Biotechnology Commons^™

Isolation And Characterization Of A Novel Thermostable, Halotolerant L-Asparaginase Ii From The Metagenome Of The Red Sea; Atlantis Ii Brine Pool, Aya Medhat Saleh

Archived Theses and Dissertations

L-Asparaginases (E.C. 3.5.1.1) are group of enzymes which catalyze the hydrolysis of L-asparagine to L-aspartic acid and ammonia. Many microorganisms are known to produce two types of L-asparaginase. Considerable attention has been specifically drawn to type II L-asparaginases due to their potent tumor-inhibitory activity. Various limitations, such as high toxicity, poor stability and short half-life, are associated with the commercially available L-asparaginases used in cancer therapy. Additionally, L-asparaginases have a significant role in food industry owing to their ability to reduce the levels of acrylamide, which is a known neurotoxin and a potential carcinogen, in various food products. Knowing that …

Crispr Diversity In Brine Pools Of The Red Sea: A Comparative Study Of Clustered Regularly Interspaced Short Palindromic Repeats From The Red Sea Metagenomes, Mohamed Mohamed Lotaief

Archived Theses and Dissertations

Exploration of CRISPR/Cas systems in the unique Red sea Brine pools can provide insights into host-viral interactions in highly extremophile environments. 454 Metagenomic datasets from different strata of Atlantis II, Discovery deep and Kebrit deep brine pools were mined for CRISPR arrays, and Cas proteins and compared to one another. Overall composition of CRISPR types was inferred by Cas protein HMM data, together with Cas1 phylogenetic placement using RaxML and direct repeat typing. Spacerâ viral interaction was explored using local alignments of mined spacer data to local metagenomic prophage sequences, showing and comparing specific sample CRISPR affected viral occurrences as …

Mining And Identification Of A Potential Subtilisin-Like Serine Protease From The Lower Convective Layer Of The Atlantis Ii Brine Pool In The Red Sea, Ahmed Shibl

Archived Theses and Dissertations

The Red Sea harbors a number of deep-sea brine pools with diverse chemical, physical, and geological conditions. One of the environments, the Atlantis II Brine Pool, is unique to the Red Sea. The deepest part of Atlantis II Brine Pool â the Lower Convective Layer (LCL) â is 2060 meters below the sea surface water, with 26% salinity, and a temperature of about 68 °C. Moreover, it is almost anoxic, and contains a very high concentration of heavy metals. We are interested in identifying subtilisin-like serine proteases, which are an important group of proteolytic enzymes with a broad range of …

Potential Endoglucanase Genes From The Red Sea Atlantis Ii Brine Pool: Structure, Organization And Halophilic Signature, Mohamad Maged Galal

Archived Theses and Dissertations

Cellulolytic enzymes have many industrial applications and play a major role in the process of biofuel production. Bioethanol is a cheap and clean alternative to non-renewable, polluting and expensive fossil fuel. Cellulases and hemicellulases act synergistically to degrade the cellulose polymer into glucose which can then be fermented by specific anaerobic organisms into ethanol. The overall manufacturing process occurs under harsh conditions such as low pH, high temperature and in the presence of elevated salt concentrations. The Atlantis II brine pool in the Red Sea is a unique habitat in terms of its diverse microbial community and physical conditions; high …

Triple Trouble: Examining The Effect Of Combining Mechanical Stress, Pbmcs And Cisplatin On Hepg2 Cell Death, Lalia Ziko

Archived Theses and Dissertations

In an attempt to find better cancer treatments, a new mathematical model proposed by Klika & Marsik (2009) suggests that more cancer cells could possibly be killed by applying several stress factors to tumour cells, however only as a simulation in silico. The proposed stresses include healthy cell anti-tumour effect, the biochemical effect exerted by a cytotoxic drug and a newly introduced mechanical stress. The hypothesis entails that upon applying these three stress factors together simultaneously to tumour cells, the concentration of the tumour cells decreases more than if a stress factor was applied alone. The two main objectives in …

Identification Of Potential Subtilisin-Like Serine Proteases From The Microbial Community Of The Red Sea Atlantis-Ii Brine Pool Using A Metagenomic Approach, Nadine Hosny El-Said

Archived Theses and Dissertations

The Atlantis II deep is the largest brine pool in the Red Sea of around 60 km2. It is located in the central Red Sea (21° 21' N., 38° 04' E.) at a depth of 2200 meters from the sea surface. The lower part of this pool, the lower convective layer (LCL), has extremely harsh environmental conditions characterized by a temperature of up to 68°C, pH 5.3, saturated salt (252 psu), anoxic condition, and high concentration of heavy metals. These harsh abiotic factors exert strong selective pressure in favor of microbial communities adapted to survive in such environment. Therefore, proteins …

Molecular Characterization Of Neuraminidase Surface Proteins Of Influenzavirus B Isolates From Egypt, 1999-2008, Nadean Safwan Khedr

Archived Theses and Dissertations

No abstract provided.

