This study investigated in what ways and to what extent the interactions between the components of pedagogical content knowledge (PCK) differ for junior high school science teachers with different levels of content knowledge. Data were collected from three science teachers through semi-structured interviews and classroom observations. The participants' content knowledge was analyzed based on inductive coding and the teachers were labeled as curriculum-led, content-expert, and content-novice. Interactions among PCK components were analyzed by making an in-depth analysis of explicit PCK. This included constructing PCK maps for each participant. Then, the constant comparative method was used to clarify differences in interactions among PCK components. Five assertions were proposed based on the differences among PCK interactions: (a) the curriculum-led teacher had the most integrated PCK map and the interactions were mainly reciprocal; (b) the most frequent interactions between knowledge of assessment and the other PCK components were observed in the content-expert teacher; (c) the most frequent interactions between knowledge of curriculum and the other PCK components were observed in the curriculum-led teacher's teaching; (d) the content-novice teacher's orientation interacted with the other PCK components more than in the other two participants' teaching; (e) the main ideas of the interactions among PCK components changed depending on the teachers' content knowledge. The findings are discussed and suggestions for researchers and teachers are provided.