1
|
Liu B, Wang H. Detection of N 6-Methyladenine in Eukaryotes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1280:83-95. [PMID: 33791976 DOI: 10.1007/978-3-030-51652-9_6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
DNA N6-methyladenine (6mA) is a chemical modification at the N6-positon of adenine. In the last decades, 6mA had been found in genome from numerous prokaryotic species, but only existed in a few lower eukaryotes. In prokaryotes, 6mA plays an important role in restriction-modification, DNA replication, and DNA mismatch repair. Because of the too low abundance of 6mA, it was long-stalled whether 6mA existed in multicellular eukaryotes and playing any functions, particularly in mammals. In recent years, partially benefitting from the advances in analytical methods, 6mA was found in the genomes from Drosophila melanogaster, Chlamydomonas algae, Caenorhabditis elegans, zebrafish, Xenopus laevis and mouse embryonic stem cells and even in the human genome. The 6mA was dynamic changed in early embryonic development of fly and zebrafish and much more enriched in gene body of transposons in fly, repetitive regions in zebrafish, around the transcription start sites in Chlamydomonas, and widespread distribution in C. elegans, indicating 6mA probably playing different functions in different species. Meanwhile, 6mA methylases and demethylases were found in fly, worm, and Chlamydomonas. In this chapter, we will briefly review the distribution, regulation, and function of 6mA in eukaryotes and focus on the advances of 6mA analysis methods, especially LC-MS/MS, immunoprecipitation, next-generation sequencing, and single-molecule real-time sequencing technology.
Collapse
Affiliation(s)
- Baodong Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Hailin Wang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China. .,University of Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
2
|
Liu B, Liu X, Lai W, Wang H. Metabolically Generated Stable Isotope-Labeled Deoxynucleoside Code for Tracing DNA N 6-Methyladenine in Human Cells. Anal Chem 2017; 89:6202-6209. [PMID: 28471639 DOI: 10.1021/acs.analchem.7b01152] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
DNA N6-methyl-2'-deoxyadenosine (6mdA) is an epigenetic modification in both eukaryotes and bacteria. Here we exploited stable isotope-labeled deoxynucleoside [15N5]-2'-deoxyadenosine ([15N5]-dA) as an initiation tracer and for the first time developed a metabolically differential tracing code for monitoring DNA 6mdA in human cells. We demonstrate that the initiation tracer [15N5]-dA undergoes a specific and efficient adenine deamination reaction leading to the loss the exocyclic amine 15N, and further utilizes the purine salvage pathway to generate mainly both [15N4]-dA and [15N4]-2'-deoxyguanosine ([15N4]-dG) in mammalian genomes. However, [15N5]-dA is largely retained in the genomes of mycoplasmas, which are often found in cultured cells and experimental animals. Consequently, the methylation of dA generates 6mdA with a consistent coding pattern, with a predominance of [15N4]-6mdA. Therefore, mammalian DNA 6mdA can be potentially discriminated from that generated by infecting mycoplasmas. Collectively, we show a promising approach for identification of authentic DNA 6mdA in human cells and determine if the human cells are contaminated with mycoplasmas.
Collapse
Affiliation(s)
- Baodong Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China.,University of Chinese Academy of Sciences , Beijing 100049, China
| | - Xiaoling Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China.,University of Chinese Academy of Sciences , Beijing 100049, China
| | - Weiyi Lai
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China.,University of Chinese Academy of Sciences , Beijing 100049, China
| | - Hailin Wang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China.,University of Chinese Academy of Sciences , Beijing 100049, China
| |
Collapse
|
3
|
|
4
|
Pollack JD, Williams MV, McElhaney RN. The comparative metabolism of the mollicutes (Mycoplasmas): the utility for taxonomic classification and the relationship of putative gene annotation and phylogeny to enzymatic function in the smallest free-living cells. Crit Rev Microbiol 1998; 23:269-354. [PMID: 9439886 DOI: 10.3109/10408419709115140] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mollicutes or mycoplasmas are a class of wall-less bacteria descended from low G + C% Gram-positive bacteria. Some are exceedingly small, about 0.2 micron in diameter, and are examples of the smallest free-living cells known. Their genomes are equally small; the smallest in Mycoplasma genitalium is sequenced and is 0.58 mb with 475 ORFs, compared with 4.639 mb and 4288 ORFs for Escherichia coli. Because of their size and apparently limited metabolic potential, Mollicutes are models for describing the minimal metabolism necessary to sustain independent life. Mollicutes have no cytochromes or the TCA cycle except for malate dehydrogenase activity. Some uniquely require cholesterol for growth, some require urea and some are anaerobic. They fix CO2 in anaplerotic or