HIGH-SPEED ROTATION AND SPEED STABILITY OF THE SODIUM-DRIVEN FLAGELLAR MOTOR IN VIBRIO-ALGINOLYTICUS
HIGH-SPEED ROTATION AND SPEED STABILITY OF THE SODIUM-DRIVEN FLAGELLAR MOTOR IN VIBRIO-ALGINOLYTICUS
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DOI：
10.1006/jmbi.1995.0415
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发表时间：
1995-08-04
影响因子：
5.6
通讯作者：
HOMMA, M
中科院分区：
文献类型：
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作者：
MURAMOTO, K;KAWAGISHI, I;HOMMA, M
溶藻弧菌中由Na+驱动的鞭毛马达旋转非常快。用亚毫秒时间分辨率的激光暗场显微镜测量了单个鞭毛在粘连细胞上的旋转。随着外加NaC l浓度的增加，旋转速度增大，在300 mM的NaC l浓度下，旋转速度达到1000R.P.S。分析了在不同转速下(从接近50RP.S到接近1000RPS)不同转速下(从接近50RPS到接近1000RPS)不同转速下旋转周期的波动，这些变化是通过改变外界的氯化钠浓度以及添加原载体或特定的抑制剂来改变的。在高转速下(400RP.S.以上)，观察到的旋转是稳定的，tau sigma((Tau))的标准偏差在平均旋转周期(<；tau>；)的7%到16%之间。在低转速下(100RP.S以下)，旋转周期趋于波动，tau的分布呈非高斯分布。Sigma(Tau)的值在10%到30%之间。然而，由于鞭毛纤维的旋转扩散，在不同转速下观测到的sigma(Tau)的最小值近似等于计算的标准偏差。这些结果表明，在不同的Na+通过马达内流时，扭矩是稳定产生的。我们观察到了无法用旋转扩散解释的巨大波动。我们讨论了导致大幅波动的因素。(C)1995年学术出版社有限公司
The Na+-driven flagellar motor in Vibrio alginolyticus rotates very fast. Rotation of a single flagellum on a stuck cell was measured by laser darkfield microscopy with submillisecond temporal resolution. The rotation rate increased with increasing external concentration of NaCl, and reached 1000 r.p.s, at 300 mM NaCl. The Na+ influx through the motor should determine the rotation period (tau) and affect the speed stability Fluctuation of the rotation period was analyzed at various rotation rates (from similar to 50 r.p.s, to similar to 1000 r.p.s.), which were changed by changing the external concentration of NaCl and the addition of a protonophore or a specific inhibitor. At high rotation rates (over 400 r.p.s.), the observed rotation was stable, and the standard deviation of tau sigma((tau)) ranged from 7% to 16% of the average rotation period (< tau>). At low rotation rates (under 100 r.p.s), the rotation period tended to fluctuate, and the distributions of tau were non-Gaussian. The value of sigma(tau) ranged from 10 to 30% of . However, the observed minimum value of sigma(tau) at various rotation rates was approximately equal to the calculated standard deviation due to the rotational diffusion of the flagellar filament. These results suggest that the torque was stably generated at various Na+ influxes through the motor. We observed large fluctuations that cannot be explained by rotational diffusion. We discuss the factors that induce the large fluctuation. (C) 1995 Academic Press Limited