Deletion of Rap-phosphatases for quorum sensing control in Bacillus and its effect on surfactin production.

The complex regulatory network in Bacillus, known as quorum sensing, offers many opportunities to modify bacterial gene expression and hence to control bioprocesses. One target regulated by this mechanism is the activity of the P promoter, which is engaged in the formation of lipopeptide surfactin. It was hypothesised that deletion of rapC, rapF and rapH, encoding for prominent Rap-phosphatases known to affect P activity, would enhance surfactin production.

Surfactin Shows Relatively Low Antimicrobial Activity against and Other Bacterial Model Organisms in the Absence of Synergistic Metabolites.

Surfactin is described as a powerful biosurfactant and is natively produced by Bacillus subtilis in notable quantities. Among other industrially relevant characteristics, antimicrobial properties have been attributed to surfactin-producing Bacillus isolates. To investigate this property, stress approaches were carried out with biotechnologically established strains of Corynebacterium glutamicum, Bacillus subtilis, Escherichia coli and Pseudomonas putida with the highest possible amounts of surfactin.

Modeling the time course of ComX: towards molecular process control for Bacillus wild-type cultivations.

Wild-type cultivations are of invaluable relevance for industrial biotechnology when it comes to the agricultural or food sector. Here, genetic engineering is hardly applicable due to legal barriers and consumer's demand for GMO-free products. An important pillar for wild-type cultivations displays the genus Bacillus.

Expression of degQ gene and its effect on lipopeptide production as well as formation of secretory proteases in Bacillus subtilis strains.

Bacillus subtilis is described as a promising production strain for lipopeptides. In the case of B. subtilis strains JABs24 and DSM10 , surfactin and plipastatin are produced.

Influence of B. subtilis 3NA mutations in spo0A and abrB on surfactin production in B. subtilis 168.

Background: Bacillus subtilis is a well-established host for a variety of bioproduction processes, with much interest focused on the production of biosurfactants such as the cyclic lipopeptide surfactin. Surfactin production is tightly intertwined with quorum sensing and regulatory cell differentiation processes. As previous studies have shown, a non-sporulating B.

Bacillus subtilis High Cell Density Fermentation Using a Sporulation-Deficient Strain for the Production of Surfactin.

Bacillus subtilis 3NA is a strain capable of reaching high cell densities. A surfactin producing sfp variant of this strain, named JABs32, was utilized in fed-batch cultivation processes. Both a glucose and an ammonia solution were fed to set a steady growth rate μ of 0.

Evaluation of an oxygen-dependent self-inducible surfactin synthesis in B. subtilis by substitution of native promoter P by anaerobically active P and P.

A novel approach targeting self-inducible surfactin synthesis under oxygen-limited conditions is presented. Because both the nitrate (NarGHI) and nitrite (NasDE) reductase are highly expressed during anaerobic growth of B. subtilis, the native promoter P of the surfactin operon in strain B.

Draft Genome Sequence of the Type Strain Bacillus subtilis subsp. DSM10.

The subsp. type strain DSM10 has been used as a reference in various studies. However, detailed information about the genome has not been available.

Towards the Anaerobic Production of Surfactin Using .

The anaerobic growth of to synthesize surfactin poses an alternative strategy to conventional aerobic cultivations. In general, the strong foam formation observed during aerobic processes represents a major obstacle. Anaerobic processes have, amongst others, the distinct advantage that the total bioreactor volume can be exploited as foaming does not occur.

Bacillus velezensis UTB96 Is an Antifungal Soil Isolate with a Reduced Genome Size Compared to That of Bacillus velezensis FZB42.

UTB96 was isolated from soil based on its antifungal activity. Whole-genome sequencing of strain UTB96 provided further information about its secondary metabolite gene clusters. Compared to the well-known strain FZB42, UTB96 lacks an IS element and a type I restriction endonuclease.

Evaluation of surfactin synthesis in a genome reduced Bacillus subtilis strain.

Strain engineering is often a method of choice towards increasing the yields of the biosurfactant surfactin which is naturally synthesized by many Bacillus spp., most notably Bacillus subtilis. In the current study, a genome reduced B.

The Operon Encodes a Utilization System for the Raffinose Family of Oligosaccharides in .

is a heterotrophic soil bacterium that hydrolyzes different polysaccharides mainly found in the decomposed plants. These carbohydrates are mainly cellulose, hemicellulose, and the raffinose family of oligosaccharides (RFOs). RFOs are soluble α-galactosides, such as raffinose, stachyose, and verbascose, that rank second only after sucrose in abundance.

