[Deficiency in N-acetylglucosamine transport affects the sporulation process and increases the hemolytic activity of the S-layer protein in Lysinibacillus sphaericus ASB13052].

Lysinibacillus sphaericus is a bacterium that, along with Bacillus thuringiensis var. israelensis, is considered the best biological insecticide for controlling mosquito larvae and an eco-friendly alternative to chemical insecticides. It depends on peptidic molecules such as N-acetylglucosamine to obtain carbon sources and possesses a phosphotransferase system (PTS) for their incorporation.

Surface layer proteins in species of the family Lactobacillaceae.

The S-layer or surface layer protein (SLP) is the most ancient biological envelope, highly conserved in several Bacteria and Archaea. In lactic acid bacteria (LAB), SLP is only found in species belonging to the Lactobacillaceae family, many of them considered probiotic microorganisms. New reclassification of members within the Lactobacillaceae family (International Journal of Systematic and Evolutionary Microbiology, 2020, 70, 2782) and newly sequenced genomes demands an updated revision on SLP genes and domain organization.

Lactic acid production using cheese whey based medium in a stirred tank reactor by a ccpA mutant of Lacticaseibacillus casei.

In lactobacilli, CcpA is known to modulate the expression of genes involved in sugar metabolism, stress response and aerobic adaptation. This study aimed to evaluate a ccpA mutant of Lacticaseibacillus casei BL23 to increase lactic acid production using cheese whey. The ccpA derivative (BL71) showed better growth than the L.

Development of an Antigen Delivery Platform Using Decorated With Heterologous Proteins: A Sheep in Wolf's Clothing Story.

S-layers are bacterial structures present on the surface of several Gram-positive and Gram-negative bacteria that play a role in bacterial protection. In ( ATCC 4356), the S-layer is mainly composed of the protein SlpA. A tandem of two copies of the protein domain SLP-A (pfam: 03217) was identified at the C-terminal of SlpA, being this double SLP-A protein domain (in short dSLP-A) necessary and sufficient for the association of the protein to the cell wall.

Strategies to display heterologous proteins on the cell surface of lactic acid bacteria using as anchor the C-terminal domain of Lactobacillus acidophilus SlpA.

The surface-layer (S-layer) protein of Lactobacillus acidophilus is a crystalline array of self-assembling subunits, non-covalently bound to the most outer cell wall envelope, which constitutes up to 20% of the total cell protein content. These attributes make S-layer proteins an excellent anchor for the development of microbial cell-surface display systems. In L.

Exploring lectin-like activity of the S-layer protein of Lactobacillus acidophilus ATCC 4356.

The surface layer (S-layer) protein of Lactobacillus acidophilus is a crystalline array of self-assembling, proteinaceous subunits non-covalently bound to the outmost bacterial cell wall envelope and is involved in the adherence of bacteria to host cells. We have previously described that the S-layer protein of L. acidophilus possesses anti-viral and anti-bacterial properties.

Draft Genome Sequence of ATCC 12046.

is a lactic acid bacterium used traditionally in the dairy industry, especially in the manufacture of cheeses. We present here the 2,141,841-bp draft genome sequence of strain ATCC 12046, a potential starter strain for improving cheese production.

S-layer proteins from Lactobacillus sp. inhibit bacterial infection by blockage of DC-SIGN cell receptor.

Many species of Lactobacillus sp. possess Surface(s) layer proteins in their envelope. Among other important characteristics S-layer from Lactobacillus acidophilus binds to the cellular receptor DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin; CD209), which is involved in adhesion and infection of several families of bacteria.

Influence of osmotic stress on the profile and gene expression of surface layer proteins in Lactobacillus acidophilus ATCC 4356.

In this work, we studied the role of surface layer (S-layer) proteins in the adaptation of Lactobacillus acidophilus ATCC 4356 to the osmotic stress generated by high salt. The amounts of the predominant and the auxiliary S-layer proteins SlpA and SlpX were strongly influenced by the growth phase and high-salt conditions (0.6 M NaCl).

Draft Genome Sequence of the Probiotic Strain Lactobacillus acidophilus ATCC 4356.

We present the 1,956,699-bp draft genome sequence of Lactobacillus acidophilus strain ATCC 4356. Comparative genomic analysis revealed 99.96% similarity with L.

Contribution of S-layer proteins to the mosquitocidal activity of Lysinibacillus sphaericus.

