Purification, characterization, and anticancer and antioxidant activities of L-glutaminase from Aspergillus versicolor Faesay4

Molecular expression, purification and structural characterization of recombinant L-Glutaminase from Streptomyces roseolus

The present research reports the anti-cancer potential of recombinant L-Glutaminase from Streptomyces roseolus. L-Glutaminase gene was synthesized by codon-optimization, cloned and successfully expressed in E. coli BL21 (DE3). Affinity purified recombinant L-Glutaminase revealed a molecular mass of 32 kDa. Purified recombinant L-Glutaminase revealed stability at pH 7.0-8.0 with optimum activity at 70 °C further indicating its thermostable nature based on thermodynamic characterization. Recombinant L-Glutaminase exhibited profound stability in the presence of several biochemical parameters and demonstrated its metalloenzyme nature and was also found to be highly specific towards favorable substrate (l-Glutamine) based on kinetics. It demonstrated antioxidant property and pronounced cytotoxic effect against breast cancer (MCF-7 cell lines) in a dose dependent behavior with IC50 of 40.68 μg/mL. Matrix-assisted laser desorption ionization-time of flight-mass spectroscopy (MALDI-TOF-MS) analysis of desired mass peaks ascertained the recombinant L-Glutaminase identity. N-terminal amino acid sequence characterization through Edman degradation revealed highest resemblance for L-glutaminase within the Streptomyces sp. family. The purified protein was characterized structurally and functionally by employing spectroscopic methods like Raman, circular dichroism and nuclear magnetic resonance. The thermostability was assessed by thermogravimetric analysis. The outcomes of the study, suggests the promising application of recombinant L-Glutaminase as targeted therapeutic candidate for breast cancer.

Evaluation of resistance patterns and bioremoval efficiency of hydrocarbons and heavy metals by the mycobiome of petroleum refining wastewater in Jazan with assessment of molecular typing and cytotoxicity of Scedosporium apiospermum JAZ-20

Jazan Industrial Economic City (JIEC) is located on the Red Sea coast in the province of Jazan, southwest of Saudi Arabia anchors diverse heavy and secondary industries in the energy, water desalination, petroleum, aluminum, copper, refineries, pharmaceuticals and food manufacturing fields. These various industries generate a large quantity of industrial wastewaters containing various toxicants. The present work represents ecologically beneficial alternatives for the advancement of environmental biotechnology, which could help mitigate the adverse impacts of environmental pollution resulting from petroleum refining effluents. The mycobiome (32 fungal strains) isolated from the industrial wastewater of the refinery sector in Jazan were belonged to five fungal genera including Fusarium, Verticillium, Purpureocillium, Clavispora and Scedosporium with a distribution percentage of 31.25, 21.88, 15.63, 12.50 and 18.75 %, respectively. These isolates showed multimetals tolerance and bioremoval efficiency against a large number of heavy metals (Fe2+, Ni2+, Cr6+, Zn2+, As3+, Cu2+, Cd2+, Pb2+, Ag+ and Hg2+) along with potent bioremediation activity toward crude oil and the polycyclic aromatic hydrocarbons. Interestingly, the mycobiome resistance patterns obtained against different classes of fungal antibiotics including azole (fluconazole, itraconazole, voriconazole, posaconazole, isavuconazole and ketoconazole), echinocandin (anidulafungin, caspofungin and micafungin) and polyene (amphotericin B) drugs proved the prevalence of antibiotic resistance among the mycobiome of refinery industry in Saudi Arabia is relatively low. The fungal isolate under isolation code JAZ-20 showed the highest bioremoval efficiency against heavy metals (90.8-100.0 %), crude oil (89.50 %), naphthalene (96.7 %), phenanthrene (92.52 %), fluoranthene (100.0 %), anthracene (90.34 %), pyrene (85.60 %) and chrysene (83.4 %). It showed the highest bioremoval capacity ranging from 85.72 % to 100.0 % against numerous pollutants found in a wide array of industrial effluents, including diclofenac, ibuprofen, carbamazepine, acetaminophen, sulfamethoxazole, bisphenol, bleomycin, vincristine, dicofol, methyl parathion, atrazine, diuron, dieldrin, chlorpyrifos, profenofos and phenanthrene. The isolate JAZ-20 was chosen for molecular typing, cytotoxicity assessment, analysis of volatile compounds and optimization investigations. Based on phenotypic, biochemical and phylogenetic analysis, strain JAZ-20 identified as Scedosporium apiospermum JAZ-20. This strain is newly discovered in industrial effluents in Saudi Arabia. Fungal strain JAZ-20 consistently produced various types of saturated and unsaturated fatty acids. the main fatty acids were C14:0 (1.95 %), iso-C14:0 (2.98 %), anteiso-C14:0 (2.13 %), iso-C15:0 (9.16 %), anteiso-C15:0 (11.75 %), C15:0 (7.42 %), C15:1 (2.37 %), anteiso-C16:0 (3.4 %), C16:0 (10.3 %), iso-C16:0 (9.5 %), C17:1 (1.36 %), anteiso-C17:1 (8.64 %), iso-C18:0 (11.0 %), C18:0 (3.63 %), anteiso-C19:0 (3.78 %), anteiso-C20:0 (2.0 %), iso-C21:0 (2.44 %), C23:0 (1.15 %), and C24:0 (2.17 %). These fatty acids serve as natural and eco-friendly antifungal agents, promoting fungal resistance and inhibiting the production of mycotoxins in the environment. Despite being an environmental isolate, its cytotoxicity was assessed against both normal and cancerous human cell lines. The IC50 values of JAZ-20 extract were 8.92, 10.41, 20.0, 16.5, and 40.0 μg/mL against WI38, MRC5, MCF10A, HEK293 and HDFs normal cells and 43.26, 33.75, and 40.0 μg/mL against liver (HepG2), breast (A549) and cervix (HeLa) cancers, respectively. Based on gas chromatography-mass spectrometry (GC-MS), analysis the extract of S. apiospermum JAZ-20 showed 47 known volatile compounds (VOCs) for varied and significant biological activities. Enhancing the bioremoval efficiency of heavy metals from actual refining wastewater involves optimizing process parameters. The parameters optimized were the contact time, the fungal biomass dosage, pH, temperature and agitation rate.

