Lactic Acid Bacteria Leuconostoc Mesenteroides Research Articles

Monitoring the Season-Prevalence Relationship of Vairimorpha ceranae in Honey Bees (Apis mellifera) over One Year and the Primary Assessment of Probiotic Treatment in Taichung, Taiwan.

Microsporidiosis, which is caused by the pathogen Vairimorpha ceranae, is a prevalent disease in the honey bee (Apis mellifera) and might lead to significant adult honey bee mortality. In this study, we conducted an annual survey of the mature spore load of V. ceranae in the guts of nurse bees and forager bees in the apiary of National Chung Hsing University (NCHU) in Taiwan. The results indicated that, on average, honey bees hosted approximately 2.13 × 106 mature spore counts (MSCs)/bee in their guts throughout the entire year. The highest number of MSCs was 6.28 × 106 MSCs/bee, which occurred in April 2020, and the lowest number of MSCs was 5.08 × 105 MSCs/bee, which occurred in November 2020. Furthermore, the guts of forager bees had significantly higher (>58%) MSCs than those of nurse bees. To evaluate the potential of the probiotic to treat microsporidiosis, the lactic acid bacterium Leuconostoc mesenteroides TBE-8 was applied to honey bee colonies. A significant reduction (>53%) in MSCs following probiotic treatment was observed, indicating the potential of probiotic treatment for managing microsporidiosis. This research provided information on V. ceranae MSCs in the honey bee gut at NCHU in Taiwan and the MSCs' correlation with the annual season. Furthermore, a potential probiotic treatment for microsporidiosis was assessed for future management.

Carotenoid productivity in human intestinal bacteria Eubacterium limosum and Leuconostoc mesenteroides with functional analysis of their carotenoid biosynthesis genes

The human intestinal microbiota that comprise over 1,000 species thrive in dark and anaerobic environments. They are recognized for the production of diverse low-molecular-weight metabolites crucial to human health and diseases. Carotenoids, low-molecular-weight pigments known for their antioxidative activity, are delivered to humans through oral intake. However, it remains unclear whether human intestinal bacteria biosynthesize carotenoids as part of the in-situ microbiota. In this study, we investigated carotenoid synthesis genes in various human gut and probiotic bacteria. As a result, novel candidates, the crtM and crtN genes, were identified in the carbon monoxide-utilizing gut anaerobe Eubacterium limosum and the lactic acid bacterium Leuconostoc mesenteroides subsp. mesenteroides. These gene candidates were isolated, introduced into Escherichia coli, which synthesized a carotenoid substrate, and cultured aerobically. Structural analysis of the resulting carotenoids revealed that the crtM and crtN gene candidates of E. limosum and L. mesenteroides mediate the production of 4,4′-diaponeurosporene through 15-cis-4,4′-diapophytoene. Evaluation of the crtE-homologous genes in these bacteria indicated their non-functionality for C40-carotenoid production. E. limosum and L. mesenteroides, along with the known carotenogenic lactic acid bacterium Lactiplantibacillus plantarum, were observed to produce no carotenoids under strictly anaerobic conditions. The two lactic acid bacteria synthesized detectable levels of 4,4′-diaponeurosporene under semi-aerobic conditions. The findings highlight that the obligate anaerobe E. limosum retains aerobically functional C30-carotenoid biosynthesis genes, potentially with no immediate self-utility, suggesting an evolutionary direction in carotenoid biosynthesis. (229 words)

