Lactosmart: A Novel Therapeutic Molecule for Antimicrobial Defense

The problem of antibiotic resistance has prompted researchers around the globe to search for new antimicrobial agents. Antimicrobial proteins and peptides are naturally secreted by almost all the living organisms to fight infections and can be safer alternatives to chemical antibiotics. Lactoferrin (LF) is a known antimicrobial protein present in all body secretions. In this study, LF was digested by trypsin, and the resulting hydrolysates were studied with respect to their antimicrobial properties. Among the hydrolysates, a 21-kDa basic fragment of LF (termed lactosmart) showed promise as a new potent antimicrobial agent. The antimicrobial studies were performed on various microorganisms including Shigella flexneri, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli as well as fungal pathogens such as Candida albicans, Candida tropicalis, and Candida glabrata. In addition, the lipopolysaccharide (LPS)-binding properties of lactosmart were studied using surface plasmon resonance technique in vitro, along with docking of LPS and molecular dynamics (MD) simulation studies. The results showed that lactosmart had better inhibitory effects against pathogenic microorganisms compared to LF. The results of docking and MD simulation studies further validated the tighter binding of LPS to lactosmart compared to LF. The two LPS-binding sites have been characterized structurally in detail. Through these studies, it has been demonstrated that in native LF, only one LPS-binding site remains exposed due to its location being on the surface of the molecule. However, due to the generation of the lactosmart molecule, the second LPS-binding site gets exposed too. Since LPS is an essential and conserved part of the bacterial cell wall, the pro-inflammatory response in the human body caused by LPS can be targeted using the newly identified lactosmart. These findings highlight the immense potential of lactosmart in comparison to native LF in antimicrobial defense. We propose that lactosmart can be further developed as an antibacterial, antifungal, and antibiofilm agent

Serum Cytokine Levels As Critical Parameters in Early Diagnosis of Disease Progression in COVID-19: A Pilot Study

Abstract Background: The severity of Coronavirus disease 2019 (COVID-19) has been proposed to be associated with cytokine dysregulation. A significant number of patients become serious and need intensive care in hospitals. Methods: The concentrations of cytokines interleukin (IL-6, IL-10) and tumor necrosis factor (TNF) were estimated using enzyme-linked immunosorbent assay (ELISA) in serum samples of 60 adult patients infected with SARS-CoV-2 along with 50 healthy controls of the same age. The mean age of the subjects was 50-52 years and included an equal number of males and females. The patients were further grouped as severe (38 patients) and non-severe cases (22 patients). Results: The mean serum cytokine levels were significantly higher in the COVID-19 patients than in the healthy controls. IL-6 was excessively elevated in comparison to IL-10 and TNF. Comparative analysis of severe versus non-severe cases revealed only slight alterations in the cytokine levels: IL-6 being the most elevated in severe cases. The concentration of the liver enzyme ALT was higher than AST in both severe and non-severe cases. The mean concentration of serum electrolytes (Na, K, and Ca) did not vary much between the patients and healthy controls. Conclusion: There was a significant positive correlation between the levels of cytokines serum biomarkers in COVID-19 patients. It may be suggested that early detection of cytokines, especially IL-6 and serum biomarkers can help predict disease prognosis and severity in COVID-19 patients

<span style="font-size:14.0pt;line-height: 115%;font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman"; color:black;mso-ansi-language:EN-IN;mso-fareast-language:EN-IN;mso-bidi-language: HI" lang="EN-IN">Effect of phosphocreatine on H⁺ extrusion, <i>p</i>H_i<i> </i>and dimorphism in <i>Candida albicans</i></span>