Proteases, a powerful biochemical tool in the service of medicine, clinical and pharmaceutical

Proteases, enzymes that hydrolyze peptide bonds, have various applications in medicine, clinical applications, and pharmaceutical development. They are used in cancer treatment, wound debridement, contact lens cleaning, prion degradation, biofilm removal, and fibrinolytic agents. Proteases are also crucial in cardiovascular disease treatment, emphasizing the need for safe, affordable, and effective fibrinolytic drugs. Proteolytic enzymes and protease biosensors are increasingly used in diagnostic and therapeutic applications. Advanced technologies, such as nanomaterials-based sensors, are being developed to enhance the sensitivity, specificity, and versatility of protease biosensors. These biosensors are becoming effective tools for disease detection due to their precision and rapidity. They can detect extracellular and intracellular proteases, as well as fluorescence-based methods for real-time and label-free detection of virus-related proteases. The active utilization of proteolytic enzymatic biosensors is expected to expand significantly in biomedical research, in-vitro model systems, and drug development. We focused on journal articles and books published in English between 1982 and 2024 for this study.

Application of statistical methodology for the optimization of L-glutaminase enzyme production from Streptomyces pseudogriseolus ZHG20 under solid-state fermentation

BACKGROUND

Actinomycetes are excellent microbial sources for various chemical structures like enzymes, most of which are used in pharmaceutical and industrial products. Actinomycetes are preferred sources of enzymes due to their high ability to produce extracellular enzymes. L-glutaminase has proven its essential role as a pharmaceutical agent in cancer therapy and an economic agent in the food industry. The current study aimed to screen the potent L-glutaminase producer and optimize the production media for maximum enzyme yield using one factor at a time (OFAT) approach and statistical approaches under solid-state fermentation (SSF).

