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Top: The surfactin biosynthetic gene cluster. Structural NRPS genes are indicated in red. The regulatory gene comS, which is co-encoded in SrfAB is indicated in purple. Bottom: Classic module and domain architecture of SrfAA-SrfAD.
Source publication
Surfactin is a lipoheptapeptide produced by several Bacillus species and identified for the first time in 1969. At first, the biosynthesis of this remarkable biosurfactant was described in this review. The peptide moiety of the surfactin is synthesized using huge multienzymatic proteins called NonRibosomal Peptide Synthetases. This mechanism is res...
Citations
... Amphiphilic properties allow self-assembly and interfacial tension reduction behavior-a feature that confers foaming, emulsification, and drug delivery properties and application Theatre et al. (2021) Surface-acting behavior The net negative charge (due to the presence of Glu and Asp) influences the physicochemical properties of surfactins Liu et al.(2012) and Theatre et al. (2021) Antiviral properties The cyclicity of surfactins confers surface-acting behavior that mediates antiviral behavior (by inhibiting membrane-fusion between virus and host cell) Liu et al. (2012) and Yuan et al. (2018) F I G U R E 2 Chemical structures of (a) iturin, (b) fengycin, (c) surfactin, and (d) polymyxin. ...
... Amphiphilic properties allow self-assembly and interfacial tension reduction behavior-a feature that confers foaming, emulsification, and drug delivery properties and application Theatre et al. (2021) Surface-acting behavior The net negative charge (due to the presence of Glu and Asp) influences the physicochemical properties of surfactins Liu et al.(2012) and Theatre et al. (2021) Antiviral properties The cyclicity of surfactins confers surface-acting behavior that mediates antiviral behavior (by inhibiting membrane-fusion between virus and host cell) Liu et al. (2012) and Yuan et al. (2018) F I G U R E 2 Chemical structures of (a) iturin, (b) fengycin, (c) surfactin, and (d) polymyxin. ...
... Generally, surfactins are cyclic heptapeptides linked to β-hydroxy fatty acid tails (see Figure 2c). Theatre et al. (2021) reported three main structural features responsible for the biological properties of surfactins: (a) the cyclic nature of the compound, (b) the combinations of unique peptides and fatty acids representing the polar and non-polar groups, respectively, and (c) the net charge of the polar group. Collectively, these features afford surfactins the ability to act at interfaces and demonstrate a surface-acting behavior. ...
Lipopeptides are a class of lipid–peptide‐conjugated compounds with differing structural features. This structural diversity is responsible for their diverse range of biological properties, including antimicrobial, antioxidant, and anti‐inflammatory activities. Lipopeptides have been attracting the attention of food scientists due to their potential as food additives and preservatives. This review provides a comprehensive overview of lipopeptides, their production, structural characteristics, and functional properties. First, the classes, chemical features, structure–activity relationships, and sources of lipopeptides are summarized. Then, the gene expression and biosynthesis of lipopeptides in microbial cell factories and strategies to optimize lipopeptide production are discussed. In addition, the main methods of purification and characterization of lipopeptides have been described. Finally, some biological activities of the lipopeptides, especially those relevant to food systems along with their mechanism of action, are critically examined.
... Bacteria of the genus Bacillus are capable of producing several surfactin congeners with fatty acid chains of 12 to 17 carbon atoms in length that could be linear, iso or anteiso branches and varying amino acid sequence [37,71,72]. So far, more than 40 different variants of surfactin have been identified [38]. ...
... with fatty acid chains of 12 to 17 carbon atoms in length that could be linear, iso or anteiso branches and varying amino acid sequence [37,71,72]. So far, more than 40 different variants of surfactin have been identified [38]. ...
In a scenario of increasing alarm about food waste due to rapid urbanization, population growth and lifestyle changes, this study aims to explore the valorization of waste from the retail sector as potential substrates for the biotechnological production of biosurfactants. With a perspective of increasingly contributing to the realization of the circular bioeconomy, a vegetable juice, derived from unsold fruits and vegetables, as a carbon source was used to produce lipopeptides such as surfactin and fengycin. The results from the shake flask cultivations revealed that different concentrations of vegetable juice could effectively serve as carbon sources and that the fed-batch bioreactor cultivation strategy allowed the yields of lipopeptides to be significantly increased. In particular, the product/substrate yield of 0.09 g/g for surfactin and 0.85 mg/g for fengycin was obtained with maximum concentrations of 2.77 g/L and 27.53 mg/L after 16 h, respectively. To conclude, this study provides the successful fed-batch cultivation of B. subtilis using waste product as the carbon source to produce secondary metabolites. Therefore, the consumption of agricultural product wastes might be a promising source for producing valuable metabolites which have promising application potential to be used in several fields of biological controls of fungal diseases.