replenishing reactions. Some require pyrophosphate not ATP as an energy source for reactions, including the rate-limiting step of glycolysis: 6-phosphofructokinase. They scavenge for nucleic acid precursors and apparently do not synthesize pyrimidines or purines de novo. Some genera uniquely lack dUTPase activity and some species also lack uracil-DNA glycosylase. The absence of the latter two reactions that limit the incorporation of uracil or remove it from DNA may be related to the marked mutability of the Mollicutes and their tachytelic or rapid evolution. Approximately 150 cytoplasmic activities have been identified in these organisms, 225 to 250 are presumed to be present. About 100 of the core reactions are graphically linked in a metabolic map, including glycolysis, pentose phosphate pathway, arginine dihydrolase pathway, transamination, and purine, pyrimidine, and lipid metabolism. Reaction sequences or loci of particular importance are also described: phosphofructokinases, NADH oxidase, thioredoxin complex, deoxyribose-5-phosphate aldolase, and lactate, malate, and glutamate dehydrogenases. Enzymatic activities of the Mollicutes are grouped according to metabolic similarities that are taxonomically discriminating. The arrangements attempt to follow phylogenetic relationships. The relationships of putative gene assignments and enzymatic function in My. genitalium, My. pneumoniae, and My. capricolum subsp. capricolum are specially analyzed. The data are arranged in four tables. One associates gene annotations with congruent reports of the enzymatic activity in these same Mollicutes, and hence confirms the annotations. Another associates putative annotations with reports of the enzyme activity but from different Mollicutes. A third identifies the discrepancies represented by those enzymatic activities found in Mollicutes with sequenced genomes but without any similarly annotated ORF. This suggests that the gene sequence is significantly different from those already deposited in the databanks and putatively annotated with the same function. Another comparison lists those enzymatic activities that are both undetected in Mollicutes and not associated with any ORF. Evidence is presented supporting the theory that there are relatively small gene sequences that code for functional centers of multiple enzymatic activity. This property is seemingly advantageous for an organism with a small genome and perhaps under some coding restraint. The data suggest that a concept of "remnant" or "useless genes" or "useless enzymes" should be considered when examining the relationship of gene annotation and enzymatic function. It also suggests that genes in addition to representing what cells are doing or what they may do, may also identify what they once might have done and may never do again.
Collapse
Affiliation(s)
- J D Pollack
- Department of Medical Microbiology and Immunology, Ohio State University, Columbus 43210, USA.
| | | | | |
Collapse
|
5
|
Bonissol C, Sasaki T, Stoiljkovic B. Assay for detection of adenosine phosphorylase from mycoplasmas. ANNALES DE L'INSTITUT PASTEUR. MICROBIOLOGY 1988; 139:703-15. [PMID: 3150941 DOI: 10.1016/0769-2609(88)90075-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A microtechnique is described which permits simple evaluation of the activity of the enzyme adenosine phosphorylase (AdoP), present in all mycoplasmas tested thus far. The good solubility and stability of AdoP and the sensitivity of the assay should be advantageous in detecting mycoplasmas in biological samples such as animal sera, cell cultures and vaccines.
Collapse
Affiliation(s)
- C Bonissol
- Laboratoire des Mycoplasmes, Institut Pasteur, Paris
| | | | | |
Collapse
|
6
|
Zittoun J, Fischer A, Marquet J, Pérignon JL, Lagrue A, Griscelli C. Megaloblastic anemia and immune abnormalities in a patient with methionine synthase deficiency. Acta Paediatr 1987; 76:991-8. [PMID: 3425320 PMCID: PMC7159520 DOI: 10.1111/j.1651-2227.1987.tb17284.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/18/1987] [Indexed: 01/05/2023]
Abstract
We report a case of methionine synthase deficiency associated with cellular immune deficiency discovered in a 14-year-old boy. Principal findings were: developmental delay, recurrent upper and lower respiratory tract infections, megaloblastic anemia, discovered at 3 months of age, unresponsive to cyanocobalamin and poorly responsive to folinic acid. Biochemical studies showed: an abnormal deoxyuridine suppression test despite normal serum folate, cobalamin and transcobalamin levels; a normal intracellular uptake of these two coenzymes; and an absolute requirement of methionine for fibroblast growth, suggestive of defective methionine synthesis. An absence of methionine synthase activity in the patient's bone marrow and a profound depression of this activity in lymphocytes and liver were found. Hypergammaglobulinemia with variable lymphopenia, depressed lymphocyte transformation after lectin or recall-antigen stimulation, defective delayed-type hypersensitivity and decreased natural killer activity were noted as well. The patient died at the age of 14.
