Influence of rehydration on transcriptome during resuscitation of desiccated Pseudomonas putida KT2440

Purpose Pseudomonas putida KT2440 is a desiccation-sensitive bacterium that loses culturability after 15 days of air desiccation. We have previously shown that P. putida KT2440 can develop a viable but nonculturable (VBNC) state after being exposed to desiccation stress and eventually recover when desiccated cells are rehydrated for at least 24 h. Methods To determine which genes of transport, oxidation-reduction, and transcription processes could be involved in the return of P. putida KT2440 to the culturable state, a transcriptome analysis was carried out comparing the gene expression of non-desiccated samples with samples subjected to desiccation followed by 20 min of rehydration or desiccation followed by 24 h of rehydration. Results Desiccation stress triggered a VBNC state of P. putida. The major response was detected after 24 h of rehydration with 148 upregulated and 42 downregulated genes. During the VBNC state, P. putida activated transmembrane transport processes like that of siderophores through a TonB-dependent transporter and putative polyhydric alcohol transport systems. Prolonged rehydration with distilled water resuscitated P. putida KT2440 cells activating the catabolism of phenylalanine/tyrosine to provide energy and carbon for ubiquinone biosynthesis while maintaining a reduced protein synthesis. On the other hand, the interruption of the TonB-dependent receptor gene (PP_1446) increased desiccation survival of the mutant strain. Conclusion The activation of the iron transport system (TonB-dependent siderophore receptor) and alcohol transport can be helping the VBNC state of P. putida. Activation of catabolism of phenylalanine/tyrosine and reduced protein synthesis was needed for resuscitation from the VBNC state.

EMOTIONAL ATTITUDES LINKED TO COMMON OBJECTS: PRACTICAL AND CLINICAL IMPLICATIONS

Studies concerning emotional changes following brain damage neglect the emotional responses that might arise in reaction to the stimuli used in their examination of such patients. Yet those reactions may be quite forceful often provoking feeling of anxiety or panic and dismay. A questionnaire designed to reveal associations and emotional attitudes was presented to 96 extramural students. Four categories of products and the products within those categories were selected. The categories included: sweets; alcohol; transport, and consumer electronics. In addition, 174 participants of various ages and professions produced associations linked to emotionally loaded words. A list of associations and their dominance scores were created. It revealed that transport (4.9) and consumer electronics (5) were given the highest mean scores. Also, the terms car (5.3) and mobile phone (5) aroused the highest levels of emotion. The significance of the emotional attitudes of the participants to objects were determined within particular dimensions that measured likableness, interest, goodness, and attractiveness. The terms beer, chocolate, car and mobile phone were reported to be most acceptable in all four dimensions. The above data suggests that the emotional attitude awakened by a particular object finds its expression in all of the dimensions examined. The studies revealed the significance of primary subconscious affects for creating positive or negative attitudes. This should be taken into account by therapists since objects which evoke a negative affect may trigger a patient’s reluctance to take part in the rehabilitation procedure.