Journal of Experimental and Molecular Biology
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EVOLUTION OF CRISPR SYSTEM AND THEIR APPLICABILITY TO GENOME EDITING IN BACTERIA
Get PDFRecombinant DNA and genetic engineering technologies have made it possible to manipulate and carry out important advances in biology. However designing reliable, safe and accurate system for genome editing in prokaryotes and eukaryotes has been an issue for a long time. Enzymes (such as polymerases, ligases, and restriction endonucleases) and the polymerase chain reaction (PCR) provided ways to isolate genes and gene fragments, as well as to introduce mutations into gens in vitro, in cells and in a model organism. Today, the field of biology is undergoing a transformative phase with the advent of easy genome engineering using RNA-programmable CRISPR-Cas9. The CRISPR-Cas9 system is an immune system present in prokaryotes that allows the identification of exogenous DNA or RNA molecules. The Cas9 endonuclease is associated with a guide RNA molecule (RNAg) that allows it to form base pairs with target DNA or RNA sequencing, allowing Cas9 to introduce a site-specific double-strand break. Thanks to this breakthrough in genetic engineering Doudna Jennifer and Charpentier Emmanuelle were awarded the Nobel Prize in Chemistry in 2020 (Doudna and Charpentier., 2014). In what follows I will talk about the applicability of this system to edit bacterial genomes by punctiform, genetic and metabolic modifications
Amino acid Profile of Trichosantes cucumerina from four Geopolitical Zones in Nigeria.: The amino acid composition ripe snake gourd from four geopolitical zones in Nigeria.
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The aim of the study was to investigate the amino acid profile of five (5) ecotypes of T. cucumerina (snake gourd) from four geopolitical zones in Nigeria. Fresh ripe fruit of T. cucumerina was collected from the research farm of Michael Okpara University of Agriculture, Umudike, Umuahia Abia State Nigeria. The seeds were extracted from the fresh ripe fruit, blended and stored in the refrigerator for further use. Amino acid was determined using HPLC apparatus. Glutamate had the highest protein content which ranged from 14.4643-15.23094g/100 of protein; followed by aspartate with 2.0981-12.20628g/100 of protein, leucine with 7.20846-8.9831g/100 of protein. Glycine protein was the least with a ranged of 0.0435-4.2118g/100. The snake gourd amino acid profile was found highest in North-Central ecotype (Benue State) with a ranged of (1.115-14.46497) g/100 protein; followed by South-West ecotype (Ekiti and Osun States) with a range of (0.87481-12.20628), (0.0435-15. 23094) g/100protein respectively. South- East ecotype (Abia State) T.cucumerina result ranged from (0.54978-14.67031)g/100 protein. The least result was found in South-South ecotype snake gourd with 0.35514-14.46243g/100 protein. Variation in amino acid content in ripe fruits of T. cucumerina accessions investigated revealed that glycine had the highest coefficient variation of 140% followed by tyrosine with 54.31%, aspartate 47.56%, and least from valine 5.62%, isoleucine 7.05%, tryptophan 6.51% and cysteine 6.82% glutamate 2.14%. There were three clusters in the dendrogram of amino acid composition of selected snake tomato ecotypes investigated. Amino acid result revealed that the highest amino acid content was found in snake gourd from the North -Central and least in South-South ecotype respectively.
