Evaluating changes to Ralstonia pickettii in high-purity water to guide selection of potential calibration materials for online water bioburden analyzers

Abstract

Online water bioburden analyzers (OWBAs) can provide real-time feedback on viable bacteria in high-purity water (HPW) systems for pharmaceutical manufacturers. To calibrate and validate OWBAs, which detect bacteria using scattered light and bacterial autofluorescence, standards are needed that mimic the characteristics of bacteria in HPW. To guide selection of potential standards, e.g., fluorescent microspheres, a relevant bacterial contaminant, Ralstonia pickettii, was characterized for size, count, viability, and autofluorescence after exposure for 24 h to HPW or a nutrient environment. The cells exposed to HPW showed smaller sizes, with lower counts and autofluorescence intensities, but similar spectral features. The cell characteristics are discussed in comparison with a set of fluorescent microspheres, considering factors relevant to OWBAs. These studies suggest that fluorescent microspheres should be relatively small (< 1 µm diameter) and dim, while covering a broad emission range from ≈ (420 to 600) nm to best mimic the representative R. pickettii.Electronic supplementary materialThe online version of this article (10.1007/s10295-019-02192-4) contains supplementary material, which is available to authorized users.

Oxacillinases and antimicrobial susceptibility of Ralstonia pickettii from pharmaceutical water systems in Croatia

“…It tolerates a wide temperature range, 15-42°C (Anderson et al 1985), can pass through 0Á2 and 0Á22 lm sterilizing grade filters (Anderson et al 1985;Sundaram et al 1999Sundaram et al , 2007Adley et al 2005) and shows resistance to some disinfectants, such as chlorhexidine (Kahan et al 1983;Verschraegen et al 1985). It is oligotrophic, and cryptic growth can help it to survive in Letters in Applied Microbiology 75, 103--113 © 2022 The Society for Applied Microbiology ultra-clean water systems (McAlister et al 2002) where it forms biofilm (Kulakov et al 2002;Adley et al 2005;Benkstein et al 2019). As an opportunistic pathogen, it can become pathogenic and cause infections in immunocompromised patients and its prevalence constantly increases.…”

“…It is often isolated from dialysis systems equipped with chlorinated polyvinyl chloride pipelines (Dombrowsky et al 2013), and colonizes other segments of the hospital environment, including haemodialysis, assisted respiration devices (Vincenti et al 2014), and intravascular catheters (Raveh et al 1993;Pasticci et al 2005;Vincenti et al 2014). It has been isolated from many clinical samples, such as sputum, blood, wound, urine, nose swab, ear swab, cerebrospinal fluid (Benkstein et al 2019;Nasir et al 2019) and has been associated with a wide range of infections in hospitalized immunocompromised patients like bacteremia (Woo et al 2002;Purabi Barman, 2014;Ryan and Adley 2014;Steinmann et al 2014;Tejera et al 2016;Lin et al 2018;Basso et al 2019), pseudobacteremia (Verschraegen et al 1985;Barbut et al 2006) septicemia in adults (Strateva et al 2012), neonatal sepsis (Vitaliti et al 2008;Sharma et al 2017), septic arthritis (Zellweger et al 2004), prosthetic joint infection (Birlutiu et al 2017), osteomyelitis (Wertheim and Markovitz 1992), respiratory infections (Waugh et al 2010), endocarditis (Orme et al 2015) and infections in patients with cystic fibrosis (Coenye et al 2002(Coenye et al , 2005Prior et al 2017). R. pickettii nosocomial colonization and infections are often associated with the use of contaminated solutions that are declared as sterile (Kahan et al 1983;Anderson et al 1985;McNeil et al 1985;Labarca et al 1999;Woo et al 2002;Ryan et al 2006;…”

“…2005; Benkstein et al . 2019). As an opportunistic pathogen, it can become pathogenic and cause infections in immunocompromised patients and its prevalence constantly increases.…”

“…It has been isolated from many clinical samples, such as sputum, blood, wound, urine, nose swab, ear swab, cerebrospinal fluid (Benkstein et al . 2019; Nasir et al . 2019) and has been associated with a wide range of infections in hospitalized immunocompromised patients like bacteremia (Woo et al .…”

Bacterial Species Identified in the Filtrate of Microfiltration Membranes in the Separation of Activated Sludge

“…Among strains under the genus Methylobacterium, which is often associated with biofilm formation on RO membranes [24], M. radiotolerans derived from tap water is known to cause opportunistic infections for hemodialysis patients [31]. The detection of R. pickettii in filtrate is likely because it has been shown to form biofilm in pure water devices [32].…”