Collapse
Affiliation(s)
- J Zittoun
- Laboratoire Central d'Hématologie-Immunologie, Hôpital Henri Mondor, Creteil
| | | | | | | | | | | |
Collapse
|
7
|
Featherstone T, Marshall PD, Evans HJ. Problems and pitfalls in assessing human T-lymphocyte mutant frequencies. Mutat Res 1987; 179:215-30. [PMID: 3497342 DOI: 10.1016/0027-5107(87)90312-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The measurement of 6-thioguanine-resistant frequencies in human T-lymphocytes has been used to quantitate the in vivo HPRT mutant frequency. The data so far indicate a large variability in normal healthy individuals. The reliability with which wells are identified for clonal growth in the assay was investigated using 5 different methods of scoring: visual scoring, uptake of [3H]thymidine (either by cut off point or by statistical analysis), cell count and cytogenetic analysis. None of these methods presented a viable means of scoring the assay. An examination of the statistical precision of the assay under the limitations imposed by the experimental conditions leads to the conclusion that there is a large inherent error associated with the estimated mutant frequencies. Analysis of the T-lymphocyte subpopulations by cell surface monoclonal antibodies also leads us to believe that the observed mutant frequencies may not be representative of the true in vivo mutant frequencies. If the assay is to be used as a sensitive screen for individual or population exposure to possible mutagens, a closer understanding of the biology of the assay is indicated, and a comprehensive reevaluation of the methodology required. The utility of the system for studying qualitative aspects of human mutagenesis is not in doubt.
Collapse
|
8
|
McElwain MC, Pollack JD. Synthesis of deoxyribomononucleotides in Mollicutes: dependence on deoxyribose-1-phosphate and PPi. J Bacteriol 1987; 169:3647-53. [PMID: 3038846 PMCID: PMC212445 DOI: 10.1128/jb.169.8.3647-3653.1987] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Cell extracts of Acholeplasma laidlawii B-PG9, Acholeplasma morum S2, Mycoplasma capricolum 14, and Mycoplasma gallisepticum S6 were examined for 37 cytoplasmic enzyme activities involved in the salvage and biosynthesis of purines. All of these organisms had adenine phosphoribosyltransferase activity (EC 2.4.2.7) and hypoxanthine phosphoribosyltransferase activity (EC 2.4.2.8). All of these organisms had purine-nucleoside phosphorylase activity (EC 2.4.2.1) in the synthetic direction using ribose-1-phosphate (R-1-P) or deoxyribose-1-phosphate (dR-1-P); this activity generated ribonucleosides or deoxyribonucleosides, respectively. The pyrimidine nucleobase uracil could also be ribosylated by using either R-1-P or dR-1-P as a donor. The synthesis of deoxyribonucleosides from nucleobases and dR-1-P has been reported from only one other procaryote, Escherichia coli (L. A. Mason and J. O. Lampen, J. Biol. Chem. 193:539-547, 1951). The reverse of this phosphorylase reaction is more widely known, and we found such activity in all mollicutes studied. Some Acholeplasma species but not the Mycoplasma species can phosphorylate deoxyribonucleosides to deoxyribomononucleotides by a PPi-dependent deoxyribonucleoside kinase activity, which was first reported in this group for the ribose analogs (V. V. Tryon and J. D. Pollack, Int. J. Syst. Bacteriol. 35:497-501, 1985). This is the first report of PPi-dependent purine deoxyribonucleoside kinase activity. An ATP-dependent purine deoxyribonucleoside kinase activity is known only in salmon milt extracts (H. L. A. Tarr, Can. J. Biochem. 42:1535-1545, 1964). Deoxyribomononucleotidase activity was also found in cytoplasmic extracts of these mollicutes. This is the first report of deoxyribomononucleotidase activity.
Collapse
|
9
|
Pérignon JL, Bories DM, Houllier AM, Thuillier L, Cartier PH. Metabolism of pyrimidine bases and nucleosides by pyrimidine-nucleoside phosphorylases in cultured human lymphoid cells. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 928:130-6. [PMID: 3567226 DOI: 10.1016/0167-4889(87)90113-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The anabolism of pyrimidine ribo- and deoxyribonucleosides from uracil and thymine was investigated in phytohemagglutinin-stimulated human peripheral blood lymphocytes and in a Burkitt's lymphoma-derived cell line (Raji). We studied the ability of these cells to synthesize pyrimidine nucleosides by ribo- and deoxyribosyl transfer between pyrimidine bases or nucleosides and the purine nucleosides inosine and deoxyinosine as donors of ribose 1-phosphate and deoxyribose 1-phosphate, respectively: these reactions involve the activities of purine-nucleoside phosphorylase, and of the two pyrimidine-nucleoside phosphorylases (uridine phosphorylase and thymidine phosphorylase). The ability of the cells to synthesize uridine was estimated from their ability to grow on uridine precursors in the presence of an inhibitor of pyrimidine de novo synthesis (pyrazofurin). Their ability to synthesize thymidine and deoxyuridine was estimated from the inhibition of the incorporation of radiolabelled thymidine in cells cultured in the presence of unlabelled precursors. In addition to these studies on intact cells, we determined the activities of purine- and pyrimidine-nucleoside phosphorylases in cell extracts. Our results show that Raji cells efficiently metabolize preformed uridine, deoxyuridine and thymidine, are unable to salvage pyrimidine bases, and possess a low uridine phosphorylase activity and markedly decreased (about 1% of peripheral blood lymphocytes) thymidine phosphorylase activity. Lymphocytes have higher pyrimidine-nucleoside phosphorylases activities, they can synthesize deoxyuridine and thymidine from bases, but at high an non-physiological concentrations of precursors. Neither type of cell is able to salvage uracil into uridine. These results suggest that pyrimidine-nucleoside phosphorylases have a catabolic, rather than an anabolic, role in human lymphoid cells. The facts that, compared to peripheral blood lymphocytes, lymphoblasts possess decreased pyrimidine-nucleoside phosphorylases activities, and, on the other hand, more efficiently salvage pyrimidine nucleosides, are consistent with a greater need of these rapidly proliferating cells for pyrimidine nucleotides.
