Author: Karen Ann Cloud
Publisher:
ISBN:
Category :
Languages : en
Pages : 280
Book Description
Lytic Transglycosylases are Responsible for the Production of Peptidoglycan-derived Cytotoxin in Neisseria Gonorrhoeae
Lytic Transglycosylases
Author: Anna Isabell Weaver
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
The bacterial cell wall comprises a strong, covalently closed network of peptidoglycan (PG) strands. While PG synthesis is generally essential for bacterial survival, the cell wall is also by necessity a dynamic structure and undergoes constant degradation and remodeling by "autolysins," enzymes that break bonds within PG. One class of autolysin, the lytic transglycosylases (LTGs), cleaves the glycosidic linkages within PG strands. Despite LTGs having well-described biochemical properties, LTG redundancy and diversity have stymied understanding of their fundamental physiological roles. LTGs have been mostly assigned various non-essential, or poorly defined, pleiotropic functions and so there has been no clear evidence to explain why this extreme redundancy, usually indicating an essential function, is so widely conserved amongst diverse bacteria. The diarrheal pathogen Vibrio cholerae encodes eight known LTGs and inactivating single LTGs rarely generates a significant mutant phenotype from which to infer physiological importance. Therefore, rather than directly pursuing individual LTGs, we sought to explore the collective function of the entire enzymatic class by interrogating a mutant lacking all known LTGs. In doing so, we found that V. cholerae must retain at least one active LTG for survival and subsequently characterized the first truly essential role fulfilled by LTGs : clearance of PG debris from the periplasm which accumulates during normal cell wall expansion and remodeling, or during cell wall damage. Coincidentally, this addresses a fundamental question about how bacteria maintain the integrity of a dynamic cell wall through temporal separation of this LTG-mediated autolysis from synthesis, likely independent of previously hypothesized protein-protein interactions. By systematically re-introducing LTGs back into LTG-deficient mutants, we have also created a platform for empirically organizing diverse LTGs into functional families where previously they could only be categorized by their biochemistry. For example, one functional group includes LTGs that are specifically required for clearance of PG debris during septation and daughter cell separation. Another group likely contributes to the elusive, and now confirmed essential, function of releasing newly synthesized PG from the inner membrane. This platform is far from exhaustion and will continue to yield critical information about lytic transglycosylases and their relationship with cell wall homeostasis.
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
The bacterial cell wall comprises a strong, covalently closed network of peptidoglycan (PG) strands. While PG synthesis is generally essential for bacterial survival, the cell wall is also by necessity a dynamic structure and undergoes constant degradation and remodeling by "autolysins," enzymes that break bonds within PG. One class of autolysin, the lytic transglycosylases (LTGs), cleaves the glycosidic linkages within PG strands. Despite LTGs having well-described biochemical properties, LTG redundancy and diversity have stymied understanding of their fundamental physiological roles. LTGs have been mostly assigned various non-essential, or poorly defined, pleiotropic functions and so there has been no clear evidence to explain why this extreme redundancy, usually indicating an essential function, is so widely conserved amongst diverse bacteria. The diarrheal pathogen Vibrio cholerae encodes eight known LTGs and inactivating single LTGs rarely generates a significant mutant phenotype from which to infer physiological importance. Therefore, rather than directly pursuing individual LTGs, we sought to explore the collective function of the entire enzymatic class by interrogating a mutant lacking all known LTGs. In doing so, we found that V. cholerae must retain at least one active LTG for survival and subsequently characterized the first truly essential role fulfilled by LTGs : clearance of PG debris from the periplasm which accumulates during normal cell wall expansion and remodeling, or during cell wall damage. Coincidentally, this addresses a fundamental question about how bacteria maintain the integrity of a dynamic cell wall through temporal separation of this LTG-mediated autolysis from synthesis, likely independent of previously hypothesized protein-protein interactions. By systematically re-introducing LTGs back into LTG-deficient mutants, we have also created a platform for empirically organizing diverse LTGs into functional families where previously they could only be categorized by their biochemistry. For example, one functional group includes LTGs that are specifically required for clearance of PG debris during septation and daughter cell separation. Another group likely contributes to the elusive, and now confirmed essential, function of releasing newly synthesized PG from the inner membrane. This platform is far from exhaustion and will continue to yield critical information about lytic transglycosylases and their relationship with cell wall homeostasis.