RESEARCH OF HARD CHEESE RIPENING REGIMES AS A FUNCTION OF THE COMPOSITION OF BACTERIAL STARTER CULTURES

The ripening of cheese, caused by the combined effect of the fermentative enzyme and microflora of the bacterial starter, occurs in certain intervals of temperature, humidity and acidity of the environment which depend on the type of cheese. The composition of bacterial starters for hard cheese is important for formation of the finished product properties and affects the choice of technological regimes. Even minor changes in ripening conditions can significantly affect the microbiological, physicochemical, biochemical parameters, organoleptic properties, and safety of the target product. The aim of the investigation was to study the influence of ripening temperature regimes on the physicochemical, biochemical and organoleptic characteristics of hard cheeses with a low temperature of the second heating aged 30 days, produced using different compositions of bacterial starters. It was shown that the inclusion of lactobacilli Lactobacillus casei in the composition of the bacterial starter "Active" makes it possible to intensify proteolysis, and the using of aroma-forming lactic acid bacteria Leuconostoc mesenteroides in the starter culture "Active-LN" has a positive effect on the formation of the taste-aromatic composition and texture of the cheese. Changes in the microbiological parameters of cheeses at different stages of production were monitored and the sanitary and hygienic properties of the finished products were evaluated. It was established that cheeses produced both with the use of starter cultures "Active" and "Active-LN" had been ripened best at a temperature of 12–13°C. The products had a good taste and aroma with distinctive features of each type of cheese microbiota, a plastic consistency and a pattern with correctly shaped eyes, larger in cheese with "Aktiv-LN". Thus, the temperature 12–13°С and humidity 75–85% are adequate for the ripening of these cheeses and ensure the formation of a specific taste and aromatic composition of the products and the required level of maturation during 30 days.

Dextran sulfate from Leuconostoc mesenteroides B512F exerts potent antiviral activity against SARS-CoV-2 in vitro and in vivo.

The emergent human coronavirus SARS-CoV-2 and its resistance to current drugs makes the need for new potent treatments for COVID-19 patients strongly necessary. Dextran sulfate (DS) polysaccharides have long demonstrated antiviral activity against different enveloped viruses in vitro. However, their poor bioavailability has led to their abandonment as antiviral candidates. Here, we report for the first time the broad-spectrum antiviral activity of a DS-based extrapolymeric substance produced by the lactic acid bacterium Leuconostoc mesenteroides B512F. Time of addition assays with SARS-CoV-2 pseudoviruses in in vitro models confirm the inhibitory activity of DSs in the early stages of viral infection (viral entry). In addition, this exopolysaccharide substance also reports broad-spectrum antiviral activity against several enveloped viruses such as SARS-CoV-2, HCoV229E, HSV-1, in in vitro models and in human lung tissue. The toxicity and antiviral capacity of DS from L. mesenteroides was tested in vivo in mouse models which are susceptible to SARS-CoV-2 infection. The described DS, administered by inhalation, a new route of administration for these types of polymers, shows strong inhibition of SARS-CoV-2 infection in vivo, significantly reducing animal mortality and morbidity at non-toxic doses. Therefore, we suggest that it may be considered as a potential candidate for antiviral therapy against SARS-CoV-2.

Coinoculation of lactic acid bacteria and yeasts increases the quality of wet fermented Arabica coffee

Wet coffee fermentation is widely used in coffee-producing regions such as Colombia and Hawaii, but it is not widespread in Brazil. This study aimed to evaluate inoculating the lactic acid bacteria Leuconostoc mesenteroides CCMA1105 and Lactiplantibacillus plantarum CCMA 1065 and the yeasts Saccharomyces cerevisiae CCMA0543 and Torulaspora delbrueckii CCMA0684 as starter cultures on wet coffee fermentation using the SIAF method (self-induced anaerobiosis fermentation). The microbial activity resulted in high consumption of the carbohydrates glucose (98.6%), fructose (97.6%), and sucrose (100%), in addition to the production of lactic and acetic acids, impacting the final quality of the beverage. A total of 108 volatile compounds belonging to 17 classes were identified in the green and roasted coffee samples, including 2,3-butanediol produced by lactic acid bacteria, contributing to coffee's aromatic profile. The final scores for the coffees from the different fermentations ranged from 79.0 to 83.25. The inoculated fermentations were classified as specialty according to the Specialty Coffee Association. Therefore, whole coffee fruit processed via wet using SIAF method and yeast and lactic acid bacteria starter is an alternative for improving wet fermented coffee quality and obtaining coffee beverages with a different sensory profile.

