Sensitivity of <i>L</i>. <i>plantarum</i> W903 derivatives harboring hybrid <i>IIC/IID</i> or <i>IIC/IID</i> and <i>pedB</i> to pediocin PA-1.

Sensitivity of L. plantarum W903 derivatives harboring hybrid IIC/IID or IIC/IID and pedB to pediocin PA-1.</p

Both IIC and IID Components of Mannose Phosphotransferase System Are Involved in the Specific Recognition between Immunity Protein PedB and Bacteriocin-Receptor Complex - Fig 1

(A) Construction of the L. plantarum mutant strain W903. Genes are represented by arrows, promoters are indicated by triangles, and the internal fragment of IIAB is represented by a gray solid box. Chromosomal DNA is represented by black lines, plasmid DNA is represented by green lines, and the red arrow indicates the PCR products amplified using the forward primer EmrF and the reverse primer MptAR. (B) Sensitivity of L. plantarum WQ0815 (left) and L. plantarum W903 (right) to pediocin PA-1.</p

DataSheet1_Tunable Thermo-Responsive Properties of Hydroxybutyl Chitosan Oligosaccharide.docx

In this study, a simple method was used to synthesize novel thermosensitive hydroxybutyl chitosan oligosaccharide (HBCOS) by introducing hydroxybutyl groups to C6–OH of chitosan oligosaccharide (COS) chain. The variation in light scattering demonstrated that HBCOS had good thermosensitive properties and the particle size of HBCOS changed from 2.21–3.58 to 281.23–4,162.40 nm as the temperature increased to a critical temperature (LCST). The LCST of HBCOS (10 mg/ml) decreased from 56.25°C to 40.2°C as the degrees of substitution (DSs) increased from 2.96 to 4.66. The LCST of HBCOS with a DS of 4.66 decreased to 33.5°C and 30°C as the HBCOS and NaCl concentrations increased to 50 mg/ml and 4% (w/v), respectively. Variable-temperature FTIR spectroscopy confirmed that dehydration of hydrophobic chains and the transition of hydrogen bonds were the driving forces for the phase transition of HBCOS. Moreover, HBCOS was not cytotoxic at different concentrations. This work generated a novel thermosensitive HBCOS with tunable thermoresponsive properties and excellent biocompatibility, which may be a potential nanocarrier for the biomedical application.</p

Bacterial strains and plasmids used in this study.

Bacterial strains and plasmids used in this study.</p

Both IIC and IID Components of Mannose Phosphotransferase System Are Involved in the Specific Recognition between Immunity Protein PedB and Bacteriocin-Receptor Complex

<div><p>Upon exposure to exogenous pediocin-like bacteriocins, immunity proteins specifically bind to the target receptor of the mannose phosphotransferase system components (man-PTS IIC and IID), therefore preventing bacterial cell death. However, the specific recognition of immunity proteins and its associated target receptors remains poorly understood. In this study, we constructed hybrid receptors to identify the domains of IIC and/or IID recognized by the immunity protein PedB, which confers immunity to pediocin PA-1. Using <i>Lactobacillus plantarum</i> man-PTS EII mutant W903, the IICD components of four pediocin PA-1-sensitive strains (<i>L</i>. <i>plantarum</i> WQ0815, <i>Leuconostoc mesenteroides</i> 05–43, <i>Lactobacillus salivarius</i> REN and <i>Lactobacillus acidophilus</i> 05–172) were respectively co-expressed with the immunity protein PedB. Well-diffusions assays showed that only the complex formed by LpIICD from <i>L</i>. <i>plantarum</i> WQ0815 with pediocin PA-1 could be recognized by PedB. In addition, a two-step PCR approach was used to construct hybrid receptors by combining LpIIC or LpIID recognized by PedB with the other three heterologous IID or IIC compounds unrecognized by PedB, respectively. The results showed that all six hybrid receptors were recognized by pediocin PA-1. However, when IIC or IID of <i>L</i>. <i>plantarum</i> WQ0815 was replaced with any corresponding IIC or IID component from <i>L</i>. <i>mesenteroides</i> 05–43, <i>L</i>. <i>salivarius</i> REN and <i>L</i>. <i>acidophilus</i> 05–172, all the hybrid receptors could not be recognized by PedB. Taken altogether, we concluded that both IIC and IID components of the mannose phosphotransferase system play an important role in the specific recognition between the bacteriocin-receptor complex and the immunity protein PedB.</p></div

Both IIC and IID Components of Mannose Phosphotransferase System Are Involved in the Specific Recognition between Immunity Protein PedB and Bacteriocin-Receptor Complex - Fig 4

<p><b>Multiple sequence alignments (A) and phylogenetic clustering (B) of IIC and IID proteins from <i>L</i>. <i>plantarum</i>, <i>L</i>. <i>mesenteroides</i>, <i>L</i>. <i>salivarius</i>, <i>L</i>. <i>acidophilus</i> and <i>P</i>. <i>acidilactici</i>.</b> Transmembrane helix (TMhelix), extracellular and intracellular regions were determined by using TMHMM v. 2.0 software. An asterisk, two dots, and one dot indicated decreasing degrees of conservation. The conserved motifs GGQGxxG and GG[D/K]FxxxG in the extracellular loop region are indicated by a grey background. The residues from <i>L</i>. <i>plantarum</i> and <i>P</i>. <i>acidilactici</i> in the intracellular regions are indicated by boxes. Sequence alignments and phylogenetic trees were constructed by using MUSCLE v. 3.8.31 software with default settings (<a href="http://www.ebi.ac.uk/Tools/msa/muscle/" target="_blank">http://www.ebi.ac.uk/Tools/msa/muscle/</a>) [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0164973#pone.0164973.ref027" target="_blank">27</a>].</p

Sensitivity of <i>L</i>. <i>plantarum</i> W903 derivatives harboring gene <i>IICD</i> or <i>IICD</i> and <i>pedB</i> to pediocin PA-1.

<p>Sensitivity of <i>L</i>. <i>plantarum</i> W903 derivatives harboring gene <i>IICD</i> or <i>IICD</i> and <i>pedB</i> to pediocin PA-1.</p

PCR primers for amplifying genes <i>IIC</i> and <i>IID</i>.

<p>PCR primers for amplifying genes <i>IIC</i> and <i>IID</i>.</p

Outline of the cloning procedure.

<p>Outline of the cloning procedure.</p

Differentially expressed proteins in human colostral whey.

Differentially expressed proteins in human colostral whey.</p