 culture-converted prior to developing ARR. Ten patients completed a course of TB treatment but subsequently relapsed; in six of these cases, ARR was discovered upon relapse, triggering treatment with a non-rifamycin-containing regimen, while in the other four, ARR was discovered during a second round of rifamycin-containing treatment. Three patients were lost to follow-up during their initial course of TB treatment and later returned to care; after being restarted on a rifamycin-containing regimen, ARR was discovered. Finally, three patients culture-converted during their first course of treatment but subsequently had cultures that grew rifamycin-resistant Mycobacterium tuberculosis prior to treatment completion, leading to changes in their treatment regimens. Among the 16 patients, eight died before being cured of TB, seven successfully completed treatment, and one was lost to follow-up. Conclusions: PLWH should be monitored closely for the development of ARR during treatment for TB, and sputum culture conversion should be interpreted cautiously in this group. Collecting a final sputum sample may be especially important for PLWH, as treatment failure and relapse were common in this population. The decrease in the number of cases of ARR among PLWH during the study period may reflect the decrease in the total number of PLWH diagnosed with TB in NYC in recent years, improved immune status of PLWH due to increased uptake of antiretroviral drugs, and improvements in the way anti-TB regimens are designed for PLWH (such as recommending daily rather than intermittent rifamycin dosing).

Pharmacotherapeutic Considerations in the Treatment of Nontuberculous Mycobacterial Infections: A Primer for Clinicians.

Nontuberculous mycobacteria (NTM) can cause a variety of infections, including serious pulmonary disease. Treatment encompasses polypharmacy, with a targeted regimen of 2-5 active medications, depending on site of infection, species, and clinical characteristics. Medications may include oral, intravenous, and inhalational routes. Medication acquisition can be challenging for numerous reasons, including investigational status, limited distribution models, and insurance prior authorization. Additionally, monitoring and managing adverse reactions and drug interactions is a unique skill set. While NTM is primarily medically managed, clinicians may not be familiar with the intricacies of medication selection, procurement, and monitoring. This review offers insights into the pharmacotherapeutic considerations of this highly complex disease state, including regimen design, medication acquisition, safety monitoring, relevant drug-drug interactions, and adverse drug reactions.

Chemical profile, antituberculosis, DSC, and molecular docking studies of Mentha longifolia essential oil.

The volatile profile of Mentha longifolia was observed using GC-MS, GC-FID, FT-IR and 13CNMR. Twenty-two constituents were found to be present in this essential oil, accounting 96.04 (%) of total essential oil and oxegenated monoterpenes were major class of compounds. The key constituents of this essential oil were pieritenone oxide (45.9%), piperitone (17.5%), beta caryophyllene (10.2%), and Germacrene D (5.0%). FT-IR showed peak at 1669 and 1707 cm-1 which may be due to the presence of carbonyl groups. Among the tested compounds, Germacrene D showed highest binding affinity value of -6.8 kcal mol-1 and a pKi value of 6.01. The dsc studies revealed that boiling point of this EO is above 200 °C. Microplate Alamar Blue assay (MABA) was carried out for the assessment of antimycobacterial activity using isoniazid and nicotinic as reference compound and oil was found to be active within conc. range of 0.8-1.6 µg/mL against mycobacterium tuberculosis, hence can act as a potential candidate against antituberculosis.

Biofilm Formation in Mycobacterial Genus; Mechanism of Biofilm Formation and Anti-Mycobacterial Biofilm Agents.