Dextran-Based Edible Coatings to Prolong the Shelf Life of Blueberries.

The development of edible films and coatings in the food packaging industry presents one of the modern strategies for protecting food products and ensuring their freshness and quality during their shelf lives. The application of microbial polysaccharides to the development of food package materials, as an alternative option to the commonly used plastic materials, is both economic and environmentally favorable. New edible films were developed using dextran from lactic acid bacterium Leuconostoc mesenteroides T3, and additionally plasticized by different concentrations of polyglycerol. The best tensile strength of the films was obtained using a formulation that contained 10 wt% of polyglycerol, which corresponded to a value of 4.6 MPa. The most flexible formulation, with elongation at break of 602%, was obtained with 30 wt% of polyglycerol. Water vapor permeability values of the films synthesized in this study were in the range of (3.45–8.81) ∗ 10−12 g/m s Pa. Such low values indicated that they could be efficient in preventing fruit from drying out during storage. Thus, the film formulations were used to coat blueberries in order to assess their quality during a storage time of 21 days at 8 °C. The results showed that dextran/polyglycerol films could be efficient in extending the shelf life of blueberries, which was evidenced by lower weight loss and total sugar solids values, as well as a delay in titratable acidity, in comparison to the uncoated blueberries.

The crucial role of yeasts in the wet fermentation of coffee beans and quality

The objective of this study was to investigate the role of yeasts in the wet fermentation of coffee beans and their contribution to coffee quality using a novel approach. Natamycin (300 ppm) was added to the fermentation mass to suppress yeast growth and their metabolic activities, and the resultant microbial ecology, bean chemistry and sensory quality were analyzed and compared to non-treated spontaneous fermentation we reported previously. The yeast community was dominated by Hanseniaspora uvarum and Pichia kudriavzevii and grew to a maximum population of about 5.5 log CFU/g in the absence of Natamycin, while when Natamycin was added yeasts were suppressed. The major bacterial species in both the spontaneous and yeast-suppressed fermentations included the lactic acid bacteria Leuconostoc mesenteroides and Lactococcus lactis, the acetic acid bacteria Gluconobacter cerinus and Acetobacter persici and the Enterobacteriaceae Enterobacter, Citrobacter and Erwinia. For both fermentations, the mucilage layers were completely degraded by the end of the process and the absence of yeast activities had no significant impact on mucilage degradation. During fermentation, reducing sugars were consumed while lactic acid was accumulated inside the beans, and its concentration was significantly higher in the spontaneous fermentation (3 times) than that where yeasts were suppressed by Natamycin. Glycerol was detected with a concentration of 0.08% in the absence of Natamycin and was not identified when Natamycin was added. Green beans fermented with yeast growth contained a higher amount of isoamyl alcohol (21 times), ethanol (3.7 times), acetaldehyde (8 times), and ethyl acetate (25 times) compared to beans fermented in the absence of yeast activities, which remained higher in the former after roasting. Beans fermented without yeast activities had a mild fruity aroma, and lower sensory scores of fragrances (7.0), flavor (6.5), acidity (6.3), body (7.0) and overall score (6.5) compared to the former. These findings demonstrated the crucial roles of yeasts in wet fermentation of coffee beans and for producing high quality coffee.