Keywords: Amino acid, Trichosanthes cucumerina, Ecotypes, South-East, South-South, South-West and North Central
Aqueous and ethanolic leaf extracts leaf extracts of Lophira Lanceolata properties effect in mice infected with Plasmodium berghei
Get PDFThis study was to determine the effects of Lophira lanceolata leaf extracts on haematological, biochemical, and histopathological parameters of the mice in the transmission of Plasmodium parasites using mice infected with P.berghei as a model. A total of 196 experimental mice divided into 15 groups in a randomized block design and replicated four times with four mice in each group were used for this study. Thirty six (36) mice were used for acute toxicity test, 50 each for haematological, biochemical, and histopathological analyses. Experimental mice were inoculated intraperitoneally with standard inoculum of 1 x 107 P.berghei parasitized red blood cells on first day (DO). Data analysis was done using student’s t-test and one way analysis of variance with multiple comparison tests. Aqueous leaf extract exerted significant (p < 0.05) non-dose dependent reduction in parasitaemia level with chemosuppression of 48.79%, 24.26%, 29.38% and 80.32% at 10, 100, 200 mg/kg body weight and 5mg/kg body weight chloroquine treated groups respectively. Dose level of 10, 100, 200 mg/ kg body weight of both aqueous and ethanolic leaf extract produced significant increases in aspartate amino transferase, alanine amino transferase, total bilirubin, cholesterol, triglycerides and urea profiles of infected treated mice compared with the control. At 200mg /kg body weight of aqueous extract there was a significant decrease (p < 0.05) in weight of liver and kidney organs in the infected treated mice compared with the control. The results of histopathological examinations of the liver organs of the mice were characterized by tissue stromal proliferation, enlarged hepatocytes and disorganized sinusoids and lamina of hepatic cells.The results of histopathological examination of kidneys showed no histopathological changes.The aqueous and ethanolic leaf extracts of Lophira lanceolata plant showed significant antiplasmodium activities comparable to chloroquine drugs.The leaf extracts of Lophira lanceolata plant had gametocytocidal action on P. berghei. The results of the haematological, biochemical and histopathological examinations indicated that caution should be exercised while taking the plant extract as an antimalarial agent
Hoogsteen Base Pairings: A New Paradigm for DNA Replication, DNA Recognition, and DNA Repair
Get PDFIn contrast to Watson-Crick (WC) base pairing, Hoogsteen (HG) base pairing involves flipping a purine base 180° between its anti and syn conformation. Recent studies have shown that HG pairs coexist in dynamical equilibrium, and several biological functions depend on them. This significance has stirred computational research on this base-pairing transition. However, a methodical reproduction of sequence variations has continued to be out of reach. It is becoming increasingly clear that Hoogsteen base pairs play a crucial role in DNA replication, recognition, damage repair, and incorrect sequence repair. The Protein Data Bank contains a variety of Hoogsteen base pairing modes that include the preference for A–T versus G–C bps, TA versus GG steps, and a preference for 5'-purines at terminal ends. RNA A-form duplexes are strongly disfavored by Hoogsteen base pairs, in stark contrast to B-form DNA. Therefore, N1-methyl adenosine and N1-methyl guanosine, which transpire in DNA as alkylation impairment and in RNA as posttranscriptional adjustments, have great differences in effects. They create G–C+ and A–U Hoogsteen base pairs in duplex DNA that preserve the structural integrity of the double helix, but obstruct base pairing altogether and induce local duplex melting in RNA, providing a mechanism for potently disrupting RNA structure through posttranscriptional modifications. In duplex DNA, they maintain the structural integrity of the double helix by creating G–C+ and A–U Hoogsteen base pairs, but block base pairing altogether and cause local duplex melting in RNA, thus providing a potent means for disrupting RNA structure post transcriptionally. As a result of the markedly different inclinations for B-DNA and A-RNA to form Hoogsteen base pairs, they may be able to balance the opposing demands of maintaining genome stability and dynamically modulating the epitranscriptome. This review examines the occurrence of Hoogsteen base pairs in DNA and RNA duplexes
PHYLOGENETIC ORIGIN OF FIVE ALGERIAN SHEEP BREEDS
Get PDFIn order to perform a phylogeny study of five Algerian sheep breeds, a sample of 26 animals belonging to Algerian sheep breeds was analysed. Multiple alignment of mitochondrial sequences was performed after the introduction of other highly similar mitochondrial sequences from different regions of the world. 20 different haplotypes were observed, with a nucleotide diversity of 0.60863 and a haplotype diversity of 0.932. The evolutionary history deduced from the study of genetic distances, and phylogeny based on the maximum likelihood model, showed that these five local breeds belong to the mixture of the two world haplogroups (A and B)
PSYCHOPHARMACOLOGIC TARGETS IN PERSONALIZED PSYCHIATRY
