Identification Of Bacterial Strains Research Articles

The Challenge of Bacterial Strain Identification: Leptospira interrogans Serovars Australis in a Dog and Long-Term Clinical Follow-Up

Leptospirosis is a widespread disease throughout the world, presenting in severe clinical forms in dogs. The pathogenicity of the different serovars in field infections is not fully documented, and clinical diagnosis is often limited to a combination of serological tests and molecular analyses. The latter, although a fundamental tool, cannot identify the infecting strain without further analysis. This study reports the use of various indirect (microscopic agglutination test, MAT) and direct (microbiological culture, real-time PCR) laboratory techniques, followed by typing protocols (Multi-locus Sequence Typing (MLST), Multiple Loci Variable number tandem repeat Analysis (MLVA), serotyping) that allowed for the identification of the Leptospira serovar Australis in a symptomatic and previously vaccinated dog (vaccine containing heterologous strains). This study reports long-term clinical follow-up (0–640 days) and describes the possible role of the infection in the development of chronic renal failure. This study aims to highlight how a combination of different techniques can be useful to better characterise the environmental circulation of zoonotic agents. Therefore, the identification and isolation of circulating L. strains would facilitate the updating of epidemiological data, enhance the knowledge of pathogenicity and long-term clinical effects, and provide a valuable resource for improving the efficacy of a specific serovar vaccination.

The Influence of COVID-19 on Antimicrobial-Resistance in Gram-Positive Bacteria at a Private Saudi Hospital: A Five-Year Evaluation

Due to the emergence of antimicrobial-resistance (AR) as a public health threat, the Saudi National Action Plan (SNAP) was implemented in 2017, incorporating various strategies to combat AR. To evaluate the effectiveness of SNAP and the impact of COVID-19, the study analyzed pre- and post-pandemic rates of AR, methicillin-resistant Staphylococcus aureus (MRSA), and multidrug resistance (MDR) among Gram-positive bacteria at a private medical center in Saudi Arabia. This study reviewed the cases of all patients who had been diagnosed with Gram-positive bacterial infection between January 2017 and December 2021. Bacterial strain identification was conducted using VITEK-2 ID-GP cards, while AR, MRSA, and MDR were defined using AST-GP 67 and AST-ST02 cards, all adhering to the manufacturer’s recommended protocols. The five-year study from 2017 to 2021 yielded 6,271 Gram-positive bacteria isolates from patients in a Saudi private hospital. Though the rate of AR initially declined between 2017 and 2019, it spiked significantly from 2020 to 2021. Similarly, the MRSA rate exhibited a substantial decrease (p < 0.05) from 2017 to 2019, followed by a significant rise (p < 0.05) between 2020 and 2021. Out of the isolated pathogens, 1,031 (16.44%) exhibited MDR, with all isolates showing a marked increase (p < 0.05) in MDR from 2020 to 2021. The study highlights the aggravating impact of the COVID-19 pandemic on AR, underscoring the need for the SNAP to intensify its efforts in combating AR.

Deep Learning-enhanced Hyperspectral Imaging for the Rapid Identification and Classification of Foodborne Pathogens

Background: Bacterial cellulose (BC) is a versatile biomaterial with numerous applications, and the identification of bacterial strains that produce it is of great importance. This study explores the effectiveness of a Stacked Autoencoder (SAE)-based deep learning method for the classification of bacterial cellulose-producing bacteria. Objective: The primary objective of this research is to assess the potential of SAE-based classification models in accurately identifying and classifying bacterial cellulose-producing bacteria, with a particular focus on strain GZ-01. Methods: Strain GZ-01 was isolated and subjected to a comprehensive characterization process, including morphological observations, physiological and biochemical analysis, and 16S rDNA sequencing. These methods were employed to determine the identity of strain GZ-01, ultimately recognized as Acetobacter Okinawa. The study compares the performance of SAE-based classification models to traditional methods like Principal Component Analysis (PCA). Results: The SAE-based classifier exhibits outstanding performance, achieving an impressive accuracy of 94.9% in the recognition and classification of bacterial cellulose-producing bacteria. This approach surpasses the efficacy of conventional PCA in handling the complexities of this classification task. Conclusion: The findings from this research highlight the immense potential of utilizing nanotechnology- driven data analysis methods, such as Stacked Autoencoders, in the realm of bacterial cellulose research. These advanced techniques offer a promising avenue for enhancing the efficiency and accuracy of bacterial cellulose-producing bacteria classification, which has significant implications for various applications in biotechnology and materials science.