785-790<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">Candida albicans <span style="font-size:14.0pt; line-height:115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">is an opportunistic pathogen. Its proliferation in human hosts is believed to be controlled by immunologic mechanisms. The plasma membrane of the fungus posseses an H+-ATPase (PM-ATPase) which actively extrudes protons to generate an electrochemical gradient which is used in co-transport of nutrients. This ATPase is associated with the growth, dimorphism and pathogenicity of the fungus. The physiological concentration of phosphocreatine (PCr) is 20-35 mM in skeletal muscles. H+-extrusion in Candida cells was strongly inhibited by PCr; 44% at 20mM and 69% at 40mM. H+extrusion was stimulated 6.2-fold in the presence of 10mM glucose. This glucose stimulated extrusion was inhibited significantly by PCr; 36% at 20mM and 53% at 40mM. The intracellular pH pattern of cells destined to differentiate was greatly altered in the presence of PCr. Evagination time for control cells was between 90-120 min. PCr, delayed dimorphism, reduced the population of cells differentiating to hyphae and also reduced the length of hyphae after each time interval. Only 60% differentiation was observed with 10mM  PCr and 40% for higher PCr concentration even after 210 min. Direct interaction of PM-ATPase and PCr has been demonstrated by difference spectrum measurement employing stopped flow spectrophotometer. It can be concluded that PCr may be playing a significant role in checking growth and pathogenesis of C. albicans.</span

Disseny i implementació del lloc web www.stignasi-lleida.org seguint el model MPEu+a

Aquest projecte explica pas a pas tot el procés de creació del lloc web de la parròquia Sant Ignasi de Loiola de Lleida, mitjançant criteris d'usabilitat i accessibilitat i així fer possible un web pensada sobretot per a tots els tipus d'usuaris de la parròquia i totes les seves necessitats

Nutrient associated changes in plasma membrane H⁺-ATPase activity of permeabilized <i>Candida albicans </i>cells

241-244Nutrient stimulated H+ extrusion by cells and spheroplasts of Candida albicans and its underlying mechanism has been investigated. Glucose and glutamic acid stimulated extrusion by a factor of 6 and 1.4 respectively in cells, but had no effect on spheroplasts. Proline showed no H+ stimulation in cells, however, it stimulated spheroplasts 1.5 fold. ATPase activity of toluene-ethanoi-Triton-X-100 (TET) permeabilized cells decreased by 20% following exposure to glucose and proline and 30% following exposure to glutamic acid. Permeabilized spheroplasts of Candida albicans showed drastic reduction in ATPase activity by 40%, 70% and 85% following exposure to glucose, proline and glutamic acid respectively. Externally added F-actin fully restored activity in the case of permeabilized cells and partly with spheroplasts suggesting that ATPase interacts with other membrane proteins during nutrient stimulation of cells

Development of Cost-Effective, Ecofriendly Selenium Nanoparticle-Functionalized Cotton Fabric for Antimicrobial and Antibiofilm Activity

In the present study, selenium nanoparticles were synthesized in situ on alkali-activated cotton fabric using guava leaf extract as a reducing agent. The synthesis was monitored by a change in color of fabric from white to light brick red. The UV-DRS analysis confirms the coating of Se NPs on cotton. The XRD, FT-IR, and SEM-EDX characterization techniques were used to analyze the nanoparticles on cotton fabric. The peak at 788 cm−1 in FT-IR confirms the formation of Se NPs on cotton fabric. The XRD analysis confirms that the average crystallite size of as-prepared nanoparticle is ~17 nm. SEM-EDX analysis shows the successful coating of Se NPs on coated fabric. ICP-OES studies confirm 3.65 mg/g of selenium nanoparticles were present on the fabric. The Se-coated-30 showed a larger zone of inhibition against Gram-positive S. aureus (32 mm) compared to Gram-negative strains of E. coli (16 mm) and K. pneumoniae (26 mm). The fabric was also tested against the fungi C. glabrata (45 mm), C. tropicalis (35 mm), and C. albicans (35 mm) and results indicate it is more effective against fungal compared to bacterial strains. The coated fabric inhibits biofilm formation of C. albicans (99%), S. aureus (78%), and E. coli (58%). The results demonstrated excellent antibacterial, antifungal, and antibiofilm activities of the Se-coated-30. The prepared fabric has the potential to be used in medicinal applications and is both ecofriendly and cost effective

Synergistic Interactions of Eugenol-tosylate and Its Congeners with Fluconazole against Candida albicans.

