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The peptide fragment of the light harvesting complex II comprising the trimerisation site binds strongly and selectively to phosphatidylglycerol while the affinity to the other LHCII-bound lipid digalactosyldiacylglycerol is negligible. Upon its binding, large aggregates of the lipid are formed which do not occur in the presence of other peptides, in particular the peptide comprising the phosphorylation site. Our observation supports a hypothesis that the trimerisation site of LHCII is also the specific binding site for phosphatidylglycerol and favors another hypothesis that the phosphorylation site is directly involved in the control of trimerisation.

The validity of relations established for the calculation of the interfacial area of a liquid flowing along an inclined partially-wetted tube (Part I) was verified experimentally. The measurement of the interfacial area was carried out by means of a chemical method. The variables were: volumetric liquid flow rate, slope angle of the tube, its diameter, and the contact angle, whose value was influenced by the material of the tube. The experimental data were compared with the results calculated according to the method suggested in the Part I of the present study. The results were in a good agreement with the theory in the case of higher contact angles (i.e., for tubes made of steel or PVC), while in the cases where small contact angle values were expected on the basis of theory (glass), the results differed significantly. This discrepancy was attributed to the effect of traces of impurities present in the solution, which accumulated on the surface of tube, bringing about a gradual increase in the contact angle value in the course of experiments. The effect on the lower surface energy materials such as PVC or steel are less marked than on the glass. There is, therefore, the limitation of the theory given in Part I because of the uncertainty of the contact angle to be used for a given situation.

The calculation of the profile of a liquid film flowing along an inclined cylindrical surface, that is not completely wetted, is presented. Surface tension and contact angle are taken into consideration, and wave motion is neglected. The situation is described by a second order non-linear differential equation. A general solution, represented by a set of elliptical integrals, is given in dimensionless formThe case of liquid film hanging from and flowing along a wire of circular cross-section is discussed in detail. For selected values of wire diameter and contact angle a set of profiles was obtained numerically. The liquid hold-up as well as the corresponding interfacial area of gas-liquid contact were obtained. Further, the method enables us to calculate the gas-liquid interfacial area from the liquid hold-up. In the case of a laminar flow, it is possible to carry out a complete analysis of the problem, including no empirical parameter, on solving the Navier-Stokes equation.

A novel homolog of insect defensin, designated lucifensin II (Lucilia cuprina Wiedemann [Diptera: Calliphoridae] defensin), was purified from hemolymph extract from larvae of the blowfly L. cuprina. The full-length primary sequence of this peptide of 40 amino acid residues and three intramolecular disulfide bridges was determined by electrospray ionization-orbitrap mass spectrometry and Edman degradation and is almost identical to the previously identified sequence of lucifensin (Lucilia sericata Meigen defensin). Lucifensin II sequence differs from that of lucifensin by only one amino acid residue, that is, by isoleucine instead of valine at position 11. The presence of lucifensin II also was detected in the extracts of other larval tissues, such as gut, salivary glands, fat body, and whole body extract.