RRC ID |
40870
|
著者 |
Gerbino E, Carasi P, Araujo-Andrade C, Tymczyszyn EE, Gómez-Zavaglia A.
|
タイトル |
Role of S-layer proteins in the biosorption capacity of lead by Lactobacillus kefir.
|
ジャーナル |
World J Microbiol Biotechnol
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Abstract |
The role of S-layer proteins (SLP) on the Pb(2+) sequestrant capacity by Lactobacillus kefir CIDCA 8348 and JCM 5818 was investigated. Cultures in the stationary phase were treated with proteinase K. A dot blot assay was carried out to assess the removal of SLP. Strains with and without SLP were exposed to 0-0.5 mM Pb(NO3)2. The maximum binding capacity (q max ) and the affinity coefficient (b) were calculated using the Langmuir equation. The structural effect of Pb(2+) on microorganisms with and without SLP was determined using Raman spectroscopy. The bacterial interaction with Pb(2+) led to a broadening in the phosphate bands (1,300-1,200 cm(-1) region) and strong alterations on amide and carboxylate-related bands (νCOO(-) as and νCOO(-) s). Microorganisms without SLP removed higher percentages of Pb(2+) and had higher q max than those bearing SLP. Isolated SLP had much lower q max and also removed lower percentages of Pb(2+) than the corresponding whole microorganisms. The hydrofobicity of both strains dramatically dropped when removing SLP. When bearing SLP, strains do not expose a large amount of charged groups on their surfaces, thus making less efficient the Pb(2+) removal. On the contrary, the extremely low hydrofobicity of microorganisms without SLP (and consequently, their higher capacity to remove Pb(2+)) can be explained on the basis of a greater exposure of charged chemical groups for the interaction with Pb(2+). The viability of bacteria without SLP was not significantly lower than that of bacteria bearing SLP. However, microorganisms without SLP were more prone to the detrimental effect of Pb(2+), thus suggesting that SLP acts as a protective rather than as a sequestrant layer.
|
巻・号 |
31(4)
|
ページ |
583-92
|
公開日 |
2015-4-1
|
DOI |
10.1007/s11274-015-1812-7
|
PMID |
25653110
|
MeSH |
Adsorption
Bacterial Proteins / genetics
Bacterial Proteins / metabolism*
Biodegradation, Environmental
Lactobacillus / genetics
Lactobacillus / growth & development
Lactobacillus / metabolism*
Lead / metabolism*
Membrane Glycoproteins / genetics
Membrane Glycoproteins / metabolism*
|
IF |
2.477
|
引用数 |
40
|
WOS 分野
|
BIOTECHNOLOGY & APPLIED MICROBIOLOGY
|
リソース情報 |
一般微生物 |
JCM 5818 |