We previously reported the antifungal properties of a monoterpene phenol "Eugenol" against different Candida strains and have observed that the addition of methyl group to eugenol drastically increased its antimicrobial potency. Based on the results and the importance of medicinal synthetic chemistry, we synthesized eugenol-tosylate and its congeners (E1-E6) and tested their antifungal activity against different clinical fluconazole (FLC)- susceptible and FLC- resistant C. albicans isolates alone and in combination with FLC by determining fractional inhibitory concentration indices (FICIs) and isobolograms calculated from microdilution assays. Minimum inhibitory concentration (MIC) results confirmed that all the tested C. albicans strains were variably susceptible to the semi-synthetic derivatives E1-E6, with MIC values ranging from 1-62 μg/ml. The test compounds in combination with FLC exhibited either synergy (36%), additive (41%) or indifferent (23%) interactions, however, no antagonistic interactions were observed. The MICs of FLC decreased 2-9 fold when used in combination with the test compounds. Like their precursor eugenol, all the derivatives showed significant impairment of ergosterol biosynthesis in all C. albicans strains coupled with down regulation of the important ergosterol biosynthesis pathway gene-ERG11. The results were further validated by docking studies, which revealed that the inhibitors snugly fitting the active site of the target enzyme, mimicking fluconazole, may well explain their excellent inhibitory activity. Our results suggest that these compounds have a great potential as antifungals, which can be used as chemosensitizing agents with the known antifungal drugs

Effect of nitric oxide on H⁺-efflux in presence of various nutrients in <i>Candida albicans</i>

86-90In the present study tentative link has been established between H+-efflux and effect of NO in presence of various nutrients (glucose, 2-deoxy-D-glucose, xylose, proline, glutamic acid and lysine) in C. albicans using sodium nitroprusside (SP) as a potent source of NO. It was observed that there was a decreasing trend in pH with time, in control, while SNP treated cells showed an initial decline in pH for 10-15 min, followed by an increase in pH up to 30 min. In presence of glucose there was an enhancement in H+-efflux by 9-fold whereas proline, glutamic acid and lysine showed enhancement by 3, 6 and 1.5- fold respectively. Similar trends in increase in pH after 15 min in SNP treated cells of Candida was observed in presence of all nutrients used. It was demonstrated for the first time that H+-ATPase of C. albicans was affected by NO

Simultaneous shade development, antibacterial, and antifungal functionalization of wool using Punica granatum L. Peel extract as a source of textile dye

In this work, we investigated the use of pomegranate peel extract as an effective functional dye for producing beautiful natural shades on wool and to impart durable antimicrobial properties. Wool is treated with various metal salt mordants in the presence of pomegranate dye under optimum natural dyeing conditions. The structural changes of wool are characterized by SEM and FT-IR techniques. The properties of color strength, color fastness to light, washing, rubbing, and durability of antimicrobial activity to washing are investigated. The experimental results indicate that there is small color variation among shades obtained under identical dyeing conditions. Furthermore, it was found that metal salt mordants improved dyeing depth, fastness properties, and effectively enhanced the durability of antimicrobial activity up to several washing cycles

Effect of sodium nitroprusside on H⁺ -ATPase activity and ATP concentration in <i>Candida albicans</i>

873-879ATP hydrolysis by plasma membrane H+-ATPase from Candida albicans has been investigated in presence of nitric oxide and various nutrients (sugars and amino acids). Sodium nitroprusside (SNP) was used as nitric oxide donor. It was found that ATP concentration decreased in SNP treated cells which was more in presence of sugars like glucose, xylose and 2-deoxy-D-glucose and amino acids as compared to their respective controls. The activity of H+-ATPase from plasma membrane decreased by 70 % in SNP treated cells. Both in vivo and in vitro treatments of SNP showed almost similar effects of decrease in ATPase activity. Effect of SNP was more pronounced in presence of nutrients. Interestingly, it was observed that vanadate did not show any independent effect in presence of nitric oxide. Several workers have reported similar type of results with other P-type A TPases. For the first time, it was observed in the present study that in presence of nitric oxide, H+-ATPase activity decreased like other P-type ATPases. Our study indicated that NO had a significant effect on ATP synthesis and activity of H+- ATPase. In the presence of NO, the ATP concentration was decreased indicating it affected mitochondrial electron transport chain. It may be concluded that NO, not only affects (inhibit) mitochondrial electron transport chain but also interferes with H+- ATPase of plasma membrane by changing its conformation resulting in decreased activity