Purification and identification of a surfactin biosurfactant and engine oil degradation by Bacillus velezensis KLP2016.

Engine oil used in automobiles is a threat to soil and water due to the recalcitrant properties of its hydrocarbons. It pollutes surrounding environment which affects both flora and fauna. Microbes can degrade hydrocarbons containing engine oil and utilize it as a substrate for their growth. Our results demonstrated that cell-free broth of Bacillus velezensis KLP2016 (Gram + ve, endospore forming; Accession number KY214239) recorded an emulsification index (E24%) from 52.3% to 65.7% against different organic solvents, such as benzene, pentane, cyclohexane, xylene, n-hexane, toluene and engine oil. The surface tension of the cell-free broth of B. velezensis grown in Luria-Bertani broth at 35 °C decreased from 55 to 40 mN m-1at critical micelle concentration 17.2 µg/mL. The active biosurfactant molecule of cell-free broth of Bacillus velezensis KLP2016 was purified by Dietheylaminoethyl-cellulose and size exclusion chromatography, followed by HPLC (RT = 1.130), UV-vis spectrophotometry (210 nm) and thin layer chromatography (Rf = 0.90). The molecular weight of purified biosurfactant was found to be ~ 1.0 kDa, based on Electron Spray Ionization-MS. A concentration of 1980 × 10-2 parts per million of CO2 was trapped in a KOH solution after 15 days of incubation in Luria-Bertani broth containing 1% engine oil. Our results suggest that bacterium Bacillus velezensis KLP2016 may promise a new dimension to solving the engine oil pollution problem in near future.

Lipopeptide(s) associated with human microbiome as potent cancer drug.

Human microbiota comprises of trillions of microbes which have evolved with and continued to live on/ within their human hosts. Different environmental factors and diet have a large impact upon human microbiota population. These microorganisms live in synergy with their hosts and are beneficial to the host in many different ways. Many microorganisms help to fight against human diseases. Cancer is one such diseases which effects a large human population often leading to death. Cancer is also one of the most fatal human diseases killing millions of people world-wide every year. Though many treatment procedures are available but none is 100 % effective in curing cancer. In this review, we seek to understand the role of human microbiota in cancer treatment. Lipopeptide(s) (LPs) produced by different microorganisms can act as efficient drug(s) against cancer. LPs are low molecular weight lipo-proteins that are also known for their anti-cancer activities. As human microbiota belongs to an environment within the host body, a drug prepared using these microorganisms will be easily accepted by the body. This novel approach of using LPs produced by human microbiota can be considered for the much needed change in cancer treatment. Therefore, it is proposed that research should focus on the host-microbe interaction which could pave the way in understanding role played by these microorganisms in cancer treatment.

Phosphatidylserine: A cancer cell targeting biomarker.

Cancer is a leading cause of mortality and morbidity globally. Many prominent cancer-associated molecules have been identified over the recent years which include EGFR, CD44, TGFbRII, HER2, miR-497, NMP22, BTA, Fibrin/FDP etc. These biomarkers are often used for screening, detection, diagnosis, prognosis, prediction and monitoring of cancer development. Phosphatidylserine (PS) is an essential component in all human cells which is present on the inner leaflet of the cell membrane. The oxidative stress causes exposure of PS on the surface of the vascular endothelium in the cancer cells (lung, breast, pancreatic, bladder, skin, brain metastasis, rectal adenocarcinoma etc.) but not on the normal cells. The external PS is regulated by calcium-dependent flippase activity. Cancer cell lines with high surface PS have low flippase activity and high intracellular calcium content. Human Annexin-V, PS targeting antibodies (PGN635 and bavituximab and mch1N11), lysosomal protein, phospholipid Saposin C dioleoylphosphatidylserine (SapC-DOPS), peptide-peptoid hybrid PPS1, PS-binding 14-mer peptide (PSBP-6) and hexapeptide (E3) have been reported to target PS present on cancer cell surface. High expression of CD47 inhibits tumor cell phagocytosis by macrophages. The PS cancer biomarker has also been used to target the drugs to cancer cells specifically without affecting other healthy cells. Currently, the fusion protein (FP) consisting of L-methionase linked to human Annexin-V has been reported to target the cancer cells. The FP catalyzes the conversion of non-toxic prodrug selenomethionine into toxic methyl selenol which thus also prevents the methionine (essential amino acid) supplementation to the cancer cells.

Molecular characterization and bioinformatics studies of a lipase from Bacillus thermoamylovorans BHK67.