Three-dimensional structure modeling of a protease from lactic acid bacteria Leuconostoc mesenteroides K7 using automated protein homology analysis

Abstract. Hidayat H, Haryadi W, Raharjo TJ. 2020. Three-dimensional structure modeling of a protease from lactic acid bacteria Leuconostoc mesenteroides K7 using automated protein homology analysis. Biodiversitas 21: 3156-3162. This study aimed to characterize the protease encoding gene of Leuconostoc mesenteroides K7 isolated from Kelengkeng (Dimocarpus longan) fruit as well as to predict the structure of the protein using in silico approach. Gene characterization was performed using PCR employs primers designed based on protease gene of other Leuconostoc species, followed by cloning and sequencing of the PCR product. Protein structural modeling was targeted to the deduced amino acid sequence of the gene employ multiple sequence alignment and SWISS-Model online software. As a result, the sequence of the PCR product contains an open reading frame with a size of 1,140 bp, which can be translated into 379 amino acids. The amino acid sequence shares 98.60% identity with protease from Leuconostoc suionicum (AP017935.1). Three conserved sequences of QTDA, INPGNSGGPL, and FAIP are known as the signature from the Serine endoprotease DegS family are detected. The three-dimensional modeling structure application shows that the protein share similarity of 37.62% to Protease Do-like I chloroplastic that belong to serine protease.

Synthesis and Physicochemical Properties of Exopolysaccharides Produced by Lactic Acid Bacteria Leuconostoc mesenteroides Cultured in Lactose- and Sucrose-Containing Medium

The dynamics of Leuconostoc mesenteroides bacteria growth and synthesis of exoplysaccharides when cultured on a medium containing whey and sucrose has been investigated. It was shown that exopolysaccharides were produced during the culture growth and the addition of sucrose increased in the productivity of those compounds without affecting their composition. Using the dynamic and static methods of light scattering, it was shown that sucrose as a medium component modified physicochemical properties of exopolysaccharides changing their structural and thermodynamic characteristics in aqueous medium, which affected their functional activity and determined the way of their most efficient use. kefir fungi, lactic acid bacteria, physicochemical properties of exopolysaccharides.

Influence of consortia of lactic acid microorganisms on the dynamics of active and titratable acidity at the main stage of fermentation of white cabbage

Fermented cabbage is traditionally produced naturally, where under the action of lactic acid bacteria contained in raw materials, carbohydrates are converted into lactic acid. However, the direct fermentation process does not always lead to an optimal quality product. That is why the use of lactic acid microorganisms is a good alternative to the direct fermentation of cabbage, as with the help of starter cultures the process can be controlled. In this connection, the use of strains of lactic acid microorganisms allows to achieve rapid production of lactic and acetic acids and leads to a rapid decrease in pH, which in turn leads to the suppression of pathogenic microflora, and therefore to the creation of favorable conditions for the fermentation process. The aim of this study was to study the effect of consortia of lactic acid microorganisms on the dynamics of active and titratable acidity in the main stage of fermentation of white cabbage of the variety "Parus". For the study, the prepared modified model medium (MMC) from cabbage was used. In this work, we used lactic acid bacteria Leuconostoc mesenteroides and its consortia: L. mesenteroides + L. casei, L. mesenteroides + L. plantarum, L. mesenteroides + L. brevis, L. mesenteroides + L. casei + L. plantarum, L. mesenteroides + L. plantarum + L. brevis, L. mesenteroides + L. brevis + L. casei. Mathematical processing was carried out according to the obtained experimental data. Analysis of experimental data showed that at the main stage of fermentation the relationship of lactic acid microorganisms in the studied consortia was expressed by synergistic and antagonistic properties. In this case, the best results on the dynamics of growth of active and titratable acidity were obtained in consortiums L. mesenteroides + L. plantarum, L. mesenteroides + L. casei + L. plantarum, L. mesenteroides + L. plantarum + L. brevis.

High Levels of CO2 Induce Spoilage by Leuconostoc mesenteroides by Upregulating Dextran Synthesis Genes.