Deciphering The Unique Microrna Signature In Human Esophageal Adenocarcinoma: Dissecting Esophageal Adenocarcinoma Progressive Profile And Its Distinctions From Gastric Cancer, Rama Ahmed Saad Ahmed Ali

Archived Theses and Dissertations

No abstract provided.

Microbial And Chemical Profiles Of Sediments Isolated From Atlantis Ii And Discovery Deep Brine Pools In The Red Sea., Nardine G. Rasmy Marsis

Archived Theses and Dissertations

No abstract provided.

Anti-Angiogenic Effects Of Chemotherapeutic Agents And Their Enhancement With Ot-515 And S-Nach, Shimaa Adel Heikal

Theses and Dissertations

Chemotherapeutic agents have been used for the treatment of numerous types of tumors with great success. Cisplatin and Doxorubicin are among the well-known chemotherapeutic drugs that showed efficacy against various types of cancers. However, cell resistance and major side effects like chemotherapy-induced peripheral neuropathy (CIPN) are limiting factors in using these compounds. Using a combination or adjuvant compounds with anti-angiogenic effects is one of the strategies suggested to decrease resistance or ameliorate chemotherapeutic toxicity. The present study investigated the anti-angiogenic effects of Cisplatin and Doxorubicin alone and combined with Sulfated non-anticoagulant heparin (S-NACH), a low molecular weight heparin LMWH that …

Insights Into Halophilic Microbial Adaptation: Analysis Of Integrons And Associated Genomic Structures And Characterization Of A Nitrilase In Hypersaline Environments, Sarah Sonbol

Theses and Dissertations

Hypersaline environments are extreme habitats that can be exploited as biotechnological resources. Here, we characterized a nitrilase (NitraS-ATII) isolated from Atlantis II Deep brine pool. It showed higher thermal stability and heavy metal tolerance compared to a closely related nitrilase.

We also studied integrons in halophiles and hypersaline environments. Integrons are genetic platforms in which an integron integrase (IntI) mediates the excision and integration of gene cassettes at specific recombination sites. In order to search for integrons in halophiles and hypersaline metagenomes, we used a PCR-based approach, in addition to different bioinformatics tools, mainly IntegronFinder.

We found that integrons and …

Herbal Extracts As Neuroprotective Agents In An In-Vitro Model Of Aluminum Neurotoxicity, Nada Ezzelarab

Theses and Dissertations

Background: Aluminum toxicity due to environmental or industrial exposure, medical applications, or from cooking utensils is a serious medical problem. The current study aims to investigate three herbal extracts: pomegranate peel extract, Achillea fragrantissima extract, and papaya fruit extract to combat this neurotoxicity.

Methods: Chemical characterization of the three extracts were evaluated using HPLC MS while their neuroprotective activity was assayed using MTT assay on SHSY5Y cells and nitric oxide levels.

Results: Using HPLC-MS chromatography, we have identified twenty-one compounds in the hydro-alcoholic Achillea fragrantissima, seventeen were determined in the pomegranate peel, eleven were assessed in the Carica papaya …

Evaluation Of The Anticancer Potential Of Alchemilla Vulgaris Extract Against Human Neuroblastoma Cells, Yomna Moqidem

Theses and Dissertations

Neuroblastoma is one of the most challenging pediatric tumors that present heterogeneity in prognosis and survival despite intensive treatment protocols. Therefore, there is an urge to develop novel and more potent anticancer drugs. Medicinal plants have recently gained worldwide attention due to their variable activities, wide availability, and cost-efficiency. Accordingly, this study attempted to identify novel plant extracts that could show potential anticancer properties against neuroblastoma. In this study, Alchemilla vulgaris (A.vulgaris) ethyl acetate extract was prepared and evaluated for its anticancer potential against SH-SY5Y Human neuroblastoma cell line. The Phenolic content of the prepared extract was characterized …

Mining Selected Metagenomes/Metatranscriptomes For Biosynthetic Gene Clusters And Antimicrobial Resistance Genes, Ahmed Yamany

Theses and Dissertations

Antimicrobial resistance is one of the serious global challenges in the current century. The fact that resistance genes transfer between bacteria, coupled with the fact that the world is connected through complex dynamics. Studying microbial behavior and understanding the different factors coffering microbial resistance to a broad spectrum of the available drug classes, parallel with a comprehensive analysis of the natural microbial products as the primary source of the novel antibiotics, might shed some light on solutions for this problem. Microbial environments harbor a wide range of secondary metabolites (SM) with different functional groups. SMs are not directly involved in …

Assessment Of The Potential Anti-Tumour Effect Of Salvia Triloba And The Combination Of Salvia Triloba And Paclitaxel On Ovarian Cancer: Skov3 Cell Line, Naela Adel Mohammed

Archived Theses and Dissertations

No abstract provided.