Phosphosugar Stress in Bacillus subtilis: Intracellular Accumulation of Mannose 6-Phosphate Derepressed the Operon from Repression by GlcR.

phosphorylates sugars during or after their transport into the cell. Perturbation in the conversion of intracellular phosphosugars to the central carbon metabolites and accumulation of phosphosugars can impose stress on the cells. In this study, we investigated the effect of phosphosugar stress on Preliminary experiments indicated that the nonmetabolizable analogs of glucose were unable to impose stress on In contrast, deletion of encoding mannose 6-phosphate isomerase (responsible for conversion of mannose 6-phosphate to fructose 6-phosphate) resulted in growth arrest and bulged cell shape in the medium containing mannose.

Cross Talk among Transporters of the Phosphoenolpyruvate-Dependent Phosphotransferase System in Bacillus subtilis.

The phosphoenolpyruvate-dependent phosphotransferase system (PTS) is the main carbohydrate uptake system in A typical PTS consists of two general proteins, enzyme I (EI) and a histidine-containing protein (HPr), as well as a specific carbohydrate transporter (or enzyme II [EII]), all of which transfer the phosphoryl group from phosphoenolpyruvate to the transported carbohydrate. The specific PTS transporters are formed by multidomain proteins or single-domain subunits. These domains are domain C (EIIC), the transmembrane channel for the carbohydrate transport; domain B (EIIB), the membrane-bound domain responsible for phosphorylation of the carbohydrate; and domain A (EIIA), the mediator between HPr(H15∼P) and EIIB.

Role of the ganSPQAB Operon in Degradation of Galactan by Bacillus subtilis.

Bacillus subtilis possesses different enzymes for the utilization of plant cell wall polysaccharides. This includes a gene cluster containing galactan degradation genes (ganA and ganB), two transporter component genes (ganQ and ganP), and the sugar-binding lipoprotein-encoding gene ganS (previously known as cycB). These genes form an operon that is regulated by GanR.

Construction of a Super-Competent Bacillus subtilis 168 Using the P mtlA -comKS Inducible Cassette.

Competence is a physiological state that enables Bacillus subtilis 168 to take up and internalize extracellular DNA. In practice, only a small subpopulation of B. subtilis 168 cells becomes competent when they enter stationary phase.

An Alternative Bacterial Expression System Using SG2 Chitinase Promoter.

Background: Chitin is an abundant natural polysaccharide found in fungi, algae, and exoskeleton of insects. Several bacterial species are capable of utilizing chitin as their carbon source. These bacteria produce chitinases for degradation of chitin into -acetyl-D-glucosamine.

Development of an anhydrotetracycline-inducible expression system for expression of a neopullulanase in B. subtilis.

Bacillus subtilis is a widely used bacterium for production of heterologous and homologous proteins. The primary challenge in the production of proteins in B. subtilis is choosing a relevant expression system.

Transcriptional regulation of the vanillate utilization genes (vanABK Operon) of Corynebacterium glutamicum by VanR, a PadR-like repressor.

Corynebacterium glutamicum is able to utilize vanillate, the product of lignin degradation, as the sole carbon source. The vanillate utilization components are encoded by the vanABK operon. The vanA and vanB genes encode the subunits of vanillate O-demethylase, converting vanillate to protocatechuate, while VanK is the specific vanillate transporter.

Regulation of the Bacillus subtilis mannitol utilization genes: promoter structure and transcriptional activation by the wild-type regulator (MtlR) and its mutants.

Expression of mannitol utilization genes in Bacillus subtilis is directed by PmtlA, the promoter of the mtlAFD operon, and PmtlR, the promoter of the MtlR activator. MtlR contains phosphoenolpyruvate-dependent phosphotransferase system (PTS) regulation domains, called PRDs. The activity of PRD-containing MtlR is mainly regulated by the phosphorylation/dephosphorylation of its PRDII and EIIB(Gat)-like domains.

Regulation of mtl operon promoter of Bacillus subtilis: requirements of its use in expression vectors.

Background: Several vector systems have been developed to express any gene desired to be studied in Bacillus subtilis. Among them, the transcriptionally regulated promoters involved in carbohydrate utilization are a research priority. Expression systems based on Bacillus promoters for xylose, maltose, and mannose utilization, as well as on the heterologous E.

Isolation and identification of a lipase producing Bacillus sp. from soil.

Lipase production in an indigenous lipolytic Bacillus sp. was detected in media containing Tributyrin-Tween 80 and Rhodamine B-Olive oil. The statistical Taguchi model was used to predict the optimum experimental conditions for bacterial growth and lipase production.