Discrimination of Common E. coli Strains in Urine by Liquid Chromatography-Ion Mobility-Tandem Mass Spectrometry and Machine Learning.

Accurate identification of bacterial strains in clinical samples is essential to provide an appropriate antibiotherapy to the patient and reduce the prescription of broad-spectrum antimicrobials, leading to antibiotic resistance. In this study, we utilized the combination of a multidimensional analytical technique, liquid chromatography-ion mobility-tandem mass spectrometry (LC-IM-MS/MS), and machine learning to accurately identify and distinguish 11 Escherichia coli (E. coli) strains in artificially contaminated urine samples. Machine learning was utilized on the LC-IM-MS/MS data of the inoculated urine samples to reveal lipid, metabolite, and peptide isomeric biomarkers for the identification of the bacteria strains. Tandem MS and LC separation proved effective in discriminating diagnostic isomers in the negative ion mode, while IM separation was more effective in resolving conformational biomarkers in the positive ion mode. Using hierarchical clustering, the strains are clustered accurately according to their group highlighting the uniqueness of the discriminating biomarkers to the class of each E. coli strain. These results show the great potential of using LC-IM-MS/MS and machine learning for targeted omics applications to diagnose infectious diseases in various environmental and clinical samples accurately.

Isolation and characterization of beneficial bacteria from <i>Apis Cerana</i> honeybees from Hanoi, Vietnam

Beneficial bacteria are vital for maintaining honeybee health by outcompeting pathogenic microorganisms, boosting immunity, and enhancing resilience to diseases. Identifying the specific bacterial strains associated with honeybees enables the development of targeted probiotics that can improve the health of bees and humans. The present study describes the isolation and identification of bacterial strains from Apis cerana honeybees in Hanoi, Vietnam, utilizing a culture-based method, Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry (MALDI-TOF) analysis, and 16S rRNA sequencing. MALDI-TOF analysis revealed several beneficial bacterial species, including Lactobacillus kunkeei, Lactobacillus plantarum, Pediococcus pentosaceus, Leuconostoc mesenteroides, Leuconostoc citreum, Bacillus subtilis, and Bacillus megaterium. Antimicrobial spectrum analysis showed that 16 out of the 23 identified isolates exhibited inhibitory effects against tested bacteria. Selected isolates with broad antimicrobial spectra, including L. kunkeei, L. plantarum, P. pentosaceus, L. mesenteroides, L. citreum, and B. subtilis, were further validated through 16S rRNA gene sequencing. The results confirmed the identity of these strains, emphasizing the probiotic potential of L. kunkeei, L. plantarum, L. mesenteroides, L. citreum, P. pentosaceus, and B. subtilis for honeybee health. Our findings provide valuable insights into the bacterial diversity and antimicrobial properties associated with honeybees, suggesting their use as probiotics in beekeeping and beyond.

Biodegradation of Mandelonitrile Using Bacillus sp.: A Potential Approach for Environmental Remediation

Mandelonitrile, a cyanogenic compound, poses environmental risks due to its toxicity and potential to release hydrogen cyanide. The potential technique for removing mandelonitrile from polluted environments is biodegradation. In this study, we investigated the isolation and identification of bacterial strains from soil samples for the biodegradation of mandelonitrile. The selective enrichment culture technique was used for isolation, using mandelonitrile as the sole carbon and nitrogen source. The isolated strain was identified and named Bacillus sp based on morphological studies and biochemical analysis. MN1. Further degradation studies demonstrated the efficiency of the isolated strain in degrading mandelonitrile under optimum conditions. Bacillus sp. MN1 can degrade 0.5% v/v mandelonitrile completely into mandelic acid and ammonia under optimum conditions of 30 °C and pH 7.5 within five days of incubation. The enzyme assay and HPLC analysis show that mandelonitrile degradation by Bacillus sp. MN1 follows the Nitralase pathway, mandelic acid, and ammonia. This research study reveals the potential application of Bacillus sp. in the bioremediation of mandelonitrile-contaminated sites, highlighting the importance of microbial biodegradation in environmental management strategies.

