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Pilin Processing Follows a Different Temporal Route than That of Archaellins in Methanococcus maripaludis.

Nair DB, Jarrell KF - Life (Basel) (2015)

Bottom Line: In contrast, pilins are not glycosylated unless they have been acted on by EppA to have the signal peptide removed.However, EppA can still remove signal peptides from non-glycosylated pilins.These findings indicate that there is a difference in the order of the posttranslational modifications of pilins and archaellins even though both are type IV pilin-like proteins.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada. 7ndb@queensu.ca.

ABSTRACT
Methanococcus maripaludis has two different surface appendages: type IV-like pili and archaella. Both structures are believed to be assembled using a bacterial type IV pilus mechanism. Each structure is composed of multiple subunits, either pilins or archaellins. Both pilins and archaellins are made initially as preproteins with type IV pilin-like signal peptides, which must be removed by a prepilin peptidase-like enzyme. This enzyme is FlaK for archaellins and EppA for pilins. In addition, both pilins and archaellins are modified with N-linked glycans. The archaellins possess an N-linked tetrasaccharide while the pilins have a pentasaccharide which consists of the archaellin tetrasaccharide but with an additional sugar, an unidentified hexose, attached to the linking sugar. In this report, we show that archaellins can be processed by FlaK in the absence of N-glycosylation and N-glycosylation can occur on archaellins that still retain their signal peptides. In contrast, pilins are not glycosylated unless they have been acted on by EppA to have the signal peptide removed. However, EppA can still remove signal peptides from non-glycosylated pilins. These findings indicate that there is a difference in the order of the posttranslational modifications of pilins and archaellins even though both are type IV pilin-like proteins.

No MeSH data available.


Related in: MedlinePlus

Alignment of the N-terminus region, including the signal peptide, of type IV pilin-like proteins of M. maripaludis.
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life-05-00085-f001: Alignment of the N-terminus region, including the signal peptide, of type IV pilin-like proteins of M. maripaludis.

Mentions: M. maripaludis has two prepilin peptidase-like enzymes. In addition to the one that processes archaellins, identified previously by Bardy and Jarrell [18] and designated FlaK, Szabo et al. [21] discovered EppA which was shown to process the pilins EpdA and EpdC. Both pilins and archaellins share significant amino acid sequence similarities in their signal peptides, including key conserved residues near the cleavage site itself (positions −1 to −3; Figure 1), and in the mature N-terminus [2,3,39].


Pilin Processing Follows a Different Temporal Route than That of Archaellins in Methanococcus maripaludis.

Nair DB, Jarrell KF - Life (Basel) (2015)

Alignment of the N-terminus region, including the signal peptide, of type IV pilin-like proteins of M. maripaludis.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4390842&req=5

life-05-00085-f001: Alignment of the N-terminus region, including the signal peptide, of type IV pilin-like proteins of M. maripaludis.
Mentions: M. maripaludis has two prepilin peptidase-like enzymes. In addition to the one that processes archaellins, identified previously by Bardy and Jarrell [18] and designated FlaK, Szabo et al. [21] discovered EppA which was shown to process the pilins EpdA and EpdC. Both pilins and archaellins share significant amino acid sequence similarities in their signal peptides, including key conserved residues near the cleavage site itself (positions −1 to −3; Figure 1), and in the mature N-terminus [2,3,39].

Bottom Line: In contrast, pilins are not glycosylated unless they have been acted on by EppA to have the signal peptide removed.However, EppA can still remove signal peptides from non-glycosylated pilins.These findings indicate that there is a difference in the order of the posttranslational modifications of pilins and archaellins even though both are type IV pilin-like proteins.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada. 7ndb@queensu.ca.

ABSTRACT
Methanococcus maripaludis has two different surface appendages: type IV-like pili and archaella. Both structures are believed to be assembled using a bacterial type IV pilus mechanism. Each structure is composed of multiple subunits, either pilins or archaellins. Both pilins and archaellins are made initially as preproteins with type IV pilin-like signal peptides, which must be removed by a prepilin peptidase-like enzyme. This enzyme is FlaK for archaellins and EppA for pilins. In addition, both pilins and archaellins are modified with N-linked glycans. The archaellins possess an N-linked tetrasaccharide while the pilins have a pentasaccharide which consists of the archaellin tetrasaccharide but with an additional sugar, an unidentified hexose, attached to the linking sugar. In this report, we show that archaellins can be processed by FlaK in the absence of N-glycosylation and N-glycosylation can occur on archaellins that still retain their signal peptides. In contrast, pilins are not glycosylated unless they have been acted on by EppA to have the signal peptide removed. However, EppA can still remove signal peptides from non-glycosylated pilins. These findings indicate that there is a difference in the order of the posttranslational modifications of pilins and archaellins even though both are type IV pilin-like proteins.

No MeSH data available.


Related in: MedlinePlus