Mycobacterium tuberculosis, Mycobacterium leprae, and non-tuberculous mycobacteria (NTM) are among the most significant human pathogens within the Mycobacterium genus. These pathogens can infect people who come into contact with biomaterials or have chronic illnesses. A characteristic pathogenic trait of mycobacteria is the development of biofilms, which involves several molecules, such as the GroEL1 chaperone, glycopeptidolipids, and shorter-chain mycolic acids. Bacterial behavior is influenced by nutrients, ions, and carbon sources, which also play a regulatory role in biofilm development. Compared to their planktonic phase, mycobacterial biofilms are more resilient to environmental stresses and disinfectants. Mycobacteria that produce biofilms have been found in several environmental studies, particularly in water systems. NTM can cause respiratory problems in individuals with underlying illnesses such as cystic fibrosis, bronchiectasis, and old tuberculosis scars. Mycobacteria that grow slowly, like those in the Mycobacterium avium complex (MAC), or rapidly, like Mycobacterium abscessus, can be pathogens. Infections related to biomaterials represent a significant category of biofilm-associated infections, with rapidly growing mycobacteria being the most frequently identified organisms. A biofilm produced by M. tuberculosis can contribute to caseous necrosis and cavity formation in lung tissue. Additionally, M. tuberculosis forms biofilms on clinical biomaterials. Biofilm formation is a major contributor to antimicrobial resistance, providing defense against drugs that would typically be effective against these bacteria in their planktonic state. The antibiotic resistance of biofilm-forming microbes may render therapy ineffective, necessitating the physical removal of biofilms to cure the infection. Recently, new approaches have been developed with potential anti-biofilm compounds to increase treatment effectiveness. Understanding biofilms is crucial for the appropriate treatment of various NTM diseases, and the recent discovery of M. tuberculosis biofilms has opened up a new field of study. This review focuses on the biofilm formation of the Mycobacterial genus, the mechanisms of biofilm formation, and anti-mycobacterial biofilm agents.

Mycobacterial Targets for Thiourea Derivatives: Opportunities for Virtual Screening in Tuberculosis Drug Discovery.

Tuberculosis (TB) remains a primary global health concern, necessitating the discovery and development of new anti-TB drugs, mainly to combat drug-resistant strains. In this context, thiourea derivatives have emerged as promising candidates in TB drug discovery due to their diverse chemical structures and pharmacological properties. This review aimed to explore this potential, identifying and exploring molecular targets for thiourea derivatives in Mycobacterium tuberculosis (Mtb) and the potential application of virtual screening techniques in drug discovery. We have compiled a comprehensive list of possible molecular targets of thiourea derivatives in Mtb. The enzymes are primarily involved in the biosynthesis of various cell wall components, including mycolic acids, peptidoglycans, and arabinans, or targets in the branched-chain amino acid biosynthesis (BCAA) pathway and detoxification mechanisms. We discuss the potential of these targets as critical constituents for the design of novel anti-TB drugs. Besides, we highlight the opportunities that virtual screening methodologies present in identifying potential thiourea derivatives that can interact with these molecular targets. The presented findings contribute to the ongoing efforts in TB drug discovery and lay the foundation for further research in designing and developing more effective treatments against this devastating disease.

A Review of the Potential of Poly-(lactide-co-glycolide) Nanoparticles as a Delivery System for an Active Antimycobacterial Compound, 7-Methyljuglone.

7-Methyljuglone (7-MJ) is a pure compound isolated from the roots of Euclea natalensis A. DC., a shrub indigenous to South Africa. It exhibits significant promise as a potential treatment for the highly communicable disease tuberculosis (TB), owing to its effective antimycobacterial activity against Mycobacterium tuberculosis. Despite its potential therapeutic benefits, 7-MJ has demonstrated in vitro cytotoxicity against various cancerous and non-cancerous cell lines, raising concerns about its safety for consumption by TB patients. Therefore, this review focuses on exploring the potential of poly-(lactide-co-glycolic) acid (PLGA) nanoparticles as a delivery system, which has been shown to decrease in vitro cytotoxicity, and 7-MJ as an effective antimycobacterial compound.

Metformin has immunomodulatory effects which support its potential use as adjunctive therapy in tuberculosis.

Metformin is the preferred oral medication for patients with type 2 diabetes mellitus, and this blood glucose-lowering and insulin-sensitizing drug has immunomodulatory effects that could contribute to the management of patients with various other autoimmune and infectious diseases. Tuberculosis is one such infection, and it remains prevalent worldwide, largely due to the successful evasion of the host's immune responses by the infecting pathogen, Mycobacterium tuberculosis. This review focuses on the possible mechanisms relevant to metformin's modulation of innate and adaptive immune responses to Mycobacterium tuberculosis and its potential use as an adjunctive drug in the treatment of tuberculosis. Current data suggest that metformin increases autophagy, phagocytosis, and mitochondrial reactive oxygen species production, while limiting excess inflammation and tissue destruction. This multifaceted drug also augments cell-mediated immune responses by maintaining CD8+ T cell metabolic homeostasis and improving immunological memory. Several murine models have demonstrated that metformin can reduce tuberculosis severity and tissue pathology, and two in vitro human studies confirmed enhanced immune responses in metformin-treated cells. These studies provide convincing evidence supporting the use of metformin to augment immune responses in patients with tuberculosis.