RESULTS

Out of 20 actinomycetes strains isolated from rhizosphere soil, 5 isolates produced extracellular L-glutaminase. One isolate was chosen as the most potent strain, and identified as Streptomyces pseudogriseolus ZHG20 based on 16S rRNA. The production and optimization process were carried out under SSF, after optimization using OFAT method, the enzyme production increased up to 884.61 U/gds. Further, statistical strategy, response surface methodology (RSM), and central composite design (CCD) were employed for the level optimization of significant media component (p < 0.05), i.e., wheat bran, sesame oil cake, and corn steep liquor which are leading to increase 3.21-fold L-glutaminase production as compared to unoptimized media.

CONCLUSIONS

The presented investigation reveals the optimization of various physicochemical parameters using OFAT and RSM-CCD. Statistical approaches proved to be an effective method for increasing the yield of extracellular L-glutaminase from S. pseudogriseolus ZHG20 where L-glutaminase activity increased up to 1297.87 U/gds which is 3.21-fold higher than the unoptimized medium using a mixture of two solid substrates (wheat bran and sesame oil cake) incubated at pH 7.0 for 6 days at 33 °C.

Optimization of L-glutaminase production by Monascus ruber URM 8542 isolated from ice cream industrial effluent

L-glutaminase is a hydrolytic enzyme with wide biotechnological applications. Mostly, these enzymes are employed in the feed industry for flavor enhancement and acrylamide mitigation. Also, L-glutaminase may have antiviral and antineoplastic effects making it a good choice for pharmaceutical applications. In this study, the strain Monascus ruber URM 8542 was identified through classical and molecular taxonomy using partial sequencing of β-tubulin and calmodulin genes. Subsequently, the optimal culture conditions were evaluated by submerged fermentation (L-glutamine 10 g.L- 1) for L-glutaminase excretion. The isolate was identified as M. ruber URM 8542 which showed significant extracellular enzyme production with a yield of 11.4 times in relation to the specific activity of intracellular L-glutaminase. Regarding the optimization experiments, several factors such as L-glutamine concentration, temperature, and pH were compared using a full factorial design (23). The concentrations greater than 1% proved to be significantly better for glutaminase production (R2 = 0.9077). Additionally, the L-glutaminase was optimally active at pH 7.0 and 30 ºC. The L-glutaminase was remarkably stable across an alkaline pH range (7.0-8.0) and had a thermal stability ranging from 30 ºC to 60 ºC for 1 h. Taken together, these findings suggest that the L-glutaminase produced by M. ruber is a promising candidate for pharmacological application, although further studies need to be performed. To the best of our knowledge, this is the first report of L-glutaminase production by Monascus ruber.

Effect of Culture Conditions of Lophocereus marginatus Endophytic Fungi on Yield and Anticancer and Antioxidant Activities

Culture conditions affect the production of secondary metabolites in endophytic fungi. Therefore, the aim of the present study was to evaluate the yield and anticancer and antioxidant activity of endophytic fungi extracts from the cactus Lophocereus marginatus, under different culture conditions. The strains Penicillium citrinum, Aspergillus versicolor, Metarhizium anisopliae, and Cladosporium sp. were fermented in different culture media (potato dextrose agar, Czapeck broth, and malt broth), types of inoculums (spore or mycelium), and shaking conditions (150 rpm or static) for one week. Methanol extracts were obtained from mycelia, which was followed by determining their yields and evaluating their effect on L5178Y-R murine lymphoma cells growth and human peripheral blood mononuclear cells (PBMCs) viability, using the 3-[4,5dimethylthiazol-2-yl]2,5-diphenyl tetrazolium bromide reduction colorimetric assay. In addition, antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl test. We determined the half-maximal inhibitory concentration (IC₅₀) values of tumor cell growth inhibition, the selectivity index (SI), and the antioxidant activity, as compared with the healthy cells control. The best yields were obtained with the Czapeck broth medium in all the evaluated strains, reaching values of 50.3%. Of the 48 extracts evaluated, only seven significantly (p < 0.01) inhibited tumor cell growth (IC₅₀ < 250 µg/mL). A. versicolor extract showed the highest anticancer activity, after culturing spores (IC₅₀ = 49.62 µg/mL; SI = 15.8) or mycelium (IC₅₀ = 69.67 µg/mL; SI = 12.2) in malt broth, under static conditions. Extracts did not present significant antioxidant activity. In conclusion, we showed that culture conditions influenced the anticancer activity of L. marginatus endophytic fungi.