... Lipopeptide biosurfactants, predominantly produced by organisms such as B. subtilis, Bacillus licheniformis, and Micrococcus luteus, comprise a sequence of amino acids and one to two fatty acids. Surfactin is the most extensively employed among lipopeptides, encoded by the sfp genes and the srfA-A, srfA-B, srfA-C, srfA-C-TE, and srfA-TE genes [67,68]. The sfp and srfA genes are commonly used. ...
Biosurfactants derived from microorganisms have attracted widespread attention in scientific research due to their unique surface activity, low toxicity, biodegradability, antibacterial properties, and stability under extreme conditions. Biosurfactants are widely used in many fields, such as medicine, agriculture, and environmental protection. Therefore, this review aims to comprehensively review and analyze the various applications of biosurfactants in the medical field. The central roles of biosurfactants in crucial medical areas are explored, like drug delivery, induction of tumor cell differentiation or death, treating bacterial and viral effects, healing wounds, and immune regulation. Moreover, a new outlook is introduced on optimizing the capabilities of biosurfactants through modification and gene recombination for better use in medicine. The current research challenges and future research directions are described, aiming to provide valuable insights for continuous study of biosurfactants in medicine.
... SrfAA and srfAB are responsible for three amino acid assemblies (Leu, Glu, Val and Asp, Val, Leu), respectively, srfAC is responsible for the seventh amino acid assembly (Leu) and coding the rst TE domain in order to terminate elongation of the peptide chain and peptide release, and srfAD encodes second TE domain to activate peptide cyclization [56]. ComA is also a key factor for regulating surfactin biosynthesis, which is regulated by ComQXP, RapC, SodA and DegQ [57]. Surfactin-producing genes including srfAA, srfAB, srfAC and srfAD were signi cantly downregulated in BSS, indicating that the key step of surfactin synthesis, the peptide chain extension, was signi cantly inhibited, thereby resulting in a drastically decreased surfactin yield. ...
Background
The outer space is an extreme environment that has attracted continuous interest in microbial adaptation and safety, due to its high mutagenesis frequency and genetic variability. To date, several studies have assessed the impact of the space environment on the microbiomes and microorganisms. While the survival of Bacillus subtilis after spaceflight is well established, how the phenotype and metabolic function of B. subtilis respond to space stress is rarely reported.
Results
In this study, we performed a space flight of the B. subtilis TD7 strain facilitated by the launch project of the Xinyidai Zairen Feichuan-Shiyan Chuan, and compared the strains after spaceflight with the wild-type in terms of their growth, morphology, biofilm formation and secondary metabolism. The spaceflight strain exhibited slower growth, higher cell density, different morphology and decreased biofilm formation. Importantly, a decrease in the lipopeptide production was observed after spaceflight. Thus, we used a multi-omics approach to uncover the molecular mechanisms underlying the changeable secondary metabolism. A total of 14 gene clusters for secondary metabolite biosynthesis were identified in both the wild-type strain and spaceflight strains through whole-genome sequencing, including nonribosomal peptide synthetase. The comparative transcriptome revealed 997 differentially expressed genes which involved in the TCA cycle, fatty acid degradation, amino acid biosynthesis, and quorum sensing systems. The differential expression analysis of 26 lipopeptide-related DEGs further elucidated the relationship between the space environment and the regulation of secondary metabolism.
Conclusion
Our study is the first study to provide new insight into the behaviors, metabolic functions and adaptation mechanisms of B. subtilis in response to spaceflight. This knowledge could contribute to a better understanding of the relationship between the space environment and microbial adaption mechanisms.
... Its chemical structure consists of a cycloheptapeptide, which is interlinked with β-hydroxy fatty acid chains of variable length containing 12−17 carbon atoms. Giant biosynthetic gene clusters (BGCs) involved in synthesis of surfactin were detected in many representatives of the Bacillus subtilis species complex, such as B. subtilis, B. atrophaeus, B. spizizenii, B. amyloliquefaciens, and B. velezensis [1,13]. The surfactin BGC (e. g. ...
