The L. monocytogenes Scott A strain, a human epidemic isolate, was supplied by the FDA (USA), and the E. coli O157:H7 5947 strain (nontoxigenic) was supplied by the Spanish Type Culture Collection, University of Valencia, Spain. All strains were kept at −80 °C in MicrobankTM vials (PRO-LAB Diagnostics, Neston, Wirrall, UK). Every two months, one of the vials was opened, and the stock culture was grown in Trypticase soy broth (TSB) (Cultimed, Barcelona, Spain) for 24 h at 35 °C and streaked onto PALCAM agar plates (Merck, Darmstadt, Germany), which were incubated for 48 h at 35 °C. One colony obtained in PALCAM agar was transferred to TSB and incubated for 28 h at 35 °C before being stored at −20 °C in a solution of 40% TSB and 60% glycerol until use. The fresh cultures for the experiments were made by incubating one loopful of pure culture in TSB for 24 h at 35 °C. The inocula were standardized in TSB until an optical density (OD) of 0.1 at 595 nm was reached and then diluted in TSB to obtain a bacterial concentration between 5 and 5.7 log CFU/mL. The inocula bacterial populations were counted by spreading suitable diluted aliquots onto Trypticase soy agar (TSA) plates, followed by incubation at 37 °C for 24 h.
Microbanktm vials
Manufactured by Pro-Lab Diagnostics
Sourced in United Kingdom
The MicrobankTM vials are a laboratory product designed for the storage and preservation of microorganisms. These vials provide a convenient and reliable method for maintaining microbial cultures. The core function of the MicrobankTM vials is to facilitate the long-term storage of microorganisms while preserving their viability and characteristics.
Automatically generated - may contain errors
Lab products found in correlation
3 protocols using microbanktm vials
1
Maintenance and Standardization of Bacterial Strains
2
Isolation and Identification of Lactic Acid Bacteria
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
To isolate the LAB, each sample (15 g) was ground aseptically, suspended in Ringer’s solution (135 mL) (Sigma–Aldrich, Milan, Italy), and homogenized in a stomacher (BagMixer 400; Interscience, Saint Nom, France) for 2 min. at maximum speed. The homogenized solution was then serially diluted. Decimal dilutions were plated on de Man, Rogosa, and Sharpe (MRS) agar (Oxoid, Milan, Italy) and incubated under anaerobic conditions at 37 °C for 48 h. After incubation, the colonies (10–15 colonies for each sample) were randomly selected and plated on the MRS agar until pure cultures, identified by colony morphology, were formed. All of the isolates then underwent Gram staining and catalase reactions. Only Gram-positive and catalase-negative samples were selected as LAB and stored in MicrobankTM vials (Pro-Lab Diagnostics, Richmond Hill, ON, Canada) at −80 °C for further analysis.
3
Colistin Resistance in Enterobacterales and Non-fermenters
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
We used 97 isolates from the Enterobacterales order and non-fermenting bacteria from clinical samples in the period from 2016 to 2017 at the clinical microbiology laboratories of the University Hospital Basel, Switzerland; Cantonal Hospital Lucerne, Switzerland and laboratory Viollier in Allschwil, Switzerland (Additional file 1). All colistin resistant isolates tested with Vitek 2® (bioMérieux, Marcy'l Etoile, France) from the University Hospital Basel were included in the study. We used Escherichia coli NCTC-13846 and E. coli KP37 harbouring mcr-1 and mcr-2, respectively, as reference strains (22) . The strain collection also included 43 colistin sensitive isolates.
Species identification was performed at the time of diagnosis with matrix-assisted laser desorption ionization time of flight mass spectrometry MALDI-TOF MS (MALDI-TOF MS; Bruker, Bremen, Germany) by using the mass-spectrum library and the MALDI Biotyper 3 software (OC 3.1, Bruker Daltonics) at standard conditions. All bacterial isolates were frozen at -70 °C in cryogenic Microbank TM vials (Pro-Lab Diagnostics, Birkenhead, UK). Prior to testing, the strains were cultured on Columbia agar supplemented with 5% sheep blood (BD Diagnostic Systems, Allschwil, Switzerland) with subsequent subculture after 24 hours.
Species identification was performed at the time of diagnosis with matrix-assisted laser desorption ionization time of flight mass spectrometry MALDI-TOF MS (MALDI-TOF MS; Bruker, Bremen, Germany) by using the mass-spectrum library and the MALDI Biotyper 3 software (OC 3.1, Bruker Daltonics) at standard conditions. All bacterial isolates were frozen at -70 °C in cryogenic Microbank TM vials (Pro-Lab Diagnostics, Birkenhead, UK). Prior to testing, the strains were cultured on Columbia agar supplemented with 5% sheep blood (BD Diagnostic Systems, Allschwil, Switzerland) with subsequent subculture after 24 hours.
About PubCompare
Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.
We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.
However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.
Ready to get started?
Sign up for free.
Registration takes 20 seconds.
Available from any computer
No download required
Revolutionizing how scientists
search and build protocols!