AN EXPERIMENTAL INVESTIGATION OF THE BIOPOLYMER ORGANIZATION OF BOTH RECENT AND FOSSIL SPORODERMS

This paper presents, for the first time, new information obtained from a research programme on the biopolymer organization of the sporoderm. The results are as follows: 1. In the TEM photographs of the partiall y degraded exine of Pinus griffithii McClell., 3.0 angstrom diameter m olecular units were observed with fivefold symmetry. Using the modifie d Markham rotation method, secondary points of symmetry were also obse rved indicating that the quasi-crystalloid organization is at the mole cular level. 2. In the partially degraded and fragmented wall of Botry ococcus braunii Kutz., obtained from fossil colonies extracted from th e Hungarian Oil Shale, two kinds of biopolymer structures were observe d in the same fragment. One type was a quasi-equivalent globular unit with a diameter of 50-75 angstrom, whereas the other type consisted of peculiar quasi-crystalloid pentagonal polygons with a diameter of 20- 30 angstrom. Symmetry operations involving the points of the biopolyme r structured wall of the fossil Botryococcus algae were made for the f irst time. A quasi-crystalloid skeleton was also demonstrated as prese nt in this cell wall. 3. A three dimensional model of the sporoderm qu asi-crystalloid skeleton was established. A complete model of the Penr ose-II type biopolymer structure is presented here. This model contain s one central unit, surrounded by two types of Penrose-I units. Eight units can be directly attached to the central unit. An additional six units may be attached to the previous ones by asymmetrical connections . The ''large frustrations'', sensu Nelson 1986, are also asymmetrical with a peculiar asymmetry which can be observed in this large biopoly mer model.