Limits...
The Anabaena sp. PCC 7120 Exoproteome: Taking a Peek outside the Box.

Oliveira P, Martins NM, Santos M, Couto NA, Wright PC, Tamagnini P - Life (Basel) (2015)

Bottom Line: The evidence presented here shows that Anabaena sp.Furthermore, the activity of selected exoproteins associated with oxidative stress has been assessed, suggesting their involvement in redox homeostasis mechanisms in the extracellular space.Finally, we discuss our results in light of other cyanobacterial exoproteome studies and focus on the potential of exploring cyanobacteria as cell factories to produce and secrete selected proteins.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto 4150-180, Portugal. paulo.oliveira@ibmc.up.pt.

ABSTRACT
The interest in examining the subset of proteins present in the extracellular milieu, the exoproteome, has been growing due to novel insights highlighting their role on extracellular matrix organization and biofilm formation, but also on homeostasis and development. The cyanobacterial exoproteome is poorly studied, and the role of cyanobacterial exoproteins on cell wall biogenesis, morphology and even physiology is largely unknown. Here, we present a comprehensive examination of the Anabaena sp. PCC 7120 exoproteome under various growth conditions. Altogether, 139 proteins belonging to 16 different functional categories have been identified. A large fraction (48%) of the identified proteins is classified as "hypothetical", falls into the "other categories" set or presents no similarity to other proteins. The evidence presented here shows that Anabaena sp. PCC 7120 is capable of outer membrane vesicle formation and that these vesicles are likely to contribute to the exoproteome profile. Furthermore, the activity of selected exoproteins associated with oxidative stress has been assessed, suggesting their involvement in redox homeostasis mechanisms in the extracellular space. Finally, we discuss our results in light of other cyanobacterial exoproteome studies and focus on the potential of exploring cyanobacteria as cell factories to produce and secrete selected proteins.

No MeSH data available.


Related in: MedlinePlus

Exoproteome profiles of Anabaena sp. PCC 7120 wild-type (WT) and BSMPo1 [34] cultivated in BG11. The Coomassie-stained SDS-polyacrylamide gel shows the exoproteome of both strains grown for three days in a medium containing nitrate. The protein content present in approximately 3 mL of the growth medium was loaded on each lane. The molecular masses of the Precision Plus Protein All Blue standard (Bio-Rad), Lane M, are indicated on the left, while the arrowhead points to the overexpressed and secreted protein HesF.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4390845&req=5

life-05-00130-f007: Exoproteome profiles of Anabaena sp. PCC 7120 wild-type (WT) and BSMPo1 [34] cultivated in BG11. The Coomassie-stained SDS-polyacrylamide gel shows the exoproteome of both strains grown for three days in a medium containing nitrate. The protein content present in approximately 3 mL of the growth medium was loaded on each lane. The molecular masses of the Precision Plus Protein All Blue standard (Bio-Rad), Lane M, are indicated on the left, while the arrowhead points to the overexpressed and secreted protein HesF.

Mentions: Investigations recently carried out in our laboratory strongly indicate that there is room for engineering and modulating cyanobacterial protein secretion. As presented in Figure 7, the simple fusion of a nitrate inducible promoter with the exoprotein encoding gene, hesF, resulted in the overexpression of the protein, leading to an over-accumulation of HesF in the extracellular milieu. Furthermore, this result also highlights that even though a signal peptide could not be identified in the sequence of HesF, whatever addresses the protein for secretion seems to be highly efficient [34].


The Anabaena sp. PCC 7120 Exoproteome: Taking a Peek outside the Box.

Oliveira P, Martins NM, Santos M, Couto NA, Wright PC, Tamagnini P - Life (Basel) (2015)

Exoproteome profiles of Anabaena sp. PCC 7120 wild-type (WT) and BSMPo1 [34] cultivated in BG11. The Coomassie-stained SDS-polyacrylamide gel shows the exoproteome of both strains grown for three days in a medium containing nitrate. The protein content present in approximately 3 mL of the growth medium was loaded on each lane. The molecular masses of the Precision Plus Protein All Blue standard (Bio-Rad), Lane M, are indicated on the left, while the arrowhead points to the overexpressed and secreted protein HesF.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4390845&req=5

life-05-00130-f007: Exoproteome profiles of Anabaena sp. PCC 7120 wild-type (WT) and BSMPo1 [34] cultivated in BG11. The Coomassie-stained SDS-polyacrylamide gel shows the exoproteome of both strains grown for three days in a medium containing nitrate. The protein content present in approximately 3 mL of the growth medium was loaded on each lane. The molecular masses of the Precision Plus Protein All Blue standard (Bio-Rad), Lane M, are indicated on the left, while the arrowhead points to the overexpressed and secreted protein HesF.
Mentions: Investigations recently carried out in our laboratory strongly indicate that there is room for engineering and modulating cyanobacterial protein secretion. As presented in Figure 7, the simple fusion of a nitrate inducible promoter with the exoprotein encoding gene, hesF, resulted in the overexpression of the protein, leading to an over-accumulation of HesF in the extracellular milieu. Furthermore, this result also highlights that even though a signal peptide could not be identified in the sequence of HesF, whatever addresses the protein for secretion seems to be highly efficient [34].

Bottom Line: The evidence presented here shows that Anabaena sp.Furthermore, the activity of selected exoproteins associated with oxidative stress has been assessed, suggesting their involvement in redox homeostasis mechanisms in the extracellular space.Finally, we discuss our results in light of other cyanobacterial exoproteome studies and focus on the potential of exploring cyanobacteria as cell factories to produce and secrete selected proteins.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto 4150-180, Portugal. paulo.oliveira@ibmc.up.pt.

ABSTRACT
The interest in examining the subset of proteins present in the extracellular milieu, the exoproteome, has been growing due to novel insights highlighting their role on extracellular matrix organization and biofilm formation, but also on homeostasis and development. The cyanobacterial exoproteome is poorly studied, and the role of cyanobacterial exoproteins on cell wall biogenesis, morphology and even physiology is largely unknown. Here, we present a comprehensive examination of the Anabaena sp. PCC 7120 exoproteome under various growth conditions. Altogether, 139 proteins belonging to 16 different functional categories have been identified. A large fraction (48%) of the identified proteins is classified as "hypothetical", falls into the "other categories" set or presents no similarity to other proteins. The evidence presented here shows that Anabaena sp. PCC 7120 is capable of outer membrane vesicle formation and that these vesicles are likely to contribute to the exoproteome profile. Furthermore, the activity of selected exoproteins associated with oxidative stress has been assessed, suggesting their involvement in redox homeostasis mechanisms in the extracellular space. Finally, we discuss our results in light of other cyanobacterial exoproteome studies and focus on the potential of exploring cyanobacteria as cell factories to produce and secrete selected proteins.

No MeSH data available.


Related in: MedlinePlus