Surfactin is a cyclic hexalipopeptide compound, nonribosomal synthesized by representatives of the Bacillus subtilis species complex which includes B. subtilis group and its closely related species, such as B. subtilis subsp subtilis, B. subtilis subsp spizizenii, B. subtilis subsp inaquosorum, B. atrophaeus, B. amyloliquefaciens, B. velezensis (Steinke mSystems 6: e00057, 2021) It functions as a biosurfactant and signaling molecule and has antibacterial, antiviral, antitumor, and plant disease resistance properties. The Bacillus lipopeptides play an important role in agriculture, oil recovery, cosmetics, food processing and pharmaceuticals, but the natural yield of surfactin synthesized by Bacillus is low. This paper reviews the regulatory pathways and mechanisms that affect surfactin synthesis and release, highlighting the regulatory genes involved in the transcription of the srfAA-AD operon. The several ways to enhance surfactin production, such as governing expression of the genes involved in synthesis and regulation of surfactin synthesis and transport, removal of competitive pathways, optimization of media, and fermentation conditions were commented. This review will provide a theoretical platform for the systematic genetic modification of high-yielding strains of surfactin.
Graphical Abstract
... The finding indicates that the exogenous addition of amino acids and branched fatty acids did not induce the formation of a novel surfactin structure, but rather modulated the proportion of surfactin homologue components within the product. Previous studies have shown that different homologue compositions affect surfactin activity [28]. Branched-chain surfactin offers superior properties, including high oxidative stability, a low melting point, low viscosity, and improved flexibility, promising significant commercial potential in personal care and industrial processes [29]. ...
Background
Surfactin, a green lipopeptide bio-surfactant, exhibits excellent surface, hemolytic, antibacterial, and emulsifying activities. However, a lack of clear understanding of the synthesis regulation mechanism of surfactin homologue components has hindered the customized production of surfactin products with different biological activities.
Results
In this study, exogenous valine and 2-methylbutyric acid supplementation significantly facilitated the production of C14–C15 surfactin proportions (up to 75% or more), with a positive correlation between the homologue proportion and fortified concentration. Subsequently, the branched-chain amino acid degradation pathway and the glutamate synthesis pathway are identified as critical pathways in regulating C14–C15 surfactin synthesis by transcriptome analysis. Overexpression of genes bkdAB and glnA resulted in a 1.4-fold and 1.3-fold increase in C14 surfactin, respectively. Finally, the C14-rich surfactin was observed to significantly enhance emulsification activity, achieving an EI24 exceeding 60% against hexadecane, while simultaneously reducing hemolytic activity. Conversely, the C15-rich surfactin demonstrated an increase in both hemolytic and antibacterial activities.
Conclusion
This study presents the first evidence of a potential connection between surfactin homologue synthesis and the conversion of glutamate and glutamine, providing a theoretical basis for targeting the synthesis regulation and structure–activity relationships of surfactin and other lipopeptide compounds.
Graphical Abstract
... Especies de Bacillus producen metabolitos secundarios, como lipopéptidos con potencial importante como inhibidores de fitopatógenos (Ongena et al., 2008;Théatre et al., 2021). ...
Se analizaron muestras de suelo y raíces del cultivo del pepino. Se extrajeron e identificaron los nematodos fitopatógenos presentes. Juveniles de Meloidogyne incognita fueron los más abundantes en suelo, otros como Aphelenchoides sp., Pratylenchus sp., Tylenchorynchus sp., y Aphelenchus sp. se encontraron con menor presencia. De las raíces se obtuvieron hembras y huevos de M. incognita. Con el fin de encontrar alternativas a los productos químicos fumigantes utilizados en exceso, se evaluaron las rizobacterias Bacillus vallismortis, Bacillus velezensis y Pseudomonas fluorescens, que fueron fermentadas y filtradas para ponerse en contacto con estos nematodos bajo condiciones in vitro, observando su efecto cada 24 h. Los tratamientos se analizaron en concentraciones de 100% y 50%. El filtrado de P. fluorescens presentó la mejor actividad nematicida, ocasionando una mortalidad de 95% en la concentración más alta y de 93 % en la concentración de 50 % a las 24 h, seguido por los tratamientos de B. vallismortis y B. velezensis con 83 y 77 % de respectivamente, en las concentraciones más altas. Los tres tratamientos ocasionaron un 100 % de mortalidad de los nematodos a 48 h de exposición, indicando, que contienen acción nematicida y pueden ser una alternativa viable para el control de estos fitopatógenos.
