Protein secretion and outer membrane assembly in<i>Alphaproteobacteria</i>

Gatsos, Xenia; Perry, Andrew; Anwari, Khatira; Doležal, Pavel; Wolynec, P. Peter; Likić, Vladimir A; Purcell, Anthony W.; Buchanan, Susan K.; Lithgow, Trevor

doi:10.1111/j.1574-6976.2008.00130.x

Cited by 80 publications

(110 citation statements)

References 141 publications

Supporting

Mentioning

110

Contrasting

Order By: Relevance

“…Analysis of its sequence reveals the presence of a tetratricopeptide repeat profile. This profile appears in different proteins, among them a family of lipoproteins (InterPro IPR017689) that includes YfiO, involved in outer membrane assembly in E. coli (Gatsos et al, 2008), and ComL, which participates in DNA uptake and transformation in Neisseria gonorrhoeae (Fussenegger et al, 1997). However, OlpA has little sequence similarity with these two proteins, and homologues of OlpA seem to be restricted to Pseudomonas species.…”

Section: Discussionmentioning

confidence: 99%

Selection of hyperadherent mutants in Pseudomonas putida biofilms

et al. 2011

View full text Add to dashboard Cite

A number of genetic determinants required for bacterial colonization of solid surfaces and biofilm formation have been identified in different micro-organisms. There are fewer accounts of mutations that favour the transition to a sessile mode of life. Here we report the isolation of random transposon Pseudomonas putida KT2440 mutants showing increased biofilm formation, and the detailed characterization of one of them. This mutant exhibits a complex phenotype, including altered colony morphology, increased production of extracellular polymeric substances and enhanced swarming motility, along with the formation of denser and more complex biofilms than the parental strain. Sequence analysis revealed that the pleiotropic phenotype exhibited by the mutant resulted from the accumulation of two mutations: a transposon insertion, which disrupted a predicted outer membrane lipoprotein, and a point mutation in lapG, a gene involved in the turnover of the large adhesin LapA. The contribution of each alteration to the phenotype and the possibility that prolonged sessile growth results in the selection of hyperadherent mutants are discussed. INTRODUCTIONThe development of a multicellular community associated with a surface and surrounded by an exopolymeric matrix, referred to as a biofilm, is common to a variety of bacteria under different environmental conditions. Biofilm formation has received increasing attention due to its importance in medicine, since biofilm populations are considered relevant to chronic infection, and are more resistant to the action of antibiotics and biocidals than planktonic populations (Anderson & O'Toole, 2008;Høiby et al., 2010). Biofilm development is also relevant in industrial settings and in the design of bioreactors (Nicolella et al., 2000;Singh et al., 2006). Genetic determinants that play a role in biofilm formation have been unravelled in different bacterial species, and environmental and cellular signals that influence this process have also been described. These include iron availability, quorum sensing, and the intracellular secondary messenger cyclic di-GMP (Banin et al., 2006;Patriquin et al., 2008;Ueda & Wood, 2009;Coenye, 2010). Changes in the levels of cyclic di-GMP correlate with phenotypic changes associated with virulence, motility, colony morphology, production of exopolysaccharides, and the transition between planktonic and sessile lifestyles (Hengge, 2009; Römling & Simm, 2009, and references therein). Changes in the expression of different functions are also associated with one or the other lifestyle; in Pseudomonas aeruginosa and Pseudomonas putida, for example, differential expression of flagellar components has been observed when comparing planktonic and biofilm populations, and even during the various stages of biofilm development (Sauer & Camper, 2001;Sauer et al., 2002;Toutain et al., 2007). In the former organism, swarming motility and surface attachment are inversely regulated through a pathway that involves BifA, a cyclic-di-GMP phosphodiesterase, and the membra...

show abstract

Section: Discussionmentioning

confidence: 99%

Selection of hyperadherent mutants in Pseudomonas putida biofilms

et al. 2011

View full text Add to dashboard Cite

show abstract

“…Compared with E. coli, the Caulobacter complex lacks the lipoprotein BamC (Gatsos et al, 2008), while the N. meningitidis complex lacks the lipoprotein BamB and contains the additional protein RmpM (Volokhina et al, 2009). The C terminus of RmpM is predicted to bind peptidoglycan and is similar to the C-terminal region of OmpA, but RmpM lacks the Nterminal b-barrel-forming region of OmpA (Grizot & Buchanan, 2004).…”

