Membranes recycling

NA Bradbury, T Jilling, G Berta, EJ Sorscher, RJ Bridges, KL Kirk. (1992). Regulation of plasma membrane recycling by CFTR. Science 256 530-532. 

UCH-L3 Ubiquitin fused to small Regulates membrane recycling of epithelial sodium 161... 

Figure 14.8 Simple diagram of release of neurotransmitter and recycling of the vesicles in presynaptic neurone. After exocytosis, the membrane recycles to form a new vesicle which is re-filled with neurotransmitter. The Ca ion binding protein may control packaging, formation of fusion pore and release of neurotransmitter.

Fig. 5.9. Receptor desensitization translocation and arrestin binding. The Py-complex released on activation of the G-protein associates with the P-adrenergic receptor kinase (PARK) and rec-rnits this to the membrane. Consequently, the PARK phosphorylates the activated P-receptor and removes it from the signal chain. Arrestin binds to the phosphorylated receptor. In the arrestin-bound form, the signal can no longer be transmitted to the G-protein and signal conduction is disrupted. The phosphorylated receptor is transported in the form of vesicles into the cell interior (internahzation) and, after dephosphorylation, is returned to the membrane (recycling).

By resorting to the so-called membrane recycle bioreactors (MBR) (Bubbico et al., 1997 Enzminger and Asenjo, 1986), continuous recycling of the culture broth through crossflow MF modules allows removal of the inhibiting metabolites, this helping to maximize cell density in the bioreactor, as well as bioproduct formation rate. Further ED treatment of MF permeates gives rise to two streams, a diluted one to be recycled back into the bioreactor, and a concentrated one to be supplementary refined. 

Bubbico, R., Lo Presti, S., and Moresi, M. 1997. Repeated batch citrate production by Yarrowia lipolytica in a membrane recycle bioreactor. In Engineering Food at ICEF7. Part I (R. Jowitt, ed.), pp. B21-B24. Sheffield Academic Press, Sheffield, UK. 

Raub TJ, Audus KL. Adsorptive endocytosis and membrane recycling by cultured primary bovine brain microvessel endothelial cell monolayers. J Cell Sci 1990 97 (pt 1) 127—138. 

Lapierre LA, Kumar R, Hales CM, Navarre J, Bhartur SG, et al. 2001. Myosin Vb is associated with plasma membrane recycling systems. Mol Biol Cell 12 1843-1857. 

Schmid, S. L. Fuchs, R. Male, R Mellman, I. Two distinct subpopulations of endosomes involved in membrane recycling and transport to lysosomes. CeU 1988, 52, 73-83. 

Siegel JH, Brownell WE (1986) Synaptic and Golgi membrane recycling in cochlear hair cells. J Neurocytol 75 311-328. 

Sudhof, T.C. and Jahn, R. (1991). Proteins of synaptic vesicles involved in exocytosis and membrane recycling. Neuron 6 665-677. 

The endocytotic recycling pathways of polarized epithelial cells (Fig. 8.5), such as en-terocytes, are generally more complex than those in nonpolarized cells. In these entero-cytes there is a common recycling compartment (CRC) that receives molecules from both apical and basolateral membranes and is able to correctly return them to the appropriate membrane or membrane recycling compartment (ARC or BLRC) (25). The signals required for this sorting step have not been defined as of yet, but are presumably similar to... 

Figure 7.44 Fermentation kinetics of a membrane recycle fermentor. Feed concentration = 150 g/C lactose. Cell concentration = 90 g/C.89...

Dijfusion contact reactors Tubular dense membrane/recycle UF HF/single-pass... 

Tubular dense membrane/recycle Whole cell-mediated epoxidation of 1,7-octadiene [148]... 

A process flow diagram for producing ethanol and lactic acid from cheese whey by fermentation with the aid of a membrane recycle bioreactor (MRB) is shown in Figure 3.26 [23]. The UF permeate (WPC in the retentate) contains lactose, nonprotein nitrogen and dissolved salts and is then concentrated by RO to the desired sugar... 

Figure 3.26 Processing of cheese whey using multiple membrane systems and a membrane recycle bioreactor. Source Cheryan, Copyright 1998 from Ultrafiltration and Microfiltration Handbook by M. Cheryan. Reproduced by permission of Routledge/Taylor Francis Group, LLC.

With regard to the fermenters, the most common configurations are membrane recycle fermentor (MRF) and hollow fibre fermentor (HFF). In the MRF the membrane module forms a semi-closed loop with a conventional fermentation vessel the MRF gives much better performance than the HFF, where the microbial cells are loaded onto the shell-side and the feed is pumped through the lumen side. Further advantages of this system are a cell/particulate-free product stream and the reduction of capital costs. Furthermore, in these systems cell growth is a caitical point. 

Escobar et al (2001) did a complete study in which pilot plant trials were conducted in a corn wet mill with a 7000-L membrane recycle bioreactor (MRB) that integrated ceramic microflltration membranes in a semi-closed loop configuration with a stirred-tank reactor. Residence times of 7.5-10 h... 

Mehaia M A, Cheryan M, (1986), Lactic acid from acid whey permeate in a membrane recycle bioreactor . Enzyme and Microbial Technology, 8(5), 289-292. 

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