A bacterium isolated from a hot-water spring identified as Bacillus thermoamylovorans BHK67 successfully produced a thermotolerant extracellular alkaliphilic lipase. The lipase was purified to homogeneity by anion exchange chromatography with 15-fold purification and 12.1% yield. The lipase appeared to be a hexameric protein as it possessed a single band of Mr 25kDa in SDS PAGE and 150kDa in Native PAGE. DLS analysis of purified Bacillus thermoamylovorans BHK67 lipase (BTL) also showed the molecular integrity, homogeneity and stability of the enzyme. The purified lipase showed maximum activity at pH 7.5 with a half-life of 10.5h at 55°C. Kinetic study of purified lipase by Lineweaver-Burk plot provided Km (7.7mM),Vmax (90.9U/mL/min),Kcat (227.3s-1) and Kspec (29.4mMs-1) for substrate p-nitrophenylpalmitate.The purified lipase also showed astonishing stability following exposure to ethanol, n-propanol, iso-propanol, n-butanol and DMSO. Amino acid characterization of BTL by MALDI-TOF-MS showed considerable resemblance with lysophospholipase L1 related esterase of Lactobacillus ozensis DSM 23829. Experimental coupled molecular modeling postulated a structure-activity correlation of BTL as a probable contender in degradation of xenobiotic compounds, biocatalysis, biotransformation of compounds, synthesis of optically active compounds, foodstuff industry, anticancer therapeutics etc.

Lead Phytochemicals for Anticancer Drug Development.

Cancer is a serious concern at present. A large number of patients die each year due to cancer illnesses in spite of several interventions available. Development of an effective and side effects lacking anticancer therapy is the trending research direction in healthcare pharmacy. Chemical entities present in plants proved to be very potential in this regard. Bioactive phytochemicals are preferential as they pretend differentially on cancer cells only, without altering normal cells. Carcinogenesis is a complex process and includes multiple signaling events. Phytochemicals are pleiotropic in their function and target these events in multiple manners; hence they are most suitable candidate for anticancer drug development. Efforts are in progress to develop lead candidates from phytochemicals those can block or retard the growth of cancer without any side effect. Several phytochemicals manifest anticancer function in vitro and in vivo. This article deals with these lead phytomolecules with their action mechanisms on nuclear and cellular factors involved in carcinogenesis. Additionally, druggability parameters and clinical development of anticancer phytomolecules have also been discussed.

L-methionase: a therapeutic enzyme to treat malignancies.

Cancer is an increasing cause of mortality and morbidity throughout the world. L-methionase has potential application against many types of cancers. L-Methionase is an intracellular enzyme in bacterial species, an extracellular enzyme in fungi, and absent in mammals. L-Methionase producing bacterial strain(s) can be isolated by 5,5'-dithio-bis-(2-nitrobenzoic acid) as a screening dye. L-Methionine plays an important role in tumour cells. These cells become methionine dependent and eventually follow apoptosis due to methionine limitation in cancer cells. L-Methionine also plays an indispensable role in gene activation and inactivation due to hypermethylation and/or hypomethylation. Membrane transporters such as GLUT1 and ion channels like Na(2+), Ca(2+), K(+), and Cl(-) become overexpressed. Further, the α-subunit of ATP synthase plays a role in cancer cells growth and development by providing them enhanced nutritional requirements. Currently, selenomethionine is also used as a prodrug in cancer therapy along with enzyme methionase that converts prodrug into active toxic chemical(s) that causes death of cancerous cells/tissue. More recently, fusion protein (FP) consisting of L-methionase linked to annexin-V has been used in cancer therapy. The fusion proteins have advantage that they have specificity only for cancer cells and do not harm the normal cells.

Pharmacological and clinical evaluation of L-asparaginase in the treatment of leukemia.

L-Asparaginase is an effective antineoplastic agent, used in the acute lymphoblastic leukemia chemotherapy. It has been an integral part of combination chemotherapy protocols of pediatric acute lymphoblastic leukemia for almost 3 decades. The potential of L-asparaginase as a drug of leukemia has been a matter of discussion due to the high rate of allergic reactions exhibited by the patients receiving the medication of this enzyme drug. Frequent need of intramuscular injection has been another disadvantage associated with the native preparation. However, of late these clinical complications seem to have been addressed by modified versions of L-asparaginase. PEG-L-asparaginase proves to be most effective in this regard. It becomes important to discuss the efficacy of L-asparaginase as an antileukemic drug vis-a-vis these disadvantages. In this review, an attempt has been made to critically evaluate the pharmacological and clinical potential of various preparations of L-asparaginase as a drug. Advantages of PEG-L-asparaginase over native preparations and historical developments of therapy with l-asparaginase have also been outlined in the review below.