Isolation and characterization of plasma membranes from cyanobacteria

Abstract

S. 1997. Isolation and characterization of plasma membranes from cyanobacteria. -Pliysiol. Plant. 99: 495-504.The two-phase partition system in comparison to the traditional methods used thus far (density gradients) for the isolation of tlie plasma membrane from cyanobacteria is described. The advantages of the two-phase system are: A short-time preparation of 3-4 h compared to 16-48 h required for the density gradient method; a purer fraction, resulting from separation according to membrane surface charge and hydrophobicity, not specific density; and, ease of scaling-up for obtaining large quantities. Also, the different biological activities attributed to this membrane to date are summarized. Findings on the typical plasma membrane ATPase (P-type ATPase) as well as the nutrient transporters and the corresponding proteins are included. As for the electron transport chain, one may conclude that this membrace contains a complete system (similar to that of the mitochondrion), portraying apparently F-type (F9F1) ATPase activity.

The Plasma Membrane of the Cyanobacterium Gloeobacter violaceus Contains Segregated Bioenergetic Domains

“…The centrifugation resulted in the separation of an orange and a green membrane fraction with densities of 1.07 and 1.16 g/mL, respectively (Figure 1). The properties of these membrane fractions in terms of protein composition, pigment content, and buoyant density are consistent with the characteristics published for cyanobacterial plasma or thylakoid membranes (Omata and Murata, 1983;Molitor and Peschek, 1986;Norling et al, 1997;Zak et al, 2001;Huang et al, 2002). They clearly differ from the properties of the outer membrane, which can be isolated at a density of 1.19 g/mL when the interface between 48 and 50% layer of the first gradient is applied to a second sucrose gradient ( Figure 1D).…”

“…The distribution of proteins between the two membrane domains of G. violaceus resembles the distribution of membrane proteins between plasma and thylakoid membrane in other cyanobacteria (Norling et al, 1997;Zak et al, 2001;Huang et al, 2002). In particular, the exclusive localization of NADH dehydrogenase (Ohkawa et al, 2001;Zhang et al, 2004) and cytochrome b 6 f complexes (Aldridge et al, 2008;Schultze et al, 2009) in the thylakoid membrane (and their absence from the plasma membrane) has been shown for the cyanobacterium Synechocystis PCC 6803.…”

2D‐isolation of pure plasma and thylakoid membranes from the cyanobacterium Synechocystis sp. PCC 6803

“…Plasma membranes from the cyanobacterium Phormidium laminosum have been isolated using aqueous two-phase partitioning [15,16], a procedure that separates according to the surface properties of the membrane vesicles, such as charge and hydrophobicity rather than their size and densities [5]. The plasma membranes were virtually free of chlorophyll, demonstrating no cross-contamination by thylakoid membranes.…”

Functional Characterization of the Small Regulatory Subunit PetP from the Cytochrome b6f Complex in Thermosynechococcus elongatus

“…However, for both thylakoid membrane systems of plants and cyanobacteria, the distribution of b 6 f is still unclear with most authors believing in an even distribution of this complex over the whole membrane (Hinshaw and Miller, 1993;Kirchhoff et al, 2000;Allen and Forsberg, 2001) or a state dependent distribution of b 6 f (Vallon et al, 1991). In cyanobacterial thylakoids, b 6 f is central to both photosynthetic and respiratory electron transport chain (Norling et al, 1997;Zak et al, 2001;Huang et al, 2002;Schultze et al, 2009), which are separated into chloroplasts and mitochondria in plants. Also, mitochondria contain a bc 1 complex instead of b 6 f (Widger et al, 1984).…”