Collapse
|
10
|
Induction of adenine salvage in mouse cell lines deficient in adenine phosphoribosyltransferase. Mol Cell Biol 1986. [PMID: 3837181 DOI: 10.1128/mcb.5.10.2662] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Adenine phosphoribosyltransferase (APRT) (EC 2.4.2.7) pseudorevertant cell lines were isolated under selective conditions requiring adenine salvage for survival; yet they were found to be deficient in measurable APRT activity and resistant to the purine analog 2'6'-diaminopurine (DAP) (M.S. Turker, J. A. Tischfield, P. Rabinovitch, P.J. Stambrook, J.J. Trill, A.C. Smith, C.E. Ogburn, and G.M. Martin, manuscript in preparation). Adenine salvage was examined in two APRT pseudorevertant cell lines, their two APRT homozygous deficient parental cell lines, and a genotypic APRT revertant cell line (i.e., one with measurable APRT activity and DAP sensitivity). Adenine accumulation was observed in both revertant phenotypes and was demonstrated by high-performance liquid chromatography to be linked with adenine metabolism. The ability to salvage adenine declined substantially in the pseudorevertant cell lines when they were removed from selective media containing inhibitors of de novo 5'-AMP synthesis (alanosine and azaserine); for one pseudorevertant cell line this decline was accelerated by the addition of DAP to the medium. The readdition of alanosine or azaserine to the growth medium of the pseudorevertant lines induced adenine salvage to its previous levels. An APRT-like cross-reacting material was found in the pseudorevertant cell lines, although its relationship to adenine salvage is unknown. A low level of constitutive adenine salvage was found in the parental APRT-deficient lines, and it was also possible to induce adenine salvage in these cell lines. These findings suggest a novel regulatory mechanism for adenine salvage.
Collapse
|
11
|
Buc HA, Thuillier L, Hamet M, Garreau F, Moncion A, Pérignon JL. Energy metabolism in adenosine deaminase-inhibited human erythrocytes. Clin Chim Acta 1986; 156:61-9. [PMID: 3486057 DOI: 10.1016/0009-8981(86)90179-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The metabolic changes induced by the deoxycoformycin inhibition of adenosine deaminase were studied in human erythrocytes incubated with nucleosides. 1 Adenosine nucleotide levels and glycolytic rate were increased by adenosine. 2 With deoxyadenosine, the cellular ATP level was reduced when dATP increased and the glycolytic rate was similarly enhanced. 3 The hypoxanthine production was equivalent in both cases. Our data demonstrate that human red cells are able to catabolize adenine deoxynucleotides into hypoxanthine, and the control of energy metabolism is not impaired by adenosine deaminase inhibition when PO identical to 4 and NAD+ are not limiting.
Collapse
|
12
|
Pérignon JL, Thuillier L, Hamet M, Houllier AM, Cartier PH. Synergistic toxicity of pyrazofurin and cytidine in cytidine deaminase deficient lymphoid cells (Raji). INTERNATIONAL JOURNAL OF IMMUNOPHARMACOLOGY 1986; 8:427-31. [PMID: 3744641 DOI: 10.1016/0192-0561(86)90127-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The intermediary metabolism of pyrimidine nucleosides was studied in a line of human B lymphoblasts (Raji) in which pyrimidine de novo synthesis deficiency was pharmacologically induced by pyrazofurin. It was found that Raji cells are cytidine deaminase deficient that cytidine has a synergistic effect on the toxicity of pyrazofurin towards these cytidine deaminase deficient cells, affecting both the proliferation and the viability of the cells. Indirect evidences suggest that this synergistic toxicity is not mediated by an effect on nucleoside diphosphate reductase nor on the first steps of pyrimidine de novo synthesis.