Get PDFThe advances made on genetic influence on response and side effects of psychiatric pharmacotherapy improved the concept of personalized psychiatry. The current evidence suggests that testing can be useful in patients who did not respond or tolerate at least one previous pharmacotherapy. Approximately 90% of all drugs are metabolized by only few different cytochrome enzymes. Pharmacogenetic research has provided important evidence of CYP functional polymorphisms in psychiatric treatment, with numerous studies associating their presence with the variability observed in response to treatment. The study of candidate genes involved in the pharmacokinetics of antidepressants has provided sufficiently strong scientific evidence for clinical applications. These genes encode the cytochrome P450 enzymes and are responsible for the metabolism of antidepressants. Pharmacogenetic testing is thus becoming a useful and increasingly useful tool for antidepressant pharmacotherapy. The efficacy of antidepressant action has been associated with several polymorphisms, located on the gene encoding proteins considered to be involved in the various mechanisms of action of antidepressant treatments
Acquired Antibiotic Resistance
Get PDFAntibiotics are chemicals used to control bacterial infections, produced by microorganisms (fungi, some bacteria) or obtained synthetically or semi-synthetically. The discovery of antibiotics has revolutionized the medical system, reducing morbidity and mortality rates and improving quality and length of life. Antibiotics affect essential processes in the bacterial cell, but bacteria have adapted to their action by developing antibiotic resistance. Though multidrug-resistant bacteria have emerged, they threaten the healthcare system globally by making it difficult to find effective antibiotics. This review focuses on the mechanisms leading to acquired antibiotic resistance, namely mutations and horizontal gene transfer, and on mobile genetic elements associated with antibiotic resistance (plasmids, transposons, and integrons) that disperse antibiotic resistance genes between bacteria
OPTIMIZATION OF PLASMA CELL ENRICHMENT FOR CNV DETECTION BY SNP ARRAY AND MLPA
Get PDFMultiple myeloma is characterized by the uncontrolled proliferation of an atypical plasma cell clone. The main factor preventing the characterization of plasma cells is their low rate in the analyzed samples. Through this study we tried to highlight the necessity of enrichment of MM samples to be analyzed by MLPA and SNParray. Samples from 5 patients diagnosed with MM were investigated and 2 of them were enriched by magnetic sorting with anti-CD138 antibodies and analyzed by SNParray and MLPA. Unsorted samples showed a lower incidence of abnormalities. By analyzing the data, we concluded that even a 30% malignant cell infiltration in the MM sample is not enough and the magnetic sorting is a mandatory for the enrichment of target cells from the sample.
 
ANTI-DIABETIC POTENTIAL OF HYPHAENE THEBAICA FRUIT IN STREPTOZOTOCIN-INDUCED DIABETIC RATS.
Get PDFComplications of Diabetes mellitus caused by persistent hyperglycemia is a challenge in management of the disease as synthetic drugs used are often expensive, specific and associated with side effects. This study was aimed to determine the anti-diabetic potential of mesocarp extract of Hyphaene thebaica fruit in streptozotocin-induced Diabetic rats. The hypoglycemic effects of methanol, aqueous and ethylacetate extract of Hyphaene thebaica fruit oral glucose tolerance test (OGTT) were determined followed by the effects of the ethylacetate extract on body weight, blood glucose, liver and kidney. Glucose was fed to rats the 30 minutes after pretreatment with extract, followed by measurement of blood glucose levels at 0, 30, 60, 90, 120, and 240 minutes to assess the effect of the extracts on blood glucose levels of the glucose loaded animals. The rats were also divided into six groups and treated ethylacetate extract daily by intragastric tube for four weeks. The result revealed the ethylacetate extract was more hypoglycemic in OGTT than the other extracts. There was a significant (p < 0.05) improvement in body weight of rats administered ethylacetate extract at 400 mg and 200 mg/kg body weight with significant (p < 0.05) decrease in blood glucose, AST, GGT, creatinine, and urea levels. Conclusively, H. thebaica can be used in the management of diabetes evident to its hypoglycemic effects and significant improvement in weight and hepato-renal function
EXPERIMENTAL EVALUATION OF THE PULMONARY EDEMA INDUCED BY THE VENOM OF THE SCORPION TITYUS ASTHENES IN RATS
Get PDFThe species Tityus asthenes has been responsible for scorpion sting deaths in Panama. Pulmonary edema is one of the main causes of death registered by scorpionism. In the present work, we determined the capacity of the venom of the scorpion Tityus asthenes to induce pulmonary edema in rats. The ability of T. asthenes venom to induce acute pulmonary edema in rats was determined using four approaches: (1) the difference in wet weight using the lung index between treated and untreated lungs; (2) histological analysis; (3) changes in pulmonary vascular permeability; and (4) total leukocyte count obtained from bronchoalveolar lavage. We found that histological sections of venom-treated lungs showed moderate pulmonary edema, and an increase in total leukocyte count compared to control samples. However, the pulmonary index and the vascular permeability of venom-treated lungs were similar to those of control samples. We conclude that the venom of T. asthenes scorpions can induce moderate pulmonary edema in rats. The experimental model was validated for future studies on the pathophysiology of pulmonary edema caused by the venom of scorpions of the genus Tityus in Panama