subtilis and Ply500 in L. monocytogenes bacteriophage A500 [23, 25] and D-alanoyl-D-alanine carboxypeptidases [26]. The SH3_5 domain at the C-terminus was found in the putative lysins of Bacillus bacterial strains, Bacillus phages and Lactobacillus
phages (Figure 1a), suggesting that this domain is the cell wall binding domain. Biochemical characterization showed that the LysB4 endolysin was slightly alkalophilic, because activity was optimal at pH 8.0-10.0. It was also slightly thermophilic, with an optimal temperature of 50°C. The maximal lytic activity occurred in the absence of NaCl. This enzyme required a divalent metal ion, such as Zn2+ or Mn2+, for full enzymatic activity. A similar requirement for divalent cations was seen for Ply500 in L. monocytogenes GSK1210151A price bacteriophage A500 [23]. The other characterized L-alanoyl-D-glutamate peptidase, T5 endolysin requires Ca2+ instead of
Zn2+ or Mn2+ [24]. The requirement of Zn2+ or Mn2+ is supported by protein sequence analysis, because LysB4 has the three Zn2+-coordinating residues (His80, Asp87, His133) of Ply500, and the Zn2+-binding domain (SxHxxGxAxD) [22]. Endolysins are generally known to be highly specific against particular species {Selleck Anti-diabetic Compound Library|Selleck Antidiabetic Compound Library|Selleck Anti-diabetic Compound Library|Selleck Antidiabetic Compound Library|Selleckchem Anti-diabetic Compound Library|Selleckchem Antidiabetic Compound Library|Selleckchem Anti-diabetic Compound Library|Selleckchem Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|Anti-diabetic Compound Library|Antidiabetic Compound Library|buy Anti-diabetic Compound Library|Anti-diabetic Compound Library ic50|Anti-diabetic Compound Library price|Anti-diabetic Compound Library cost|Anti-diabetic Compound Library solubility dmso|Anti-diabetic Compound Library purchase|Anti-diabetic Compound Library manufacturer|Anti-diabetic Compound Library research buy|Anti-diabetic Compound Library order|Anti-diabetic Compound Library mouse|Anti-diabetic Compound Library chemical structure|Anti-diabetic Compound Library mw|Anti-diabetic Compound Library molecular weight|Anti-diabetic Compound Library datasheet|Anti-diabetic Compound Library supplier|Anti-diabetic Compound Library in vitro|Anti-diabetic Compound Library cell line|Anti-diabetic Compound Library concentration|Anti-diabetic Compound Library nmr|Anti-diabetic Compound Library in vivo|Anti-diabetic Compound Library clinical trial|Anti-diabetic Compound Library cell assay|Anti-diabetic Compound Library screening|Anti-diabetic Compound Library high throughput|buy Antidiabetic Compound Library|Antidiabetic Compound Library ic50|Antidiabetic Compound Library price|Antidiabetic Compound Library cost|Antidiabetic Compound Library solubility dmso|Antidiabetic Compound Library purchase|Antidiabetic Compound Library manufacturer|Antidiabetic Compound Library research buy|Antidiabetic Compound Library order|Antidiabetic Compound Library chemical structure|Antidiabetic Compound Library datasheet|Antidiabetic Compound Library supplier|Antidiabetic Compound Library in vitro|Antidiabetic Compound Library cell line|Antidiabetic Compound Library concentration|Antidiabetic Compound Library clinical trial|Antidiabetic Compound Library cell assay|Antidiabetic Compound Library screening|Antidiabetic Compound Library high throughput|Anti-diabetic Compound high throughput screening| of bacteria. However, LysB4 showed lytic activity against a broad range of bacterial species. LysB4 showed similar activity toward susceptible this website Gram-positive and Gram-negative bacteria, whereas other reported L-alanoyl-D-glutamate endopeptidases have a much narrower target host range [23]. LysB4 could lyse not only B. cereus strains but also other Gram-positive bacteria such as B. subtilis and L. monocytogenes strains. In addition, this enzyme also showed lytic activity toward Gram-negative bacteria when treated with EDTA. Most Gram-negative bacteria contain the Alγ type peptidoglycan, and Bacillus species and L. monocytogenes have the Alγ type cell wall as well [23, 24, 27, 28]. Thus, LysB4 probably targets Alγ type peptidoglycan. This relatively broad antibacterial spectrum of LysB4 was surprising, given the narrow host range of the bacteriophage B4. Bacteriophage B4 only targets
one strain of B. cereus (strain ATCC 10876) of five tested B. cereus strains and other Gram-positive bacterial species including L. monocytogenes strains, S. aureus, many and Ent. faecalis (Shin et al. unpublished). This suggests that there are more bacterial species with the LysB4 cell wall recognition site than those containing the bacteriophage B4 receptor. Therefore, further studies are needed to determine the moiety targeted by the LysB4 cell-wall binding SH3_5 domain. Conclusions LysB4 is the first characterized L-alanoyl-D-glutamate endopeptidase originating from a B. cereus bacteriophage. Although LysB4 has similar enzymatic and genetic properties to Ply500 from L. monocytogenes bacteriophage, LysB4 has broader spectrum and can lyse both Gram-positive and Gram-negative bacteria, including a number of foodborne pathogens.