Pharmaceutical care for a case of infective endocarditis caused by Micrococcus luteus complicated with severe pneumonia / 中国药房

OBJECTIVE To provide ideas and reference for the treatment and pharmaceutical care of infective endocarditis （IE） caused by Micrococcus luteus complicated with severe pneumonia. METHODS The clinical pharmacist participated in the treatment of a patient with IE caused by M. luteus complicated with severe pneumonia； all anti-infective treatment plans were agreed upon after the doctor invited the clinical pharmacist for consultation. After the implementation of the plan， the clinical pharmacist conducted pharmaceutical care of effectiveness and safety for the plan， including adopting suitable drug， adjusting the dose of vancomycin by using parameters such as steady-state valley concentration and creatinine clearance rate， monitoring renal function and adverse drug reactions. RESULTS IE caused by M. luteus was cured after surgery and full treatment with anti-bacterial drugs， the severe pneumonia was improved， and the decline of renal function caused by drugs and the primary disease were recovered； clinical pharmacists had ensured the effect of anti-infection treatment by assisting in the formulation of treatment plans and the implementation of pharmaceutical care， avoiding further renal damage and solving the problem of cefoperazone sulbactam- related drug fever. CONCLUSIONS IE caused by M. luteus is relatively serious， and the treatment drug can be vancomycin and rifampicin. During the treatment， it is necessary to monitor the renal function， and adjust the dose of vancomycin or change other drugs； anti-infection pharmaceutical care provided by clinical pharmacists can guarantee the effectiveness and safety of anti- infection plan， and avoid the occurrence of severe adverse drug reactions.

Preparation and characterization of polyhydroxyalkanoate bioplastics with antibacterial activity / 生物工程学报

Polyhydroxyalkanoates (PHAs), as a novel class of biopolymer, are attracting more attention due to their diverse material properties and environment-independent biodegradability. Here we report the preparation of PHA exhibiting efficient antibacterial activity by embedding Nisin, a food additive generally recognized as safe, into poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx), a type of PHA with high biocompatibility. We first prepared Nisin-containing PHBHHx films using solvent casting method. Confocal laser scanning microscopy analysis showed that a well-mixed integrated structure of the films with an even distribution of the Nisin particles in the PHBHHx matrices. Then the antimicrobial activity of PHBHHx/Nisin films against Micrococcus luteus was quantified on agar plate by measuring the size of inhibition zone. Cultivation in liquid media further confirmed the releasing of Nisin from the films and the long-time antibacterial activity. Results showed that the threshold of Nisin concentration for long-time and effective inhibition against bacteria growth is 25 μg/g. These results altogether establish a technological foundation for the application of PHA in biomedicine and food industry.

Keratinolytic abilities of Micrococcus luteus from poultry waste

Keratinolytic microorganisms have become the subject of scientific interest due to their ability to biosynthesize specific keratinases and their prospective application in keratinic waste management. Among several bacterial classes, actinobacteria remain one of the most important sources of keratin-degrading strains, however members of the Micrococcaceae family are rarely scrutinized in regard to their applicatory keratinolytic potential. The tested Micrococcus sp. B1pz isolate from poultry feather waste was identified as M. luteus. The strain, grown in the medium with 1–2% chicken feathers and a yeast extract supplement, produced keratinases of 32 KU and lower level of proteases, 6 PU. It was capable to effectively decompose feathers or “soft” keratin of stratum corneum, in contrast to other “hard” hair-type keratins. The produced keratinolytic enzymes were mainly a combination of alkaline serine or thiol proteases, active at the optimum pH 9.4, 55 °C. Four main protease fractions of 62, 185, 139 and 229 kDa were identified in the crude culture fluid. The research on the auxiliary role of reducing factors revealed that reducing sulfur compounds could be applied in keratinolysis enhancement during enzymatic digestion of keratin, rather than in culture conditions. The presented M. luteus isolate exhibits a significant keratinolytic potential, which determines its feasible applicatory capacity towards biodegradation of poultry by-products or formulation of keratin-based feed components.

Biosynthesis of silver nano-particles by the bacterium micrococcus luteus.