Inhibition of Membrane-Bound Lytic Transglycosylase F (MltF) by Inhibitors of Lysozyme
Author: Kathryn Holland
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Inhibition of Membrane-Bound Lytic Transglycosylases A, B and F by Membrane-Bound Lysozyme Inhibitor of C-type Lysozyme
Author: Joseph Ciufo
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Peptidoglycan (PG) is an essential component of bacterial cells that forms a mesh-like sacculus that surrounds the cell. Lytic transglycosylases (LTs) are space-making enzymes that are essential for the cleavage of glycosidic linkages in the PG sacculus. This study proposes that the physiological function of the proteinaceous inhibitor, membrane-bound lysozyme inhibitor of C-type lysozyme (MliC) from P. aeruginosa, is to control LT activity from the same bacterium. This study examined the role of MliC as an inhibitor of the soluble-derivatives of membrane-bound lytic transglycosylases A (sMltA), B (sMltB) and F (sMltF). Inhibition of sMltA and sMltF was demonstrated in vitro at a 1:1 equivalent molar ratio (inhibitor: LT), and inhibition of sMltB was found at a 4:1 equivalent molar ratio using the turbidimetric assay. These results provide the first experimental evidence supporting the hypothesis that the true physiological function of MliC is to control the autolytic activity of LTs.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Peptidoglycan (PG) is an essential component of bacterial cells that forms a mesh-like sacculus that surrounds the cell. Lytic transglycosylases (LTs) are space-making enzymes that are essential for the cleavage of glycosidic linkages in the PG sacculus. This study proposes that the physiological function of the proteinaceous inhibitor, membrane-bound lysozyme inhibitor of C-type lysozyme (MliC) from P. aeruginosa, is to control LT activity from the same bacterium. This study examined the role of MliC as an inhibitor of the soluble-derivatives of membrane-bound lytic transglycosylases A (sMltA), B (sMltB) and F (sMltF). Inhibition of sMltA and sMltF was demonstrated in vitro at a 1:1 equivalent molar ratio (inhibitor: LT), and inhibition of sMltB was found at a 4:1 equivalent molar ratio using the turbidimetric assay. These results provide the first experimental evidence supporting the hypothesis that the true physiological function of MliC is to control the autolytic activity of LTs.
Structure and Reaction Mechanism of Lytic Transglycosylases
Author: Erik J. van Asselt
Publisher:
ISBN: 9789036711524
Category :
Languages : en
Pages : 173
Book Description
Publisher:
ISBN: 9789036711524
Category :
Languages : en
Pages : 173
Book Description
Bacterial Lytic Transglycosylases
Author: University of Guelph. Department of Chemistry and Biochemistry
Publisher:
ISBN: 9780494209400
Category :
Languages : en
Pages : 209
Book Description
Publisher:
ISBN: 9780494209400
Category :
Languages : en
Pages : 209
Book Description
Development of a Method to Generate a Soluble Substrate for Lytic Transglycosylases
Author: Adam L. Mark
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Investigating the Lytic Transglycosylases of Burkholderia Pseudomallei
Author: Christopher Jenkins
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Characterization of Family Three Lytic Transglycosylases from Pseudomonas Aeruginosa [microform]
Author: Neil Blackburn
Publisher: National Library of Canada = Bibliothèque nationale du Canada
ISBN: 9780612711785
Category :
Languages : en
Pages : 242
Book Description
Publisher: National Library of Canada = Bibliothèque nationale du Canada
ISBN: 9780612711785
Category :
Languages : en
Pages : 242
Book Description
Murein-metabolizing Enzymes from Escherichia Coli: The Lytic Transglycosylases
Author: Hendrik Engel
Publisher:
ISBN:
Category :
Languages : en
Pages : 113
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 113
Book Description