Characteristics of rhizobacteria in potential hyperaccumulator vegetation and their resistance to gold mine tailing stress

The use of local bacteria is preferred in bioleaching as an environmental-friendly alternative technology in gold mining. In a preliminary study, rhizobacteria were isolated and cultured from three types of hyperaccumulator vegetation from the Ratatotok gold mine, Indonesia, namely Pteris vittata L., Syzygium aromaticum L., and Swietenia mahagoni Jacq. These rhizobacteria still need to be characterised and identified. This study is aimed to cover bacterial phenotypic characterisation, assessment of bacteria resistance to tailing, and identification of bacterial strains the exhibit the highest resistance to tailings. The assessment was carried out across a spectrum of tailing concentrations, selecting the three most robust strains for molecular identification. The process involved genotypic characterisation to determine the species name by analysing the 16S rRNA gene. The results reveal that the phenotypic characteristics of the bacteria isolates vary, but all of them are the indole acetic acid (IAA) hormone producers. The highest IAA producer is the isolate from the rhizosphere of S. aromaticum. Based on the genotypic characterisation test, three most resistant isolates to tailing stress are the following strains Pseudomonas aeruginosa (RTKP1) and Stenotrophomonas geniculata (RTKP2), both from the rhizosphere of P. vittata; as well as Bacillus cereus (RTKS) from the rhizosphere of S. aromaticum. These three strains need to be further tested for their bioleaching capability to recover gold from tailings. Additionally, this study recommends that gold recovery using biological agents can combine the role of hyperaccumulator plants in phytomining and rhizobacteria in bioleaching.

In-silico analysis of probiotic attributes and safety assessment of probiotic strain Bacillus coagulans BCP92 for human application.

The whole genome sequence (WGS) of Bacillus coagulans BCP92 is reported along with its genomic analysis of probiotics and safety features. The identification of bacterial strain was carried out using the 16S rDNA sequencing method. Furthermore, gene-related probiotic features, safety assessment (by in vitro and in silico), and genome stability were also studied using the WGS analysis for the possible use of the bacterial strain as a probiotic. From the BLAST analysis, bacterial strain was identified as Bacillus (Heyndrickxia) coagulans. WGS analysis indicated that the genome consists of a 3 475 658bp and a GC-content of 46.35%. Genome mining of BCP92 revealed that the strain is consist of coding sequences for d-lactate dehydrogenase and l-lactate dehydrogenases, 36 genes involved in fermentation activities, 29 stress-responsive as well as many adhesions related genes. The genome, also possessing genes, is encoded for the synthesis of novel circular bacteriocin. Using an in-silico approach for the bacterial genome study, it was possible to determine that the Bacillus (Heyndrickxia) coagulans strain BCP92 contains genes that are encoded for the probiotic abilities and did not harbour genes that are risk associated, thus confirming the strain's safety and suitability as a probiotic to be used for human application.

Genome sequence-based identification of Enterobacter strains and description of Enterobacter pasteurii sp. nov.

Accurate taxonomy is essential for microbial biological resource centers, since the microbial resources are often used to support new discoveries and subsequent research. Here, we used genome sequence data, alongside matrix-assisted laser desorption/ionization time-of-flight mass spectrometer biotyper-based protein profiling, to accurately identify six Enterobacter cloacae complex strains. This approach effectively identified distinct species within the E. cloacae complex, including Enterobacter asburiae, "Enterobacter xiangfangensis," and Enterobacter quasihormaechei. Moreover, the study revealed the existence of a novel species within the Enterobacter genus, for which we proposed the name Enterobacter pasteurii sp. nov. In summary, this study demonstrates the significance of adopting a genome sequence-driven taxonomy approach for the precise identification of bacterial strains in a biological resource center and expands our understanding of the E. cloacae complex.