Ligand-based virtual screening and biological evaluation of inhibitors of Mycobacterium tuberculosis H37Rv.

Novel antimycobacterial compounds are needed to expand the existing toolbox of therapeutic agents, which sometimes fail to be effective. In our study we extracted, filtered, and aggregated the diverse data on antimycobacterial activity of chemical compounds from the ChEMBL database version 24.1. These training sets were used to create the classification and regression models with PASS and GUSAR software. The IOC chemical library consisting of approximately 200,000 chemical compounds was screened using these (Q)SAR models to select novel compounds potentially having antimycobacterial activity. The QikProp tool (Schrödinger) was used to predict ADME properties and find compounds with acceptable ADME profiles. As a result, 20 chemical compounds were selected for further biological evaluation, of which 13 were the Schiff bases of isoniazid. To diversify the set of selected compounds we applied substructure filtering and selected an additional 10 compounds, none of which were Schiff bases of isoniazid. Thirty compounds selected using virtual screening were biologically evaluated in a REMA assay against the M. tuberculosis strain H37Rv. Twelve compounds demonstrated MIC below 20 µM (ranging from 2.17 to 16.67 µM) and 18 compounds demonstrated substantially higher MIC values. The discovered antimycobacterial agents represent different chemical classes.

Synthesis and Evaluation of Novel Substituted N-Aryl 1,4-Dihydropyridines as Antituberculostatic Agents.

BACKGROUND: Tuberculosis has been the main cause of mortality of infectious diseases worldwide, with strongly limited therapeutic options. With increasing resistance and missing suitable drugs in those cases, there is a strong need for novel antituberculostatic drugs. We developed novel N-aryl 1,4-dihydropyridines with various substitution patterns to evaluate them as antituberculostatic agents. METHODS: 1,4-Dihydropyridine derivatives were synthesized and purified by column chromatography or recrystallization. The mycobacterial growth inhibition was determined in a fluorescent mycobacterial growth assay. RESULTS: The compounds were prepared in a simple one-pot reaction under acidic conditions with structurally varied components. The substituent effects on the determined mycobacterial growth inhibitory properties are discussed. CONCLUSION: Lipophilic diester substituted derivatives show promising activities that were additionally affected by the aromatic substituent functions. Thus, we identified compounds with activities almost reaching that of the used antimycobacterial drug as control.

Novel indolinone-tethered benzothiophenes as anti-tubercular agents against MDR/XDR M. tuberculosis: Design, synthesis, biological evaluation and in vivo pharmacokinetic study.

Joining the global effort to eradicate tuberculosis, one of the deadliest infectious killers in the world, we disclose in this paper the design and synthesis of new indolinone-tethered benzothiophene hybrids 6a-i and 7a-i as potential anti-tubercular agents. The MICs were determined in vitro for the synthesized compounds against the sensitive M. tuberculosis strain ATCC 25177. Potent compounds 6b, 6d, 6f, 6h, 7a, 7b, 7d, 7f, 7h and 7i were furtherly assessed versus resistant MDR-TB and XDR-TB. Structure activity relationship investigation of the synthesized compounds was illustrated, accordingly. Superlative potency was unveiled for compound 6h (MIC = 0.48, 1.95 and 7.81 µg/mL for ATCC 25177 sensitive TB strain, resistant MDR-TB and XDR-TB, respectively). Moreover, validated in vivo pharmacokinetic study was performed for the most potent derivative 6h revealing superior pharmacokinetic profile over the reference drug. For further exploration of the anti-tubercular mechanism of action, molecular docking was carried out for the former compound in DprE1 active site as one of the important biological targets of TB. The binding mode and the docking score uncovered exceptional binding when compared to the co-crystallized ligand suggesting that it maybe the underlying target for its outstanding anti-tubercular potency.

