Limits...
Antibacterial properties of Acinetobacter baumannii phage Abp1 endolysin (PlyAB1).

Huang G, Shen X, Gong Y, Dong Z, Zhao X, Shen W, Wang J, Hu F, Peng Y - BMC Infect. Dis. (2014)

Bottom Line: Acinetobacter baumannii has emerged as one of the most important hospital-acquired pathogens in the world, because of its resistance to almost all available antibiotic drugs.These isolates were shown to belong to different ST clones by multilocus sequence typing.The results presented here show that PlyAB1 has potential as an antibiotic against drug-resistant A. baumannii.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, Southwest Hospital, Third Military Medical University, Chongqing, China. haitao3140@sina.com.

ABSTRACT

Background: Acinetobacter baumannii has emerged as one of the most important hospital-acquired pathogens in the world, because of its resistance to almost all available antibiotic drugs. Endolysins from phages are attracting increasing interest as potential antimicrobial agents, especially for drug-resistant bacteria. We previously isolated and characterized Abp1, a virulent phage targeting the multidrug-resistant A. baumannii strain, AB1.

Methods: To evaluate the antimicrobial potential of endolysin from the Abp1 phage, the endolysin gene plyAB1 was cloned and over-expressed in Escherichia coli, and the lytic activity of the recombinant protein (PlyAB1) was tested by turbidity assessment and bacteria counting assays.

Results: PlyAB1 exhibits a marked lytic activity against A. baumannii AB1, as shown by a decrease in the number of live bacteria following treatment with the enzyme. Moreover, PlyAB1 displayed a highly specific lytic effect against all of the 48 hospital-derived pandrug-resistant A. baumannii isolates that were tested. These isolates were shown to belong to different ST clones by multilocus sequence typing.

Conclusions: The results presented here show that PlyAB1 has potential as an antibiotic against drug-resistant A. baumannii.

Show MeSH

Related in: MedlinePlus

Sequence analysis of PlyAB1. (A) Locations of five mutations between PlyAB1 and LysAB2 shown by sequence alignment. (B) Analysis of the tertiary structure of PlyAB1 from the online SWISS-MODEL server. Five mutants are shown in the model: amino acids 33 (yellow), 41 (orange), 96 (green), 100 (red), and 103 (blue). (C) Visualization of the conserved domain (magenta) of PlyAB1. Three mutations (amino acids 96, 100, and 103) are located in the conserved domain.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4274762&req=5

Fig1: Sequence analysis of PlyAB1. (A) Locations of five mutations between PlyAB1 and LysAB2 shown by sequence alignment. (B) Analysis of the tertiary structure of PlyAB1 from the online SWISS-MODEL server. Five mutants are shown in the model: amino acids 33 (yellow), 41 (orange), 96 (green), 100 (red), and 103 (blue). (C) Visualization of the conserved domain (magenta) of PlyAB1. Three mutations (amino acids 96, 100, and 103) are located in the conserved domain.

Mentions: ORF50 of the A. baumannii phage Abp1 was predicted to be the putative endolysin by Blastp. The Pfam database reveals that it contains a conserved domain known as glycoside hydrolase family 19. Glycoside hydrolase family 19 comprises enzymes with only one known activity, that is, catalyzing the hydrolysis of beta-1,4-N-acetyl-D-glucosamine linkages [16]. We named the orf50 gene of Abp1, plyAB1. PlyAB1 encodes a 185 amino acid protein, of which amino acid positions 79 to 128 comprise the conserved domain. In spite of the high sequence similarity between PlyAB1 and LysAB2 [17], five mutations exist between them, three of which are located in the conserved domain (FigureĀ 1).Figure 1


Antibacterial properties of Acinetobacter baumannii phage Abp1 endolysin (PlyAB1).

Huang G, Shen X, Gong Y, Dong Z, Zhao X, Shen W, Wang J, Hu F, Peng Y - BMC Infect. Dis. (2014)

Sequence analysis of PlyAB1. (A) Locations of five mutations between PlyAB1 and LysAB2 shown by sequence alignment. (B) Analysis of the tertiary structure of PlyAB1 from the online SWISS-MODEL server. Five mutants are shown in the model: amino acids 33 (yellow), 41 (orange), 96 (green), 100 (red), and 103 (blue). (C) Visualization of the conserved domain (magenta) of PlyAB1. Three mutations (amino acids 96, 100, and 103) are located in the conserved domain.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4274762&req=5

Fig1: Sequence analysis of PlyAB1. (A) Locations of five mutations between PlyAB1 and LysAB2 shown by sequence alignment. (B) Analysis of the tertiary structure of PlyAB1 from the online SWISS-MODEL server. Five mutants are shown in the model: amino acids 33 (yellow), 41 (orange), 96 (green), 100 (red), and 103 (blue). (C) Visualization of the conserved domain (magenta) of PlyAB1. Three mutations (amino acids 96, 100, and 103) are located in the conserved domain.
Mentions: ORF50 of the A. baumannii phage Abp1 was predicted to be the putative endolysin by Blastp. The Pfam database reveals that it contains a conserved domain known as glycoside hydrolase family 19. Glycoside hydrolase family 19 comprises enzymes with only one known activity, that is, catalyzing the hydrolysis of beta-1,4-N-acetyl-D-glucosamine linkages [16]. We named the orf50 gene of Abp1, plyAB1. PlyAB1 encodes a 185 amino acid protein, of which amino acid positions 79 to 128 comprise the conserved domain. In spite of the high sequence similarity between PlyAB1 and LysAB2 [17], five mutations exist between them, three of which are located in the conserved domain (FigureĀ 1).Figure 1

Bottom Line: Acinetobacter baumannii has emerged as one of the most important hospital-acquired pathogens in the world, because of its resistance to almost all available antibiotic drugs.These isolates were shown to belong to different ST clones by multilocus sequence typing.The results presented here show that PlyAB1 has potential as an antibiotic against drug-resistant A. baumannii.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burn Research, Southwest Hospital, Third Military Medical University, Chongqing, China. haitao3140@sina.com.

ABSTRACT

Background: Acinetobacter baumannii has emerged as one of the most important hospital-acquired pathogens in the world, because of its resistance to almost all available antibiotic drugs. Endolysins from phages are attracting increasing interest as potential antimicrobial agents, especially for drug-resistant bacteria. We previously isolated and characterized Abp1, a virulent phage targeting the multidrug-resistant A. baumannii strain, AB1.

Methods: To evaluate the antimicrobial potential of endolysin from the Abp1 phage, the endolysin gene plyAB1 was cloned and over-expressed in Escherichia coli, and the lytic activity of the recombinant protein (PlyAB1) was tested by turbidity assessment and bacteria counting assays.

Results: PlyAB1 exhibits a marked lytic activity against A. baumannii AB1, as shown by a decrease in the number of live bacteria following treatment with the enzyme. Moreover, PlyAB1 displayed a highly specific lytic effect against all of the 48 hospital-derived pandrug-resistant A. baumannii isolates that were tested. These isolates were shown to belong to different ST clones by multilocus sequence typing.

Conclusions: The results presented here show that PlyAB1 has potential as an antibiotic against drug-resistant A. baumannii.

Show MeSH
Related in: MedlinePlus