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β-Endorphin is known to stimulate phospholipase production by Malassezia pachydermatis during canine dermatoses. The role of β-endorphin in Malassezia infection in humans is not well studied. The present study compares the influence of β-endorphin on Malassezia globosa and Malassezia restricta isolated from patients with seborrhoeic dermatitis/dandruff (SD/D) and healthy controls. Malassezia isolates (five each of the two species from patients and healthy controls) were grown on modified Dixon's agar with or without 100 nmol/L β-endorphin. Phospholipase activity was quantified based on its ability to hydrolyze L-α-phosphatidylcholine dimyristoyl (phospholipid substrate). Free fatty acid was measured by a colorimetry method. In isolates from patients, the phospholipase activity significantly increased after exposure to β-endorphin (M. globosa, P = .04; M. restricta, P = .001), which did not occur in isolates from healthy controls. Moreover, after β-endorphin exposure the patient isolates had significantly higher (P = .0004) phospholipase activity compared to the healthy control isolates. The results suggest that isolates of M. globosa and M. restricta from patients may differ from those of healthy humans., (© The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Classical lipases are well known for being enzymes hydrolysing triacylglycérols as substrate, except the porcine pancreatic lipase (PPL) which was able to hydrolyze phosphatidylcholine. Amino acid sequence alignments revealed that Valine 260 residue in PPL lid, postulated to be responsible for the PPL phospholipase activity, was present in the Turkey pancreatic lipase (TPL). The importance of Val 260 in the phospholipase activities expression has been reported. To confirm this fact, Val 260 was mutated to Alanine in the TPL lid. Mutated protein has conserved its phospholipase activity as well as the non mutated TPL. Therefore, Valine 260 residue in the lid is not involved in the pancreatic lipases phospholipase activity. The rTPL phospholipase activity was also studied using monolayer technique. This avian pancreatic lipase has shown phospholipase activity toward differently charged phospholipids. The highest phospholipase activity was found on phosphatidylglycerol (negatively charged substrate) at a surface pressure of 20mN/m, but when a zwitterionic substrate was used (DLPC), a lower activity was found at a surface pressure of 10mN/m. However, it is worth noticing that the TPL phospholipase activity is about 100 fold lower than its lipase activity. GC chromatography analyses of the released fatty acids from the hydrolysis of 1,2-POPC have shown that rTPL hydrolyses esters bonds at the sn-1 as well as the sn-2 position of phospholipids. Hence, rTPL shows a low phospholipase activity in comparison to its activity toward triacylglycerols., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Malassezia pachydermatis is part of the skin microbiota of dogs and cats. M. pachydermatis has been associated with external otitis and seborrhoeic dermatitis, reported more often in dogs than in cats. When the physical, chemical or immunological mechanisms of the skin are altered, M. pachydermatis could act as a pathogen. Thus, several virulence factors, such as the ability to produce esterase, lipase, lipoxygenase, protease, chondroitin sulphatase, and hyaluronidase, have been studied., Aims: In the present study, we aim to identify the phospholipase activity measured at pH 6.3, and the proteinase activity measured at pH 6.3 and pH 6.8 (pH from ears of dogs with external otitis) of M. pachydermatis strains isolated from dogs with and without external otitis., Methods: The phospholipase activity was measured using a semi-quantitative method with egg yolk, and the proteinase activity with a semi-quantitative method using bovine serum albumin agar. The study was performed on 96 isolates of M. pachydermatis, 43 isolated from dogs without clinical symptoms of otitis, and 52 isolated from dogs with otitis., Results: In our study, 75.8% of the isolates showed phospholipase activity at pH 6.3, and 81 and 97.9% of them showed proteinase activity measured at pH 6.3 and 6.8, respectively. A higher phospholipase activity was detected in strains isolated from dogs with otitis. The proteinase activity was increased at a pH of 6.8 (97.9%) in comparison to a pH of 6.3 (81%)., Conclusions: Our results suggest that the phospholipase activity may play an important role in the invasion of host tissues in chronic canine otitis cases. The proteinase activity results obtained in this study suggest that a reduction in the pH of the treatment may improve its efficacy in the resolution of M. pachydermatis otitis., (Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.)

Enzymatic activity is important characteristic of enzymes for industrial application, which can be improved by protein engineering. PLA1 is a biocatalyst applied in phospholipid modification for its phospholipase activity and had obtained board attention for its application in oil degumming. Bioinformatics analysis suggested that three charged residues, R81, R84, and E87 located in the lid of the protein, may affect the conformational change of lid thus influence the activity of the enzyme. In the current study, mutagenesis of these residues was conducted with protein engineering. Five mutants such as R81A, R84A, R84M, R84K, and E87Q with higher phospholipase activity were screened out. Biochemical properties analysis showed that all of them had identical optimal pH value with wild-type, while the optimal temperature was decreased to be 50°C and the kcat /KM was improved. Degumming soybean oil, three of five mutants, R81A, R84M, and E87Q, decreased phosphorous content lower than 8.3 mg/kg within 3 h, which was highly improved compared with wild-type. R84M decrease phosphorus content less than 5 mg/kg within 5 h. These findings not only permit optimization of enzyme performance in degumming but also shed light on the application of bioinformatics techniques and protein engineering techniques on industry application. Practical applications: The results support that design proteins according to bioinformatics and protein engineering is desirable and the phospholipase with higher activity is more suitable for oil degumming. The phospholipase activity of PLA1 can be improved by protein engineering based on bioinformatics analysis. With its properties of hydrolyzing sn-1 position ester bond of phospholipids, nonhydratable phospholipids were converted into their hydratable forms, PLA1 can be applied in oil degumming. PLA1 with higher phospholipase activity is more likely to suitable for oil degumming since it could decrease the phosphorous content of oil lower than 10 mg/kg within shorter reaction, which showed great potencial for degumming application. [ABSTRACT FROM AUTHOR]