Targeting of essential mycobacterial replication enzyme DnaG primase revealed Mitoxantrone and Vapreotide as novel mycobacterial growth inhibitors.

Tuberculosis (TB) is the second leading cause of mortality after COVID-19, with a global death toll of 1.6 million in 2021. The escalating situation of drug-resistant forms of TB has threatened the current TB management strategies. New therapeutics with novel mechanisms of action are urgently required to address the current global TB crisis. The essential mycobacterial primase DnaG with no structural homology to homo sapiens presents itself as a good candidate for drug targeting. In the present study, Mitoxantrone and Vapreotide, two FDA-approved drugs, were identified as potential anti-mycobacterial agents. Both Mitoxantrone and Vapreotide exhibit a strong Minimum Inhibitory Concentration (MIC) of ≤25µg/ml against both the virulent (M.tb-H37Rv) and avirulent (M.tb-H37Ra) strains of M.tb. Extending the validations further revealed the inhibitory potential drugs in ex vivo conditions. Leveraging the computational high-throughput multi-level docking procedures from the pool of ~2700 FDA-approved compounds, Mitoxantrone and Vapreotide were screened out as potential inhibitors of DnaG. Extensive 200 ns long all-atoms molecular dynamic simulation of DnaGDrugs complexes revealed that both drugs bind strongly and stabilize the DnaG during simulations. Reduced solvent exposure and confined motions of the active centre of DnaG upon complexation with drugs indicated that both drugs led to the closure of the active site of DnaG. From this study's findings, we propose Mitoxantrone and Vapreotide as potential anti-mycobacterial agents, with their novel mechanism of action against mycobacterial DnaG.

Distribution of multi-drug resistant tuberculosis in Ekiti and Ondo states, Nigeria.

Background: Tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB), is one of the top infectious killer diseases in the world. The emergence of drug-resistant MTB strains has thrown challenges in controlling TB worldwide. This study investigated the prevalence of drug-resistant tuberculosis in the states of Nigeria and the risk factors that can increase the incidence of tuberculosis. Methods: The study is a cross-sectional epidemiological research carried out in the six senatorial districts of Ekiti and Ondo states, Nigeria, between February 2019 and January 2020. A structured questionnaire was administered to 1203 respondents for socio-demographic information, and sputum samples were collected from them for TB investigation. GeneXpert technique was used to diagnose TB from the sputum samples, followed by bacterial isolation using Löweinstein-Jensen medium and antibiotic susceptibility testing. Results: Prevalence of TB in the two states combined was 15 â€‹%; with 13.8 â€‹% for Ekiti state and 16.1 â€‹% for Ondo State. The distribution of TB in the senatorial districts was such that: Ondo South â€‹> â€‹Ekiti Central â€‹> â€‹Ekiti South â€‹> â€‹Ondo North â€‹> â€‹Ekiti North â€‹> â€‹Ondo Central. The risk factors identified for TB prevalence in two states were gender, male â€‹> â€‹female (OR â€‹= â€‹0.548, p â€‹= â€‹0.004); overcrowding (OR â€‹= â€‹0.733, p â€‹= â€‹0.026); room size (OR â€‹= â€‹0.580, p â€‹= â€‹0.002); smoking (OR â€‹= â€‹0.682, p â€‹= â€‹0.019) and dry and dusty season (OR â€‹= â€‹0.468, p â€‹= â€‹0.005). The prevalence of MDR-TB in Ekiti and Ondo States were 1.2 â€‹% and 1.3 â€‹% respectively. The identified risk factors for MDR were education (OR â€‹= â€‹0.739, p â€‹= â€‹0.017), age (OR â€‹= â€‹0.846, p â€‹= â€‹0.048), religion (OR â€‹= â€‹1.95, p â€‹= â€‹0.0003), family income (OR â€‹= â€‹1.76, p â€‹= â€‹0.008), previous TB treatment (OR â€‹= â€‹3.64, p â€‹= â€‹0.004), smoking (OR â€‹= â€‹1.33, p â€‹= â€‹0.035) and HIV status (OR â€‹= â€‹1.85, p â€‹= â€‹0.006). Rifampicin monoresistant was reported in 6.7 â€‹% of the rifampicin-resistant strains, while 93.3 â€‹% were rifampicin polyresistant strains. Two (13.3 â€‹%) of the MDR-TB strains were resistant to all the 3 first-line antimycobacterial agents. All the Rifampicin-resistant TB strains were susceptible to the aminoglycosides (Amikacin, Capreomycin and Kanamycin), also with high susceptibility to the fluoroquinilones: Moxifloxacin (100 â€‹%) and Levofloxacin (86.7 â€‹%). Sixteen (94.1 â€‹%) of the 17 Rifampicin-susceptible strains were susceptible to all the eight antibiotics tested, while one (5.9 â€‹%) was susceptible to Rifampicin and Isoniazid but resistant to the rest antibiotics. Conclusion: The study showed that there is high prevalence of TB and MDR-TB in Ekiti and Ondo States Nigeria, hence, to meet the SDG Target 3.3 of ending TB epidemic by 2030, culturing and antibiotic susceptibility testing should be carried out on every TB-positive sputum and the patients treated accordingly.

