US Army-Natick Soldier RD&E Center, Warfighter Directorate, Natick, MA, USA.
J Appl Microbiol. 2014 Sep;117(3):711-20. doi: 10.1111/jam.12557. Epub 2014 Jun 23.
Examine effects of different levels and types of nutrient germinant receptors (GRs) and other germination proteins on Bacillus subtilis spore germination by a moderate high pressure (mHP) (150 megaPascals (MPa)) that triggers germination through GRs, and a very high pressure (vHP) (550 MPa) that triggers spore germination independent of GRs.
The Moderate HP (mHP) and vHP germination kinetics of B. subtilis spores with large variations in levels of GRs and other germination proteins, including the GerD protein and the SpoVA proteins that comprise a spore membrane channel that is likely opened by vHP were measured.
GR levels were the major factor determining mHP germination rates. However, other factors modulated mHP germination rates including (i) relative levels of individual GRs (GerA, GerB, GerK), as mHP affected different GRs differently; (ii) levels of a recently identified small protein that may be a GR subunit; and (iii) a dominant negative mutation in gerD that eliminates GR-dependent nutrient germination. In contrast, the alterations in germination proteins had no major effect on vHP germination, except for reduction of SpoVA protein levels.
With the increasing use of HP for food processing, this study provides new information on factors that modulate HP germination of spores for potential application of HP technology to achieve food sterility.
通过适度高压 (mHP)（150 兆帕斯卡 (MPa)）和超高压 (vHP)（550 MPa）来触发枯草芽孢杆菌孢子的萌发，mHP 通过 GR 触发萌发，vHP 则独立于 GR 触发萌发，来研究不同水平和类型的营养体萌发受体 (GRs) 和其他萌发蛋白对枯草芽孢杆菌孢子萌发的影响。
测量了具有不同 GRs 和其他萌发蛋白水平（包括 GerD 蛋白和 SpoVA 蛋白）的枯草芽孢杆菌孢子的 mHP 和 vHP 萌发动力学。
GR 水平是决定 mHP 萌发率的主要因素。然而，其他因素也会调节 mHP 萌发率，包括 (i) 各个 GR（GerA、GerB、GerK）的相对水平，因为 mHP 对不同的 GR 有不同的影响；(ii) 最近发现的一种可能是 GR 亚基的小蛋白的水平；和 (iii) gerD 中的显性负突变，该突变消除了 GR 依赖的营养体萌发。相比之下，除了降低 SpoVA 蛋白水平外，萌发蛋白的改变对 vHP 萌发没有重大影响。
随着高压在食品加工中的应用越来越广泛，本研究为调节孢子高压萌发的因素提供了新信息，为高压技术在实现食品无菌方面的潜在应用提供了依据。