Plant-Disease-Suppressive and Growth-Promoting Activities of Endophytic and Rhizobacterial Isolates Associated with Citrullus colocynthis.

This study was conducted to investigate the antagonistic potential of endophytic and rhizospheric bacterial isolates obtained from Citrullus colocynthis in suppressing Fusarium solani and Pythium aphanidermatum and promoting the growth of cucumber. Molecular identification of bacterial strains associated with C. colocynthis confirmed that these strains belong to the Achromobacter, Pantoea, Pseudomonas, Rhizobium, Sphingobacterium, Bacillus, Sinorhizobium, Staphylococcus, Cupriavidus, and Exiguobacterium genera. A dual culture assay showed that nine of the bacterial strains exhibited antifungal activity, four of which were effective against both pathogens. Strains B27 (Pantoea dispersa) and B28 (Exiguobacterium indicum) caused the highest percentage of inhibition towards F. solani (48.5% and 48.1%, respectively). P. aphanidermatum growth was impeded by the B21 (Bacillus cereus, 44.7%) and B28 (Exiguobacterium indicum, 51.1%) strains. Scanning electron microscopy showed that the strains caused abnormality in phytopathogens' mycelia. All of the selected bacterial strains showed good IAA production (>500 ppm). A paper towel experiment demonstrated that these strains improved the seed germination, root/shoot growth, and vigor index of cucumber seedlings. Our findings suggest that the bacterial strains from C. colocynthis are suppressive to F. solani and P. aphanidermatum and can promote cucumber growth. This appears to be the first study to report the efficacy of these bacterial strains from C. colocynthis against F. solani and P. aphanidermatum.

Are the predicted known bacterial strains in a sample really present? A case study.

With mutations constantly accumulating in bacterial genomes, it is unclear whether the previously identified bacterial strains are really present in an extant sample. To address this question, we did a case study on the known strains of the bacterial species S. aureus and S. epidermis in 68 atopic dermatitis shotgun metagenomic samples. We evaluated the likelihood of the presence of all sixteen known strains predicted in the original study and by two popular tools in this study. We found that even with the same tool, only two known strains were predicted by the original study and this study. Moreover, none of the sixteen known strains was likely present in these 68 samples. Our study thus indicates the limitation of the known-strain-based studies, especially those on rapidly evolving bacterial species. It implies the unlikely presence of the previously identified known strains in a current environmental sample. It also called for de novo bacterial strain identification directly from shotgun metagenomic reads.

Improved and simplified method for aseptic isolation of nematodes and nematode-endosymbiotic bacteria from pine seedlings

Pine wilt disease (PWD), caused by the pinewood nematode (PWN), Bursaphelenchus xylophilus, significantly impacts pine species and poses a broader ecological concern. An understanding of these nematode-associated microbes is essential for formulating sustainable PWD management strategies. We introduce a streamlined method for the aseptic extraction of B. xylophilus from pine seedlings, evolving beyond traditional Baermann funnel approaches. The method ensures optimal nematode extraction under sterile parameters, with seedling cutting discs processed using a unique sterile syringe assembly setup. The efficiency and simplicity of this method promise to significantly reduce the time and resources required. It also incorporates endosymbiotic bacterial isolation from isolated nematodes. The robustness of this method is affirmed by the successful isolation and identification of nematodes and bacterial strains as endosymbionts. Collectively, this protocol paves the way for more effective studies of nematodes and associated microbes, promoting the understanding of PWD and offering practical implications for better PWD management.•A simplified, aseptic method for extracting B. xylophilus from pine seedlings, offering a modern alternative to traditional Baermann funnel method.•Utilization of a specialized sterile syringe assembly setup, ensuring controlled and optimal nematode isolation.•Method validation achieved through the successful isolation and identification of bacterial strains as nematode endosymbionts.