Collapse
|
13
|
Pérignon JL, Le Deist F, Arenzana-Seisdedos F, Thuillier L, Fischer A, Cartier P, Griscelli C. Cytidine deaminase deficiency in a child with combined immunodeficiency: more than a coincidence? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1986; 195 Pt A:129-35. [PMID: 2425563 DOI: 10.1007/978-1-4684-5104-7_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
14
|
Turker MS, Martin GM. Induction of adenine salvage in mouse cell lines deficient in adenine phosphoribosyltransferase. Mol Cell Biol 1985; 5:2662-8. [PMID: 3837181 PMCID: PMC367003 DOI: 10.1128/mcb.5.10.2662-2668.1985] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Adenine phosphoribosyltransferase (APRT) (EC 2.4.2.7) pseudorevertant cell lines were isolated under selective conditions requiring adenine salvage for survival; yet they were found to be deficient in measurable APRT activity and resistant to the purine analog 2'6'-diaminopurine (DAP) (M.S. Turker, J. A. Tischfield, P. Rabinovitch, P.J. Stambrook, J.J. Trill, A.C. Smith, C.E. Ogburn, and G.M. Martin, manuscript in preparation). Adenine salvage was examined in two APRT pseudorevertant cell lines, their two APRT homozygous deficient parental cell lines, and a genotypic APRT revertant cell line (i.e., one with measurable APRT activity and DAP sensitivity). Adenine accumulation was observed in both revertant phenotypes and was demonstrated by high-performance liquid chromatography to be linked with adenine metabolism. The ability to salvage adenine declined substantially in the pseudorevertant cell lines when they were removed from selective media containing inhibitors of de novo 5'-AMP synthesis (alanosine and azaserine); for one pseudorevertant cell line this decline was accelerated by the addition of DAP to the medium. The readdition of alanosine or azaserine to the growth medium of the pseudorevertant lines induced adenine salvage to its previous levels. An APRT-like cross-reacting material was found in the pseudorevertant cell lines, although its relationship to adenine salvage is unknown. A low level of constitutive adenine salvage was found in the parental APRT-deficient lines, and it was also possible to induce adenine salvage in these cell lines. These findings suggest a novel regulatory mechanism for adenine salvage.
Collapse
|
15
|
Pérignon JL, Chaléon J, Leverger G, Houllier AM, Thuillier L, Cartier PH. Cytidine deaminase activity of human normal and malignant lymphoid cells. Clin Chim Acta 1985; 147:67-74. [PMID: 3872745 DOI: 10.1016/0009-8981(85)90066-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Cytidine deaminase activity was determined by a radioisotopic assay in extracts of peripheral blood mononuclear cells of normal individuals and of patients with acute lymphoblastic leukaemia. The normal enzyme activity had a broad pH optimum between pH 6.5 and 8.0; apparent Km values for cytidine and deoxycytidine were 3.6 +/- 0.6 mumol/l and 26.5 +/- 3.5 mumol/l, respectively; the activity was resistant to heat inactivation; of the various effectors tested, only uridine, deoxyuridine and tetrahydroxyuridine had inhibitory effects. Cytidine deaminase activity was markedly decreased in lymphoblasts of patients with acute lymphoblastic leukaemia; enzyme activity was related to the percentage of circulating blast cells, and not to the clinical, cytological or immunological characters of the leukaemia.
Collapse
|
16
|
|
17
|
Sinigaglia F, Scheidegger D, Talmadge K, Garotta G. A sensitive and quantitative microassay for the detection of mycoplasma contamination: inhibition of IL-2 dependent cell line proliferation. J Immunol Methods 1985; 76:85-92. [PMID: 3871462 DOI: 10.1016/0022-1759(85)90483-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A simple, rapid and sensitive microassay for mycoplasma detection in cell culture is reported. The assay is based on the fact that culture supernatants from contaminated cells inhibit [3H]thymidine incorporation by an IL-2 dependent mouse cytotoxic T cell line (CTLL). The mechanism of inhibition is related to the production by several mycoplasma strains of a pyrimidine-specific nucleoside phosphorylase which can degrade the radiolabelled thymidine used for the measurement of DNA synthesis. These strains were the commonest contaminants in cultures of 24 cell lines from 5 different sources. To establish the sensitivity of the test to detect mycoplasmas we have also used the inhibition assay to monitor the clearance of mycoplasma from 2 contaminated cell lines.
Collapse
|
18
|
Nelson PV, Carey WF. A method for enrichment of hybrid somatic cells: complementation studies in certain lysosomal enzymopathies. J Inherit Metab Dis 1985; 8:95-9. [PMID: 3939596 DOI: 10.1007/bf01819286] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
An improved method, which combined a number of published techniques, is described for the polyethylene-glycol-induced fusion of mononuclear human skin fibroblasts in the presence of phytohaemagglutinin-P and for the subsequent isolation of polynuclear cells by Ficoll gradient sedimentation. Enriched cultures contain between 60 and 75% multinucleated cells and may be maintained in culture without fetal calf serum for up to 14 days without significant overgrowth by the few contaminating mononuclear parental cells. Complementation appears not to occur between GM1 gangliosidosis and mucopolysaccharidosis, type VI B (Morquio) cell strains; this experimental observation provides support for the earlier hypothesis that the mutations for these conditions are allelic. Earlier observations that complementation does not occur between selected phenotypic variants (viz., neuronopathic forms and those without neurological involvement) of sphingomyelin storage (Niemann-Pick) disease or Gaucher's disease are confirmed.
