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Proteomic analysis of Chromobacterium violaceum and its adaptability to stress.

Castro D, Cordeiro IB, Taquita P, Eberlin MN, Garcia JS, Souza GH, Arruda MA, Andrade EV, Filho SA, Crainey JL, Lozano LL, Nogueira PA, Orlandi PP - BMC Microbiol. (2015)

Bottom Line: With the exception of the ribosomal subunit L3, which plays a role in protein folding and maybe therefore be more useful in stressful conditions, all the other ribosomal subunit proteins were seen to have reduced expression in stressed cultures.Analysis of the proteomic signatures of stressed C. violaceum indicates that nutrient-starvation and pH stress can cause changes in the expression of the C. violaceum receptors, transporters, and proteins involved with biosynthetic pathways, molecule recycling, energy production.Our findings complement the recent publication of the C. violeaceum genome sequence and could help with the future commercial exploitation of C. violeaceum.

View Article: PubMed Central - PubMed

Affiliation: Instituto Leônidas e Maria Deane - ILMD- Fiocruz, 476 Teresina St., 69057-070, Manaus, AM, Brazil. diogocastrop@gmail.com.

ABSTRACT

Background: Chromobacterium violaceum (C. violaceum) occurs abundantly in a variety of ecosystems, including ecosystems that place the bacterium under stress. This study assessed the adaptability of C. violaceum by submitting it to nutritional and pH stresses and then analyzing protein expression using bi-dimensional electrophoresis (2-DE) and Maldi mass spectrometry.

Results: Chromobacterium violaceum grew best in pH neutral, nutrient-rich medium (reference conditions); however, the total protein mass recovered from stressed bacteria cultures was always higher than the total protein mass recovered from our reference culture. The diversity of proteins expressed (repressed by the number of identifiable 2-DE spots) was seen to be highest in the reference cultures, suggesting that stress reduces the overall range of proteins expressed by C. violaceum. Database comparisons allowed 43 of the 55 spots subjected to Maldi mass spectrometry to be characterized as containing a single identifiable protein. Stress-related expression changes were noted for C. violaceum proteins related to the previously characterized bacterial proteins: DnaK, GroEL-2, Rhs, EF-Tu, EF-P; MCP, homogentisate 1,2-dioxygenase, Arginine deiminase and the ATP synthase β-subunit protein as well as for the ribosomal protein subunits L1, L3, L5 and L6. The ability of C. violaceum to adapt its cellular mechanics to sub-optimal growth and protein production conditions was well illustrated by its regulation of ribosomal protein subunits. With the exception of the ribosomal subunit L3, which plays a role in protein folding and maybe therefore be more useful in stressful conditions, all the other ribosomal subunit proteins were seen to have reduced expression in stressed cultures. Curiously, C. violeaceum cultures were also observed to lose their violet color under stress, which suggests that the violacein pigment biosynthetic pathway is affected by stress.

Conclusions: Analysis of the proteomic signatures of stressed C. violaceum indicates that nutrient-starvation and pH stress can cause changes in the expression of the C. violaceum receptors, transporters, and proteins involved with biosynthetic pathways, molecule recycling, energy production. Our findings complement the recent publication of the C. violeaceum genome sequence and could help with the future commercial exploitation of C. violeaceum.

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Related in: MedlinePlus

Identification of expressed proteins by MALDI/MS. C. violaceum proteins under pH stress: a Proteins associated with bacterial responses; b Biosynthesis related proteins; c Energy and metabolism related proteins
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Fig3: Identification of expressed proteins by MALDI/MS. C. violaceum proteins under pH stress: a Proteins associated with bacterial responses; b Biosynthesis related proteins; c Energy and metabolism related proteins

Mentions: Some of the identifiable proteins seem to be correlated with nutrient-starvation survival strategies including biosynthesis, molecules recycling and energy production [22]. The identified spots included proteins belonging to energetic metabolism, elements of biosynthetic pathways like chaperones, ribosomal proteins, transporters, and receptors (see Table 2). Fifteen spots corresponding to 15 characterized proteins were classified into three major functional groups that were analyzed quantitatively (See Fig. 3a–c). The first functional group, referred to here as the “molecule recycling group”, was represented with just one protein: the polyhydroxy butyrate protein (PhbF) (Fig. 3a). The second group, referred to here as the “biosynthesis protein group” was comprised of proteins, such as elongation factors and ribosomal subunits (Fig. 3b). The third group protein group was comprised of proteins related to energy production and metabolism and is referred to here as the “energy related” protein group (Fig. 3c).Fig. 3


Proteomic analysis of Chromobacterium violaceum and its adaptability to stress.