Background and Aim: Candida spp. have emerged as successful pathogens both in invasive and mucosal infections. C. albicans is the sixth cause of most common nosocomial infections according to studies by the Centers for Disease Control and Prevention. A shift toward non-albicans species has been reported. There is a dearth of knowledge regarding the virulence factors of Candida, especially from this part of India. The aim was to study the prevalence of Candida, speciate, and determine antifungal sensitivity along with the detection of in vitro production of phospholipases in 100 Candida isolates. Materials and Methods: A total of 100 Candida isolates from various clinical specimens were studied (February 1, 2015-May 31, 2015; 4 months). Speciation was done by conventional methods and antifungal drugs fluconazole and voriconazole tested. Phospholipase activity (Pz value) was determined. Results: Of the 100 Candida spp., 35% were C. albicans and 65% were nonalbicans Candida (NAC). Species spectrum was of the 100 isolates as follows: 35 were C. albicans, 17 Candida tropicalis, 6 Candida glabrata, 8 Candida guilliermondi, 1 Candida kefyr, 6 Candida krusei, 14 Candida parapsilosis, 2 Candida lusitaniae, and 1 Trichosporon and 10 Candida spp. (not speciated). Phospholipase production was seen in 81 (81%) of the total isolates. The majority (63%) of phospholipase producers were NAC. Among NAC spp., the maximum phospholipase activity was seen in C. tropicalis (30%) and C. parapsilosis (24%). Of these, 60% of Candida was from patients admitted to the hospital. Sensitivity rates of C. albicans for fluconazole and voriconazole were 89.5% and 90.5%, respectively. Conclusion: Increasing usage of devices, total parenteral nutrition, broad-spectrum antibiotics, chemotherapies, and transplantation are factors contributing to the increase of candidal infections. Recent studies underline the increasing frequency of infections by NAC. The present study showcases the increased prevalence as well as virulence of NAC. In addition, early detection of virulence factors by Candida is useful in clinical decision-making [ABSTRACT FROM AUTHOR]

Copyright of Revista Iberoamericana de Micologia is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Iberoamericana de Micologia is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Over the past years, the incidence of yeast infections, especially candidiasis, has increased. It is known that birds, including cockatiels, harbor potentially pathogenic yeasts to human beings in their gastrointestinal tract. Thus, this work aims at determining the in vitro antifungal susceptibility and phospholipase activity of Candida spp. isolated from the gastrointestinal tract and stools of cockatiels. Sixty cockatiels were assessed and samples were collected from oral cavity, crop and cloaca and stools were collected from cages where birds were kept. Yeast species were identified according to morphological and biochemical characteristics. Amphotericin B, itraconazole and fluconazole were tested against 39 C. albicans; 12 C. tropicalis; 7 C. parapsilosis and 1 C. krusei, through broth microdilution test. These same isolates were also tested for phospholipase production, on egg yolk agar. For amphotericin B, itraconazole and fluconazole, MICs were 0.25–1μg/mL, 0.03125 to ≥16μg/mL and 0.5 to ≥64μg/mL, respectively, and resistance to itraconazole and fluconazole was observed in 14 (35.89%) and 4 (10.26%) C. albicans isolates, respectively. All C. albicans were positive for phospholipase production, out of which 74.36% presented high enzymatic activity. Among non-albicans Candida species, 40% produced phospholipase. The results show that cockatiels might represent a hazard to human health, as sources of infections caused by resistant Candida spp., especially to immunocompromised individuals, children and elderly. [ABSTRACT FROM AUTHOR]

To investigate the prevalence of C'ryptococcus in droppings from captive birds in Chile, dry droppings from 113 captive birds of various species were cultured for Cryptococcus neoformans. The yeast was recovered from 17 of the 113 samples (15% [95% confidence intervals, 8.4%-2 1 .6%]). Other yeast organisms recovered from psittacine bird droppings were Cryptococcus albidus and Cryptococcus uniguttulatus. Secreted phospholipase has been proposed as a virulence determinant in C neoformans. Phospholipase production by the egg yolk plate method, and in vitro susceptibility to fluconazole by using the disk diffusion test were performed on 17 Cneoformans isolates. Two of the 17 strains (11.7%) did not produce phospholipase. Two (11.7%) were resistant to fluconazole, and 5 of 17 (29.4%) were susceptible dose-dependent. The Cryptococcus species isolated from droppings from captive birds could be potential pathogens in humans. [ABSTRACT FROM AUTHOR]

c-Fos, a component of AP-1 transcription factors, has been shown to have marked amphitropic properties and to regulate phospholipase activity against lipid monolayers. In agreement with its high surface activity, it has also been found to associate to membranes of the endoplasmic reticulum and to activate phospholipid metabolism in vivo. All these findings point to an involvement of this oncoprotein within a membrane environment. We have previously shown that c-Fos modulates in different manners the activity of phospholipase A2 and phospholipase C against monolayers of dilauroylphosphatidylcholine (PC). In this work, we have studied the possible molecular mechanism underlying the phosphohydrolytic modulation. Our results show that c-Fos expands and hyperpolarizes PC, indicating that its effects on these enzymatic activities are due to the changes it induces on the interfacial organization of the substrate. [Copyright &y& Elsevier]