Analysis of Aspergillus versicolor exudate composition

Aspergillus versicolor, a widely distributed fungus, is associated with pollution and carcinogenic hazards. This study aimed to examine the functions of the A. versicolor exudate and laid a scientific foundation for improving our understanding, utilization, and control of A. versicolor. The A. versicolor exudate proteome, ion content, and amino acid components were determined using label-free quantitation, atomic absorption spectrophotometry, and high-performance liquid chromatography, respectively. In total, 502 proteins were identified in the A. versicolor exudate. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and cluster of orthologous group analyses were used to annotate the functional classification and pathways of the aligned proteins. Proteins identified in the exudate were mainly enriched in carbohydrate metabolic process, translation, oxidoreductase activity, oxidoreductase activity, hydrolase activity, cell wall-related processes, catalytic activity, and unknown functions. The exudate comprised Na, K, Ca, Fe, and Mg cations. Among the 17 types of amino acids detected in the exudate, 7 were essential and 10 were nonessential. The exudate may be involved in the vital processes of A. versicolor. Additionally, the exudate may play an important role in the growth, development, reproduction, homeostasis, nutrient supply for regrowth, and virulence of A. versicolor.

Recombinant production and characterization of L-glutaminase (glsA) as a promiscuity therapeutic enzyme

Because of the therapeutical impacts of hydrolytic enzymes in different diseases, in particular malignancies, we aimed to produce a recombinant putative L-glutaminase (GLS A_SL-1) from a recently characterized halo-thermotolerant Bacillus sp. SL-1. For this purpose, the glsA gene was identified and efficiently overexpressed in the Origami™ B (DE3) strain. The yield of the purified GLS A_SL-1 was ~ 20 mg/L, indicating a significant expression of recombinant enzyme in the Origami. The enzyme activity assay revealed a significant hydrolytic effect of the recombinant GLS A_SL-1 on L-asparagine (Asn) (i.e., K_m 39.8 μM, k_cat 19.9 S^-1) with a minimal affinity for L-glutamine (Gln). The GLS A_SL-1 significantly suppressed the growth of leukemic Jurkat cells through apoptosis induction (47.5%) in the IC₅₀ dosage of the enzyme. The GLS A_SL-1 could also change the Bax/Bcl2 expression ratio, indicating its apoptotic effect on cancer cells. The in silico analysis was conducted to predict structural features related to the histidine-tag exposure in the N- or C-terminal of the recombinant GLS A_SL-1. In addition, molecular docking simulation for substrate specificity revealed a greater binding affinity of Asn to the enzyme binding-site residues than Gln, which was confirmed in experimental procedures as well. In conclusion, the current study introduced a recombinant GLS A_SL-1 with unique functional and structural features, highlighting its potential pharmaceutical and medical importance. GLS A_SL-1 represents the first annotated enzyme from Bacillus with prominent asparaginase activity, which can be considered for developing alternative enzymes in therapeutic applications. KEY POINTS: • Hydrolytic enzymes have critical applications in different types of human malignancies. • A recombinant L-glutaminase (GLS A_SL-1) was produced from halo-thermotolerant Bacillus sp. SL-1. • GLS A_SL-1 displayed a marked hydrolytic activity on L-asparagine compared to the L-glutamine. • GLS A_SL-1 with significant substrate promiscuity may be an alternative for developing novel pharmaceuticals.

Fungal Proteases as Emerging Biocatalysts to Meet the Current Challenges and Recent Developments in Biomedical Therapies: An Updated Review

