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Genetic analysis of nitrate reductase-deficient mutants in Chlamydomonas reinhardii

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Summary

Six mutants (305, 301, 203, 307, 104 and 102) of Chlamydomonas reinhardii, all defective in nitrate reductase (NR) activity, have been genetically analyzed. All except 102 carry single Mendelian mutations.

Mutant 305, defective in diaphorase activity and mutant 301, defective in terminal enzyme activity, did not give rise to wild-type recombinants when crossed to each other or with the nit-1 mutant isolated from strain 137c (which is actually a double mutant nit-1 nit-2). Nit-1 was shown to lack both diaphorase and terminal activities. Whether the mutated sites in 305 and 301 are located in a unique cistron (nit-1) or in two adjacent cistrons (nit-1a and nit-1b) coding for a diaphorase subunit and a terminal subunit of NR is discussed in the light of previous biochemical findings.

The 203 mutation affecting a regulatory gene did not recombine with nit-2, the other mutated locus present in strain 137c.

Mutants 307, 104 and 102, all lacking molybdenum cofactor for both NR and xanthine dehydrogenase, where shown to be affected in different loci. The genes mutated in 307 and 104 have been designated nit-3 and nit-4, respectively. The 102 strain is mutated in two non-linked loci, nit-5 and nit-6, with both mutations required to confer the mutant phenotype. One of these cryptic mutations is present in the “wild” strain 21gr.

The results indicate that at least six or seven loci are involved in the production of an active NR enzyme: one (nit-1) or two (nit-1a and nit-1b) cistrons to produce the NR apoproteins responsible for the partial activities diaphorase and terminal, one locus (nit-2) for the regulation of NR synthesis, and four loci (nit-3, nit-4, nit-5 and nit-6) to produce the molybdenum cofactor. The loci nit-1a and nit-2 seem to correspond to the nit-A and nit-B loci described by Nichols and Syrett (J Gen Microbiol 108:71–77, 1978).

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Abbreviations

NR:

nitrate reductase

MNNG:

N-methyl-N′-nitro-N-nitrosoguanidine

MoCo:

molybdenum-containing cofactor

PD:

parental ditype

NPD:

non-parental ditype

TT:

tetratype

WT:

wild type

BVH:

reduced benzyl viologen

References

  1. Bachmann BJ (1983) Microbiol Rev 47:180–230

  2. Barea JL, Cárdenas J (1975) Arch Microbiol 105:21–25

  3. Cove DJ (1979) Biol Rev 54:291–327

  4. Fernández E, Cárdenas J (1981a) Biochim Biophys Acta 657:1–12

  5. Fernández E, Cárdenas J (1981b) Planta 153:254–257

  6. Fernández E, Cárdenas J (1982a) Biochim Biophys Acta 681:530–537

  7. Fernández E, Cárdenas J (1982b) Mol Gen Genet 186:164–169

  8. Fernández E, Cárdenas J (1983a) Biochim Biophys Acta 745:12–19

  9. Fernández E, Cárdenas J (1983b) Z Naturforsch 38:439–445

  10. Franco AR, Cárdenas J, Fernández E (1984) EMBO J 3:1403–1407

  11. Garrett RH, Amy NK (1978) Microbial Physiol 18:1–65

  12. Giles NH (1978) Am Natur 112:641–657

  13. Gorman DS, Levine RP (1965) Proc Natl Acad Sci (Wash) 54:1665–1669

  14. Guerrero MG, Vega JM, Losada M (1981) Ann Rev Plant Physiol 32:169–204

  15. Hewitt EJ, Notton BA (1980) Nitrate reductase systems in eukaryotic and prokaryotic organisms. In: Coughlan MP (ed) Molybdenum and molybdenum-containing enzymes. Pergamon Press Ltd, Oxford, pp 273–325

  16. Howard WD, Solomonson LP (1982) J Biol Chem 257:10243–10250

  17. Johnson JL (1980) The molybdenum cofactor common to nitrate reductase, xanthine dehydrogenase and sulfite oxidase. In: Coughlan MP (ed) Molybdenum and molybdenum-containing enzymes. Pergamon Press Ltd, Oxford, pp 345–383

  18. Johnson JL, Rajagopalan KV (1982) Proc Natl Acad Sci USA 79:6856–6860

  19. Jones EW, Fink GR (1982) Regulation of amino acid and nucleotide biosynthesis in yeast. In: Stathern JN, Jones EW, Broad JR (eds) The molecular biology of the yeast Saccharomyces. Metabolism and gene expression. Cold Spring Harbor Series, pp 181–299

  20. Kleinhofs A, Taylor J, Kuo TM, Somers DA, Warner RL (1983) Nitrate reductase genes as selectable markers for plant cell transformation. In: Lurquin PF, Kleinhofs A (eds) Genetic engineering in eukaryotes. Plenum Publishing Co, New York, pp 215–231

  21. Levine RP, Ebersold WT (1960) Ann Rev Microbiol 14:197–216

  22. Loppes R (1966) Z Vererb Lehre 98:193–202

  23. Marzluf GA (1981) Microbiol Rev 45:437–461

  24. Mendel RR, Müller AJ (1979) Mol Gen Genet 177:145–153

  25. Mendel RR, Müller AJ (1980) Plant Sci Lett 18:277–288

  26. Nichols GL, Syrett PJ (1978) J Gen Microbiol 108:71–77

  27. Nichols GL, Shehata SAM, Syrett PJ (1978) J Gen Microbiol 108:79–88

  28. Pan SS, Nason A (1978) Biochim Biophys Acta 523:279–313

  29. Smyth RD, Martinek GW, Ebersold WT (1975) J Bacteriol 124:1615–1617

  30. Sosa FM, Ortega T, Barea JL (1978) Plant Sci Lett 11:51–58

  31. Tomsett AB, Garrett RH (1980) Genetics 65:649–660

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Correspondence to René F. Matagne.

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Fernández, E., Matagne, R.F. Genetic analysis of nitrate reductase-deficient mutants in Chlamydomonas reinhardii . Curr Genet 8, 635–640 (1984). https://doi.org/10.1007/BF00395710

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Key words

  • Chlamydomonas reinhardii
  • Nitrate reductase