Plasmid and Cell Envelope Characterization of <i>Vibrio alginolyticus</i> Isolated from Infected Tiger Prawn,<i>Penaeus monodon</i>

It has been reported that indiscriminate use of antibacterial compounds in aquaculture has resulted in an increase in populations of antibiotic resistant strains of bacteria. In the present study, Vibrio alginolyticus isolated from infected Penaeus monodon has been found resistant to Furoxone (30 g), Ampicillin (10 g), Cloxacillin (1 g), Bacitracin (10 units), Penicillin (10 units) and Oxytetracycline (30 pg) by antibiotic sensitivity test, suggesting the restricted prophylactic use of antibiotics in shrimp aquaculture industry. As an approach towards differentiation and identification of bacterial strain, the plasmid characterization of V. alginolyticus by restriction enzyme analysis was carried out which revealed the presence of 6.3 kb and 0.8 kb DNA fragments by Hind lil and a 7. 9 kb DNA fragment by EcoRI enzymes. The cell envelope characterization of V. alginolyticus by SOS-PAGE showed the presence of 12 protein bands in the range of 29 to 112.20 kD. The preliminary information on the cell envelope characterization may help in studies relating towards development of immunostimulant against vibriosis.

Performance appraisal of microbial inoculants treating polluted surface water through bench‐scale investigation

AbstractBACKGROUNDThis study investigates the performance of microbial inoculants by exploring pollutant removal efficiency, microbial viability and substrate removal kinetics for treating polluted surface water. The morphological, elemental composition and biochemical characterization of inoculants were analyzed using field emission scanning electron microscopy with energy dispersive X‐ray spectroscopy (FESEM‐EDX) and Fourier transform infrared (FTIR) techniques. The identification of bacterial strains in polluted feed water also was performed using 16S rRNA partial sequencing. Bench‐scale efficacy of selected microbial inoculants (MI) along with control for each study was performed at variable retention times ranging from 6 to 72 h, under optimum operating conditions.RESULTSThe maximum removal (86% and 90%) of the organic load (chemical and biological oxygen demand, COD and BOD) was achieved by inoculants containing Bacillus subtilis along with other microbial species after 72 h of treatment. The microbial inoculant MI‐2 containing Paracoccus pantotrophus and Pseudomonas Putida exhibited the highest TN removal (66%) after 72 h of contact time. Adenosine triphosphate (ATP) analysis revealed that the active biomass ratio is a more precise indicator of healthy biomass instead of the conventionally used parameter MLVSS (mix liquor volatile suspended solids) in a biological treatment system, which apparently provides a significant addition to the existing knowledge base for the operational wastewater treatment plants (WTPs).CONCLUSIONIn this study, microbial inoculants were found to be frugal and viable treatment tools for the remediation of polluted surface water. Exploiting such inoculants also can overcome the inefficiencies of existing sewage treatment plants by serving as potential tools for bio‐augmenting the indigenous microbial fingerprint of aeration tank/secondary treatment systems. © 2023 Society of Chemical Industry (SCI).

Isolation and Detection of Drug-Resistant Bacterial Pathogens in Postoperative Wound Infections at a Tertiary Care Hospital in Saudi Arabia.

Surgical site infections (SSIs), especially when caused by multidrug-resistant (MDR) bacteria, are a major healthcare concern worldwide. For optimal treatment and prevention of antimicrobial resistance, it is important for clinicians to be aware of local drug-resistant bacterial pathogens that cause SSIs. To determine the frequency patterns of drug-resistant bacterial strains causing SSIs at a tertiary care hospital in Saudi Arabia. This retrospective study was conducted at the Microbiology laboratory of Al-Noor Specialist Hospital, Makkah, Saudi Arabia, and included wound swab samples from all cases of SSI between January 01, 2017, and December 31, 2021. The swabs were processed for the identification of bacterial strains and their resistance pattern to antibiotics according to the Clinical and Laboratory Standards Institute. A total of 5409 wound swabs were analyzed, of which 3604 samples (66.6%) were from male. Most samples were from the Department of Surgery (43.3%). A total of 14 bacterial strains were isolated, of which 9 were Gram-negative bacteria. The most common isolates were Klebsiella pneumoniae, followed by Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci (VRE), and vancomycin-resistant S. aureus (VRSA). In terms of MDR in 2021, the highest rate of carbapenem-resistance was in A. baumannii (97%). MDR was as follows: A. baumannii, 97%; K. pneumoniae, 81%; E. coli, 71%; MRSA, 60%; P. aeruginosa, 33%; VRE, 22%; and VRSA, 2%. This study showed that in the city of Makkah, Saudi Arabia, the rates of MDR bacteria are high, with the majority being Gram-negative.