Nanotechnology is the application of science to control matter at the molecular level. It is a field that is burgeoning in the recent times, making an impact in all spheres of human life. Microorganisms play an important role in the eco-friendly synthesis of metal nanoparticles. The use of microorganisms for the synthesis of nanoparticles in the lime light of modern nanotechnology is a novel approach. Biological methods of synthesis have paved the way for the greener synthesis of these nanoparticles which can have application in biomedical sciences. In this study, we report the synthesis of nanoparticles of silver by the reduction of aqueous Ag+ by a culture of Micrococcus luteus. The formation of silver nano-particles was monitored by X-ray diffraction spectroscopy (XRD) and elucidated by transmission electron microscopy (TEM).

Validación de la técnica para la cuantificación de tilosina en un producto sólido / Validation of technique for the quantification of tylosin in a solid product

Se validó la técnica para la cuantificación de tilosina en polvo, para lo cual previamente se estandarizó la técnica recomendada por la United States Pharmacopeia versión 30 del 2007, con el fin de ajustarse y dar cumplimiento a la normativa internacional. La muestra se compuso del 10 por ciento de tilosina fosfato y 90 por ciento de Carrier 40-60. El microorganismo sometido a prueba fue Micrococcus luteus ATCC 9341 y se empleó el método de difusión en agar. Los resultados de las pruebas se sometieron al programa de validación microbiológica "Validation Manager". El método de difusión en agar cumplió con los valores esperados, y así quedó validada la técnica.

The quantification technique of powdered tylosin was validated. To this end, the technique recommended by the United States Pharmacopeia, 30th version, 2007 was standardized to adapt it to and to comply with the international regulations. The sample was composed of 10 percent tylosin phosphate and 90 percent Carrier 40-60. The agar diffusion was used to test the micro-organism Micrococcus luteus ATCC 9341 and all results were microbiologically validated by the program "Validation Manager". The agar diffusion method met the prospective values, thus validating the technique.

Effects of Micrococcus luteus Rpf and Rpf domain protein on growth of Mycobacterium tuberculosis / 中华微生物学和免疫学杂志

Objective To purify Micrococcus luteus Rpf and Rpf domain fusion protein, and to in-vestigate its effects on growth of Mycobacterium tuberculosis. Methods The recombinant plasmids pPro-EXHT-Rpf and pPro-EXHT-Rpf domain were expressed in E. Coli DHSa and then purified under denaturing condition via Ni-NTA purification system and confirmed by Western blot. The biochemical property of the M. Luteus Rpf and Rpf domain was analyzed by stimulating the resuscitation of M. Tuberculosis H37Ra which were in non-culturable' condition. Results The Rpf and Rpf domain products achieved 95% and 93% pure respectively, and the molecular weight was 30 x 103 and 12 x 103, the yield of purification was about 471 mg/L and 337 mg/L of the culture. The M. Luteus Rpf and Rpf domain from the E. Coli showed activity of stimulating the resuscitation of M. Luteus and M. Tuberculosis H37Ra in non-cuhurable' condition which could be inhibited by monoclonal antibodies of M. Luteus Rpf domain remarkably. Conclusion It was dem-onstrated that the purification of Rpf and Rpf domain have high biological activity for further functional, pharmacological and clinical investigations, and M. Luteus Rpf domain protein is fully active as M. Lateus full-length Rpf.

Gene Expression of the Micrococcus luteus Fibrinolytic Enzyme (MLFE) in Bacillus subtilis WB600 / 微生物学通报

MLFE (Micrococcus luteus fibrinolytic enzyme) is a fibrinolytic enzyme produced by Micrococcus luteus ML909 strain. The promoter and signal peptide-coding sequence of ?-amylase gene from Bacillus amyloliquefaciens DC-4 was cloned and fused to the sequence coding for mature peptide of MLFE (Gen-Bank: EU232121), forming the fusion gene called amymlfe. This hybrid gene was inserted into the Escherichia coli-Bacillus subtilis shuttle plasmid vector pSUGV4 and expression plasmid pSU-AmyMLFE was constructed. After transformation with B. subtilis WB600, transformant WB600/pSU-AmyMLFE was obtained and produced clear hydrolyzed zones on fibrin plates. The fibrinolytic activity in supernatants of WB600/pSU-AmyMLFE fermented for 24 hours was tested and found to be 238 UKU/mL. The results of SDS-PAGE analysis showed that there was indeed recombinant protein in supernatants. The Western blotting showed that the molecular weight of the expressed protein was the same as expected. These results indicate that the gene, amymlfe, is successfully expressed in B. subtilis WB600.

