Alkaline phosphatase production during sporulation of Bacillus cereus

Electrochemical phagemid assay for the specific detection of bacteria using Escherichia coli TG-1 and the M13KO7 phagemid in a model system

We describe a reporter phagemid system for the specific amperometric detection of bacteria. We constructed a phagemid a bacteriophage containing a bacterial plasmid using the M13KO7 helper phage and a commercial plasmid, pFLAG-ATS-BAP, which contains a gene encoding for a reporter enzyme, alkaline phosphatase. In the bacteria, the enzyme reacts with the substrate, p-aminophenyl phosphate, in the periplamic space that separates the outer plasma membrane from the cell wall. Thus, the activity of the reporter enzyme can be measured directly in an electrochemical cell without further treatment. The product of the enzymatic activity, p-aminophenol, diffuses out and is oxidized at the working electrode with an applied potential of 220 mV vs the reference electrode Ag/AgCl. The lower detection limit was 1 cfu/mL E. coli TG1 in less than 3 h in a very specific manner. The use of plasmid alkaline phosphatase as the reporter increased the sensitivity by 10-fold over our earlier electrochemical lytic phage method. Such a system can be used for the rapid detection of any strain of bacteria using the appropriate bacteriophage and reporter gene.

Activity of hydrolytic enzymes in fungi isolated from diabetic pregnant women: is there any relationship between fungal alkaline and acid phosphatase activity and glycemic control?

Ability to respond to environmental changes and secretion of hydrolases are considered to be important for Candida virulence. In this study we determined and compared the activities of 19 different hydrolases of the fungal strains isolated from diabetic and non-diabetic pregnant women. We also looked for the presence of a relationship between hydrolase activities and glycemic control, and, furthermore, evaluated the influence of gestational age on the activity of hydrolases. Mycological examinations were performed for 119 diabetic pregnant women: 47 with diabetes mellitus type I (DM), 72 with gestational diabetes (GDM), and for 132 healthy women (CON). Samples were collected from the vagina, rectum and oral cavity and cultured on Sabouraud media. The fungal hydrolase activities were evaluated using the API ZYM test (bioMerieux). For the 19 different fungal hydrolases tested, 13 activities were present in the isolated fungal strains. The activity of alkaline phosphatase (ALP) in vaginal strains (p=0.028) and acid phosphatase (ACP) in strains from the vagina (p=0.006) and rectum (p=0.049) was significantly lower in DM than in GDM and CON women. In conclusion, we describe for the first time that fungi isolated from pregnant diabetic women have lower activity of both phosphatases compared to fungi isolated from healthy women. Furthermore, similar differences of mean ALP and ACP activities were observed in the course of pregnancy in strains from the vagina and rectum of DM and CON women. However, strains from DM had lower activity at each stage of pregnancy. The highest activity of ALP and ACP was detected at the beginning, then declined, and had the lowest values between the 24(th) and 33(rd) week of gestation. After that period the activity of both phosphatases increased.