paranemicadj.

1941 A. H. Sparrow et al. in Canad. Jrnl. Res. C. 19 325 Kuwada..describes two types of double-stranded spirals: (1) orthospirals, which are formed when the two threads being coiled have one end free so that internal twisting does not occur; (2) anorthospirals, which result when two strands with both ends fixed are coiled together and in consequence have a twist compensating for each gyre of the spiral... Orthospirals are interlocked and cannot be separated without untwisting; anorthospirals are independent and can readily be pulled apart or fitted into each other... The term ‘paranemic’ (para = beside) instead of anorthospiral will be used here since it is simpler and its implications are clear.

1950 Biol. Rev. 25 500 Until quite recently almost all observers were agreed that the plectonemic spiral was characteristic of mitosis and the paranemic of meiosis (meaning the first meiotic division).

1953 J. Watson & F. Crick in Cold Spring Harbor Symp. Quant. Biol. 18 129/2 With paranemic coiling, the specific pairing of bases [in DNA] would not allow the successive residues of each helix to be in equivalent orientation with regard to the helical axis.

1983 Proc. National Acad. Sci. U.S.A. 80 1259/1 Previous studies have shown that recA protein can make paranemic joint molecules from circular single strands and homologous superhelical DNA.

1994 Jrnl. Molecular Biol. 243 179/2 The combined results are best explained by the formation of a paranemic foldback structure by each of the individual strands.