Bioavailability and bioequivalence of erythromycin ethylsuccinate granules in healthy volunteers / 中国感染与化疗杂志

Objective To study the bioavailability and bioequivalence of erythromycin ethylsuccinate granules in healthy male volunteers.Methods In a randomized two-period crossover study,20 healthy male volunteers received single 500 mg test and reference formulations of erythromyein ethylsuccinate granules.The plasma concentrations of erythromycin were assayed by microbiological method.Results The parameters of test and reference preparations were as follows:T_(max)(0.86?0.22)and (0.80?0.13)h,C_(max)(2.13?0.64)and(2.16?0.61)mg/L,t_(1/2)(2.04?0.2)and(1.97?0.4)h,AUC_(0-t)(4.96?1.73)and(4.63?1.52)mg?h/L,respectively.There was no significant difference between the two preparations.The rela- tive bioavailahility of the test granules was(109.1?22.8)%.Conclusions The two preparations of erythromycin ethylsucci- nate granules are bioequivalent.

Observations of Infection Structures after Inoculation with Colletotrichum orbiculare on the Leaves of Cucumber Plants Pre-inoculated with Two Bacterial Strains Pseudomonas putida or Micrococcus luteus

Infection structures were observed at the penetration sites on the leaves of cucumber plants inoculated with Colletotrichum orbiculare using a fluorescence microscope. The cucumber plants were previously drenched with suspension of bacterial strains Pseudomonas putida or Micrococcus luteus. The plants pre-inoculated with both bacterial strains were resistant against anthracnose after inoculation with C. orbiculare. To investigate the resistance mechanism by both bacterial strains, the surface of infected leaves was observed at the different time after challenge inoculation. At 3 days after inoculation there were no differences in the germination and appressorium formation of conidia of C. orbiculare as well as in the callose formation of the plants between both bacteria pre-inoculated and non-treated. At 5 days, the germination and appressorium formation of the fungal conidia were, however, significantly decreased on the leaves of plants pre-inoculated with M. luteus at the concentration with 1.0 x 10(7) cfu/ml. Furthermore, callose formation of plants cells at the penetration sites was apparently increased. In contrast, there were no defense reactions of the plants at the concentration with 1.0 x 10(6) cfu/ml of M. luteus. Similarly, inoculation P. putida caused no plant resistance at the low concentration, whereas increase of callose formation was observed at the higher concentration. The results of this study suggest that the resistant mechanisms might be differently expressed by the concentration of pre-treatment with bacterial suspension.

Microbiological Methodology for Detecting Plasma Doxycycline / 中国药房

AIM:To develop a microbiological method for determining plasma doxycyclineMETHODS:Plasma concentration of doxycycline was detected with Staphylococcus aureus ATCC 26003 and Micrococcus luteus ATCC 28001 strains in a variety of culture media and pHsRESULTS:Linear scope of doxycycline(016～100mg/L,r=09 985) could be achieved with using a microbiological method,which consisted of staphylococcus aureus and bovine heart soup culture medium at pH 50CONCLU_SION:This method can be used in study of pharmacokinetics and bioavailability of doxycycline

Cloning and Analysis of Genes Correlated to Trehalose Biosynthesis from Micrococcus luteus / 微生物学通报

Genes related to trehalose biosynthesis from a bacterial strain Micrococcus luteus which can convert partially hydrolyzed starch into trehalose were cloned.Full sequence of gene (MtreY) encoding trehalose maltooligosyl trehalose synthase (MTSase) and partial sequence of gene (MtreZ) encoding maltooligosyl trehalose trehalohydrolase (MTHase) were got using PCR combined non-random shotgun method.Sequence analysis of MtreY predicts a 2370bp open reading frame encoding a protein of 790 amino acids with a predicted molecular weight of 86734 Da.Homologous analysis shows that this new gene has the same conservative motifs with ?-amylase family enzymes.The MtreY gene was expressed in E.coli, and the expression product has the anticipative enzyme activity.