The AccuPRO-ID^® proteotypic bacterial identification service is the ideal choice for routine environmental monitoring and primary screening of bacterial organisms

Dated biochemical technologies typically lack the library entries and detection capabilities to keep pace with today’s constantly changing taxonomy requirements. The AccuPRO-ID^® service combines MALDI-TOF (Matrix assisted laser desorption/ionization – time of flight) mass spectrometry technology and utilizes ribosomal proteins for identification since they are always present in the cell in very high numbers. The testing process yields a unique protein spectral fingerprint that is then compared to a validated database for identification and a 21 CFR Part 11 compliant report is generated. Any sample unidentified by MALDI-TOF is automatically tested, at no extra cost, by our genetic AccuGENX-ID™ 16S sequencing process. This ensures the utmost accuracy for a species level ID, the highest reportable rate, at affordable pricing.

Our MALDI-TOF Process

 

	Source Sample: A very small amount of a single isolated viable bacterial cell material is needed. Samples may be submitted on plates, slants or other traditional media or as an ethanol preparation
	Sample Extraction and Application: Cell material can be lifted from the media and smeared directly onto the target area of the analysis plate (direct sampling method) or samples can be simply taken from the ethanol preparation (extraction method)
	Matrix crystallization mix: Matrix is applied to each smeared sample. A key component of the matrix is a UV-absorbing molecule that protects the proteins for intact protein analysis
	Data Acquisition: Multiple laser pulses initiate the sampling process. Ionized proteins travel towards the detector at different speeds based on their mass and charge
	Data Analysis: Protein peaks that are generated are compared to Accugenix’s extensive database and the results are interpreted by our skilled staff of data analysts
	Quality Assurance Review: Each identification report is reviewed by Quality Assurance

 

Performance Validation

For MALDI-TOF performance validation, Accugenix chose an organism set consisting of 31 representative bacterial species (acquired from ATCC and DSMZ) and 146 different strains representing 43 of the most frequently identified species observed in pharmaceutical manufacturing environments. Identities of all organisms and strains were verified using Accugenix 16S rDNA sequencing method. The results demonstrated that MALDI-TOF resulted in accurate species level identification in most cases, with an exceptionally low rate of species being misidentified (<2%). The samples were processed using both the direct and ethanol preparation methods.  Approximately 30% of the samples gave no ID or did not produce analyzable spectra. These samples would be reprocessed with 16S rDNA sequencing at no additional charge as part of the AccuPRO-ID^® offering.

Real World Case Studies

Comparative blinded studies have been performed with samples analyzed with phenotypic methods performed by clients and with AccuPRO-ID^® performed by Accugenix. These data strongly support the assertion that the AccuPRO-ID^® solution is a highly accurate, fast and inexpensive outsourcing option for routine environmental monitoring programs. You can view the results of one these studies in our knowledge center and AccuPRO-ID vs. VITEK Case Studies for a full discussion.