Isolation, identification and conservation of bacteria of biotechnological interest

Introduction. The evaluation of microbial biodiversity is an important step in the process of its conservation, and the identification of bacterial strains of biotechnological interest allows their application as support for the development of sustainable agriculture technologies.
 Material and methods. From the lakes of the "La Izvor" park, 213 types of bacteria, 148 of them pathogenic, were isolated. From the non-pathogenic ones, those of biotechnological interest were determined the enzymatic properties, antimicrobial activity and were identified by molecular biological methods after that preserved by the lyophilization method with the determination of viability before and after lyophilization.
 Results. The microbial biodiversity of the "La Izvor" lakes was studied, 213 types of bacterial colonies were isolated in pure culture, which of 148 proved to be enteropathogenic belonging to the genera Escherichia, Salmonella, Shigella, Enterobacter and Klebsiella as and other strains from the Enterobacteriaceae family. The purpose of the research consisted in the isolation and identification of non-pathogenic bacteria of biotechnological interest with different properties that could serve to elaborate and improve the development of sustainable agriculture technologies. Nineteen strains with enzymatic properties and high antifungal activity against phytopathogenic fungi, were selected for molecular identification, passported, submitted to the NCNM and preserved by the lyophilization method for determination valuable properties for a long time.
 Conclusions. In the lakes of "La Izvor" park there is a very large variety of microorganisms, especially bacteria, some of which are enteropathogenic bacteria that can cause diseases in the population. Selected non-pathogenic strains stored in the NCNM can be applied against phytopathogens that cause dangerous disease and damage in agriculture major crops. As a result of lyophilization, we found that all strains showed the osmotic and thermal shocks tolerance and have a viability over 75%.
 Key words: microbial biodiversity, isolation, identification, conservation.

English

β-glucosidases are found in all domains of life and has the ability to hydrolyse the glycosidic bond between carbohydrates and non-carbohydrates residues making it a potent enzyme from an industrial and agricultural perspective. The aim of the current study was isolation, screening, and identification of bacterial strains having maximum β-glucosidase activity from soil sample of Jacobabad, Pakistan. The isolates were screened primarily, and efficient isolates were confirmed for β-glucosidase production through secondary screening. Among the different isolated strains, 1j2 was selected as the best β-glucosidase producer. The isolate showed 99% similarity with Bacillus stercoris after 16S rRNA sequencing. Different culture conditions were optimized for effective β-glucosidase production. Enhanced level of β-glucosidase was achieved at 40°C, pH 8 at 150 rpm in a β-glucosidase production medium supplemented with a combination of agricultural residues of wheat bran 0.25% (w/v) and orange peel 0.25% (w/v), using 5% inoculum. Bacillus stercoris produced a higher yield (2.89U/mg) of β-glucosidase under optimized conditions. Partial purification of β-glucosidase was achieved after 80% ammonium sulfate precipitation. The enzyme was purified and had shown maximum specific activity of 53.2 U/mg with molecular weight of approximately 36 kDa. In all the tested metals Cu2+ was observed to have inhibitory effect while Ca2+ had not affected the enzyme activity significantly. While organic solvents and surfactants had significantly reduced the β-glucosidase activity. Based on the afore mentioned abilities of purified β-glucosidase from Bacillus stercoris strain it could be a promising player for the industrial applications of lignocellulose hydrolysis found in agricultural residues for the cheap production of biofuels.

Antilisterial and Antimicrobial Effect of Salvia officinalis Essential Oil in Beef Sous-Vide Meat during Storage.