Collapse
|
19
|
Tryon VV, Pollack D. Purine metabolism in Acholeplasma laidlawii B: novel PPi-dependent nucleoside kinase activity. J Bacteriol 1984; 159:265-70. [PMID: 6330034 PMCID: PMC215623 DOI: 10.1128/jb.159.1.265-270.1984] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Acholeplasma laidlawii B-PG9 was examined for 16 cytoplasmic enzymes with activity for purine salvage and interconversion. Phosphoribosyltransferase activities for adenine, guanine, xanthine, and hypoxanthine were shown. Adenine, guanine, xanthine, and hypoxanthine were ribosylated to their nucleoside. Adenosine, inosine, xanthosine, and guanosine were converted to their base. No ATP-dependent phosphorylation of nucleosides to mononucleotides was found. However, PPi-dependent phosphorylation of adenosine, inosine, and guanosine to AMP, inosine monophosphate, and GMP, respectively, was detected. Nucleotidase activity for AMP, inosine monophosphate, xanthosine monophosphate, and GMP was also found. Interconversion of GMP to AMP was detected. Enzyme activities for the interconversion of AMP to GMP were not detected. Therefore, A. laidlawii B-PG9 cannot synthesize guanylates from adenylates or inosinates. De novo synthesis of purines was not detected. This study demonstrates that A. laidlawii B-PG9 has the enzyme activities for the salvage and limited interconversion of purines and, except for purine nucleoside kinase activity, is similar to Mycoplasma mycoides subsp. mycoides. This is the first report of a PPi-dependent nucleoside kinase activity in any organism.
Collapse
|
20
|
Chaléon J, Pérignon JL, Hamet M, Cartier PH. S-adenosylhomocysteine hydrolase activity in defects of enzymes of purine metabolism and inhibition by various purine compounds. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1984; 165 Pt B:71-4. [PMID: 6720453 DOI: 10.1007/978-1-4757-0390-0_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
21
|
Bonissol C, Traincard F, Stoïljkovic B, Hosli P. Adenosine phosphorylase activity as a technique for detection of mycoplasmas in biological media. ANNALES DE MICROBIOLOGIE 1984; 135A:63-72. [PMID: 6424528 DOI: 10.1016/s0769-2609(84)80060-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The importance of cell culture contamination by mycoplasmas is well recognized, but the means used to detect such contamination still need improvement. Most mycoplasmas possess an enzyme, adenosine phosphorylase, which is not found in cell lines. We used the ultramicromethod of Uitendaal et al. to detect the presence of mycoplasmas in sera and in tissue culture medium. The absence of adenosine phosphorylase activity seems to be the best guarantee that a serum is not contaminated by mycoplasmas. This test is also most efficient for the detection of mycoplasmas in tissue or cell cultures in vitro.
Collapse
|
22
|
McGarrity GJ, Vanaman V, Sarama J. Cytogenetic effects of mycoplasmal infection of cell cultures: a review. IN VITRO 1984; 20:1-18. [PMID: 6199287 DOI: 10.1007/bf02633326] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
23
|
Verhoef V, Germain G, Fridland A. Adenosine phosphorylase activity in mycoplasma-free growth media for mammalian cells. Exp Cell Res 1983; 149:37-44. [PMID: 6416875 DOI: 10.1016/0014-4827(83)90378-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Mammalian cells have enzymes that deaminate adenosine to inosine, which can readily be phosphorolysed to hypoxanthine. They do not, however, possess enzymes to form adenine by the cleavage of adenosine. For this reason, the release of adenine from adenosine by mammalian cell cultures has usually been interpreted as indicating the presence of mycoplasma, a frequent microbial contaminant that contains high levels of adenosine phosphorylase. We found that some human lymphoblast cultures free of mycoplasma showed high levels of adenosine cleavage and that this activity resulted from adenosine phosphorylase in the bovine serum used as the culture growth supplement. A survey of 13 serum supplements disclosed that fetal bovine serum (six lots) contains the highest adenosine phosphorylase activity, ranging from 9 to 648 nmol adenine produced per hour per ml serum; newborn calf serum (four lots) has much less activity, ranging from 0 to 5 nmol adenine produced per hour per ml serum; and donor horse serum (three lots) contains no detectable activity. These results suggest that mycoplasma tests dependent on the presence of adenosine phosphorylase or other enzyme activities may give false-positives with cultures containing fetal bovine serum supplements.