Tailoring selective triclosan azo-adducts: Design, synthesis, and anti-mycobacterial evaluation.

A series of triclosan azo-adducts were synthesized to investigate their structure-activity relationship against Mycobacterium tuberculosis and non-tuberculous mycobacteria. The series' most potent compound was four and sixteen times more active than triclosan and rifabutin against drug-resistant Mycobacterium abscessus, respectively, while being less cytotoxic to human macrophages than triclosan on day one. Additionally, one of the azo-adducts was twice as efficient against M. tuberculosis as triclosan and twice as effective against Mycobacterium marinum as isoniazid. Furthermore, the synthesized azo-adducts were equally effective against M. abscessus strains overexpressing InhA, suggesting that these compounds work through a distinct mechanism.

N-Pyrazinylhydroxybenzamides as biologically active compounds: a hit-expansion study and antimicrobial evaluation.

Background: The development of novel antimicrobial drugs is an essential part of combatting the uprising of antimicrobial resistance. Proper hit-to-lead development is crucially needed. Methods & results: We present a hit-expansion study of N-pyrazinyl- and N-pyridyl-hydroxybenzamides with a comprehensive determination of structure-activity relationships. The antimicrobial screening revealed high selectivity to staphylococci along with antimycobacterial activity with the best value of 6.25 µg/ml against Mycobacterium tuberculosis H37Rv. We proved an inhibition of proteosynthesis and a membrane depolarization of methicillin-resistant Staphylococcus aureus. Conclusion: Our results are a good starting point for further development of new antimicrobial compounds, where the next step would be tuning the potential between relatively nonspecific membrane depolarization effect and specific inhibition of proteosynthesis.

Expanding the squaramide library as mycobacterial ATP synthase inhibitors: Innovative synthetic pathway and biological evaluation.

Mycobacterial ATP synthase is a validated therapeutic target for combating drug-resistant tuberculosis. Inhibition of this enzyme has been featured as an efficient strategy for the development of new antimycobacterial agents against drug-resistant pathogens. In this study, we synthesised and explored two distinct series of squaric acid analogues designed to inhibit mycobacterial ATP synthase. Among the extensive array of compounds investigated, members of the phenyl-substituted sub-library emerged as primary hits. To gain deeper insights into their mechanisms of action, we conducted advanced biological studies, focusing on the compounds displaying a direct binding of a nitrogen heteroatom to the phenyl ring, resulting in the highest potency. Our investigations into spontaneous mutants led to the validation of a single point mutation within the atpB gene (Rv1304), responsible for encoding the ATP synthase subunit a. This genetic alteration sheds light on the molecular basis of resistance to squaramides. Furthermore, we explored the possibility of synergy between squaramides and the reference drug clofazimine using a checkerboard assay, highlighting the promising avenue for enhancing the effectiveness of existing treatments through combined therapeutic approaches. This study contributes to the expansion of investigating squaramides as promising drug candidates in the ongoing battle against drug-resistant tuberculosis.

