Bacterial consortium proteomics under 4-chlorosalicylate carbon-limited conditions

Environmental Microbiology Lab, HZI-Helmholtz-Zentrum für Infektionsforschung, Braunschweig, Germany.
Proteomics (Impact Factor: 3.81). 05/2009; 9(8):2273-85. DOI: 10.1002/pmic.200800489
Source: PubMed


In this study, the stable consortium composed by Pseudomonas reinekei strain MT1 and Achromobacter xylosoxidans strain MT3 (cell numbers in proportion 9:1) was under investigation to reveal bacterial interactions that take place under severe nutrient-limiting conditions. The analysis of steady states in continuous cultures was carried out at the proteome, metabolic profile, and population dynamic levels. Carbon-limiting studies showed a higher metabolic versatility in the community through upregulation of parallel catabolic enzymes (salicylate 5-hydroxylase and 17-fold on 2-keto-4-pentenoate hydratase) indicating a possible alternative carbon routing in the upper degradation pathway highlighting the effect of minor proportions of strain MT3 over the major consortia component strain MT1 with a significant change in the expression levels of the enzymes of the mainly induced biodegradation pathway such as salicylate 1-hydroxylase and catechol 1,2-dioxygenase together with important changes in the outer membrane composition of P. reinekei MT1 under different culture conditions. The study has demonstrated the importance of the outer membrane as a sensing/response protective barrier caused by interspecies interactions highlighting the role of the major outer membrane proteins OprF and porin D in P. reinekei sp. MT1 under the culture conditions tested.

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Available from: Roberto Bobadilla-Fazzini, Nov 23, 2015
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    • "Readiness to utilize alternative carbon substrates In contrast to previous studies on microbial physiology under carbon limitation, where chemostats were run at growth rates of 0.01 h −1 and above [2] [3] [16] [36] [39], the current study investigated the physiology of G. metallireducens at growth rates below 0.003 h −1 , which might be more relevant for carbonlimited environments [21]. It was expected that such low growth rates might induce an energy-saving mode in G. metallireducens and prevent expression of many alternative catabolic pathways when their substrates are not readily available. "
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