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Enzymatic Amino Acid Deprivation Therapies Targeting Cancer
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Carla S. S. Teixeira, Henrique S. Fernandes, Sérgio F. Sousa, Nuno M. F. S. A. Cerqueira
Some cancers such as metastatic melanoma (MM), prostate carcinomas, hepatocellular carcinoma (HCC) (Dillon et al., 2004) non-Hodgkin’s lymphoma, Hodgkin’s lymphoma, pancreatic carcinoma, osteosarcoma, and malignant pleural mesothelioma and some breast tumours (Qiu et al., 2015) have an elevated requirement for l-ARG due to the deficient expression of ASS1 that results in l-ARG auxotrophy (Feun et al., 2008, 2012, 2015). Arginine deiminase (ADI, EC 3.5.3.6) is an enzyme with high affinity to l-ARG that catalyses the conversion of l-ARG into citrulline and ammonia. The cancer cells who do not express ASS1 are unable to re-synthesize l-ARG from citrulline, which culminates in the full deprivation of an amino acid that is imperative for their survival (Shen et al., 2003).
Enzymes for Prodrug-Activation in Cancer Therapy
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2020
PEGylated enzymes have found wider applications in cancer therapy with the aim to deprive malignant cells of nutrients such as amino acids essential for their growth, e.g., in connection with protein biosynthesis (see also Chapter 8, Vol. 4 of this Series on Biocatalysis); such a strategy makes use of enzymes that degrade these amino acids as well as of the fact that many cancer types are deficient in enzymes required for amino acid synthesis; such an enzyme is argininosuccinate synthetase-1 that in a sequential action with argininosuccinate lyase catalyzes the synthesis of arginine from citrulline. PEG-L-asparaginase (Oncaspar) was the first to achieve US FDA approval in 1994 for the treatment of acute lymphoblastic leukemia and lymphoma. L-asparaginase depletes the amino acid asparagine (see the scheme on the previous page) that is essential for tumor growth. PEG-recombinant arginine deiminase (PEG-rhADI) has also been reported to inhibit in vivo and in vitro proliferation of hepatocellular carcinoma cells (Cheng et al., 2007) because this enzyme catabolizes arginine to citrulline (see the scheme on the previous page). Miraki-Moud et al. (2015) found that arginine deprivation using PEGylated arginine deiminase (ADI-PEG 20) has activity against primary acute myeloid leukemia cells in vivo. The application of ADI-PEG 20 in combination with cytarabine (cytosine arabinoside, a chemotherapy medication) was more effective than either treatment alone. A review published by Feun et al. (2015) deals with recent studies that focus on Arg-dependent malignancies with arginine-degrading enzymes, including arginase and arginine deiminase as well as a discussion of mechanisms of resistance that cancers develop after such drug exposure. The potential of arginine deiminase as an antitumor agent has been reviewed by Somani and Chaskar (2018). There is an increasing interest in the development of novel types of human arginase for targeting arginine-dependent cancers, in particular a pegylated enzyme (hArg I [Co]-PEG5000) that has shown good efficacy in depleting arginine and where the two essential manganese (II) ions are replaced with cobalt (Phillips et al., 2013). Khoury et al. (2015) presented a study according to which human recombinant arginase I (Co)-PEG5000 is selectively cytotoxic to human glioblastoma cells. For an early review that in addition focuses on the mechanism of action of drug conjugates, see Duncan (2006). A more recent review is from Scomparin et al. (2017) and discusses advances and future perspectives of both polymer-directed enzyme prodrug therapy (PDEPT) and polymer enzyme liposome therapy (PELT); the latter is briefly treated in the next Section.
Neutralization of acidic soil using Myxococcus xanthus: Important parameters and their implications
Published in Geosystem Engineering, 2021
MinJung Cho, SeonYeong Park, EunYoung You, ChangGyun Kim
From these experiments, it can be concluded that the pH was eventually increased by ammonia production during the metabolism of M. xanthus. The peptone and beef extract contained in NB medium used for its growth was composed of various amino acids and peptides. And, M. xanthus is reported to produce ammonia by MICP of amino acids (Castro-Alonso et al., 2019). Furthermore, the nitrogenous compounds and nucleosides produced by microbial growth could be converted to ammonia, which in turn producing ammonium ion and hydroxide ion. It was due to the hydrolytic breakdown by hydrolase, deaminase, and ammonia-lyase enzyme distributed in M. xanthus such as arginine deiminase (arcA) (Richard & Foster, 2004), adenosine deaminase (add)(Sun et al., 2012), histidine ammonia-lyse (hutH) (Pohlman & Mill, 1983), etc. Through such a metabolic system, microorganisms can resist acidic conditions by raising pH with the help of producing ammonia. The whole genome sequence data of M.xanthus (ATCC 25232TM) was compared on the ATCC website for identifying the enzyme of this strain. (https://genomes.atcc.org/genomes/78b49a076c08427e)
An overview of cell disruption methods for intracellular biomolecules recovery
Published in Preparative Biochemistry & Biotechnology, 2020
Tatiane Aparecida Gomes, Cristina Maria Zanette, Michele Rigon Spier
According to Halim et al.[54] and Kim et al.,[55] the effectiveness of cell disruption is higher when the cellular concentration increases. This behavior was verified in a study carried out by Patil et al.,[56] aiming to release arginine deiminase from Pseudomonas putida. The authors also observed the number of passes influenced the process efficiency, as well as reported to the HPH system. However, the subsequent passes were less effective in the cell disruption, due to the high concentration of intact cells as well as the release of proteins and DNA. Another parameter that may influence the cell disruption efficiency is the cell homogenate viscosity, since the release of intracellular polymers causes the reduction of the flow rate through the homogenizing narrow.[56]
Electrochemical determination of L-arginine in leukemic blood samples based on a polyaniline-multiwalled carbon nanotube—magnetite nanocomposite film modified glassy carbon electrode
Published in Instrumentation Science & Technology, 2020
Ashish Kumar Singh, Rajni Sharma, Minni Singh, Neelam Verma
The present work utilized this concept to a single enzymatic reaction to improve the overall selectivity of a biosensor toward arginine. The enzyme arginine deiminase (ADI) was partially purified from the Pseudomonas putida MTCC1313 bacteria and immobilized as the biorecognition element in multiwalled carbon nanotubes (MWCNT), iron oxide nanoparticles and a polyaniline (PANI) nanocomposite film which were electrochemically deposited on to the surface of glassy carbon electrode (GCE). Arginine deiminase hydrolyzes L-arginine to produce citrulline and NH3, thus leading to the reduction of the polyaniline film on the GCE surface. Many biosensors have been fabricated for L-arginine detection; however, the present approach is advantageous in terms of simplicity, real time analysis, selectivity, sensitive read-out and cost effectiveness. Furthermore, this is the first ever report to use the electrochemical biosensor for real sample (leukemic) analysis to the best of our knowledge.