Polyoxygenated cyclohexene derivatives and other constituents of Uvaria rufa stem.

Six undescribed compounds, uvarirufols D and E, (+)-uvarigranol B, (-)-uvarigranol E, 6-acetoxy-5-hydroxy-7-methoxyflavanone and cherrevenaphthalene D, along with twelve known compounds, including polyoxygenated cyclohexenes, flavonoids, and lignans, were isolated from the methanol extract of Uvaria rufa stems. Their structures were elucidated by spectroscopic analyses and the absolute configurations were determined using electronic circular dichroism. Several isolates were evaluated for cytotoxic, antitubercular and anti-inflammatory potentials. (-)-6-Acetylzeylenol showed moderate inhibitory activity against Mycobacterium tuberculosis, with MIC value of 47.10 µg/mL. Cherrevenaphthalene D exhibited weak antimycobacterial activity and potent inhibitory effect on lipopolysaccharide-induced nitric oxide (NO) production in RAW 264.7 cells (EC50 = 8.54 µM). 8-Hydroxy-5,7-dimethoxyflavanone displayed moderate level of NO inhibition (EC50 = 43.62 µM) with little cytotoxicity. The polyoxygenated cyclohexenes and lignans were inactive against HCT 116 and 22Rv1 cancer cells (IC50 > 100 µM).

Design and synthesis of benzofuran- and naphthalene-fused thiazinones as antimycobacterial agents.

Benzothiazinones (BTZs) have widely inspired medicinal chemistry and translational research due to their remarkable antitubercular potency and clinical potential. While most structure-activity relationship campaigns have largely focused on lateral chain modifications and substituents on the BTZ core, scaffold hopping strategies have been rarely investigated previously. In this work, we report the first example of ring expansion of the BTZ core toward benzofuran- and naphthalene-fused thiazinones. In vitro testing showed micromolar activity for both compounds, and molecular docking simulations provided insights into their reduced inhibitory capacity toward the enzymatic target (DprE1). Calculated electrochemical potentials revealed a lower susceptibility to reduction as opposed to BTZ drug candidates, in line with the mechanistic requirement for covalent binding.

Unveiling the Pharmacological Significance of Marine Streptomyces violaceusniger KS20: Isolation, Characterization, and Assessment of Its Biomedical Applications.

Marine actinomycetes represent a highly favorable source of bioactive compounds and have been the mainstay of much research in recent years. Recent reports have shown that marine Streptomyces sp. can produce compounds with diverse and potent biological activities. Therefore, the key objective of the study was to isolate and screen a potential actinomycete from marine ecosystems of Devbagh and Tilmati beaches, Karwar. Streptomyces sp. KS20 was characterized and the ethyl acetate extract (EtOAc-Ex) was screened for biomedical applications. Streptomyces sp. KS20 produced grayish-white aerial and pale-yellow substrate mycelia and revealed an ancestral relationship with Streptomyces violaceusniger. Optimum growth of the organism was recorded at 30 °C and pH 7.0. The metabolite profiling of EtOAc-Ex expressed the existence of several bioactive metabolites, whereas the functional groups were indicated by Fourier transform infrared (FTIR) spectroscopy. A considerable antioxidant activity was shown for EtOAc-Ex with IC50 of 92.56 µg/mL. In addition to this, Streptomyces sp. KS20 exhibited significant antimicrobial properties, particularly against Escherichia coli, where a zone of inhibition measuring 36 ± 0.83 mm and a minimum inhibitory concentration (MIC) of 3.12 µg/mL were observed. The EtOAc-Ex even revealed significant antimycobacterial potency with IC50 of 6.25 µg/mL. Finally, the antiproliferative potentiality of EtOAc-Ex against A549 and PC-3 cell lines revealed a constant decline in cell viability while raising the concentration of EtOAc-Ex from 12.5 to 200 µg/mL. The IC50 values were determined as 94.73 µg/mL and 121.12 µg/mL for A549 and PC-3 cell lines, respectively. Overall, the exploration of secondary metabolites from marine Streptomyces sp. KS20 represents an exciting area of further research with the potential to discover novel bioactive compounds that could be developed into therapeutics for various medical applications.