title: Evaluation of the cell growth of mycobacteria using Mycobacterium smegmatis mc2 155 as a representative species.
abstract: The study of the in vitro cell growth of mycobacteria still remains a fastidious, difficult, and time-consuming procedure. In addition, assessing mycobacterial growth in the laboratory is often complicated by cell aggregation and slow growth-rate. We now report that the use of a stainless steel spring in the culture led to an absence of large cell clumps, to a decrease of dead cells in the exponential phase and to growth of a more homogeneous population of large cells. We also report that flow cytometry is a rapid, simple and reliable approach to monitor mycobacterial cell growth and viability. Here, we monitored Mycobacterium smegmatis cellular growth by optical density, dry cell mass, and colony forming units; in addition, viability, cell size and granularity profiles were analyzed by flow cytometry, and cell morphology by electron microscopy. Cultures monitored by flow cytometry may lead to a better understanding of the physiology of mycobacteria. Moreover, this methodology may aid in characterizing the cell growth of other fastidious species of microorganisms.
authors: Departamento de Microbiologia, Escuela Nacional de Ciencias Biologicas, IPN, Prolong. Carpio y Plan de Ayala s/n, Col. Casco de Santo Tomas, Mexico, D.F., 11340, Mexico. jgonzal1212@yahoo.com.mx
authors: Jorge A
authors: JA
authors: Gonzalez-Y-Merchand
authors: Ruben
authors: R
authors: Zaragoza-Contreras
authors: Rosalina
authors: R
authors: Guadarrama-Medina
authors: Addy C
authors: AC
authors: Helguera-Repetto
authors: Sandra
authors: S
authors: Rivera-Gutierrez
authors: Jorge F
authors: JF
authors: Cerna-Cortes
authors: Leopoldo
authors: L
authors: Santos-Argumedo
authors: Robert A
authors: RA
authors: Cox
mesh_terms: D001431:Bacteriological Techniques / Q000379:methods*; D003470:Culture Media / Q000737:chemistry*; D005434:Flow Cytometry; D050296:Microbial Viability; D020102:Mycobacterium smegmatis / Q000254:growth & development*; D013193:Stainless Steel
chemical_list: D003470:Culture Media; D013193:Stainless Steel