Maltose transport in Escherichia coli K-12: involvement of the bacteriophage lambda receptor

Szmelcman, Sevec; Hofnung, Maurice

doi:10.1128/jb.124.1.112-118.1975

Cited by 302 publications

(160 citation statements)

References 17 publications

Supporting

Mentioning

157

Contrasting

Unclassified

Order By: Relevance

“…The following hypothesis might explain why the combined cost of resistance in E. coli to viruses T4 and A is less than expected from the separate costs for each virus alone, especially in trehalose. Mutations that confer resistance to A usually cause loss or structural modification of the LamB protein, the outer membrane receptor to which A initially binds to the bacterial cell (Szmelcman and Hofnung 1975;Arber 1983). LamB is involved in the uptake of maltose and trehalose, but not glucose (Klein and Boos 1993;Travisano and Lenski 1996).…”

Section: Discussionmentioning

confidence: 99%

Epistatic Interactions Can Lower the Cost of Resistance to Multiple Consumers

Bohannan¹,

Travisano²,

Lenski³

1999

Evolution

View full text Add to dashboard Cite

It is widely assumed that resistance to consumers (e.g., predators or pathogens) comes at a "cost," that is, when the consumer is absent the resistant organisms are less fit than their susceptible counterparts. It is unclear what factors determine this cost. We demonstrate that epistasis between genes that confer resistance to two different consumers can alter the cost of resistance. We used as a model system the bacterium Escherichia coli and two different viruses (bacteriophages), T4 and Λ, that prey upon E. coli. Epistasis tended to reduce the costs of multiple resistance in this system. However, the extent of cost savings and its statistical significance depended on the environment in which fitness was measured, whether the null hypothesis for gene interaction was additive or multiplicative, and subtle differences among mutations that conferred the same resistance phenotype.

show abstract

Section: Discussionmentioning

confidence: 99%

Epistatic Interactions Can Lower the Cost of Resistance to Multiple Consumers

Bohannan¹,

Travisano²,

Lenski³

1999

Evolution

View full text Add to dashboard Cite

show abstract

“…Among them, a small number convey selective permeability to compounds larger than the exclusion size. One of them is induced by growth on maltose (Szmelcman and Hofnung, 1975), and allows growth at low concentrations of maltose or in the presence of maltose oligomers. Thus, maltodextrins up to the size of maltoheptaose, a compound well above the apparent pore size, are transported into cells Nakae and Ishii, 1980).…”

Section: Introductionmentioning

confidence: 99%

“…In vivo, Escherichia coli takes up maltose by the sequential action of several proteins encoded in the maltose B operon (Hofnung, 1974). Transport substrates diffuse into the peripplasmic space through the channels formed by maltoporin (Szmelcman and Hofnung, 1975). They are then bound to the soluble maltose-binding protein (Kellermann and Szmelcman, 1974) which delivers the sugar to the system which actively transports it across the cytoplasmic membrane (Shuman et al, 1980).…”

mentioning

confidence: 99%

The periplasmic maltose-binding protein modifies the channel-forming characteristics of maltoporin.

Neuhaus¹,

Schindler²,

Rosenbusch³

1983

The EMBO Journal

View full text Add to dashboard Cite

Maltoporin, a protein spanning Escherichia coli outer membranes, modifies electrical conductance of membranes due to its channel‐forming properties. This observation was made by conductance measurements across planar bilayers which were derived from unextracted, isolated outer membrane vesicles using a porin‐deficient E. coli strain. Alternatively, proteoliposomes reconstituted with detergent‐solubilized homogeneous maltoporin and phospholipids were used. With either membrane preparation, channel conductance was observed, although no discrete conductance levels were detected. The presence of lipopolysaccharide, a bacterial glycolipid, was not required, nor did it affect channel activity. In the presence of the water‐soluble periplasmic maltose‐binding protein, conductance fluctuations occurred in discrete steps, demonstrating opening and closing events of channels. Multiple step sizes (1/3, 2/3 and 1 ns in 1 M KCl) in single channel traces suggest cooperative opening and closing of up to three channels. The action of maltose‐binding protein is highly asymmetrical, and its affinity to maltoporin is very high (KD = 1.5 X 10(‐7) M). Association of maltose‐binding protein to maltoporin shifts, for a given polarity, the equilibrium between open and closed states in favour of closed states. This result matches earlier in vivo studies, and supports the physiological significance of the observations made.

show abstract

“…Their relative amounts are determined by the osmotic pressure of the growth medium (van Alphen and Lugtenberg, 1977). The synthesis of PhoE protein is induced when cells are growing under (c)IRL Press Limited, Oxford, England phosphate limitation (Overbeeke and Lugtenberg, 1980) while LamB protein is induced by the presence of maltose (Szmelcman and Hofnung, 1975). Nucleotide sequence analysis of the ompF, ompC, phoE genes (Inokuchi et al, 1982;Mizuno et al, 1983) has revealed an extensive homology of -60% in the primary structures of these three proteins while LamB protein is apparently unrelated to the other porins (Clement and Hofnung, 1981).…”

mentioning

confidence: 99%

Three-dimensional reconstruction of maltoporin from electron microscopy and image processing.

Lepault¹,

Tichelaar²,

Rosenbusch³

et al. 1988

The EMBO Journal

View full text Add to dashboard Cite

Two dimensional crystals of maltoporin (or phage lambda receptor) were obtained by reconstitution of purified maltoporin trimers and Escherichia coli phospholipids by detergent dialysis. Two different trimer packing forms were observed. One was hexagonal (a = 7.8 nm) and one rectangular (a = 7.8 nm, b = 13.6 nm). In this paper we describe the three‐dimensional structure of maltoporin, deduced from the study of the rectangular form by electron microscopy and image processing. At a resolution of approximately 2.5 nm, maltoporin trimers form aqueous channel triplets which appear to merge into a single outlet at the periplasmic surface of the outer membrane. The pore defined by maltoporin has a similar structure to that outlined by the matrix protein. From the results of functional studies by conductance measurement, it is concluded that the three channels defined by maltoporin act, contrary to those formed by the porin (OmpF protein), as a single conducting unit. A tentative outline of the maltoporin promoter is given. Maltoporin appears to be constituted by three different domains: a major rod‐like domain spanning the membrane, a minor domain located near the periplasmic surface of the membrane and finally a central domain responsible for the splitting of the channel.

show abstract

Maltose transport in Escherichia coli K-12: involvement of the bacteriophage lambda receptor

Cited by 302 publications

References 17 publications

Epistatic Interactions Can Lower the Cost of Resistance to Multiple Consumers

Epistatic Interactions Can Lower the Cost of Resistance to Multiple Consumers

The periplasmic maltose-binding protein modifies the channel-forming characteristics of maltoporin.

Three-dimensional reconstruction of maltoporin from electron microscopy and image processing.

Contact Info

Product

Resources

About