Lateral heterogeneity

The ability to image lateral heterogeneity in Langmuir monolayers dates back to Zocher and Stiebel s 1930 study with divergent light illumination [166]. More recently the focus shifted toward the use of fluorescence microscopy of mono-layers containing a small amount of fluorescent dye [167]. Even in single-corn-... 

As w ell as lateral heterogeneity in mixed protein layers, there is also the possibility of segregation of biopolymer components perpendicular to the interface, z.e., bilayer formation (Dickinson, 1995, 2009). Let us consider the case of an interface containing casein and whey protein in an emulsion system. The images in Figure 8.4 are confocal micrographs... 

Andersson, B. and Anderson J.M. 1980. Lateral heterogeneity in the distribution of chlorophyll-protein complexes of the thylakoid membranes of spinach chloroplasts. Biochim. Biophys. Acta 593.427-440. 

This review focusses on certain aspects of the transverse arrangement of the proteins and lipids of thylakoid membranes, and the lateral heterogeneity of these complexes between the appressed and non-appressed regions of Chi b-containing plants. The consequences of lateral heterogeneity will also be examined with the emphasis on areas under debate. 

Lateral heterogeneity in the location of thylakoid intrinsic complexes... 

Early fractionation studies with thylakoids that had been fragmented by detergents [54] or mechanical means [55] followed by collection of the thylakoid submembrane fractions by centrifugation provided the first evidence for lateral heterogeneity. Submembrane fractions derived from granal stacks were enriched in PS II but they also contained PS 1, whereas the stroma thylakoids had mainly PS I. Sane et al. [55] proposed that appressed membranes were the site of non-cyclic electron transport, while the non-appressed membranes carried out cyclic photo-... 

Fig. 5. Possible static representation of the lateral heterogeneity in the distribution of the supramole-cular thylakoid complexes between appressed and non-appressed thylakoids [62,63].

Lateral heterogeneity has profound consequences for thylakoid function and structure [4,6,63] despite some uncertainty prevailing as to the absolute extent of lateral heterogeneity of the PS I complex, and the location of the Cyt 6//complex in both appressed and non-appressed membrane regions. 

To resolve this issue, it is crucial to establish whether there are some PS I complexes in the appressed grana partitions or none at all. The suggestion of extreme lateral heterogeneity with exclusion of all PS I complexes from appressed mem-... 

Dziewonski A. M. (1984) Mapping the lower mantle determination of lateral heterogeneity in P velocity up to degree and order 6. J. Geophys. Res. 89, 5929-5952. 

Many Archaean cratons show marked lateral heterogeneity. This heterogeneity can be expressed by many different attributes ages and distribution of greenstone belts, plutonic and (or) metamorphic age domains, contrasting struc-... 

The lateral heterogeneity of Archaean cratons, together with their structural and stratigraphic complexity, favours a mobile tectonic regime (e.g. Burke et al. 1976) that, at least in some... 

The top panel of Fig. 3.2 presents a selection of results for the lateral organization of some simple one- and two-component lipid bilayers that have been investigated by computer-simulation calculations and atomic force microscopy. A pronounced degree of lateral heterogeneity in terms of lipid domains is found. The lipid domains are either solid hpid patches in fluid bilayers or fluid lipid patches in solid bilayers. In lipid mixtures, the domains may reflect incomplete phase separation. The sizes, the morphology, and the topology of the lipid domain patterns depend on the lipid composition and the thermodynamic conditions. The domains can be enhanced or suppressed by adding further lipid components or solutes [36]. 

B Andersson and JM Anderson (1980) Lateral heterogeneity in the distribution of chlorophyll-protein complexes of the thylakoid membranes of spinach chloroplasts. Biochim Biophys Acta 593 427-440 P-" Albertsson (1985) Partition of Cell Particles and Macromolecules (3rd edition) John Wiley H-E "kerlund, B Andersson and P-" Albertsson (1976) Isolation of photosystem II enriched membrane vesicles from spinach chloroplasts by phase partition. Biochim Biophys Acta 449 525-535 P Grber, A Zickler and H-E "kerlund (1978) Electric evidence for the isolation of inside-out vesicles from spinach chloroplasts. FEES Lett 96 233-237... 

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