In:
Lipids, Wiley, Vol. 33, No. 6 ( 1998-06), p. 617-625
Abstract:
The major alkenes of the haptophytes Isochrysis galbana (strain CCAP 927/14) and Emiliania huxleyi (strains CCAP 920/2 and VAN 556) have been identified by nuclear magnetic resonance spectroscopy and by mass spectrometric analysis of their dimethyl disulfide adducts. The dominant alkene in I. galbana is (22 Z )‐1,22‐hentriacontadiene, with 1,24‐hentriacontadiene and 1,24‐tritriacontadiene present in much lower abundance; (22 Z )‐1,22‐hentriacontadiene also occurs in E. huxleyi (strain CCAP 920/2), together with (2 Z ,22 Z )‐2,22‐hentriacontadiene (the major hydrocarbon) and (3 Z ,22 Z )‐3,22‐hentriacontadiene. Minor abundances of 2,24‐hentriacontadiene and 2,24‐tritriacontadiene are also present in this strain. In contrast, the dominant alkene in E. huxleyi (strain VAN 556) is (15 E ,22 E )‐1,16,23‐heptatriacontatriene with the related alkatriene 1,15,22‐octatriacontatriene also present and (22 Z )‐1,22‐hentriacontadiene occurring as a minor component. From structural relationships (15 E ,22 E )‐1,15,22‐heptatriacontatriene is proposed to derive from the same biosynthetic pathway as that of the characteristic C 37 alkenones which occur in both E. huxleyi and I. galbana . The C 31 and C 33 dienes likely derive from chain extension and decarboxylation of ( Z )‐9‐octadecenoic acid or ( Z )‐7‐hexadecenoic acid, using a pathway analogous to that elucidated previously in the chlorophyte Botryococcus braunii . Therefore, long‐chain dienes and trienes, which can co‐occur in haptophytes, may have distinct biosynthetic pathways.
Type of Medium:
Online Resource
ISSN:
0024-4201
,
1558-9307
DOI:
10.1007/s11745-998-0248-0
Language:
English
Publisher:
Wiley
Publication Date:
1998
detail.hit.zdb_id:
2030265-4
SSG:
12
Permalink