Iranian Research Organization for Science and Technology (IROST) Microbiology, Metabolites and Biotechnology 2980-8855 6 2 2023 11 01 Optimization of L-asparaginase type II produced by Bacillus velezensis SE114 1 16 1369 10.22104/mmb.2024.6548.1129 EN Fereshteh Hozoorbakhsh Department of Microbiology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran Mozhgan Ghiasian Department of Microbiology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran Fereshte Ghandehari Department of Microbiology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran Zarrindokht Emami-Karvani Department of Microbiology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran Maryam Khademi Dehkordi Department of Biology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran Journal Article 2023 10 29 Once the acute lymphoblastic leukemia cells that need L-asparagine are exposed to L-ASNase, they die because of the limitations of L-asparagine. The globally rising rate of ALL also requires extraordinary efforts to discover new microorganisms with high L-ASNase production and efficiency. The aim of this study is the high amount of L-ASNase production. After isolation, the L-ASNase production was optimized using the response surface methodology and the central composite design. Then, in-silico studies were predicted for the L-ASNase-producing gene. In this study, Bacillus velezensis was isolated as an L-ASNase producer from slaughterhouse effluent using the M9 medium. The optimization process further illustrated Tween 20, glucose, temperature, and L-asparagine, which were more significant for L-ASNase production. Based on statistical prediction by response surface methodology, more enzyme activity (7.11 U/mL) could be realized at 0.6% Tween 20, 1.7% glucose, 55°C temperature, and 1.8% L-asparagine. The in-silico studies also established that the binding site is located at the N-terminal domain and the active site flexible loop. Additionally, it contained Thr36, Ala47, Tyr50, Glu84, Asp117, Thr116, Met142, Lys189, Thr193, and Thr192 as the conserved and functional residues in L-ASNase. It was concluded that B. velezensis SE114 produced L-ASNase type II in the present study. The statistical optimization results also showed that Tween 20, glucose, temperature, and L-asparagine were significant variables affecting the L-ASNase production. In addition, temperature and L-asparagine had noteworthy interactions.

https://mmb.irost.ir/article_1369_4e26d78e6e7126999a058e290fd8f62c.pdf

Iranian Research Organization for Science and Technology (IROST) Microbiology, Metabolites and Biotechnology 2980-8855 6 2 2023 11 01 The Efficacy of Stabilizers on Lactoperoxidase System’s Antibacterial Activity and Stability: A Review 17 36 1351 10.22104/mmb.2024.6569.1130 EN Marziyeh Borjian Boroujeni Department of Biology, Faculty of Sciences, University of Guilan, Rasht, Iran. Mahmoud Reza Aghamaali Department of Biology, Faculty of Sciences, University of Guilan, Rasht, Iran. Hashem Naieri Department of Biochemistry, Falavarjan Branch, Islamic Azad University, Isfahan, Iran Keivan Beheshti-Maal Department of Microbiology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran. Journal Article 2023 10 29 The lactoperoxidase System holds significant prominence as a pivotal protein within milk, assuming a defensive role in combating diverse strains of microorganisms, particularly those with deleterious implications for milk quality. The stabilization process of the lactoperoxidase enzyme offers numerous advantages and benefits within an academic context and allows for controlled modulation of the enzyme's effects. Stabilized enzymes have attracted considerable research attention due to their favorable attributes, including easy separation from reaction mixtures, and the potential for reusing enzymes from multiple sources, to find and improve valuable methodologies. This review summarized the role of stabilizers in enhancing the efficacy and stability of the lactoperoxidase system and antibacterial applications in cosmetics, pharmaceutical, food, and health industries. This enzyme possesses characteristics that make it an effective natural antibacterial agent, leading to the extension of the lifespan and improvement of the stability of diverse types of dairy products and milk. It is used especially in remote areas where farmers are not close to the market. The common findings confirmed the ability of stabilizers to enhance enzyme stability in unfavorable environmental conditions that result in the extension of the activity period of the enzyme. Therefore, this characteristic indirectly enhances the enzyme's remarkable effectiveness against bacteria. Finally, according to various studies, the main function of stabilizing agents is the enhancement of enzyme stability as well as the longevity of the enzyme. Overall, it seems the stabilizers have a supplementary function in improving the enzyme's ability to kill bacteria through increased enzymatic activity.