With the increasing world population, demand for industrialization has also increased to fulfill humans' living standards. Fungi are considered a source of essential constituents to produce the biocatalytic enzymes, including amylases, proteases, lipases, and cellulases that contain broad-spectrum industrial and emerging applications. The present review discussed the origin, nature, mechanism of action, emerging aspects of genetic engineering for designing novel proteases, genome editing of fungal strains through CRISPR technology, present challenges and future recommendations of fungal proteases. The emerging evidence revealed that fungal proteases show a protective role to many environmental exposures and discovered that an imbalance of protease inhibitors and proteases in the epithelial barriers leads to the protection of chronic eosinophilic airway inflammation. Moreover, mitoproteases recently were found to execute intense proteolytic processes that are crucial for mitochondrial integrity and homeostasis function, including mitochondrial biogenesis, protein synthesis, and apoptosis. The emerging evidence revealed that CRISPR/Cas9 technology had been successfully developed in various filamentous fungi and higher fungi for editing of specific genes. In addition to medical importance, fungal proteases are extensively used in different industries such as foods to prepare butter, fruits, juices, and cheese, and to increase their shelf life. It is concluded that hydrolysis of proteins in industries is one of the most significant applications of fungal enzymes that led to massive usage of proteomics.

Assessment of the phylogenetic analysis and antimicrobial, antiviral, and anticancer activities of marine endophytic Streptomyces species of the soft coral Sarcophyton convolutum

In the present work, the extensive biological activities of marine endophytic Streptomyces strains isolated from marine soft coral Sarcophyton convolutum have been demonstrated. Within fifty-one Streptomyces isolates evaluated for their hydrolytic enzymes and enzyme inhibitors productivities, six isolates showed the hyperactivities. Pharmaceutical metabolites productivities evaluated include enzymes (alkaline protease, L-asparaginase, L-glutaminase, tyrosinase, and L-methioninase) and enzyme inhibitors (inhibitors of α-amylase, hyaluronidase, β-lactamase, α-glucosidase, and β-glucosidase). These isolates were identified based on their morphological, biochemical, and genetic characteristics as Streptomyces sp. MORSY 17, Streptomyces sp. MORSY 22, Streptomyces sp. MORSY 25, Streptomyces sp. MORSY 36, Streptomyces sp. MORSY 45, and Streptomyces sp. MORSY 50. Moreover, in further evaluation, these strains exhibited wide spectrum of antimicrobial (against bacteria and fungi), antiviral (against hepatitis C virus), antibiofilm against biofilm-forming bacteria (methicillin-resistant Staphylococcus aureus and multidrug-resistant Pseudomonas species), and anti-proliferative activities (against liver and colon carcinoma cell lines). The GC-MS analysis of the hyperactive strains MORSY 17 and MORSY 22 revealed the presence of different bioactive agents in the ethyl acetate extract of both strains.

Bio-prospecting the future in perspective of amidohydrolase L-glutaminase from marine habitats

In the current scenario, considerable attention is being given to the enzyme L-glutaminase (EC 3.5.1.2). It belongs to the amidohydrolase class adherent to the family of serine-reliant β-lactamases and the penicillin-binding proteins due to its higher affinity to polymerize and modify peptidoglycan synthesis. However, based on the catalytic proficiency, L-glutaminase is characterized as a proteolytic endopeptidase that cleaves peptide linkage and emancipates various byproducts, viz. ammonia along with glutamate. L-glutamine is considered the key amino acid reportedly involved in multiple metabolic pathways such as nitrogen metabolism. The present review is focused on the recent development and aspects concomitant to the biotechnological applicability of L-glutaminase predominantly from the marine habitat. Additionally, a majority of L-glutaminases finds application in cancer therapy as therapeutic agents, especially for acute lymphocytic leukaemia. The in vitro studies have been effective against various human cancer cell lines. L-glutaminase enhances the growth of probiotic bacteria. Apart from all these applications, it is suitably applicable in fermented foods as a flavour enhancer especially the umami flavour and content. Marine habitats have largely been exploited for their bio-catalytic potential but very scarcely for therapeutic enzymes. Some of the reports of such marine bacterial isolates from Bacillus sp., Pseudomonas sp. and Vibrio sp. are in the domain, but none highlights the therapeutic applications predominantly as anticancer and anti-proliferative agents. KEY POINTS: The exploration of marine habitats along the Gujarat coasts mainly for bacteria secreting L-glutaminase is scarcely reported, and even more scarce are the amidohydrolases from these marine niches as compared to their terrestrial counterparts. Microbial sourced amidohydrolase has wide bio-applicability that includes food, cosmetics and therapeutics especially as anticancer/anti-proliferative agent making it of immense biotechnological significance.