Lysinibacillus sphaericus strains belonging the antigenic group H5a5b produce spores with larvicidal activity against larvae of Culex mosquitoes. C7, a new isolated strain, which presents similar biochemical characteristics and Bin toxins in their spores as the reference strain 2362, was, however, more active against larvae of Culex mosquitoes. The contribution of the surface layer protein (S-layer) to this behaviour was envisaged since this envelope protein has been implicated in the pathogenicity of several bacilli, and we had previously reported its association to spores.

Osmotic stress adaptation in Lactobacillus casei BL23 leads to structural changes in the cell wall polymer lipoteichoic acid.

The probiotic Gram-positive bacterium Lactobacillus casei BL23 is naturally confronted with salt-stress habitats. It has been previously reported that growth in high-salt medium, containing 0.8 M NaCl, leads to modifications in the cell envelope of this bacterium.

"A la recherche" of functions for the spore protein SASP-E from Bacillus subtilis.

We previously observed that Bacillus subtilis spores from sspE mutants presented a lower germination capacity in media containing high salt concentrations (0.9 M NaCl). This deficiency was attributed to the absence of SASP-E (gamma-type small-acid-soluble protein), rich in osmocompatible amino acids released by degradation.

S-layer proteins of Lactobacillus acidophilus inhibits JUNV infection.

It has been previously described that S-layer binds to the C-type lectin DC-specific ICAM-3-grabbing nonintegrin (DC-SIGN, CD209). It was also shown that DC-SIGN is a cell-surface adhesion factor that enhances viral entry of several virus families. Among those, Junin virus (JUNV) entry is enhanced in cells expressing DC-SIGN and for that reason surface-layer protein (S-layer) of Lactobacillus acidophilus ATCC 4365 was evaluated as a possible JUNV inhibitor.

Metal biosorption by surface-layer proteins from Bacillus species.

Bacillus species have been involved in metal association as biosorbents, but there is not a clear understanding of this chelating property. In order to evaluate this metal chelating capacity, cultures and spores from Grampositive bacteria of species either able or unable to produce surface layer proteins (S-layers) were analyzed for their capacity of copper biosorption. Only those endowed of S-layers, like Bacillus sphaericus and B.

New method for electroporation of Lactobacillus species grown in high salt.

We here describe a new method for electroporation of Lactobacillus species, obligately homofermentative and facultatively heterofermentative, based on the cell-wall weakening resulting from growth in high-salt media. For L. casei, optimum transformation efficiency of up to 10(5) transformants per microgram of plasmid DNA was achieved following growth in the presence of 0.

Synergistic effects of the Lactobacillus acidophilus surface layer and nisin on bacterial growth.

We have previously described a murein hydrolase activity for the surface layer (S-layer) of Lactobacillus acidophilus ATCC 4356. Here we show that, in combination with nisin, this S-layer acts synergistically to inhibit the growth of pathogenic Gram-negative Salmonella enterica and potential pathogenic Gram-positive bacteria, Staphylococcus aureus and Bacillus cereus. In addition, bacteriolytic effects were observed for the Gram-positive species tested.

High salt stress in Bacillus subtilis: involvement of PBP4* as a peptidoglycan hydrolase.

The study was focused on the role of the penicillin binding protein PBP4* of Bacillus subtilis during growth in high salinity rich media. Using pbpE-lacZ fusion, we found that transcription of the pbpE gene is induced in stationary phase and by increased salinity. This increase was also corroborated at the translation level for PBP4* by western blot.

Murein hydrolase activity in the surface layer of Lactobacillus acidophilus ATCC 4356.

We describe a new enzymatic functionality for the surface layer (S-layer) of Lactobacillus acidophilus ATCC 4356, namely, an endopeptidase activity against the cell wall of Salmonella enterica serovar Newport, assayed via zymograms and identified by Western blotting. Based on amino acid sequence comparisons, the hydrolase activity was predicted to be located at the C terminus. Subsequent cloning and expression of the C-terminal domain in Bacillus subtilis resulted in the functional verification of the enzymatic activity.

Effect of glutamate synthase (GOGAT) activity on Bacillus subtilis spore properties.

The role of glutamate as osmoprotector was investigated through the study of a mutation in its biosynthetic pathway. A glt::Tn917-lacZ-cat insertion mutant (N1) conferring glutamate auxotrophy and enhanced beta-galactosidase expression on high-salt media was selected. Co-transformation experiments and PCR analysis allowed locating the insertion into the gltB gene corresponding to the small unit of the glutamate synthase (GOGAT).