https://mmb.irost.ir/article_1351_172b526f5940b0da5ed5d2899e3cee11.pdf

Iranian Research Organization for Science and Technology (IROST) Microbiology, Metabolites and Biotechnology 2980-8855 6 2 2023 11 01 Frequency of Listeria monocytogenes and Brucella abortus Infections in the Vaginal Secretions of Women with Spontaneous Abortion: A case study 37 45 1383 10.22104/mmb.2024.6602.1131 EN Atefeh Bayat Depatment of Microbiology, Falavarjan Branch, Islamic Azad University, Falavarjan, Isfahan, Iran Ali Mohammad Ahadi Department of Genetics, Shahrekord University, Shahrekord, Iran Monir Doudi Depatment of Microbiology, Falavarjan Branch, Islamic Azad University, Falavarjan, Isfahan, Iran Hatav Ghasemi Tehrani Department of Obstetrics and Gynecology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran Journal Article 2023 11 18 Abortion is an involuntary and spontaneous termination of pregnancy. Various factors can be involved in abortion, and many of them are currently unknown. Among these, bacterial infections are of particular importance. This study aimed to investigate the presence of Listeria monocytogenes and Brucella abortus in the vaginal secretions of women suffering from abortion by biochemical and molecular methods. In the present study, a total of 110 samples of vaginal secretions from women suffering from abortion were collected in 2019 in Isfahan, Iran. The samples were collected from patients referred to gynecologists, obstetricians, and infertility specialists. Then, an antibiotic sensitivity test for bacterial isolates was done using the standard antibiogram method. The molecular detection of bacteria was performed by PCR reaction using specific primers designed for 16S rRNA gene amplification of L.monocytogenes and B. abortus. Based on the results, a total of 110 isolates of bacteria were obtained in the present study from women with and without abortion (control). Among the isolates, three belonged to L. monocytogenes (10.3%), and one belonged to B. abortus (3.4%). B. abortus was sensitive to all antibiotics used, and only one of the three L. monocytogenes isolates was resistant to tetracycline, ampicillin, and gentamicin antibiotics. The results of molecular identification showed that designing a species-specific primer to amplify the 16S rRNA gene by PCR assay may be a fast, low-cost, and reliable tool for screening for bacterial agents involved in abortion, which needs more study in the population. The high prevalence of L. monocytogenes in the vaginal secretions of women suffering from abortion is cause for concern and should be taken into consideration by treatment staff.

https://mmb.irost.ir/article_1383_0c78f51a40d322f189d7874024b62ee6.pdf

Iranian Research Organization for Science and Technology (IROST) Microbiology, Metabolites and Biotechnology 2980-8855 6 2 2023 11 01 The effects of culture media and various NAA, sucrose and mesos concentrations on in vitro propagation of Gerbera jamesonii 46 52 1334 10.22104/mmb.2023.6434.1119 EN Morteza Fayeghi Mohammadi Department of Horticulture Sciences, College of Agriculture and Natural Resources, University of Mohagheh Ardabili, Iran Mousa Torabi Department of Horticulture Sciences, College of Agriculture and Natural Resources, University of Mohagheh Ardabili, Iran Batool Hosseinpour Department of Agriculture, Iranian Research Organization for Science and Technology, Tehran, Iran Journal Article 2023 08 16 Gerbera jamesonii Bolus is one of the most popular ornamental plants worldwide and its micrpropgation allows to produce a large number of true to type plants with good quality in a short time. In vitro propagation of gerbera requires culture media supplemented with specific concentrations of minerals, organic supplements and energy sources. The aim of this study was to determine suitable culture medium and evaluate different concentrations of sucrose and Naphtalic Acetic Acid (NAA) for in vitro development of gerbera explants. Micro shoots of two gerbera cultivars (Artist and Brilliance) were cultured on four different culture media and the effect of various concentrations of sucrose (20 and 30 g L-1) as well as MgSO4.7H2O and CaCl2.2H2O (0.5X, 1X and 1.5X) on in vitro propagation properties were examined. MS medium provided better shoot development and application of lower concentration of sucrose improved the efficiency of gerbera micropropagation. In Artist cultivar, the highest number of shoots was obtained by using 20 g L-1 of sucrose and with or without NAA application (9.08 micro shoots per explant). In contrast, Brilliance produced the highest number of shoots by using 20 g L-1 of sucrose and 0.1 mg L-1 of NAA (7.4 micro shoots per explant). In addition, the increase or decrease of MgSO4.7H2O and CaCl2.2H2O did not change propagation efficiency. The results can contribute to optimize bioreactor systems for large-scale production.