Collapse
|
24
|
McIvor RS, Wohlhueter RM, Plagemann PG. Uracil phosphoribosyltransferase from Acholeplasma laidlawii: partial purification and kinetic properties. J Bacteriol 1983; 156:192-7. [PMID: 6619094 PMCID: PMC215069 DOI: 10.1128/jb.156.1.192-197.1983] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Uracil phosphoribosyltransferase was purified 34-fold from sonicated extracts of Acholeplasma laidlawii by ammonium sulfate precipitation, binding to DEAE-Sephadex, Sephadex G-200 chromatography, and hydroxylapatite chromatography. The molecular weight of the enzyme by gel filtration was approximately 80,000. The pH optimum for phosphoribosylation was around 7.5, and the optimum MgCl2 concentration was 5 mM. Initial velocity studies were conducted over a wide range of both uracil and 5-phosphoribosyl-1-pyrophosphate (P-Rib-PP) concentrations, and various equations for biomolecular reaction mechanisms were fitted to the data by nonlinear regression. When the equation for an ordered sequential mechanism was fitted to the data, the Kia thus obtained was not statistically different from zero. This is interpreted as evidence for a nonsequential ("ping-pong") reaction. Graphic analysis of the data by the Hanes-Woolf linear transform supported this conclusion. The enzyme has high affinity for uracil (KmUra = 4.2 microM; KmP-Rib-PP = 66 microM), which provides supporting evidence that this activity is responsible for the incorporation of uracil and uridine into nucleotides.
Collapse
|
25
|
McIvor RS, Wohlhueter RM, Plagemann PG. Uridine phosphorylase from Acholeplasma laidlawii: purification and kinetic properties. J Bacteriol 1983; 156:198-204. [PMID: 6619095 PMCID: PMC215070 DOI: 10.1128/jb.156.1.198-204.1983] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Uridine phosphorylase was purified 1,370-fold from sonicated extracts of Acholeplasma laidlawii by ammonium sulfate precipitation, DEAE-Sephadex column chromatography, hydroxylapatite chromatography, and Sephadex G-200 fractionation. The molecular weight of the enzyme as determined by gel filtration was approximately 65,000. [U-14C]ribose-1-phosphate (Rib-1-P), prepared enzymatically from [U-14C]inosine, was utilized in initial velocity studies of uridine synthesis, which indicated a sequential reaction with a KmUra of 110 microM and a KmRib-1-P of 17 microM. The kinetics of uridine cleavage were assessed at a saturating cosubstrate concentration, resulting in a KmUrd of 170 microM and a KmPi of 120 microM. These results indicate that an intracellular flux from uracil to uridine is kinetically feasible. However, such flux would be metabolically unproductive, since the low affinity of uridine kinase (KmUrd = 3.2 mM) precludes the operation of uridine phosphorylase and uridine kinase in tandem to convert uracil to UMP. We conclude that uridine phosphorylase performs only a catabolic function in A. laidlawii.
Collapse
|
26
|
Pérignon JL, Houllier AM, Cartier PH. A facile radio-isotopic assay for phosphoribomutase activity in human red blood cells. Clin Chim Acta 1983; 129:365-70. [PMID: 6303632 DOI: 10.1016/0009-8981(83)90041-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
27
|
Girot R, Hamet M, Perignon JL, Guesnu M, Fox RM, Cartier P, Durandy A, Griscelli C. Cellular immune deficiency in two siblings with hereditary orotic aciduria. N Engl J Med 1983; 308:700-4. [PMID: 6828110 DOI: 10.1056/nejm198303243081207] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
28
|
Upchurch S, Gabridge MG. De novo purine synthesis, purine salvage, and DNA synthesis in normal and Lesch-Nyhan fibroblasts infected with Mycoplasma pneumoniae. Infect Immun 1983; 39:164-71. [PMID: 6401690 PMCID: PMC347920 DOI: 10.1128/iai.39.1.164-171.1983] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The effects of Mycoplasma pneumoniae on host cell metabolism were studied by using two types of host cells, MRC-5 human lung fibroblasts, a normal cell line, and Lesch-Nyhan fibroblasts, a cell line deficient in hypoxanthine-guanine phosphoribosyl transferase (EC 2.4.2.8). The susceptibilities of the two cell types were determined by infecting the cells with M. pneumoniae at different multiplicities of infection (MOI). Our data indicate that the Lesch-Nyhan cells were four times more susceptible to damage by M. pneumoniae than the MRC-5 cells. The effects of different MOIs (10 and 50) on de novo purine synthesis. DNA synthesis, and the development of a cytopathic effect were determined. In both cell types, the higher MOI inhibited de novo purine synthesis to a greater extent than the lower MOI. This correlated closely with the cytopathic effect which developed in the monolayers (i.e., the more the inhibition of de novo purine synthesis, the greater the cytopathic effect which developed). In the Lesch-Nyhan cells, DNA synthesis was completely inhibited by the high MOI, whereas in the MRC-5 cells, DNA synthesis was stimulated by the high MOI. In the MRC-5 cells infected with M. pneumoniae, purine salvage activity increased, as indicated by an increase in adenosine deaminase (EC 3.5.4.4) activity. These data indicate that M. pneumoniae alters host cell metabolism, particularly the nucleic acid metabolic pathways. This may explain in part the mechanism of pathogenesis of M. pneumoniae infection.
