The Elastic Properties of the Cryptococcus neoformans Capsule

被引:33
作者
Frases, Susana [1 ]
Pontes, Bruno [2 ]
Nimrichter, Leonardo [3 ]
Rodrigues, Marcio L. [3 ]
Viana, Nathan B. [2 ,4 ]
Casadevall, Arturo [1 ,5 ]
机构
[1] Albert Einstein Coll Med, Dept Microbiol & Immunol, Bronx, NY 10467 USA
[2] Univ Fed Rio de Janeiro, Inst Ciencias Biomed, LPO COPEA, Rio De Janeiro, Brazil
[3] Univ Fed Rio de Janeiro, Lab Estudos Integrados Bioquim Microbiana, Inst Microbiol Prof Paulo de Goes, Rio De Janeiro, Brazil
[4] Albert Einstein Coll Med, Dept Med, Div Infect Dis, Bronx, NY 10467 USA
[5] Univ Fed Rio de Janeiro, Inst Fis, Rio De Janeiro, Brazil
基金
美国国家卫生研究院;
关键词
ATOMIC-FORCE MICROSCOPY; POLYSACCHARIDE; GLUCURONOXYLOMANNAN; PHAGOCYTOSIS; ANTIBODIES; SURFACE; CELLS; ENLARGEMENT; GROWTH;
D O I
10.1016/j.bpj.2009.04.043
中图分类号
Q6 [生物物理学];
学科分类号
071011 ;
摘要
Microbial capsules are important for virulence, but their architecture and physical properties are poorly understood. The human pathogenic fungus Cryptococcus neoformans has a large polysaccharide capsule that is necessary for virulence and is the target of protective antibody responses. To study the C. neoformans capsule we developed what we believe is a new approach whereby we probed the capsular elastic properties by applying forces using polystyrene beads manipulated with optical tweezers. This method allowed us to determine the Young's modulus for the capsule in various conditions that affect capsule growth. The results indicate that the Young's modulus of the capsule decreases with its size and increases with the Ca2+ concentration in solution. Also, capsular polysaccharide manifests an unexpected affinity for polystyrene beads, a property that may function in attachment to host cells and environmental structures. Bead probing with optical tweezers provides a new, nondestructive method that may have wide applicability for studying the effects of growth conditions, immune components, and drugs on capsular properties.
引用
收藏
页码:937 / 945
页数:9
相关论文
共 36 条
[31]   Regulation of Cryptococcus neoformans capsule size is mediated at the polymer level [J].
Yoneda, Aki ;
Doering, Tamara L. .
EUKARYOTIC CELL, 2008, 7 (03) :546-549
[32]   Induction of capsule growth in Cryptococcus neoformans by mammalian serum and CO2 [J].
Zaragoza, O ;
Fries, BC ;
Casadevall, A .
INFECTION AND IMMUNITY, 2003, 71 (11) :6155-6164
[33]   The polysaccharide capsule of the pathogenic fungus Cryptococcus neoformans enlarges by distal growth and is rearranged during budding [J].
Zaragoza, O ;
Telzak, A ;
Bryan, RA ;
Dadachova, E ;
Casadevall, A .
MOLECULAR MICROBIOLOGY, 2006, 59 (01) :67-83
[34]   Capsule enlargement in Cryptococcus neoformans confers resistance to oxidative stress suggesting a mechanism for intracellular survival [J].
Zaragoza, Oscar ;
Chrisman, Cara J. ;
Castelli, Maria Victoria ;
Frases, Susana ;
Cuenca-Estrella, Manuel ;
Rodriguez-Tudela, Juan Luis ;
Casadevall, Arturo .
CELLULAR MICROBIOLOGY, 2008, 10 (10) :2043-2057
[35]   Monoclonal antibodies can affect complement deposition on the capsule of the pathogenic fungus Cryptococcus neoformans by both classical pathway activation and steric hindrance [J].
Zaragoza, Oscar ;
Casadevall, Arturo .
CELLULAR MICROBIOLOGY, 2006, 8 (12) :1862-1876
[36]   Experimental modulation of capsule size in Cryptococcus neoformans [J].
Zaragoza O. ;
Casadevall A. .
Biological Procedures Online, 2004, 6 (1) :10-14