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The advancements in biotechnology over time have led to an increase in the demand of pure, soluble and functionally active proteins. Recombinant protein production has thus been employed to obtain high expression of purified proteins in bulk. E. coli is considered as the most desirable host for recombinant protein production due to its inexpensive and fast cultivation, simple nutritional requirements and known genetics. Despite all these benefits, recombinant protein production often comes with drawbacks, such as, the most common being the formation of inclusion bodies due to improper protein folding. Consequently, this can lead to the loss of the structure-function relationship of a protein. Apart from various strategies, one major strategy to resolve this issue is the use of molecular chaperones that act as folding modulators for proteins. Molecular chaperones assist newly synthesized, aggregated or misfolded proteins to fold into their native conformations. Chaperones have been widely used to improve the expression of various proteins which are otherwise difficult to produce in E. coli. Here, we discuss the structure, function, and role of major E. coli molecular chaperones in recombinant technology such as trigger factor, GroEL, DnaK and ClpB.

Pcal_0768 gene encoding an amylomaltase, a 4-α-glucanatransferase belonging to family 77 of glycosyl hydrolases, from Pyrobaculum calidifontis was cloned and expressed in Escherichia coli. The recombinant protein was produced in E. coli in soluble and active form. However, the expression level was not very high. Analysis of the mRNA of initial seven codons at the 5′-end of the gene revealed the presence of a hair pin like secondary structure. This secondary structure was removed by site directed mutagenesis, without altering the amino acids, which resulted in enhanced expression of the cloned gene. Recombinant Pcal_0768 exhibited optimal amylomaltase activity at 80 °C and pH 6.9. Under these conditions, the specific activity was 690 U/ mg. Recombinant Pcal_0768 was highly thermostable with a half-life of 6 h at 100 °C. It exhibited the highest kcat value among the characterized glucanotransferases. No metal ions were required for activity or stability of the enzyme. Recombinant Pcal_0768 was successfully employed in the synthesis of modified starch for producing thermoreversible gel. To the best of our knowledge, till now this is the most thermostable enzyme among the characterized amylomaltases. High thermostability and starch modification potential make it a novel and distinct amylomaltase.

Preeclampsia (PE) presents a major obstetrical problem for mother and fetus which is characterized by the onset of hypertension and proteinuria in formerly normotensive women. Altered folate-mediated one-carbon metabolism is one of the factors for PE development either due to nutritional insufficiencies such as folate deficiency or polymorphisms in genes that code for the key enzymes of the cycle. Commonly, there are four genes in the cycle whose polymorphisms have been described in relation to PE. These factors could cause elevation of homocysteine; the toxic metabolite, which subsequently leads to the development of PE. Sufficient levels of folate have been considered important during pregnancy and may reduce the risk of development of PE. This review aims at discussing genetic polymorphisms and nutritional deficiencies as probable predisposing factors and suggests considering fetal genotypes, varied ethnicities, and interaction of various other factors involved to render better conclusiveness to the present studies.

Background MicroRNAs (miRNAs) are small RNA molecules that modulate post-transcriptional gene regulation. They are often used as promising non-invasive biomarkers for the early diagnosis of cancer. However, their roles in assisted reproduction are still unknown. Methods This prospective study was designed to evaluate the expression profiles of seven extracellular miRNAs (miR-7-5p, miR-202-5p, miR-378-3p, miR-224, miR-320a, miR-212-3p, and miR-21-5p) in human follicular fluid (FF) to explore the outcomes of in vitro fertilization (IVF). Of 255 women, 145 were without polycystic ovary syndrome (PCOS), and their ovarian assets were normal (NOR), while 110 were with normo-androgenic PCOS. Results The combination of six FF miRNAs expression profile discriminated between PCOS and NOR women with a sensitivity of 79.2% and a specificity of 87.32% (AUC = 0.881 [0.61; 0.92], p = 0.001). MiR-202-5p significantly had a lower abundance level, and miR-378-3p had a high abundance level in pooled FF samples from patients treated with human menopausal gonadotropin (hMG) than those treated with recombinant follicle-stimulating hormone (rFSH) (p < 0.001). Our results showed that miRNA-320a was significantly different in top-quality embryos versus non-top-quality embryos on day 3 in NOR patients with a sensitivity of 80% and specificity of 71%, (AUC = [0.753 (0.651; 0.855)], p = 0.001). For clinical pregnancy outcome prediction, FF miRNA-21 exhibited high sensitivity (74.8%) and specificity (83.7%) with the AUC value of 0.774 (0.682; 0.865). Conclusion Conclusively, our results provide evidence that miR-7-5p, miR-378-3p, miR-224, miR-212-3p were a differentially high expression in normo-androgenic PCOS patients than NOR patients. While miRNA-320a was significantly different in top-quality embryos versus non-top-quality embryos on day 3 (p = 0.001). The expression level of FF miR-212-3p was significantly related to the probability of embryos to develop into a high-quality blastocyst in patients with normal ovarian reserve., Lahore institute of Fertility and Endocrinology, Hameed Latif Hospital, Lahore, Pakistan, Lahore institute of Fertility and Endocrinology, Hameed Latif Hospital, Lahore, Pakistan.

Background Non-Small Cell Lung Carcinoma is one of the major cause of morbidity and mortality worldwide with an incidence rate of 1.3 million cases per year. Heat shock protein 90 (HSP90) is a promising drug target in cancer treatment. HSP90 is required to activate numerous eukaryotic proto-oncogenic protein kinases, hence play a prominent role in cancer. Method We reviewed fifty-five articles to highlight the importance of HSP90 in NSCLC and the recent developments of its inhibitors. Results This review showed that HSP90 inhibitors i.e. Ganestespib have shown great potential in the treatment of non-small cell lung carcinoma (NSCLC). Different HSP90 inhibitors has been designed till date that acts as effective drugs in tumour suppression. However, the utility of these drugs has been limited due to several drawbacks including hepato-toxicity, poor solubility, and poorly tolerated formulations. Conclusion The goal of this review is to present the data in support of use of HSP90 inhibitors in NSCLC and to provide an overview of the on-going clinical trials involving new-generation HSP90 inhibitors.