Section: Discussionmentioning

confidence: 99%

“…Within the BAM complex, BamB interacts directly with BamA, while BamC, D and E depend on each other for interaction with BamA (Malinverni et al, 2006;Sklar et al, 2007;Vuong et al, 2008). Because Caulobacter lacks a BamC homologue (Gatsos et al, 2008), we wondered if BamE (and BamD) could still associate with BamA.…”

Section: Caulobacter Bame Associates With Other Proteins Implicated Imentioning

confidence: 99%

The BAM complex subunit BamE (SmpA) is required for membrane integrity, stalk growth and normal levels of outer membrane β-barrel proteins in Caulobacter crescentus

2010

View full text Add to dashboard Cite

The outer membrane of Gram-negative bacteria is an essential compartment containing a specific complement of lipids and proteins that constitute a protective, selective permeability barrier. Outer membrane β-barrel proteins are assembled into the membrane by the essential hetero-oligomeric BAM complex, which contains the lipoprotein BamE. We have identified a homologue of BamE, encoded by CC1365, which is located in the outer membrane of the stalked alpha-proteobacterium Caulobacter crescentus. BamE associates with proteins whose homologues in other bacteria are known to participate in outer membrane protein assembly: BamA (CC1915), BamB (CC1653) and BamD (CC1984). Caulobacter cells lacking BamE grow slowly in rich medium and are hypersensitive to anionic detergents, some antibiotics and heat exposure, which suggest that the membrane integrity of the mutant is compromised. Membranes of the ΔbamE mutant have normal amounts of the outer membrane protein RsaF, a TolC homologue, but are deficient in CpaC*, an aggregated form of the outer membrane secretin for type IV pili. ΔbamE membranes also contain greatly reduced amounts of three TonB-dependent receptors that are abundant in wild-type cells. Cells lacking BamE have short stalks and are delayed in stalk outgrowth during the cell cycle. Based on these findings, we propose that Caulobacter BamE participates in the assembly of outer membrane β-barrel proteins, including one or more substrates required for the initiation of stalk biogenesis.

show abstract

“…22,23 Although discrepancies exist in the literature, BAM complex proteins have recently been renamed. 22,24,25 YfgL (BamB) is an OM lipoprotein, which is anchored to the periplasmic face of the OM 22 and displays a role in membrane permeability and antibiotic resistance of E. coli and S. enterica serovar Enteritidis. 26,27 A previous study demonstrated that the Salmonella YfgL lipoprotein is essential for expression of the type-III secretion system.…”

Section: Introductionmentioning

confidence: 99%

TheKlebsiella pneumoniaeYfgL (BamB) lipoprotein contributes to outer membrane protein biogenesis, type-1 fimbriae expression, anti-phagocytosis, andin vivovirulence

et al. 2016

View full text Add to dashboard Cite

Klebsiella pneumoniae is an opportunistic pathogen that causes several kinds of infections, including pneumonia, bacteremia, urinary tract infection and community-acquired pyogenic liver abscess (PLA). Adhesion is the critical first step in the infection process. Our previous work demonstrated that the transcellular translocation is exploited by K. pneumoniae strains to migrate from the gut flora into other tissues, resulting in systemic infections. However, the initial stages of K. pneumoniae infection remain unclear. In this study, we demonstrated that a K. pneumoniae strain deleted for yfgL (bamB) exhibited reduced adherence to and invasion of host cells; changed biogenesis of major b-barrel outer membrane proteins; decreased transcriptional expression of type-1 fimbriae; and increased susceptibility to vancomycin and erythromycin. The yfgL deletion mutant also had reduced ability to against neutrophil phagocytosis; exhibited decreased induction of host IL-6 production; and was profoundly attenuated for virulence in a K. pneumoniae model of bacteremia. Thus, the K. pneumoniae YfgL lipoprotein mediates in outer membrane proteins biogenesis and is crucial for anti-phagocytosis and survival in vivo. These data provide a new insight for K. pneumoniae attachment and such knowledge could facilitate preventive therapies or alternative therapies against K. pneumoniae.

show abstract

Protein secretion and outer membrane assembly inAlphaproteobacteria

Cited by 80 publications

References 141 publications

Selection of hyperadherent mutants in Pseudomonas putida biofilms

Selection of hyperadherent mutants in Pseudomonas putida biofilms

The BAM complex subunit BamE (SmpA) is required for membrane integrity, stalk growth and normal levels of outer membrane β-barrel proteins in Caulobacter crescentus

TheKlebsiella pneumoniaeYfgL (BamB) lipoprotein contributes to outer membrane protein biogenesis, type-1 fimbriae expression, anti-phagocytosis, andin vivovirulence

Contact Info

Product

Resources

About