If food is contaminated with pathogens such as Listeria monocytogenes, improper cooking during sous-vide preparation can lead to foodborne illnesses. In this study, it was found that L. monocytogenes were inactivated with both heat and the essential oil of Salvia officinalis (sage EO) in beef tenderloin of the musculus psoas major that had undergone sous-vide processing. To determine whether the enhancement of the efficacy of heat treatment is prospective, L. monocytogenes and sage EO were mixed. Groups with L. monocytogenes alone and sage essential oil combined with L. monocytogenes and test groups without EO were established. The samples were vacuum-packed, inoculated with L. monocytogenes, and then cooked sous-vide for the predetermined duration at 50, 55, 60, or 65 °C. In both groups with sous-vide beef tenderloin, the total bacterial count, the coliforms bacterial count, and the amount of L. monocytogenes were assessed on days 0, 3, 6, 9, and 12. Over these days, the amounts of L. monocytogenes, coliform bacteria, and overall bacteria increased. The identification of bacterial strains in various days and categories was performed by MALDI-TOF mass spectrometry. The test group that was exposed to a temperature of 50 °C for 5 min had a higher overall bacterial count for each day that was assessed. Pseudomonas fragi and L. monocytogenes were the most isolated organisms from the test group and the treated group. To ensure the safety for the consumption of sous-vide beef tenderloin, it was found that the addition of natural antimicrobials could produce effective outcomes.

Isolation, identification and comparative analysis of 16S rRNA of Multidrug-resistant Bacteria Clinically isolated from Al Qassim Region Hospitals in Saudi Arabia

Objective: This study concluded that the antibiotic resistance and gene transfer across bacterial strains in the hospital setting are two possible explanations for the observed sequence changes in the target microorganisms.
 Methods: The 16S rDNA genes of all isolates were effectively amplified using PCR, and detailed identification results were derived from GenBank databases. The BLAST search resulted in the classification of 28 isolates into five strains. The GC content of bacterial sequences varies greatly between single species.
 Results: 16S rDNA was utilized to identify bacterial species from isolates strains results demonstrated that identification of bacterial strains. Sequences varied between and within strains, also, variation are noticed in genomic nucleotide content of isolated and identified strains. Results of the present study demonstrated that the observed heterogeneity in the sequences of our target bacterial strains may be linked to antibiotic resistance and gene transfer between bacteria that evolved as a result of the hospital environment.
 Conclusion: This study concluded that antibiotic-resistant bacteria are capable of transferring copies of their DNA encoding a resistance mechanism to other bacteria, even those that are distantly related to them. the observed heterogeneity in the sequences of our target bacterial strains may be linked to antibiotic resistance and gene transfer between bacteria that evolved as a result of the hospital environment.

MOLECULAR GENETIC IDENTIFICATION OF BACTERIA ISOLATED FROM GOAT MILK

In recent years there has been a steady trend towards an increase in the number of studies on the study of probiotics, which have a beneficial effect on the body: improve the intestinal microflora; contribute to the reduction of pathogenic bacteria; have the ability to produce substances with antimicrobial activity. In order to obtain probiotics from domestic raw materials, molecular genetic identification of bacterial strains was carried out. The object for the isolation of lactic acid bacteria was natural goat milk from the Almaty region, IE "Bekezhanova". Identification of bacterial strains was carried out on an ABI 3500 xL genetic analyzer (Applied Biosystems) using 16S primers 8F and 806R at the Scientific and Practical Center for Microbiology and Virology (Almaty). Phylogenetic analysis was performed using MEGA 6 software. Nucleotide sequence alignment was performed using the ClustalW algorithm. The results were obtained using the method of determining the direct nucleotide sequence of the 16S rRNA gene fragment, followed by comparison of the nucleotide identity with the sequences deposited in the international GenBank database. According to the results of the studies, the isolated strains of lactic acid bacteria according to the GenBank database were assigned to Lactobacillus fermentum (identity above 99.73%). These strains of microorganisms isolated from goat's milk may be promising for the production of domestic food products. On their basis it is proposed to create fermented milk products for preventive purposes.