Evidence map›Paper›PMID 18192391›Full record

ArticleJournal of bacteriology2008

Role of periplasmic trehalase in uptake of trehalose by the thermophilic bacterium Rhodothermus marinus.

Carla D Jorge, Luís L Fonseca, Winfried Boos, Helena Santos

Open access · bronzeAbstract read
In one paragraph

Article in Journal of bacteriology, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact, top 81% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed, 1 citations in OpenAlex.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors at 2 institutions in 2 countries.

Carla D JorgeInstituto Tecnologia Química e Biológica/UNL, Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal.
Luís L Fonseca
Winfried Boos
Helena Santos
Universidade Nova de Lisboa · PTUniversity of Konstanz · DE

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Trehalose uptake at 65 degrees C in Rhodothermus marinus was characterized. The profile of trehalose uptake as a function of concentration showed two distinct types of saturation kinetics, and the analysis of the data was complicated by the activity of a periplasmic trehalase. The kinetic parameters of this enzyme determined in whole cells were as follows: Km = 156 +/- 11 microM and Vmax = 21.2 +/- 0.4 nmol/min/mg of total protein. Therefore, trehalose could be acted upon by this periplasmic activity, yielding glucose that subsequently entered the cell via the glucose uptake system, which was also characterized. To distinguish the several contributions in this intricate system, a mathematical model was developed that took into account the experimental kinetic parameters for trehalase, trehalose transport, glucose transport, competition data with trehalose, glucose, and palatinose, and measurements of glucose diffusion out of the periplasm. It was concluded that R. marinus has distinct transport systems for trehalose and glucose; moreover, the experimental data fit perfectly with a model considering a high-affinity, low-capacity transport system for trehalose (Km = 0.11 +/- 0.03 microM and Vmax = 0.39 +/- 0.02 nmol/min/mg of protein) and a glucose transporter with moderate affinity and capacity (Km = 46 +/- 3 microM and Vmax = 48 +/- 1 nmol/min/mg of protein). The contribution of the trehalose transporter is important only in trehalose-poor environments (trehalose concentrations up to 6 microM); at higher concentrations trehalose is assimilated primarily via trehalase and the glucose transport system. Trehalose uptake was constitutive, but the activity decreased 60% in response to osmotic stress. The nature of the trehalose transporter and the physiological relevance of these findings are discussed.

Indexed as

ArsenatesBacterial ProteinsBiological TransportCarbonyl Cyanide m-Chlorophenyl HydrazoneEthanolGlucoseIsomaltoseKineticsModels, TheoreticalPeriplasmRhodothermusSodium FluorideTrehalaseTrehaloseArsenatesBacterial ProteinsCarbonyl Cyanide m-Chlorophenyl HydrazoneEthanolGlucoseIsomaltoseisomaltulosesodium arsenateSodium FluorideTrehalaseTrehalose

Identifiers

PMID18192391
PMCPMC2258883
OpenAlexW2109634785

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.