During nonventilated storage of carrots, CO2 gradually accumulates to high levels and causes modifications in the carrot's microbiome toward dominance of Lactobacillales and Enterobacteriales The lactic acid bacterium Leuconostoc mesenteroides secretes a slimy exudate over the surface of the carrots. The objective of this study was to characterize the slime components and the potential cause for its secretion under high CO2 levels. A proteomic analysis of the exudate revealed bacterial glucosyltransferases as the main proteins, specifically, dextransucrase. A chemical analysis of the exudate revealed high levels of dextran and several simple sugars. The exudate volume and dextran amount were significantly higher when L. mesenteroides was incubated under high CO2 levels than when incubated in an aerated environment. The treatment of carrot medium plates with commercial dextransucrase or exudate protein extract resulted in similar sugar profiles and dextran production. Transcriptome analysis demonstrated that dextran production is related to the upregulation of the L. mesenteroides dextransucrase-encoding genes dsrD and dsrT during the first 4 to 8 h of exposure to high CO2 levels compared to aerated conditions. A phylogenetic analysis of L. mesenteroides YL48 dsrD revealed a high similarity to other dsr genes harbored by different Leuconostoc species. The ecological benefit of dextran production under elevated CO2 requires further investigation. However, this study implies an overlooked role of CO2 in the physiology and fitness of L. mesenteroides in stored carrots, and perhaps in other food items, during storage under nonventilated conditions.IMPORTANCE The bacterium Leuconostoc mesenteroides is known to cause spoilage of different types of foods by secreting a slimy fluid that damages the quality and appearance of the produce. Here, we identified a potential mechanism by which high levels of CO2 affect the spoilage caused by this bacterium by upregulating dextran synthesis genes. These results have broader implications for the study of the physiology, degradation ability, and potential biotechnological applications of Leuconostoc.

Potential use of lactic acid bacteria Leuconostoc mesenteroides as a probiotic for the removal of Pb(II) toxicity

It has been demonstrated that certain lactic acid bacteria (LAB) can sequester metal ions by binding them to their surfaces. In the present study, lead (Pb)-resistant LAB were isolated from kimchi, a Korean fermented food. A total of 96 different LAB strains were isolated, and 52 strains showed lead resistance. Among them, an LAB strain-96 (L-96) identified as Leuconostoc mesenteroides showed remarkable Pb resistance and removal capacity. The maximum adsorption capacity of this strain calculated using the Langmuir isotherm was 60.6 mg Pb/g. In an in vivo experiment, young male mice were provided with water (A), Pb-water (B), or Pb-water+ L-96 (C) during puberty. Lower glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) levels in Pb-exposed male mice that received strain L-96 as a probiotic were suggestive of reduced hepatotoxicity. Moreover, feces from mice treated with L-96 contained more Pb than feces from untreated mice. Increased Pb elimination likely reduced internal accumulation, and this hypothesis was supported by significantly lower Pb concentrations in kidneys and testes of the mice treated with strain L-96. The motility and ATP content of epididymal spermatozoa were partially restored if strain L-96 was administered. In conclusion, isolated L-96 LAB had lead-biosorption activity and efficiently detoxified lead-poisoned male mice, resulting in recovering male reproductive function. These results suggest the potential use of LAB as a probiotic to protect humans from the adverse effects of Pb exposure.

Characterization and Antibacterial Mode of Action of Lactic Acid BacteriumLeuconostoc mesenteroidesHJ69 from Kimchi

This study characterized a lactic acid bacterium Leuconostoc mesenteroides HJ69 at biochemical and molecular level, isolate from traditional Korean fermented food Kimchi. Cell free supernatant (CFS) of L. mesenteroides HJ69 exhibited significant (P < 0.05) antibacterial effect as diameters of inhibition zones (14.34 ± 0.31 – 18.21 ± 0.23 mm) against the tested foodborne pathogenic bacteria with minimum inhibitory concentration and minimum bactericidal concentration values found in the range of 250–2,000 and 500–2,000 μg/mL, respectively. Further, CFS of L. mesenteroides HJ69 revealed its mode of action on membrane integrity as confirmed by the increased release of potassium ions (800 and 750 mM/L), loss of 260-nm absorbing materials (3.85 and 3.77 OD), and increase in relative electrical conductivity (8.6 and 8.2%) against two selected bacteria L. monocytogenes KCTC-3569 (Gram-positive) and Escherichia coli O157:H7 (Gram-negative), respectively. The above findings hypothesize that L. mesenteroides HJ69 compromised its mode of action on membrane integrity, suggesting its enormous potential in the food industry. Practical Applications Asian countries have enormous use of fermented food products enriched with large populations of health-beneficial lactic acid bacteria (LAB). This study describes the isolation of a LAB strain Leuconostoc mesenteroides HJ69 from traditional Korean fermented food Kimchi along with its biochemical and molecular characterization. The cell free supernatant of L. mesenteroides HJ69 displayed remarkable antibacterial effect against various foodborne pathogenic bacteria with a hypothesized mode of action in several assays. These findings suggest that L. mesenteroides HJ69 could be an effective candidate for its practical application in food industry to control the proliferation of foodborne pathogenic bacteria as a natural antimicrobial agent.