Collapse
|
29
|
Pérignon JL, Hamet M, Buc HA, Cartier PH, Derycke M. Biochemical study of a case of hemolytic anemia with increased (85 fold) red cell adenosine deaminase. Clin Chim Acta 1982; 124:205-12. [PMID: 7139940 DOI: 10.1016/0009-8981(82)90388-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
An increased red cell adenosine deaminase (ADA) activity (85-fold) was found in a 10-year-old male child suffering from severe hemolytic disease. Evidence is given that the excessive ADA activity in erythrocytes is due to an abnormal amount of a catalytically and immunologically normal enzyme. Metabolic studies with the patient's erythrocytes show that the low ATP concentration in these cells (64% of comparably reticulocyte-rich blood) is due both to a diminished synthesis of adenylic nucleotides from adenosine, and to an excessive catabolism of AMP.
Collapse
|
30
|
Cassingena R, Ermonval M, Kay A, Nardeux P, Persuy MA, Suarez HG, Fellous M, Bonissol C. Surface markers on mouse cells transformed after exposure to HeLa chromosomes are Mycoplasma membrane proteins. ANNALES D'IMMUNOLOGIE 1982; 133C:309-23. [PMID: 6756281 DOI: 10.1016/0769-2625(82)90044-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Antisera were raised against HeLa cells and mouse cells transformed after exposure to HeLa chromosomes (ME-ch.HeLa). The antisera were positive in indirect immunofluorescence assays on both HeLa and ME-ch.HeLa cells, but were negative on normal mouse cells. Immunoprecipitation of 125I-labelled cell extracts showed that Me-ch.HeLa cells contain at their surface 3 proteins of apparent molecular weights of 185,000, 105,000 and 45,000 daltons, which were also present on the surface of our HeLa cells but not on other mouse cell lines tested. However, further study has shown that these proteins are not normal constituents of HeLa plasma membranes but are in fact surface proteins of Mycoplasma orale.
Collapse
|
31
|
Marsac C, Augereau C, Feldman G, Wolf B, Hansen TL, Berger R. Prenatal diagnosis of pyruvate carboxylase deficiency. Clin Chim Acta 1982; 119:121-7. [PMID: 6800673 DOI: 10.1016/0009-8981(82)90412-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
32
|
McGarrity GJ. Detection of Mycoplasmal Infection of Cell Cultures. ACTA ACUST UNITED AC 1982. [DOI: 10.1016/b978-0-12-007902-5.50009-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
|
33
|
Steiner T, McGarrity GJ, Phillips DM. Cultivation and partial characterization of spiroplasmas in cell cultures. Infect Immun 1982; 35:296-304. [PMID: 6797950 PMCID: PMC351029 DOI: 10.1128/iai.35.1.296-304.1982] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Spiroplasmas were propagated in the Drosophila melanogaster cell line Dm-1. Spiroplasma citri and unidentified strains (corn shunt organism, 277F [tick isolate], powder puff, BNR-1, honey bee, and OBMG) grew to 10(8) to 10(9) colony-forming units per ml and could be passaged. Cytopathic effect (CPE) varied with the infecting spiroplasma. The honey bee isolate killed Dm-1 within 2 to 4 days and produced CPE in four mammalian cells tested. At 25 degrees C, suckling mouse cataract agent produced no CPE in Dm-1 cells. Dm-1 cells did not support growth of the spiroplasmal sex ratio organism. Spiroplasmas could be detected in the cell cultures by agar inoculation, dark-field microscopy, scanning electron microscopy, and DNA fluorescent staining. The uridine phosphorylase test showed significant levels of conversion of [14C]uridine to [14C]uracil for all but some plant isolates: S. citri, corn shunt organism, lettuce, cactus, and powder puff strains, the first mycoplasmas to lack the enzyme. Primary isolations of corn shunt organism from infected corn plants were made in Dm-1 and I-XII cultures. The course of corn stunt organism infection of Dm-1 was monitored for three passages. The use of agarose and Dienes staining of the colonies improved growth and colony counting of corn stunt organism. The number of viable infected DM-1 cells decreased from 1.2 x 10(7) at passage 1 to 7.0 x 10(6) at passage 2 and 3 x 10(5) at passage 3.
Collapse
|