Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA.
Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
mBio. 2019 Sep 24;10(5):e02004-19. doi: 10.1128/mBio.02004-19.
Protein-tyrosine phosphorylation in bacteria plays a significant role in multiple cellular functions, including those related to community development and virulence. Metal-dependent protein tyrosine phosphatases that belong to the polymerase and histindinol phosphatase (PHP) family are widespread in Gram-positive bacteria. Here, we show that , a Gram-negative periodontal pathogen, expresses a PHP protein, Php1, with divalent metal ion-dependent tyrosine phosphatase activity. Php1 tyrosine phosphatase activity was attenuated by mutation of conserved histidine residues that are important for the coordination of metal ions and by mutation of a conserved arginine residue, a key residue for catalysis in other bacterial PHPs. The gene is located immediately downstream of the gene encoding the bacterial tyrosine (BY) kinase Ptk1, which was a substrate for Php1 Php1 rapidly caused the conversion of Ptk1 to a state of low tyrosine phosphorylation in the absence of discernible intermediate phosphoforms. Active Php1 was required for exopolysaccharide production and for community development with the antecedent oral biofilm constituent under nutrient-depleted conditions. In contrast, the absence of Php1 had no effect on the ability of to form monospecies biofilms. , Php1 enzymatic activity was resistant to the effects of the streptococcal secreted metabolites pABA and HO, which inhibited Ltp1, an enzyme in the low-molecular-weight (LMW) phosphotyrosine phosphatase family. Ptk1 reciprocally phosphorylated Php1 on tyrosine residues 159 and 161, which independently impacted phosphatase activity. Loss of Php1 rendered nonvirulent in an animal model of periodontal disease. Collectively, these results demonstrate that possesses active PHP and LMW tyrosine phosphatases, a unique configuration in Gram-negatives which may allow to maintain phosphorylation/dephosphorylation homeostasis in multispecies communities. Moreover, Php1 contributes to the pathogenic potential of the organism. Periodontal diseases are among the most common infections of humans and are also associated with systemic inflammatory conditions. Colonization and pathogenicity of are regulated by signal transduction pathways based on protein tyrosine phosphorylation and dephosphorylation. Here, we identify and characterize a novel component of the tyrosine (de)phosphorylation axis: a polymerase and histindinol phosphatase (PHP) family enzyme. This tyrosine phosphatase, designated Php1, was required for community development with other oral bacteria, and in the absence of Php1 activity was unable to cause disease in a mouse model of periodontitis. This work provides significant insights into the protein tyrosine (de)phosphorylation network in , its adaptation to heterotypic communities, and its contribution to colonization and virulence.
细菌中的蛋白酪氨酸磷酸化在多种细胞功能中起着重要作用,包括与群落发育和毒力相关的功能。属于聚合酶和组氨酸醇磷酸酶(PHP)家族的金属依赖性蛋白酪氨酸磷酸酶在革兰氏阳性菌中广泛存在。在这里,我们表明,一种革兰氏阴性牙周病原体,表达一种 PHP 蛋白 Php1,具有二价金属离子依赖性酪氨酸磷酸酶活性。Php1 酪氨酸磷酸酶活性被突变保守组氨酸残基削弱,这些残基对于金属离子的协调很重要,并且被突变保守精氨酸残基削弱,该残基是其他细菌 PHP 中催化的关键残基。基因位于基因的下游,该基因编码细菌酪氨酸(BY)激酶 Ptk1,它是 Php1 的底物。Php1 迅速导致 Ptk1 转化为低酪氨酸磷酸化状态,而没有明显的中间磷酸化形式。在营养缺乏条件下,活性 Php1 是产生 外多糖和群落发育所必需的,而群落发育以前是口腔生物膜成分。相比之下,Php1 的缺失对 的形成单种生物膜的能力没有影响。此外,Php1 酶活性不受链球菌分泌代谢物 pABA 和 HO 的影响,这两种代谢物抑制 Ltp1,Ltp1 是低分子量(LMW)磷酸酪氨酸磷酸酶家族的一种酶。Ptk1 在酪氨酸残基 159 和 161 上磷酸化 Php1,这两个残基独立影响磷酸酶活性。Php1 的缺失使 失去了牙周病动物模型中的毒力。总的来说,这些结果表明,含有活性 PHP 和 LMW 酪氨酸磷酸酶,这是革兰氏阴性菌中的独特配置,可能使 维持多物种群落中的磷酸化/去磷酸化平衡。此外,Php1 有助于该生物体的致病性。牙周病是人类最常见的感染之一,也与全身性炎症状态有关。的定植和致病性受基于蛋白酪氨酸磷酸化和去磷酸化的信号转导途径调节。在这里,我们鉴定并表征了酪氨酸(去)磷酸化轴的一个新组成部分:聚合酶和组氨酸醇磷酸酶(PHP)家族酶。这种酪氨酸磷酸酶,称为 Php1,是与其他口腔细菌群落发育所必需的,并且在没有 Php1 活性的情况下,它不能在牙周炎的小鼠模型中引起疾病。这项工作为 中的蛋白酪氨酸(去)磷酸化网络、其对异型群落的适应以及对定植和毒力的贡献提供了重要的见解。