Mir-590-3p Suppresses Cellular Migration And Clonogenicity And Epithelial To Mesenchymal Transition In The Hepg2 Cell Line By Targeting Mdm2 And Setd7, Alaa Youssef

Theses and Dissertations

MiRNAs signature is dysregulated in various types of cancer, and several miRNAs have a dual regulatory role either as tumor suppressors or oncogenes depending on the tissue context. MiR-590-3p has been previously identified to regulate different cancers, yet its role in hepatocellular carcinoma (HCC) is still elusive with contradictory findings. In our study, the expression levels of miR-590-3p, as well as its function in HCC, were examined in two different HCC cell lines: HepG2 and SNU449 that represent an early and advanced stage of HCC, respectively. Real-time Polymerase Chain Reaction analysis revealed that miR-590-3p is downregulated in HCC and its …

Circulating Micrornas In Neuromuscular Disorders, Nahla Mousa

Theses and Dissertations

Identification of the mutations and genetic causes of the muscular diseases is performed for the muscular dystrophies, atrophies and other genetic diseases using current molecular high throughput techniques that precisely allocate the defected genes and detect the aberration in the expressed proteins responsible for any phenotype. For example, more than 2000 mutations in the DMD gene were identified in Duchenne Muscular Dystrophy patients or the milder form of the disease Becker Muscular Dystrophy. Detection of different mutation in the same gene has critical role as biomarkers in disease diagnosis, since the severity of the symptoms is usually associated with the …

Role Of Microrna-208a As A Diagnostic And Prognostic Marker In Patients With St-Elevation Myocardial Infarction, Abou Bakr Mohamed Mohamed Hammad Salama

Theses and Dissertations

Acute Myocardial infarction (AMI) is the leading cause of death worldwide. Diagnosis of AMI depends on presenting symptoms, electrocardiogram (ECG), and cardiac troponins (cTns). Troponins are not good markers for patients presenting at the first hour of chest pain, so there is still a need for a marker that can be detected within the first hour of presentation, with high specificity and sensitivity, guide the medical decisions and give good insight on the expected prognosis. Previous studies reported miR-208a as a cardiac specific microRNA that can be detected in the plasma as early as 15 min of cardiac insult and …

In-Depth Analysis Of Culturable Microalgae Diversity In The River Nile At Different Locations, Amal Abouel-Fetouh Badr

Theses and Dissertations

Identifying microalgae diversity in an ecosystem is essential not only to understand their impact on the ecosystem but also to recognize their potential in various applications that benefit humankind. The great biodiversity of microalgae and their ability to survive in drastic environmental by modifying their apparent phenotypes and cellular compositions has led to the continuous need for the development and modification of the current microalgae identification methods. This study evaluates the current culture-based identification method using two commonly used media (BG-11 and BBM) and the assessment of two modified media (MM) and a plant media (MS) to identify microalgae diversity …

Mining For Specialized Metabolism Genes In Red Sea Brine Pool Prokaryotic Metagenomes For Antibacterial And Anticancer Activities, Laila Ziko

Theses and Dissertations

Antibiotic and anticancer drug resistance are current global health threats, thus new antibiotics and anticancer agents are required to treat the strains and cancers that are currently untreatable with the available drug spectrum. One way to search for new chemotherapeutics is to search nature, particularly metagenomes of un-cultured microbial communities. A subset of specialized metabolites (SMs) produced by microbes confer activities of pharmaceutical importance, such as antibacterial and anticancer effects, and are coded by specialized metabolism gene clusters (SMGCs) in the organisms’ genomes. We aimed to search for SMGCs in the metagenomes of Red Sea brine microbial communities by employing …

Identification And Characterization Of A Novel Thermohalophilic Esterase From The Red Sea: Atlantis Ii Brine Pool, Yasmine Mustafa Mohamed

Theses and Dissertations

Industrial (white) biotechnology poses an increasing demand for novel biocatalysts that are robust under a wide range of conditions. Traditionally, biocatalysts were isolated from cultured isolates, however, less than 1% of microorganisms are culturable. Therefore, it became evident that the unculturable majority holds a great potential for the discovery of novel biocatalysts. Metagenomics is an invaluable tool for accessing the genomes of the uncultured majority and has led to the isolation of a large number of biocatalysts from various environments. Extreme environments such as hydrothermal vents, brine pools and glaciers, are an attractive source for biocatalysts. Biocatalysts from these environments …