A tanulmányban megvizsgáljuk a KSH által 2001-ben és 2011-ben  elvégzett  népszámlálás  ingázásra  vonatkozó  főbb  adatainak és a két felvétel összehasonlítása során tapasztalt eltérések területi konzekvenciáit. A  vizsgálat  célja  elsősorban  az  volt,  hogy  Győr  köré  szerveződő  ingázó, munkaügyi  vonzásterek jellegzetességeit megismerjük. Ezért az  országos szintű vizsgálatok mellett részletesebben koncentráltunk az észak-Dunántúlra, melynek központrendszerét tártuk fel, s még részletesebben vizsgáltuk ezen belül Győr, s a városkörnyéki tér jellegzetességeit

Chye, ML

Ho, SWT

Mowbray, SL

Rawat, R

Ubhayasekera, W

Von Arnold, S

Wiweger, M

Plant Molecular Biology

Chitinases help plants defend themselves against fungal attack, and play roles in other processes, including development. The catalytic modules of most plant chitinases belong to glycoside hydrolase family 19. We report here x-ray structures of such a module from a Norway spruce enzyme, the first for any family 19 class IV chitinase. The bi-lobed structure has a wide cleft lined by conserved residues; the most interesting for catalysis are Glu113, the proton donor, and Glu122, believed to be a general base that activate a catalytic water molecule. Comparisons to class I and II enzymes show that loop deletions in the class IV proteins make the catalytic cleft shorter and wider; from modeling studies, it is predicted that only three N-acetylglucosamine-binding subsites exist in class IV. Further, the structural comparisons suggest that the family 19 enzymes become more closed on substrate binding. Attempts to solve the structure of the complete protein including the associated chitin-binding module failed, however, modeling studies based on close relatives indicate that the binding module recognizes at most three N-acetylglucosamine units. The combined results suggest that the class IV enzymes are optimized for shorter substrates than the class I and II enzymes, or alternatively, that they are better suited for action on substrates where only small regions of chitin chain are accessible. Intact spruce chitinase is shown to possess antifungal activity, which requires the binding module; removing this module had no effect on measured chitinase activity. © 2009 Springer Science+Business Media B.V.link_to_subscribed_fulltex

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The first crystal structures of a family 19 class IV chitinase: The enzyme from Norway spruce

Chitinases help plants defend themselves against fungal attack, and play roles in other processes, including development. The catalytic modules of most plant chitinases belong to glycoside hydrolase family 19. We report here x-ray structures of such a module from a Norway spruce enzyme, the first for any family 19 class IV chitinase. The bi-lobed structure has a wide cleft lined by conserved residues; the most interesting for catalysis are Glu113, the proton donor, and Glu122, believed to be a general base that activate a catalytic water molecule. Comparisons to class I and II enzymes show that loop deletions in the class IV proteins make the catalytic cleft shorter and wider; from modeling studies, it is predicted that only three N-acetylglucosamine-binding subsites exist in class IV. Further, the structural comparisons suggest that the family 19 enzymes become more closed on substrate binding. Attempts to solve the structure of the complete protein including the associated chitin-binding module failed, however, modeling studies based on close relatives indicate that the binding module recognizes at most three N-acetylglucosamine units. The combined results suggest that the class IV enzymes are optimized for shorter substrates than the class I and II enzymes, or alternatively, that they are better suited for action on substrates where only small regions of chitin chain are accessible.  Intact spruce chitinase is shown to possess antifungal activity, which requires the binding module; removing this module had no effect on measured chitinase activity

Ubhayasekera, Wimal

Rawat, Reetika

Ho, Sharon Wing Tak

Wiweger, Malgorzata

von Arnold, Sara

Chye, Mee-Len

Mowbray, Sherry

Digitala Vetenskapliga Arkivet - Academic Archive On-line

The first crystal structures of a family 19 class IV chitinase : the enzyme from Norway spruce

Publikationer från Uppsala Universitet

Name not available

Chitinases help plants defend themselves against fungal attack, and play roles in other processes, including development. The catalytic modules of most plant chitinases belong to glycoside hydrolase family 19. We report here x-ray structures of such a module from a Norway spruce enzyme, the first for any family 19 class IV chitinase. The bi-lobed structure has a wide cleft lined by conserved residues; the most interesting for catalysis are Glu113, the proton donor, and Glu122, believed to be a general base that activate a catalytic water molecule. Comparisons to class I and II enzymes show that loop deletions in the class IV proteins make the catalytic cleft shorter and wider; from modeling studies, it is predicted that only three N-acetylglucosamine-binding subsites exist in class IV. Further, the structural comparisons suggest that the family 19 enzymes become more closed on substrate binding. Attempts to solve the structure of the complete protein including the associated chitin-binding module failed, however, modeling studies based on close relatives indicate that the binding module recognizes at most three N-acetylglucosamine units. The combined results suggest that the class IV enzymes are optimized for shorter substrates than the class I and II enzymes, or alternatively, that they are better suited for action on substrates where only small regions of chitin chain are accessible.  Intact spruce chitinase is shown to possess antifungal activity, which requires the binding module; removing this module had no effect on measured chitinase activity.</p

Ubhayasekera, Wimal,

Rawat, Reetika,

Ho, Sharon Wing Tak,

Wiweger, Malgorzata,

von Arnold, Sara,

Chye, Mee-Len,

Mowbray, Sherry,

Swepub

The first crystal structures of a family 19 class IV chitinase [Elektronisk resurs] : the enzyme from Norway spruce