Review

40 KKU Science Journal Volume 39 Number 1 Review
and Waltho, 1962) °“√‡æ‘Ë¡ª√‘¡“≥‚æ·∑ ‡´’¬¡‰ÕÕÕπ
(K+) ¿“¬„π‡´≈≈å¢ÕßÕ“√凧’¬Õ∫‡§Á¡Õ“»—¬°“√∑”ß“π
√«¡°—π√–À«à“ß·∫§∑’√‘‚Õ‚√¥Õª´‘π·≈– ATPase
·∫§∑’√‘‚Õ‚√¥Õª´‘π∑”Àπâ“∑’Ë¢π àß‚æ√∑ÕπÕÕ°®“°
‡´≈≈å„π ¿“«–∑’Ë¡’· ß ∑”„À⇰‘¥§«“¡·µ°µà“ߢÕß
‚æ√∑Õπ¿“¬„π°—∫¿“¬πÕ°‡´≈≈å (proton gradient)
·≈–‡°‘¥°“√‰À≈°≈—∫¢Õß‚æ√∑Õπ∫√‘‡«≥ ATPase À√◊Õ
Na + /H + antiporter ¢≥–°“√π”‚æ√∑Õπ‡¢â“‡´≈≈å∑’Ë
∫√‘‡«≥ Na + /H + antiporter ®–‡°‘¥°“√¢π àß‚´‡¥’¬¡
‰ÕÕÕπÕÕ°®“°‡´≈≈åºà“π∑“ß Na + /H + antiporter ‡àπ
°—π ·≈–¡’°“√π”‚æ·∑ ‡´’¬¡‰ÕÕÕπ‡¢â“‡´≈≈å·∫∫
°“√·æ√à (passive transport) ºà“π uniport ∑’Ë∫√‘‡«≥
‡´≈≈凡¡‡∫√π ‡æ◊ËÕ„À⇰‘¥ ¡¥ÿ≈∑“ߪ√–®ÿ¿“¬„π‡´≈≈å
(electroneutrality) (Lanyi and Hilliker, 1976)
”À√—∫Õ“√凧’¬Õ∫‡§Á¡∑’ˉ¡à¡’·∫§∑’√‘‚Õ‚√¥Õª´‘π
‡àπ Haloferax valcanii ®–π”‚æ·∑ ‡´’¬¡‰ÕÕÕπ
‡¢â“‡´≈≈å‚¥¬«‘∏’ Active transport ‚¥¬„â ATP-driven
transport system (Meury and Kohiyama, 1989) „πªï
2000 Ng ·≈–§≥– »÷°…“®’‚π¡¢Õß Halobacterium
strain NRC-1 æ∫«à“πÕ°®“° Na + /H + antiporter ∑’Ë∑”
Àπâ“∑’Ë¢π àß‚´‡¥’¬¡‰ÕÕÕπÕÕ°®“°‡´≈≈å ¬—ßæ∫
∫√‘‡«≥Õ◊Ëπ∑’Ë∑”Àπâ“∑’Ë¢π àß‚´‡¥’¬¡‰ÕÕÕπ §◊Õ NhaC
proteins ·≈–§âπ§∫√–∫∫°“√π”‡¢â“‚æ·∑ ‡´’¬¡
‰ÕÕÕπ 2 ·∫∫ §◊Õ Passive transport ·≈– Active
transport (ATP-driven transport system, KdpABC
·≈– TrkAH )
2. ‡æ‘Ë¡°“√π”‡¢â“À√◊Õ —߇§√“–Àå “√≈–≈“¬∑’Ë
∑”Àπâ“∑’Ë√—°…“ ¡¥ÿ≈·√ߥ—πÕÕ ‚¡µ‘°√–À«à“ß¿“¬„π
°—∫¿“¬πÕ°‡´≈≈å (Accumulation of Compatible
solutes by transport or synthesis)
“√∑’Ë∑”Àπâ“∑’Ë√—°…“ ¡¥ÿ≈·√ߥ—πÕÕ ‚¡µ‘°
√–À«à“ß¿“¬„π°—∫¿“¬πÕ°‡´≈≈åÕ“√凧’¬®—¥‡ªìπ “√∑’Ë¡’
¢π“¥‡≈Á°·≈–‰¡à¡’º≈µàÕ°“√‡®√‘≠‡µ‘∫‚µ¢Õ߇´≈≈å ®÷ß
∑”„Àâµ√«®æ∫§«“¡‡¢â¡¢âπ¢Õß “√¥—ß°≈à“«¿“¬„π‡´≈≈å
Õ“√凧’¬ª√‘¡“≥ Ÿß ‚¥¬‡©æ“– “√∑’Ë¡’À¡Ÿàøíß°å—π‡ªìπ≈∫
®– “¡“√∂‡¢â“‰ª‡°‘¥æ—π∏–‰ÕÕÕπ‘°°—∫‚æ·∑ ‡´’¬¡