Castro D, Cordeiro IB, Taquita P, Eberlin MN, Garcia JS, Souza GH, Arruda MA, Andrade EV, Filho SA, Crainey JL, Lozano LL, Nogueira PA, Orlandi PP - BMC Microbiol. (2015)

Identification of expressed proteins by MALDI/MS. C. violaceum proteins under pH stress: a Proteins associated with bacterial responses; b Biosynthesis related proteins; c Energy and metabolism related proteins
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4666173&req=5

Fig3: Identification of expressed proteins by MALDI/MS. C. violaceum proteins under pH stress: a Proteins associated with bacterial responses; b Biosynthesis related proteins; c Energy and metabolism related proteins
Mentions: Some of the identifiable proteins seem to be correlated with nutrient-starvation survival strategies including biosynthesis, molecules recycling and energy production [22]. The identified spots included proteins belonging to energetic metabolism, elements of biosynthetic pathways like chaperones, ribosomal proteins, transporters, and receptors (see Table 2). Fifteen spots corresponding to 15 characterized proteins were classified into three major functional groups that were analyzed quantitatively (See Fig. 3a–c). The first functional group, referred to here as the “molecule recycling group”, was represented with just one protein: the polyhydroxy butyrate protein (PhbF) (Fig. 3a). The second group, referred to here as the “biosynthesis protein group” was comprised of proteins, such as elongation factors and ribosomal subunits (Fig. 3b). The third group protein group was comprised of proteins related to energy production and metabolism and is referred to here as the “energy related” protein group (Fig. 3c).Fig. 3

Bottom Line: With the exception of the ribosomal subunit L3, which plays a role in protein folding and maybe therefore be more useful in stressful conditions, all the other ribosomal subunit proteins were seen to have reduced expression in stressed cultures.Analysis of the proteomic signatures of stressed C. violaceum indicates that nutrient-starvation and pH stress can cause changes in the expression of the C. violaceum receptors, transporters, and proteins involved with biosynthetic pathways, molecule recycling, energy production.Our findings complement the recent publication of the C. violeaceum genome sequence and could help with the future commercial exploitation of C. violeaceum.

View Article: PubMed Central - PubMed

Affiliation: Instituto Leônidas e Maria Deane - ILMD- Fiocruz, 476 Teresina St., 69057-070, Manaus, AM, Brazil. diogocastrop@gmail.com.

ABSTRACT

Background: Chromobacterium violaceum (C. violaceum) occurs abundantly in a variety of ecosystems, including ecosystems that place the bacterium under stress. This study assessed the adaptability of C. violaceum by submitting it to nutritional and pH stresses and then analyzing protein expression using bi-dimensional electrophoresis (2-DE) and Maldi mass spectrometry.

Results: Chromobacterium violaceum grew best in pH neutral, nutrient-rich medium (reference conditions); however, the total protein mass recovered from stressed bacteria cultures was always higher than the total protein mass recovered from our reference culture. The diversity of proteins expressed (repressed by the number of identifiable 2-DE spots) was seen to be highest in the reference cultures, suggesting that stress reduces the overall range of proteins expressed by C. violaceum. Database comparisons allowed 43 of the 55 spots subjected to Maldi mass spectrometry to be characterized as containing a single identifiable protein. Stress-related expression changes were noted for C. violaceum proteins related to the previously characterized bacterial proteins: DnaK, GroEL-2, Rhs, EF-Tu, EF-P; MCP, homogentisate 1,2-dioxygenase, Arginine deiminase and the ATP synthase β-subunit protein as well as for the ribosomal protein subunits L1, L3, L5 and L6. The ability of C. violaceum to adapt its cellular mechanics to sub-optimal growth and protein production conditions was well illustrated by its regulation of ribosomal protein subunits. With the exception of the ribosomal subunit L3, which plays a role in protein folding and maybe therefore be more useful in stressful conditions, all the other ribosomal subunit proteins were seen to have reduced expression in stressed cultures. Curiously, C. violeaceum cultures were also observed to lose their violet color under stress, which suggests that the violacein pigment biosynthetic pathway is affected by stress.

Conclusions: Analysis of the proteomic signatures of stressed C. violaceum indicates that nutrient-starvation and pH stress can cause changes in the expression of the C. violaceum receptors, transporters, and proteins involved with biosynthetic pathways, molecule recycling, energy production. Our findings complement the recent publication of the C. violeaceum genome sequence and could help with the future commercial exploitation of C. violeaceum.

Show MeSH
Related in: MedlinePlus