Evaluation of Two Lactic Acid Bacteria Starter Cultures for the Fermentation of Natural Black Table Olives (Olea europaea L cv Kalamon)

The production of Greek-style natural black table olives remains an empirical process relying on spontaneous fermentation despite its economic significance. For this reason producers often resort to increased NaCl concentration of the brine to secure quality of the product. In this study we employ two lactic acid bacteria Leuconostoc mesenteroides subsp. mesenteroides Lm139 and Lactobacillus pentosus DSM 16366 as starters in separate laboratory low salinity fermentations of "Kalamon" cultivar olives, processed according to the Greek-style method. L. mesenteroides subsp. mesenteroides Lm139 was previously isolated from Kalamon olives laboratory spontaneous fermentations, while L. pentosus DSM 16366 was isolated from fermenting green olives prepared according to the Spanish-style method. Spontaneous olives fermentation was also performed as a control. Microbiological and physicochemical analyses of the brines revealed that the use of the starters had a significant effect on the olives fermentation, leading to a faster acidification due to the more efficient consumption of soluble sugars in the brines. The final pH value reached by each starter culture used indicates a successful lactic fermentation. The production of lactic acid by the starters and the concomitant drop of the pH value proved to inhibit enterobacteria in a shorter period of time compared to the spontaneous fermentation. Concluding, the use of either of the two lactic acid bacteria as starters in Greek-style Kalamon olives fermentation could lead to a more controllable fermentation at lower salinities. The resulting product could be of higher quality with extended shelf-life while being at the same time safer for the consumer.

The potential of dextran-based glycoconjugates for development of Helicobacter pylori vaccine

We have recently demonstrated that synthetic glycoconjugates based on delipidated lipopolysaccharide (LPS) of Helicobacter pylori and containing an α(1-6)-glucan chain induced broadly cross-reactive functional antibodies in immunized animals. To investigate the candidacy of α(1-6)-glucan as an alternative vaccine strategy we prepared glycoconjugates based on dextrans produced by lactic acid bacteria Leuconostoc mesenteroides B512F and consisting of linear α(1-6)-glucan chains with limited branching. Three dextrans with averaged molecular masses of 5,000 Da, 3,500 Da and 1,500 Da, respectively, were modified with a diamino group-containing linker and conjugated to a carrier protein, tetanus toxoid (TT) or diphtheria toxoid (DT), and their immunological properties investigated. The conjugates were immunogenic in both rabbits and mice and induced specific IgG responses against α(1-6)-glucan-expressing H. pylori LPS. Studies performed with post-immune sera of mice and rabbits immunized with dextran-based conjugates demonstrated cross-reactivity with LPS from typeable and non-typeable strains of H. pylori and selected mutants. The post-immune sera from rabbits that received the conjugates exhibited functional activity against α(1-6)-glucan-positive strains of H. pylori. These data provide evidence that dextran-based conjugates may offer a simplified approach to the development of carbohydrate-based vaccines against H. pylori.