‰ÕÕÕπ ‡√’¬°«à“ Counter ions °—∫ K + ¥—ßπ—Èπ°“√‡æ‘Ë¡
¢÷Èπ¢Õß “√∑’Ë∑”Àπâ“∑’Ë√—°…“ ¡¥ÿ≈·√ߥ—πÕÕ ‚¡µ‘°
√–À«à“ß¿“¬„π°—∫¿“¬πÕ°Õ“√凧’¬®–‡ªìπÕ—µ√“ à«π
°—∫ª√‘¡“≥‚æ·∑ ‡´’¬¡‰ÕÕÕπ ‡æ◊ËÕ„À⇰‘¥ ¡¥ÿ≈¢Õß
§«“¡‡¢â¡¢âπ¢Õß “√≈–≈“¬¿“¬„π‡´≈≈å°—∫¿“¬πÕ°
‡´≈≈å ‚¥¬æ∫«à“„π ¿“«–∑’Ë¡’§«“¡‡¢â¡¢âπ¢Õ߇°≈◊Õ
ŸßÀ√◊Õ‡æ‘Ë¡¢÷Èπ®“°ª°µ‘ Õ“√凧’¬Õ∫‡§Á¡π‘¬¡‡æ‘Ë¡
ª√‘¡“≥¢Õß “√∑’Ë∑”Àπâ“∑’Ë√—°…“ ¡¥ÿ≈·√ߥ—π
ÕÕ ‚¡µ‘°√–À«à“ß¿“¬„π°—∫¿“¬πÕ°‡´≈≈å ‚¥¬π”‡¢â“
¡“®“°Õ“À“√∑’ËÕ¬Ÿà¥â“ππÕ°‡´≈≈å¡“°°«à“ —߇§√“–Àå
¢÷Èπ¡“„À¡à (√Ÿª∑’Ë 3.3) “√∑’Ë∑”Àπâ“∑’Ë√—°…“ ¡¥ÿ≈·√ß
¥—πÕÕ ‚¡µ‘°√–À«à“ß¿“¬„π°—∫¿“¬πÕ°‡´≈≈å¢Õß
‡Õ“√凧’¬·∫àßÕÕ°‡ªìπ 3 °≈ÿà¡ §◊Õ 1) “√Õ‘π∑√’¬å∑’Ë¡’
ª√–®ÿ≈∫·≈–∫«° (zwitterionic Solutes) ‡àπ ‡∫∑“Õ’π
Õ‘§‚∑Õ’π ·≈–‰Œ¥√Õ°´’Õ‘§‚∑Õ’π (hydroxyectoine)
2) “√Õ‘π∑√’¬å∑’ˉ¡à¡’ª√–®ÿ(noncharged solutes) ‡àπ
∑’Œ“‚≈ ·≈– ‡Õπ-Õ–´‘∑‘≈°≈Ÿµ“¡‘π‘≈°≈Ÿµ“‡¡µ ‡Õ‰¡¥å
(acetylglutaminylglutamine amide) 3) “√Õ‘π∑√’¬å
∑’Ë¡’ª√–®ÿ ÿ∑∏‘‡ªìπ≈∫ (anionic solutes) ∑’Ë¡’À¡Ÿà
carboxylic phosphate À√◊Õ sulfate ‡àπ ·Õ≈-·Õ≈ø“-
°≈Ÿµ“‡¡µ (L-α-glutamate) ·≈– ´—≈‚ø∑’Œ“‚≈ µ—«Õ¬à“ß
°“√‡æ‘Ë¡ª√‘¡“≥¢Õß “√∑’Ë∑”Àπâ“∑’Ë√—°…“ ¡¥ÿ≈·√ߥ—π
ÕÕ ‚¡µ‘°√–À«à“ß¿“¬„π°—∫¿“¬πÕ°‡´≈≈凡◊ËÕÕ“√凧’¬
Õ∫‡§Á¡‡®√‘≠„π ‘Ëß·«¥≈âÕ¡∑’Ë¡’‡°≈◊Õ ‚¥¬‡√‘Ë¡µâπ®“°
Õ“√凧’¬Õ∫‡§Á¡®–‡æ‘Ë¡ª√‘¡“≥‚æ·∑ ‡´’¬¡‰ÕÕÕπ
·≈–µ“¡¥â«¬°“√‡æ‘Ë¡ª√‘¡“≥¢Õß L-(-glutamate (G-)
¿“¬„π‡´≈≈å®π ¡¥ÿ≈°—∫ª√‘¡“≥¢Õß‚æ·∑ ‡´’¬¡
‰ÕÕÕπ (√Ÿª∑’Ë 3.4) ‚¥¬æ∫«à“„πà«ß∑’Ë¡’°“√ª√—∫ ¡¥ÿ≈
®–‰¡à¡’°“√‡®√‘≠‡µ‘∫‚µ¢ÕßÕ“√凧’¬Õ∫‡§Á¡ ®π
°√–∑—Ë߇¢â“ Ÿà ¿“«– ¡¥ÿ≈Õ“√凧’¬Õ∫‡§Á¡®–‡®√‘≠
‡µ‘∫‚µÕ¬à“ߪ°µ‘„π ¿“«–·«¥≈âÕ¡∑’Ë¡’‡°≈◊Õ·≈–Õ“®¡’
°“√ —߇§√“–Àå “√∑’Ë∑”Àπâ“∑’Ë√—°…“ ¡¥ÿ≈·√ߥ—π
ÕÕ ‚¡µ‘°√–À«à“ß¿“¬„π°—∫¿“¬πÕ°‡´≈≈å¢ÕßÕ“√凧’¬
π‘¥Õ◊ËπÊ (N) (√Ÿª∑’Ë 3.5) “√∑’Ë∑”Àπâ“∑’Ë√—°…“ ¡¥ÿ≈
·√ߥ—πÕÕ ‚¡µ‘°√–À«à“ß¿“¬„π°—∫¿“¬πÕ°‡´≈≈å¢Õß
Õ“√凧’¬ “¡“√∂𔉪ª√–¬ÿ°µå„≥â„π°“√º≈‘µ¬“