• 미생물학회지
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• 제25권3호
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• pp.184-188
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• 1987

Evidences that the mannose permease of Escherichia coli mediates the infection of N4 in early steps, were obtained as follows. First, A mutant strain of Escherichia coli which was resistant to both wild type N4 and lambda whose genome is Charon 4A containing human genomic fragments in its EcoR I site, could not use mannose efficiently. Second, N4 could not infect pel mutant strains which lack one or all of intact components of mannose permease. However, unknown alterations in N4 made it possible for the phage to infect pel mutant of E. coli. It also turned out to be clear that the receptor of N4 was different from that of lambda.

• Journal of Microbiology and Biotechnology
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• 제18권7호
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• pp.1227-1234
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• 2008

Pseudomonas aeruginosa is an opportunistic human pathogen that produces and secretes exopolysaccharides (EPS), in which cells are embedded to form a highly organized community structure called biofilm. Here, we characterized the role of cyclic diguanylate (c-di-GMP) and EPS (PEL) overproduction in the wspF mutant phenotypes of P. aeruginosa PA14 (wrinkly appearance, hyperadherence, impaired motilities, and reduced virulence in acute infections). We confirmed that the elevated c-di-GMP level plays a key role in all the wspF mutant phenotypes listed above, as assessed by ectopic expression of a c-di-GMP-degrading phophodiesterase (PvrR) in the wspF mutant. In contrast, PEL EPS, which is overproduced in the wspF mutant, was necessary for wrinkly appearance and hyperadherence, but not for the impaired flagellar motilities and the attenuated virulence of the wspF mutant. These results suggest that c-di-GMP affects flagellar motility and virulence, independently of EPS production and surface adherence of this bacterium.

• Journal of Microbiology and Biotechnology
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• 제14권5호
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• pp.1047-1051
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• 2004

The phytopathogenic bacterium Pectobacterium chrysanthemi secretes multiple isozymes of plant cell wall disrupting enzyme such as pectate lyase and cellulase. The cel gene, existing in tandem with the pel gene, was isolated previously [10]. The role of Cel5Z and PelL1 in P. chrysanthemi PY35 pathogenicity on potato tissues was assessed by mutagenizing cloned cel gene and pel gene in tandem and recombining them with the chromosomal alleles. Strains with the Km cassette interposon in pelL1 or a double mutant showed a delay in the appearance of symptoms, suggesting that P. chrysanthemi PY35 pectate lyase PelL1 may playa minor role in soft-rot pathogenesis.

• 한국미생물·생명공학회지
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• 제19권3호
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• pp.222-227
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• 1991

Rhizobium fredii USDA193은 대두(Peking)의 근모 세포벽에 침투하여 근류를 형성한다. 본 실험에서는 전보 (1)에서 분리 보고한 R.fredii의 pectate lyase 유전자 clone(SY1)으로부터 $\Omega$변이를 시켰다. 이것을 R.fredii USDA193에 다시 marker-exchange시켜 얻은 변이주(R.fredii USDA193$\Omega$와 R.fredii USDA193omega1)의 pectate lyase 활성이 완전히 block되지 못하였다. R.fredii 내에서는 다른 종류의 pel 유전자가 존재하 것으로 생각되며 pelB 및 pelE의 Rhizobium mutants들은 근류형성 초기단계에서 직접적으로 영향을 미치지 못하였다.