Microbiology and Nutritional Value of Selroti, an Ethnic Fermented Cereal Food of the Himalayas

Selroti is an ethnic fermented rice food of the Himalayas. A total of 125 samples of selroti batters were collected from different villages and markets of the Himalayas. The microbial population of selroti batters showed that lactic acid bacteria (LAB) were present in viable numbers above 108 cfu/g, followed by yeasts at 105 cfu/g. LAB Leuconostoc mesenteroides, Enterococcus faecium, Pediococcus pentosaceus and Lactobacillus curvatus and yeasts Saccharomyces cerevisiae, Saccharomyces kluyveri, Debaryomyces hansenii, Pichia burtonii, and Zygosaccharomyces rouxii were identified. The most prevalent LAB and yeasts in selroti batters were Leuc. mesenteroids (42.9%) and S. cerevisiae (35.6%). Molds and pathogenic bacteria were not detected. It was observed that seasons affect the development and prevalence of microorganisms in the fermented batters. LAB and yeast strains were screened for their acidifying and coagulating capacity, and it was found that most of the LAB strains acidified with lowering of pH up to 4.3. These strains showed a wide spectrum of enzymatic profiles in commercial API-zym kits. All strains of LAB showed antimicrobial activities under the applied condition. The nutritional value of fermented batters was found to be increased. This is the first report on selroti concerning its microbiology and nutritional value.

The microbiology of mixed salad containing raw and cooked ingredients without dressing

Growth of aerobic mesophilic bacteria in mixed salad without dressing, containing cooked sweet corn and raw endive, was similar to that of raw endive alone. At 9°C, sweet corn permitted the growth of the lactic acid bacterium Leuconostoc mesenteroides, whenever the bacterium was present on raw endive, whereas no growth of lactic acid bacteria was recorded on raw endive alone. Listeria monocytogenes, artificially inoculated in the samples, grew more in the mixed salad than in the raw endive alone, for products stored at 6°C and 9°C. Acidification of sweet corn to pH 5.0 was proposed to reduce the development of L. monocytogenes in the mixed salad to a level similar to that recorded in the raw endive alone. Acidification with citric acid reduced spoilage of sweet corn, whereas acetic acid caused necrosis on the leaves of raw endive.

The putative immunity protein of the gram-positive bacteria Leuconostoc mesenteroides is preferentially located in the cytoplasm compartment.

Immunity proteins are though to protect bacteriocin-producing bacterial strains against the bactericidal effects of their own bacteriocin. The immunity protein which protects the lactic acid bacterium Leuconostoc mesenteroides against mesentericin Y105(37) bacteriocin was detected and localized by immunofluorescence and electron microscopy, using antibodies directed against the C-terminal end of the predicted immunity protein. The antibodies recognized the immunity proteins of various strains of Leuconostoc, including Leuconostoc mesenteroides and Leuconostoc gelidum. This study demonstrated that immunity proteins produced by Leuconostoc mesenteroides accumulated in the cytoplasmic compartment of the bacteria. This is in contrast with other known immunity proteins, such as the colicin immunity proteins, which are integral membrane proteins possessing three to four transmembrane domains.

The putative immunity protein of the Gram-positive bacteria Leuconostoc mesenteroides is preferentially located in the cytoplasm compartment

Immunity proteins are thought to protect bacteriocin-producing bacterial strains against the bactericidal effects of their own bacteriocin. The immunity protein which protects the lactic acid bacterium Leuconostoc mesenteroides against mesentericin Y105 37 bacteriocin was detected and localized by immunofluorescence and electron microscopy, using antibodies directed against the C-terminal end of the predicted immunity protein. The antibodies recognized the immunity proteins of various strains of Leuconostoc, including Leuconostoc mesenteroides and Leuconostoc gelidum. This study demonstrated that immunity proteins produced by Leuconostoc mesenteroides accumulated in the cytoplasmic compartment of the bacteria. This is in contrast with other known immunity proteins, such as the colicin immunity proteins, which are integral membrane proteins possessing three to four transmembrane domains.