... Other peptide variants of the surfactin family, named lichenysin and pumilacidin, have been isolated from B. licheniformis and B. pumilis, respectively [15,16] . Lipopeptides belonging to surfactin family are the most powerful biosurfactants with interesting functional properties [17] , known for their high emulsifying [18,19] , detergent [20] and foaming capacities [21,19] . Surfactins have also shown several pharmacological activities, such as antimicrobial, antiviral [22,23] , anti-tumor [24] , anti-inflammatory [25,26] , antifibrinolytic and hypocholesterolemic [27] activities. ...
Lipopeptide biosurfactants are produced by a variety of microorganisms, those synthesized by Bacillus spp. are the most widely studied. Due to their amphiphilic nature and various structures, lipopeptides present different functional properties such as emulsifying, detergent, dispersing, wetting and foaming effects. They exhibit multiple biological activities including antimicrobial, antiviral, anti-biofilm, antitumor and immunomodulatory activities. Given their potentiality and safety, lipopeptides are used today in different fields of application such as the bioremediation of environments contaminated with hydrocarbons and the petroleum industries, cosmetics, medicine and the pharmaceutical field, agriculture and food industries.
... However, we differentiate four isomers namely Surfactin, Lichenysin, Esperin and Pumilacidin among the Surfactin family that vary on the seventh amino acid (Mnif & Ghribi 2015a;Ali et al. 2022). Additionally, linear non-ester-cyclized isoforms were largely identified as described here and numerous previous work (Wang et al. 2004;Pathak et al. 2014;Ma et al. 2016;Théatre et al. 2021). ...
The purification and characterization of lipopeptides biosurfactants produced by Bacillus sp. MI27 permits to identify two clusters of cyclic and linear surfactin isoforms. Aiming for a potential application in industrial biotechnology, we studied its potential washing capacity. The results show a good ability to wash oil stains, motor oil and mayonnaise evaluated by the determination of the % of stain removal and tissue bleaching indices after washing. Optimal washing capacities were unregistered for 300 and 400 mg/L at pH values ranging from 5 to 9 and temperatures ranging from 20 to 40°C. Using a 4-factor mixing design, we optimized a liquid formula composed only of BioS; silicate; carboxymethyl cellulose and calcium phosphate. The washing efficiency of the formula is of the order of 43.46% for petroleum and 49.10% for motor oil with a percentage reduction in surface tension of about 55.79% corresponding to 25.7 mN/m.
... Lipopeptides are linear or cyclic peptides each linked to a hydrophobic carbon tail that confers amphiphilic properties, and therefore a biosurfactant activity. Among this family, surfactins are well characterized as heptapeptides with an LLDLLDL chiral sequence linked, via a lactone bond, to a beta-hydroxy fatty acid with 13-15 C atoms [12,13]. Their surfactant properties confer to them antibacterial activities through bacterial membrane disruption [14]. ...
... The srfA operon is composed of four open reading frames encoding four enzymatic modules of surfactin synthetase. The surfactin synthetase catalyzes the synthesis of the surfactin peptidic chain by a non-ribosomal peptide synthetase (NRPS) process [13]. Surfactin has a dual role as a probiofilm for the producer and antibiofilm for other bacteria. ...
V. harveyi is a well-known pathogen-inducing vibriosis, especially for shrimp, fish, and invertebrates. Its virulence is related to biofilm formation and this negatively impacts the aquaculture industry. Therapeutic strategies such as the utilization of probiotic bacteria may slow down Vibrio infections. In this study, we investigated the potential antibiofilm activity of the probiotic Bacillus subtilis C3 for aquaculture. First, B. subtilis C3 biofilm was characterized by confocal laser scanning microscopy (CLSM) before testing its bioactivities. We demonstrated antibiofilm activity of B. subtilis C3 culture supernatant, which is mainly composed—among other molecules—of lipopeptidic surfactants belonging to the surfactin family as identified by ultra-high-performance liquid chromatography (UHPLC)-MS/MS. Their antibiofilm activity was confirmed on V. harveyi ORM4 (pFD086) biofilm by CLSM. These findings suggest that the marine probiotic B. subtilis C3 might inhibit or reduce Vibrio colonization and thus decrease the associated animal mortalities.