https://mmb.irost.ir/article_1334_05377e493ffc21d9a613049a02321eca.pdf

Iranian Research Organization for Science and Technology (IROST) Microbiology, Metabolites and Biotechnology 2980-8855 6 2 2023 11 01 Comparison of Antibiotic Susceptibility of Klebsiella Species Causing Urinary Tract Infection in Iran and Other Countries around Asia 53 62 1399 10.22104/mmb.2024.6840.1139 EN Moeen Hamidi Hesari Islamic Azad University of Nishapur, Department of Biology, Nishapur, Iran Imam Khomeini Hospital, Shirvan, North Khorasan University of Medical Sciences, Bojnurd, Iran Taban Hashemi Islamic Azad University of Nishapur, Department of Biology, Nishapur, Iran Jafar Hemmat Biotechnology Department, Iranian Research Organization for Science and Technology, IROST , Tehran, Iran Norkhoda Sadeghi Fard Medical University of Ilam, Clinical Microbiology Research Center, Ilam, Iran Journal Article 2024 03 21 This study aimed to evaluate the antibiotic-susceptibility pattern of Klebsiella pneumoniae causing urinary tract infection (UTI) in two geographical regions of Iran and then compare it to the rest of Iran and other countries. Over a year, from winter 2014 to winter 2015, 80 cases of Klebsiella were isolated from 2584 urine samples and identified using biochemical and microbiological tests. The disk diffusion method was used to determine antibiotic susceptibility based on the standard protocols provided by the CLSIs. The results of this study were compared with several reports from Iran and other countries, before the COVID-19 pandemic from 2007 to 2018. Based on the results of the antibiotic susceptibility of 80 isolated K. pneumoniae, amikacin (AN), Meropenem (MEN), gentamicin (GM), and ciprofloxacin (CP) were identified as the most sensitive antibiotics with 77.5%, 77%, 75%, and 58.75% sensitivity, respectively. A comparison of 17 report results showed imipenem (IPM) is the most sensitive antibiotic against the K. pneumoniae isolates, with a sensitivity range of 85% -100%. Followed by amikacin (AN), which was reported as the first or second antibiotic or third or fourth antibiotic in less than 30% of the cases. CP was reported as a second or third option in 22% of the cases. This study evaluated the sensitivity pattern of K. pneumoniae to antibiotics, and the results show that it has the potential to be applied to further studies and related programs, including periodic screening, regional screening, and revision in therapeutic approaches.

https://mmb.irost.ir/article_1399_152ff6a302aa13bf8d452b35bb391c4e.pdf

Iranian Research Organization for Science and Technology (IROST) Microbiology, Metabolites and Biotechnology 2980-8855 6 2 2023 11 01 Enhancing keratinase production of a native Bacillus paralicheniformis FUM-2 through random mutagenesis using a chemical agent and ultraviolet 63 72 1428 10.22104/mmb.2024.6337.1113 EN Sahar Mehraban Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran Masoumeh Bahreini Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran Ahmad Assodeh Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran Mohammad Reza Sharifmoghadam Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran Journal Article 2023 08 09 Daily accumulation of feather waste due to the development of the poultry industry is a critical issue, considering the environmental and health hazards. Among feather waste disposal methods, biodegradation is a practical, cheap, and environment-friendly method. This study aimed to enhance the keratinolytic activity of FUM-2 isolate, a native keratinolytic bacterium, using mutations and culture improvement. The isolate was identified as Bacillus paralicheniformis based on biochemical, morphological, and molecular analysis. Using the one factor at a time (OFAT) method, the isolate produced more keratinase at 45 °C, pH 11, 2% carbon substrate concentration, 75% aeration rate, and 48 hours incubation. Also, it was able to degrade both α and β keratin. Culture improvement increased enzyme production from 507.6 U/mL to 1706.4 U/mL. In random mutation using ultraviolet radiation, three mutants were isolated, and a 10-minute UV-treated mutant of UVF2-D showed a 36.3% increase in keratinolytic activity compared to its parent. In the next round of mutagenesis by ethidium bromide, seven double mutants were isolated from the UVF2-D mutant, among which the EUF2-D2 double mutant showed a 79% increase in keratinolytic activity. No viable mutants were isolated from the wild strain using ethidium bromide. Our results show that many organisms can potentially produce beneficial products that could be improved using random mutagenesis and optimization methods, which are more useful for strain improvement than complex and costly molecular techniques.

https://mmb.irost.ir/article_1428_f7b2c4a0e1f219e834307a2e7e0f5eb9.pdf